HomeMy WebLinkAboutFolderFOR OFFICE USE ONLY
P&Z Case No.: [!)' J1l-C>1
Date Submitted: /D
DP-Q()-1%
FINAL PLAT APPLICATION
; V7;r~
~ QC<:ffiS Prai.ft0
(Check one) D Amending
($300.00)
~Final
($400.00)
0 Vacating
($400.00)
0 Replat
($600.00)"
*Includes public hearing fee
The following items must be submitted by an established filing deadline date for P&Z Commission
consideration.
MINIMUM SUBMITTAL REQUIREMENTS:
DJ Filing Fee (see above) NOTE. Multiple Sheets -$55.00 per additional sheet
1 D Variance Request to Subdivision Regulations -$100 (if applicable)
--·-1
I
!
I
!ZJ' Development Permit Application Fee of $200.00 (if applicable).
~ Infrastructure Inspection Fee of $600.00 (applicable if any public infrastructure is being constructed)
I ~ Application completed in full. I [XJ Thirteen (13) folded copies of plat. (A signed myl ar original must be submitted after staff review.)
, [2J One (1) copy of the approved Preliminary Plat and/or one (1) Master Plan (if applicable).
[XI Paid tax certificates from City of College Station, Brazos County and College Station 1.S.D.
~ A copy of the attached checklist with all items checked off or a brief explanation as to why they are not.
~ Two (2) copies of public infrastructure plans associated with this plat (if applicable).
! D Parkl and Dedication requirement approved by the Parks & Recreation Board, please provide proof of l ___ approval (if applicable). ______ _
NAME OF SUBDIVISION 5pitVy fY?c-,av/o 1,v 5 .5.,, iJA(u/),:B7r Ph c s e -"7).::--
SPECIFIED LOCATION OF PROPOSED SUBDIVISION (Lot & Block) __________ _
AF PLICANT/PROJECT MANAGER'S INFORMATION (Primary Contact for the Project):
Name Len LDood :5. 4o/a ric. . ?.£ //7/P6-E-Mail _______ _
//
Street Address 2£21' Te-x::u. 5 19 v.c. S'o,4 dJ1 -;5,, ,----le d
City C0 !IC<) c-5~ /-,' C/ Vl State /e-~ °' S Zip Code 7 /Bc:J.o ____ _
Phone Number (p 1 3> -2= 3 s-7 Fax Number _C~o~9~3_-_4-_z.._4_3~---
CURRENT PROPERTY OWNER'S INFORMATION:
additional sheet, if necessary)
Name We,A d /h'!& r-Luc !tJvmr':/I f L TJ) .,., -' ~ I
Street Address P 6 , E 0 y / o 1 Cf S--
(All owners must be identified. Please attach an
E-Mail _____________ _
City C.Ol foy= ?--h --ban Sta te _ _,1--...__....,X~----Zip Code 7 78-~
Phone Number f31-{o ~ 88 4~ Fax Number '?fJ0-/ 6 79
ARCHITECT OR ENGINEER'S INFORMATION:
Name 4,...,00~ S , 4tQvn s, ? £. E-Mail L.¥=---l --------------
Street Address ZL:"L I /<.:::--x<. z f}-ve r 5:>11 +h °5 l.( 7 fcs-ft
City C.. !lf?5e-5-k --/-/on State _26-~_C?< S Zip Code r7 $ 4-:o
Phone Number 0 9 3,_ S-3 S/ Fa x Number <2?9 3 -4-z.4 3
1-Aug-02 1 or 5
Acreage Total Property 32. a 7 Total# Of Lots 8_7 __ _
Existing Use: R<t ....v 4"' a/ Proposed Use:
R-0-W Acreage 4 . o ~
Ro5 /c/Aff/,t;~ :)«£,,/,' I! r';; /a k(
Number Of Lots By Zoning District 8 7 I ~ ) I __ --/ __ _
Average Acreage Of Each Residential Lot By Zoning District:
__ ! 8 I ! __ __ / __ __/ __ _
Floodplai n Acreage _______________________________ _
A Statement Addressing A ny Differences Between The Final Pl at And Approved Master Development Pl an
And/Or Preliminary Pl at (I f A pplicabl e):
Requested Variances To Subdivision Regu lations & Reason For Same: ____________ _
Requested Oversize Participation: ---------------------------~
Total Linear Footage of
Proposed Public:
4 4-"3 o Streets
3 , ~o o Sidewalks
C; z -{ I Sanitary Sewer Lines
~,I D -:/ Water Lines )
Channels
3 . 3 o 0 Storm Sewers >
/DO Bike Lanes I Paths
Parkland Dedication due pri or to filing the Final Pl at:
ACREAGE:
# of acres to be dedicated + $ development fee ----
--# of acres in floodplain
# of acres in dete ntio n --
--# of acres in greenways
OR
FEE IN LI EU OF LAND:
Previo,,._5 ty a.dc/;enSec/
-t-h ~ o l.<7 h D--v~1 he_ I+
-Ve, fo-7,
#of Single-Family Dwelling Units X $556 = $ ___ _
__ (date) Approved by Parks & Recreation Board
NOTE: DIGITAL COPY OF PLAT MUST BE SUBMITTED PRIOR TO FILING.
The applicant has prepared this application and certifies that the facts stated herein and exhibits attached
hereto are true, correct and complete. The undersigned hereby requests approval by the City of College
Station of the above-identified fin al plat and attests that this request does not amend any covenants or
re st1ictions associated with this plat.
~
E°"(CDA-/.~
Vi c.e Pn;r;'5iqf:n-±
Signature and Title Date
1-Aug-02 2 of 5
FOR OFFICE USE ONLY
Case No. ________ _
Date Submitted
DEVELOPMENT PERMIT
MINIMUM SUBMITTAL REQUIREMENTS
$200.00 Development Permit Application Fee.
Drainage and erosion control plan, with supporting Drainage Report two (2) copies each
Notice of Intent (N .0 .1.) if disturbed area is greater than 5 acres
LEGAL DESCRIPTION ~'''"'O ~efov..J 5 6ubd,\2,·s /19/1 f>),""'9B zz=
APPLICANT (Primary Contact for the Project):
Name &nu.X>OL6. Jl.~ rT1 5 , 1. Er / M Db-l
E-Mail ____________ _
Street Address Z5=SI Tam::'> A-ve So,.,.,+tq s ..... ,·Jc &-
City Co // G-66-;5 -lg -J-r'D n
Phone Number G ? 3 -3=3 S--1
State t,;.x0 "2 Zip Code Z?F4"""""o ____ _
PROPERTY OWNER'S INFORMATION:
Name WtrJdAnL/dJ/.z him-4pm¢?1 f-.?IP
Street Address P C>, Boy /C> 19' :s:
City Co//~ .a-6 &. I:/ t7 Yi State ]: :X:-
Phone Number 8 4(p _ 8 8 4 S--
ARCHITECT OR ENGINEER'S INFORMATION :
Name Mtiwooa/6 4ot6µAs 1 ?c. >
FaxNumber_~&=~9:.............3~--<=f_,_._2=--i4~1----
c/{p 'Fra.,,, j< /hv.Y-l'>"f4;f~
E-Mail ____________ _
Zip Code cr 8~4~2::.~--
Fax Number ____________ _
E-Mail ____________ _
Street Address -z~-s=-r TeX'?-<-s d 1.h::~., S:. µ -fh 5',d. ,' --1-e: A
City a<> /k?;; ~ :/-k ..J-10M State t:.>< Zip Code r7!3._4:-'----"C>~---
Phone Number --------------Fax Number ____________ _
Application is hereby made for the following development specific site/waterway alterations:
ACKNOWLEDGMENTS:
I, , design engineer/owner, hereby acknowledge or affirm that:
./en~ :5 .-1/t:/4 l?t 5
The information and conclusions contained in the above plans and supporting documents comply with the
current requirements of the City of College Station, Texas City Code, Chapter 13 and its associated Drainage
Policy and Design Standards.
As a condition of approval of this permit application, I agree to construct the improvements proposed in this
application according to these documents and the requirements of Chapter 13 of the College Station City
Code
Property Owner(s)
1-Aug-02
Contractor
1 of 2
CERTIFICATIONS: (for proposed alterations within designated flood hazard areas.)
A. I, , certify that any nonresidential structure on or proposed to be on this site as part of this
application is designated to prevent damage to the structure or its contents as a result of flooding from
the 100 year storm.
Engineer Date
B. I, , certify that the finished floor elevation of the lowest floor, including any basement, of any
residential structure, proposed as part of this application is at or above the base flood elevation
established in the latest Federal Insurance Administration Flood Hazard Study and maps, as
amended.
Engineer Date
C. I, , certify that the alterations or development covered by this permit shall not diminish the flood-
carrying capacity of the waterway adjoining or crossing this permitted site and that such alterations or
development are consistent with requirements of the City of College Station City Code, Chapter 13
concerning encroachments of floodways and of floodways fringes.
Engineer Date
D. I, , do certify that the proposed alterations do not raise the level of the 100 year flood above
elevation established in the latest Federal Insurance Administration Flood Hazard Study.
Engineer Date
Conditions or comments as part of approval: -----------------------
In accordance with Chapter 13 of the Code of Ordinances of the City of College Station, measures shall be
taken to insure that debris from construction , erosion , and sedimentation shall not be deposited in city streets,
or existing drainage facilities. All development shall be in accordance with the plans and specifications
1-Aug-02 2 of 2
submitted to and approved by the City Engineer for the above named project. All of the applicable codes and
ordinances of the City of College Station shall apply.
1-Aug-02 3 of 2
SUPPLEMENTAL DEVELOPMENT PERMIT INFORMATION
Application is hereby made for the following development specific site/waterway alterations:
ACKNOWLEDGMENTS:
I, , design engineer/owner, hereby acknowledge or affirm that:
The information and conclusions contained in the above plans and supporting documents comply with the
current requirements of the City of College Station, Texas City Code, Chapter 13 and its associated Drainage
Policy and Design Standards. As a condition of approval of this permit application, I agree to construct the
improvements proposed in this application according to these documents and the requirements of Chapter 13
of the College Station City Code.
Property Owner(s) Contractor
CERTIFICATIONS: (for proposed alterations within designated flood hazard areas.)
A. I, certify that any nonresidential structure on or proposed to be on this site as part of this
application is designated to prevent damage to the structure or its contents as a result of flooding from the
100 year storm.
Engineer Date
B. I, certify that the finished floor elevation of the lowest floor, including any basement, of any
residential structure, proposed as part of this application is at or above the base flood elevation established in
the latest Federal Insurance Administration Flood Hazard Study and maps, as amended.
Engineer Date
C. I, , certify that the alterations or development covered by this permit shall not diminish the flood-
carrying capacity of the waterway adjoining or crossing this permitted site and that such alterations or
development are consistent with requirements of the City of College Station City Code, Chapter 13
concerning encroachments of floodways and of floodway fringes.
Engineer Date
D. I, , do certify that the proposed alterations do not raise the level of the 100 year flood above
elevation established in the latest Federal Insurance Administration Flood Hazard Study.
~=== ,&r/_;z/oz_
Engineer Len..Pt3~a-rn 5 Date
Conditions or comments as part of approval: __
In accordance with Chapter 13 of the Code of Ordinances of the City of College Station, measures shall be
taken to insure that debris from construction, erosion, and sedimentation shall not be deposited in city streets,
or existing drainage facilities. All development shall be in accordance with the plans and specifications
submitted to and approved by the City Engineer for the above named project. All of the applicable codes and
ordinances of the City of College Station shall apply.
1-Aug-02 5 of 5
NO.
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NO.
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LARRY OR PATTI WELLS 9796934243
SPRING MEADOWS PHASE TWO
ESTIMATE OF PROBABLE COST
PROPOSED STREET CONSTRUCTION
DESCRIPTION QUANITY UNIT UNIT COST
Mobilization 1 L.S. $30,000 .00
Prepare Right-of-Way 15,600 S.Y. $8.00
6" Lime Treated Subgrade 15,600 S.Y. $ 3.50
6" Limestone Base 15,600 S.Y. $ 10.00
2" HMAC Surface 15,600 'S.Y. $ 4.00
Masonary Pillars 4 EA $ 300.00
Stamped and Dyed Concrete 30 S.F. $ 16.00
Dyed Concrete 30 S.F. $ 12.00
Reinforced Concrete Curb and Gutter 300 L.F. $ 12.00 (City of College Station)
Mountable Curb 7000 L.F. $ 10.00
Reinforced Concrete Sidewalk 3,700 L.F . $ 6.00
Street Light Conduit 2,240 L.F. $ 6.00
Street Light Foundations 15 EA $ 750.00
Electrical Conduit 5,260 L.F. $5 .00
Erosion Control 1 L.S. $20,000.00
TOTAL STREET CONSTRUCTION =
PROPOSED SAN.ITARY _SEWER IMPROVEMENTS
DESCRIPTION QUANITY UNIT UNIT COST
Proposed 4" Sanitary Sewer Service Line (SOR 4 EA $ 900.00 26, Class160) Single
Proposed 4" Sanitary Sewer Service Line (SOR 22 EA $ 1,100.00 26, Class160) Double
Proposed 6" Sanitary Sewer Line 3525 LF $ 16.00 (SOR 26, Class160)
Proposed 8" Sanitary Sewer Line 750 LF $ 21.00 (SOR 26, Class160)
Manholes 20 EA $ 2,500.00
Cement Stabilized Sand 3000 LF $ 10.00
TOTAL STREET CONSTRUCTION=
P.02
TOTAL COST
$ 30,000.00
$ 124,800.00
$ 54,600.00
$ 156,000.00
$ 62,400.00
$ 1,200.00
$ 480.00
$ 360.00
$ 3,600.00
$ 70,000.00
$ 22,200.00
$ 13,440.00
$ 11,250.00
$ 26,300.00
$ 20,000.00
$596,630.00
TOTAL COST
$ 3,600.00
$ 24,200.00
$ 56,400.00
$ 15,750.00
$ 50,000.00
$ 30,000.00
$ 179,950.00
NO.
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NO.
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LARRY OR PATTI WELLS 9796934243 P.03
PROPOSED WATER IMPROVEMENTS
DESCRIPTION QUANITY UNIT UNIT COST TOTAL COST
2" Water Service Line (SOR 21, Class 200)
Single
2 EA. $ 200.00 $ 400.00
2" Water Service Line (SOR 21 , Class 200) 25 EA. $ 250.00 $ 6,250.00 Double
8" Water Line (SOR 21 , Class 200) 4,400 EA. $ 21 .00 $ 92,400.00
2" Water Air Release Valve and Box 1 EA. $ 600.00 $ 600.00
Blow Off Valve and Box 5 EA. $ 600.00 $ 3,000.00
Standard Fire Hydrant 6 EA. $ 2,500.00 $ 15,000.00
8" Gate Valve and Box 12 EA. $ 550.00 $ 6,600.00
8"X8" MJ Tee 6 EA. $ 400.00 $ 2,400.00
8"X90° MJ Bend 2 EA. $ 350.00 $ 700.00
8" x 45° MJ Bend 1 EA. $ 375.00 $ 375.00
18"X8" MJ Tapping Valve and Sleeve with Gate 1 EA. Valve $ 800.00 $ 800.00
Traffic Control 1 EA. $ 5,000.00 $ 5,000.00
TOTAL WATER IMPROVEMENTS= $ 133,525.00
PROPOSED STORM.SEWER, GRADING AND DRAINA,GE
DESCRIPTION QUANITY UNIT UNIT COST TOTAL COST
30" Reinforced Concrete Drainage Pipe 900 L.F.
36" Reinforced Concrete Drainage Pipe 1 ,500 L.F.
42" Reinforced Concrete Drainage Pipe 1 ,200 L.F.
Detention Pond Excavation and Compaction 1 L.S.
5' Storm Sewer Inlet 8 EA.
7' Storm Sewer Inlet 3 EA.
8' Storm Sewer Inlet 3 EA.
1 O' Storm Sewer Inlet 2 EA.
11' Storm Sewer Inlet 1 EA.
Junction Boxes 8 EA.
Concrete Weir Wall with Baffle Blocks 1 L.S.
Creek Rip-Rap 1 LS
Splash Pad 1 LS
3' Concrete Valley Gutter 355 LF
TOTAL CONSTRUCTION PRICE
$ 35.00
$ 40.00
$ 50.00
$ 30,000.00
$ 2,500.00
$ 2,800.00
$ 3,000.00
$ 3,400.00
$ 3,500.00
$ 2,500.00
$ 37,ooo:oo
$ 28,000.00
$ 1,400.00
$ 13.50
$
$
$
$
$
$
$
$
$
$
$
$
$
$
31,500.00
60,000.00
60,000.00
20,000.00
20,000.00
8,400.00
9,000.00
6,800.00
3,500.00
20,000.00
37,000.00
28,000.00
1,400.00
4,792.50
$1,220,497.50
(E-mailed with Final Plat comments -10110102)
DP-SPRING MEADOWS SUB PH 2 (DP) (02-00100048)
ENGINEERING REVIEW
COMMENTS No. 1
1. Drainage report not approved. Please show flow into inlet, pipe size , pipe
flow (010 and 0100), pipe slope, etc. Inlets in report do not correspond to
inlets on drawings. Please see design manual for requirements.
2. HGL must be shown on plans or report.
3. Please remember pipes 24" and smaller have a 75% reduced cross sectional
area. Many engineers calculated the actual flow and then use an adjusted
flow of actual flow times 1.33 . Check pipe to see if pipe will handle adjusted
flow. This way you can use your programs. Otherwise, you have to use the
actual flow and reduce the area of the pipe .
4. On post development area map, where does area 2 end and 4 begin?
5. These are a few comments to assist you for another report.
6. In order to issue a development permit and release construction documents
we will need the following: sealed engineer's estimate of infrastructure costs,
NOi, approved drainage report, approved plat, approved plans, etc.
7. The certification to ensure property is safe from flooding is for you to design
and approve the fill placed on those lots. Once that is assured , those
properties can than apply to be "out" of the floodplain with no insurance
requirement. By signing the document now, you have assured those
properties that they are currently "reasonably safe from flooding ".
Reviewed by: Spencer Thompson Date : October 10, 2002
NOTE: Any changes made to the plans, that have not been requested by the City of College
Station , must be explained in your next transm ittal letter and "bubbled" on your plans. Any
additional changes on these plans that have not been pointed out to the City of College Station will
constitute a completely new review.
(f ~ DEVELOPMENT PERMIT
PERMIT NO. 02-48
Project: SPRING MEADOWS SUBDIVISION
COLllGE STATION FOR AREAS INSIDE THE SPECIAL FLOOD HAZARD AREA
RE: CHAPTER 13 OF THE COLLEGE STATION CITY CODE
SITE LEGAL DESCRIPTION:
SPRING MEADOWS
SUBDIVISION
DATE OF ISSUE: 02/03/03
OWNER:
THURMOND, FRANK
JERRY WINDHAM
PO BOX 10195 , COLLEGE STATION TX 77842
SITE ADDRESS:
308 GREENS PRAIRIE ROAD
DRAINAGE BASIN:
Alum Creek
VALID FOR 12 MONTHS
CONTRACTOR:
TYPE OF DEVELOPMENT: Full Development Permit
SPECIAL CONDITIONS:
All construction must be in compliance with the approved construction plans
All trees must be barricaded, as shown on plans, prior to any construction. Any trees not barricaded will not
count towards landscaping points. Barricades must be 1' per caliper inch of the tree diameter.
The Contractor shall take all necessary precautions to prevent silt and debris from leaving the immediate
construction site in accordance with the approved erosion control plan as well as the City of College Station
Drainage Policy and Design Criteria. If it is determined the prescribed erosion control measures are ineffective
to retain all sediment onsite, it is the contractors responsibility to implement measures that will meet City, State
and Federal requirements. The Owner and/or Contractor shall assure that all disturbed areas are sodden and
establishment of vegetation occurs prior to removal of any silt fencing or hay bales used for temporary erosion
control. The Owner and/or Contractor shall also insure that any disturbed vegetation be returned to its original
condition, placement and state. The Owner and/or Contractor shall be responsible for any damage to
adjacent properties, city streets or infrastructure due to heavy machinery and/or equipment as well as erosion,
siltation or sedimentation resulting from the permitted work.
Any trees required to be protected by ordinance or as part of the landscape plan must be completely fenced
before any operations of this permit can begin.
In accordance with Chapter 13 of the Code of Ordinances of the City of College Station, measures shall be
taken to insure that debris from construction , erosion, and sedimentation shall not be deposited in city streets,
or existing drainage facilities.
I hereby grant this permit for development of an area inside the special flood hazard area. All development
shall be in accordance with the plans and specifications submitted to and approved by the City Engineer in the
development permit application for the above named project and all of the codes and ordinances of the City of
College Station that apply.
Da I
'Z/o;r/03
Owner/AgenUContractor Date
/
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D, 28 ~
0 I ~o J;
<b I f'/,.1 y fJ, _,
-d--/cfs
M-1 ZONE /
EXHIBIT DRAWING 2
POST -DEVELOPMENT
DRAINAGE AREAS
33.24 ACRES
SCALE: 1"=100'
gRfNjE lllEAKQOWN
~ -11.82 M:RES 0 -VJ7 M:RES () -12.29 ACRES ~ _ 5.07 >CRES e -5.19 M:RES
January 17, 2003
CITY OF COLLEGE STATION
DEVELOPMENT SERVICES
1101 Texas Avenue South, PO Box 9960
College Station, Texas 77842
Phone (979) 764-3570 I Fax (979) 764-3496
MEMORANDUM
TO: Ronald M. Smith, Via fax 696.5996
FROM: Bridgette George, Asst. Development Manager
SUBJECT: Southside Plaza(Aggieland Carpet One)
The City's Comprehensive Plan shows an 18-inch waterline is proposed across the
front of the subject property. The 18-inch line is also an impact fee line to provide
service to the area. Therefore; you willl be responsible for constructing an 18-inch
waterline from where the line terminates on the Harley Davidson property through your
property to the northwest property line.
You may request oversize participation (OP) for the construction of this line. Your
proposal may include the cost difference between an 8-inch and an 18-inch waterline
from the existing waterline to the lead for the westernmost fire hydrant (as shown on the
Site Plan). You may also include 100% of the cost for the extension of the 18-inch
water line the remaining distance to the property line.
Staff has determined that an 8-inch line will support the requirements of your site. You
will need to provide an hydraulic analysis if you choose to use a 6-inch line to meet
requirements.
In the OP request, you may also include the impact fees that will be required at time of
building permit. The fees may be shown as credit items against the OP amount to help
alleviate the cash outlay on the developer until the water line is accepted and the OP
released.
The Impact Fee per Dwelling Unit Equivalent (DUE) which is based on domestic water
meter size is $550/DUE. For example, assuming the 7 meters indicated on your Site
Plan (Phase 1) are 3/4-inch, the resulting Impact fee is $9,900. The impact fee
increases with increasing meter size .
cc: Rabon Metcalf, Via fax 690.0329
Case file #02-00500273
STAFF REVIEW COMMENTS NO. 3
Project: KRENEK CROSSING (DARTMOUTH) (PP) -02-00500186
ENGINEERING
1. Tie Plat to City Monument or known platted corner.
2. Locate fire hydrants on lot line between Lot 1 and Lot 2. Lengths of streets would
allow a blow off instead of additional fire hydrant.
3. Provide a public utility easement for the sanitary sewer line through Lot 2, Block 3.
4. Label existing easements and provide volume and page numbers.
5. Remove Note 9 from General Notes.
Reviewed by: Carol Cotter Date : January 17, 2003
NOTE: Any changes made to the plans, that have not been requested by the City of College Station,
must be explained in your next transmittal letter and "bubbled" on your plans. Any additional changes on
these plans that have not been pointed out to the City, will constitute a completely new review.
2 of 2
I ,
DP-SPRING MEADOWS SUB PH 2 (DP) (02-00100048)
ENGINEERING REVIEW COMMENTS No. 2
1. Sheet C5: sufficient cover on storm drain Line D?
2. Sheet CS : manhole does not need to be a drop manhole.
3. C22 : label hydrant on profile.
4. C24: casing is for sewer/water. Center on sewer.
5. C25: drawing shows two sewer lines on Spring Grove Court?
6. C26: Show tee in profile.
7. C27: at Sta. 5+90, is this a fitting? Label tee at Sta. 7+40 on water.
8. C28: Does water and sewer have 2-ft separation?
9. C29: fitting on water at Sta. 1 +50. Water service is through sleeve?
10. Show detail for outlet structure at Spring Creek.
11 . Change street cross section to show asphalt.
I faxed to you the J-box standard and City cement stabilized mixture. Please let me
know if you did not receive.
Please consider CLOMR-F issues on rear lots.
Let me know if you have any questions.
Reviewed by: Spencer Thompson Date: January 14, 2003
NOTE: Any changes made to the plans, that have not been requested by the City of College Station, must
be explained in your next transmittal letter and "bubbled" on your plans. Any additional changes on these
plans that have not been pointed out to the City of College Station will constitute a completely new review.
Home of Texas A&M University
City of College Station and
Spring Meadows H.O.A.
Dear Robert Sleeper and Spring Meadows HOA,
October , 2013
This letter and attached images represent a request for maintenance and possible improvements to the
drainage/watershed of the subdivision of Spring Meadows and the City owned greenbelt that surrounds
it. It is a relatively complex problem that will take some explaining to fully understand. I will start with a
short history, and address the localized problem around my lot and the surrounding lots, and proceed to
the lower watershed problems.
History and Explanation:
I purchased and moved into 4446 Spring Meadows at the end of April 2013. Within the first week or
two of living here we had a strong storm system come through that dropped a few inches of rain.
During the event, the culvert in front of my house backed up and was unable to take on the water that it
was supposed to be draining. The water backed up and eventually began flowing through my front yard,
and past my house on the side making a lake that covered the front yard and most of the street. The
overflow was not very significant, but it was apparent that the culvert was unable to handle strong
storms. We witnessed a second overflow at the next rain event, and then another one last night. Last
night's flood event, being a particularly strong storm, revealed much more significant flooding and
therefore high potential for significant property damage. Water came up to the top of the slab on my
house. It washed away the pumpkins on my porch and was just below the lip of my door. The water
came about 4" high on my garage door and flooded 2/3 of my garage. Had the water come one more
inch higher, it would have entered our home. My neighbors at 4444 Spring Meadows also had water up
to the top of their slab. They are out of town so I do not know if water entered their home at this time.
The fact that the shortcomings of the drainage culvert caused flood waters to rise to within one inch of
flooding my house, I am forced to bring this to your attention in order to prevent the next strong storm
from being the one that floods the house.
I will show more detail on last night's flood event below. I used to design retention ponds in an
engineering role and understand hydrology pretty well. I used this knowledge to look at the entire
drainage system as the problem with the culvert is not just as simple as being designed too small or
having too small of an opening, etc .. Rather it is a problem that extends hundreds of feet on either side
of my house at different levels and on HOA property and City of College Station property. I will explain
below starting with the culvert, then moving to the HOA retention pond and City property. Please
read through it all.
•
Problemsabove the culvert at 4446 Spring Meadows:
The culvert is designed to drain the areas in blue in the image below. However, at least some of the
culverts up Spring Meadows (green arrows) flow underground into this culvert -if not the entire half of
the subdivision-. During these events, the drains in green tend to fill, allowing the excess water to flow
down Spring Meadows to the last drain, the one in front of my house. The water that they are actually
taking on also flows through the culvert in front of my house. I do not have photos, but these flood
events deposit flood debris several feet into the grass on either side of Spring Meadows all the way to
Cold Springs and beyond, indicating an inability to properly drain the streets. Essentially, the point here
is that the drainage system is undersized for the area it is designed to drain. The culvert is already full
from the water com ing in from the upstream culverts, and has to take the overflow water as well.
As mentioned above, the culvert in front of my house is incapable of handling strong rain events and is
consistently overflowing. As a result, it backs up filling the street and surrounding yards, and overflows
between the houses on the north side of Spring Meadows (4444, 4446, and 4448 Spring Meadows). The
image below shows the layout and extension of the flooding as it relates to these houses.
It flows between 4444 and 4442 as well, but I have not documented this.
The image above shows flooding on May 9th, 2013 showing the culvert overflowing and beginning to
flow through my front yard. Note the amount of water in the street which is not being collected by the
culverts further up the road. One of these culverts is just to the right of the bush/tree at the top left of
the image.
On 10/13/2013, the flooding occurred in the middle of the night and I was only able to see the resulting
problems when I went outside to inspect about 8:30am, approximately six hours after the storm first hit.
The following images document how the flood occurred and potential damages if it were to have been
just a little worse.
Flood debris line in my yard is just below the red lines. My house is the one on the right.
Flood line is visible just below the red lines, note that it is level with my slab .
Image showing the water level debris on my front porch, slightly above the concrete of my slab.
This is my garage door showing the height of thewater
The interior of my garage after the water receded. Debris lines showed the water to the front tire and
the black furniture at the top of the image.
Water level on 4444 Spring Meadows home between our houses.
Water level at my mailbox, which is right next to the culvert. It showed the water to be 28" above the
street flow line. Water of this depth essentially cuts off access to my house and can flood vehicles
nearby.
Mailbox at 4444 Spring Meadows shows water depth at 16" above the sidewalk.
As you can see, the front yards of at least 4444 and 4446 spring meadows completely filled to just below
our slab level. The culvert was unable to take the water it was designed for. This was too close of a call
and another storm is looming tonight as I type this.
Looking at the bigger picture; Retention Pond and City property
The first thing I noticed this morning in the 8:00 hour was that the culvert in front of my house was still
full of water inside. The water that was flowing in out of the street only dropped about 6" to a pool.
The drain pipe exiting the culvert was not visible due to the height of the water. This pipe exits the
ground behind my house and into the retention pond for Spring Meadows. See the map below for a full
geographical layout of the situation.
Wondering why the culvert was backed up as bad as it was I began looking at the full situation
downstream of the culvert. This is what I found. The retention pond was partially full (not flowing over
the top), the water on the other side of the overflow dam was just slightly lower than the water inside
the retention pond, see image below:
Based on my understanding of retention ponds, they are designed to retain water and release it at a
more natural speed, basically slow the water. So the water should be able to freely flow from the drain
holes in the overflow wall and cascade away. This is not occurring in this retention pond . The swamp,
as I will call it for now, that the retention pond flows into (on City property) fills up just as the retention
pond does. This pushes back pressure on the retention pond and preventing the water from freely
flowing out of the retention pond. The water levels on either side of the overflow are relatively
constant, even when the retention pond is trying to drain. I have witnessed this happening may times
since moving in. Basically the retention pond becomes an extension of the swamp beyond it and does
not drain at the rate it is designed to drain at. Secondly, I have never actually seen the drainage hole on
the wall as the water has never been low enough, even when we went over a month without rain. In
this picture, the water was gurgling on the right side (swamp side) from the hole. But even when the
water is low, and the pond almost empty, I still cannot see the hole.
This brings me to another problem with the retention pond. The pond has filled with debris and dirt
after years of not being maintained. See below:
The pipe coming from my culvert is between 1/2 and 2/3 buried now. Basically, the retention pond has
lost significant capacity and has -possibly-partially covered the drainage holes on the overflow wall.
When I first observed the culvert being full in front of my house, I also observed this pipe completely
under water. This means that when the retention pond is full (which it stays more full given the current
situation) the water backs up into the drain pipe from the culvert, all of the way to the front of my yard.
The water trying to go into the culvert cannot simply flow into the culvert, down the drain and into the
retention pond because the culvert, pipe and pond is full. The water coming in will continue to backfill
until it has enough head pressure to slowly force water out of the retention pond, and through the
swamp, which it obviously cannot do.
This is the retention pond side of the overflow wall, no drain holes visible.
This image shows the retention pond. The bottom left is manicured and mowed and cared for, the
upper right is always full of water, is filling with trash, debris, and dirt, and is full of cattails. This portion
is the lowest portion of the pond and has been left unmaintained and needs to be dredged and repaired
back to its original condition.
The swamp: I wondered why in the world the water levels in the swamp remained so high. This is a
large area in which to take water. I knew that this area drained through another pipe along the sewer
line approximately 110 yards behind the retention pond. I walked back there this morning to see if
maybe this other pipe was clogged, or why so much water is always present back there. (side note, the
water level is always at the same level as the retention pond, again obscuring the drain hole and proving
that the retention pond is just an extension of the swamp rather than its own working system). This
morning I found the drainage pipe (top of the map above) to be working fine. However I through the
bushes I could hear a waterfall (upstream of the pipe) which was odd. So I moved the bushes to find
that the elevation of the swamp was actually much higher than the lowest point of the drain pipe,
several feet. This is due to a large beaver dam! Beavers took advantage of the skinny area in front of
the drainage pipe to build a large dam, shoring up the swamp and keeping constant water levels MUCH
higher than they should be.
The swam beyond the overflow wall, taken from the overflow wall.
Beaver dam and hole in front of the City's pipe out at the end of the swamp
The Big Picture/Summary
So if you step back and look at the big picture, this is a complex problem.
1. We have culverts up-street flowing into my culvert meanwhile overflowing and adding
significant additional water to the culvert at 4446
2. The culvert at 4446 backs up and the water is forced to flow against and around the surrounding
houses, with significant risk of flooding the interior
3. The culvert is becoming full and unable to take on more water because
4. It is already full from the culverts above, much less their overflow and
5. The retention pond is full because
6. The swamp is full just outside the overflow wall because
7. The swamp water is backing up against the overflow holes in the pond
8. To some degree because there is a huge beaver dam downstream from there
A side note for the City of College Station .. The overflow problem at the culvert will likely not be totally
fixed, even if the beaver dam is removed and the retention pond brought back up to par due to the fact
that the retention pond is designed to fill up in a rain event. Even though the retention pond would be
functioning correctly and draining at the right speed, it can still fill up causing the backup at the culvert.
The point of the side note here is that the overflow situation along Spring Meadows and Cold Springs
needs to be addressed as its own separate issue, despite the outcome of the retention pond and swamp
area .
I do not know exactly how to proceed with this. The retention pond is owned by the Spring Meadows
HOA. The property behind my house is all City of College Station property. The drainage in front of my
house is City of College Station Property. The culvert in front has problems, the retention pond has
problems, and the swamp has problems, all of which need to be addressed.
Please advise on how to proceed with this. I am concerned that the condition of the swamp and
retention pond will continue to deteriorate further complicating this problem. I am also concerned
about the performance of the drainage system along Spring Meadows, and the design capacity and
actual capacity of the culvert at 4446 Spring Meadows. All of these problems are currently working
towards and have almost succeeded at producing a flood event resulting in property damage of at least
two homes.
..
Please take the necessary action in a timely manner to find appropriate resolutions to this complex
problem. Please also keep me informed of the progress as I expect a timely response given the extent
to which the flooding is already occurring.
Thank you for your time and consideration.
Sincerely,
Travis Scott
4446 Spring Meadows
College Station, Texas 77845
979-450-0103
travis@oztotl.com
•Alan Gibbs
From: Chuck Gilman
Sent:
To:
Wednesday, November 06, 2013 3:19 PM
Alan Gibbs; Marshall Wallace
Cc: Jeffrey Given; Peter Caler; Donald Harmon
Subject: RE: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
Jeff Given is working up a response this w eek. We will get you a copy.
From: Alan Gibbs
Sent: Wednesday, November 06, 2013 2:37 PM
To: Chuck Gilman; Marshall Wallace
Cc: Jeffrey Given; Peter Caler; Donald Harmon
Subject: RE: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
I 'd like to get a copy of our response if it has gone out . Thanks .
Alan
From: Alan Gibbs
Sent: Monday, October 28, 2013 1:57 PM
To: Chuck Gilman; Marshall Wallace
Cc: Jeffrey Given; Peter Caler; Donald Harmon
Subject: RE: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
Looking at the drainage report the pipes appear to be sized to even convey the 100 yr (36" RCP at
0.28% = 36 CFS). The subject inlet may be undersized for larger storms especially if there is
drainage bypassi ng upstream inlets. Of course if there is any debris or blockage i n this storm
system (including the system closer to Fitch), most of the drainage will still flow down the
street to this ar ea. It would also obliviously help if there was an overflow swale above this
pipe to the pond with openings under the fence, etc .
From: Chuck Gilman
Sent: Monday, October 21, 2013 9:31 AM
To: Marshall Wallace; Alan Gibbs
Cc: Jeffrey Given; Peter Caler; Donald Harmon
Subject: RE: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
Thanks Marshall.
Jeff, when we are finished w it h t he drainage maintenance and a review of the drainage infrastructure plans,
will you please draft a response to Mr. Scott summarizing our findings and work we've completed
downstream of the pond?
From: Marshall Wallace
Sent: Monday, October 21, 2013 9:20 AM
To: Chuck Gilman; Alan Gibbs
Cc: Jeffrey Given; Peter Caler; Donald Harmon
Subject: RE : Drainage Concerns at Along Spring Meadows and Behind Neighborhood
We should be out there today or tomorrow
Marshall
1
-
' From: Chuck Gilman
Sent: Monday, October 21, 2013 9:16 AM
To: Alan Gibbs
Cc: Marshall Wallace; Jeffrey Given; Peter caler; Donald Harmon
Subject: RE: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
I think there is a combination of issues creating the problem .... the pond is not being maintained, and there is
some debris downstream of the pond on city property. I doubt that the inlet and storm sewers are
undersized; however, to prepare a thorough response, I thought we should at least take another look at the
plan set and confirm.
Please let us know if you find any information that suggests the drainage infrastructure is undersized.
Marshall noted last week that we have some drainage maintenance to perform downstream of the pond with
the menzi muck. Marshall, do you know when that work will be completed?
Thanks,
erg
From: Alan Gibbs
Sent: Friday, October 18, 2013 4:07 PM
To: Chuck Gilman
Cc: Marshall Wallace; Jeffrey Given; Peter caler; Donald Harmon
Subject: RE: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
Chuck,
I hadn't seen the memo. The final plat indicates the pond is a common area -private. The storm
sewer and inlets discharging to it are in drainage easements/ROW -public. I pulled the
development permit file from 2002 which has the drainage report, comments, etc -I'll review it
and see what I can find. Has the inlet, pipe, pond outfall been inspected for blockage, etc?
Alan
---·-----
From: Chuck Gilman
Sent: Thursday, October 17, 2013 1:47 PM
To: Alan Gibbs
Cc: Marshall Wallace; Jeffrey Given; Peter caler; Donald Harmon
Subject: FW: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
Alan, have you seen this memo? Any thoughts on the statement that the storm drains are undersized?
I assume there is just blockage in the detention pond that is creating a tail water that is causing water to rise
through our the system. However, given that this neighborhood is fairly new, I thought you may still have
review comments on this subdivision site plan in HTE.
From: Jeffrey Given
Sent: Wednesday, October 16, 2013 9:40 AM
To: Chuck Gilman
Subject: FW: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
2
See below and please read attachment...
---------------
From: Robert Sleeper
Sent: Wednesday, October 16, 2013 8: 11 AM
To: Jeffrey Given
Subject: FW: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
Jeff, I would like to get some info on this area
Thanks,
Robert
From: Travis Scott [mailto:travis@oztotl.com]
Sent: Tuesday, October 15, 2013 3:00 PM
To: Robert Sleeper; bod@springmeadowshoa.com
... _. __ ----·-----.,,. ... ___ -
Subject: Drainage Concerns at Along Spring Meadows and Behind Neighborhood
Mr. Sleeper and Spring Meadows HOA,
Attached is a PDF documenting the drainage situation along Spring Meadows and how it relates to the near-
miss flooding of two homes this past Sunday. Please review the document and let me know if you need more
information (full sized images, or anything else).
Mr. Sleeper of the City of College Station and I discussed meeting tomorrow (Wednesday) to discuss this issue
and look at the situation. I look forward to hearing from you in the morning to schedule a time. If anyone from
the HOA can meet tomorrow to look at this please let me know and I will inform you of the time and place.
I put together the attached document to explain the situation as I understand it and as I have witnessed it. Have
worked in retention pond engineering and modeling in the past, so I don't think I am too far from understanding
the situation.
Thank you all for being open to this concern. It has been a slight concern to me for a while, but my fears were
realized this past Sunday and actions need to be taken to prevent property damage. Thank you all for the help!
Sincerely,
Travis Scott
Travis@oztotl.com
979.450.0103 (cell)
3
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August 2, 2002
Mr. Spencer Thompson
1101 Texas Ave
College Station, Texas 77840
RE: Drainage Letter
Spring Meadows Subdivision
Dear Mr. Thompson,
I have attached a drainage report for referenced subdivision. The post development storm water
flows in essentially two directions. One area flows through storm sewer and outfalls in the creek
and the remaining drainage flows to a detention pond and is metered out through a circular weir
the predevelopment and post development storm water runoff from the referenced site
If you have any questions please contact me.
Very sincerely yours,
Municipal Development Group
Lenwood S. Adams, P.E.
Senior Project Manager
Executive Vice President
n _tJ ~:
siONE CWR er.
I 1 1
"-----+,..-.-1---..u_
\
8
11-1 ZIJNE /
EXHIBIT DRAWING 1
PRE-DEVELOPMENT
DRAINAGE AREAS
37.44 ACRES
SCALE: 1 .. = 1 oo·
ACREAGE BRfAKOOWN
Q) -11.24 ACRES 12> -26.20 ACRES
I , I' o/
M-1 ZONE /
EXHIBIT DRAWING 2
POST -DEVELOPMENT
DRAINAGE AREAS
33.24 :4fRES
SCALE: 1 = 1 oo'
CJ) -a.112 ACRES la -2.111 ACRES C) -12.211 ACRES
• -5.cJ7 ACRES 0 -5.11 ACRES
_,
Pre-Development
GENERAL INFORMATION
Description: Predevelopment Drainage Area 1
Drainage Area (APRE) = 11.240 acres
TIME OF CONCENTRATION (T J
GIVEN
Maximum Travel Distance (DPRJ
Composite Velocity
Composite Coeffcient of Runoff
1660 ft
ft 1.80 fsec
0.27
**NOTE: Minimum Tc allowed = 10 min.
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.806
65
8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.785
Coefficient (b) =
Coefficient (d) =
76
8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.763
Coefficient (b) =
Coefficient (d) =
80
8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.754
Coefficient (b) = 89
Coefficient (d) = 8.5
50 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745
Coefficient (b) =
Coefficient (d) =
98
8.5
100 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.73
96
8
RESULT
T C(PRE) = 15.37 min.
Rainfall Intensity (12) = 5.126 in/hr
•:e~:·5::.-.:·,·.; •••t•n• ·· : ,,.: ,:, :·:.·11;!1~·9r~·::-::'::,·:·
Rainfall Intensity (15) = 6.298 in/hr
.:,•.~, .. :,:.:, ..• ,·~ .. ' •. ',•.•,.·,;;;.·,•·.,•·.•,.•,•.·•,.·,•.'.•_:,•_.,'.·\., •. , •. ''·''·''''·''·''·''·''·.·'.·•.,.·,.·, .. ,··'.·.·.·'.:' .• ,.:, .•• • .. ···.,_••' ... :.·,·"'·'•_',·,.,·"'·· •1:9li72!'bt~H:t 9. :·:···:·:·:·:·:·:·:·:·:·>=·:::::::::::::::::::::::::;:;:·:·:·:··-:-·-:·
Rainfall Intensity (110) = 7.109 in/hr
.:•.,•.'ts·'·,•.,•,:.,·,'.'.,'1'.•,•0'.•.·.•.,•,•.,•,~.,',•.,',•.,',: .•• .. •.:•.-.•,•.:•.'.•.•.••. • • • '• • • ••• • •••••••• •aii1753 ht' .. i ? :: ~ •.•.•.•.•.•'.•'.•'.:;:~:~::;j:]:;:::::::~:;:~:: f 1~~~1~~~1~~~~~~~~~:t ::::::::::::::::::::::::::::::::::::::::::·:: .:·:·:::::::::::::::::::::'.::::::::::::·
Rainfall Intensity (125) = 8.137 i%r
::@~~:;: •• :•:, : J]Ji :::::•:• • :•.:]:•11;~91 ~t.~:: • ::
Rainfall Intensity (150) = 9.220 in/hr
'.l~~·:.5., •. :: :.:.'.·· '''l:::::••• ::::•••2!;~·~~:.9,ti.fJ?
Rainfall Intensity (1 100) = 9.619 i%r
•:R~:@:#: · .·J .• :•· •.:. t .'.••. .:: •· llf!~! 9t~::]•:
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
915102
Pre-Development
GENERAL INFORMATION
Description: Predevelopment Drainage Area 2
Drainage Area (APRE) = 26.200 acres
TIME OF CONCENTRATION CTJ
GIVEN
Maximum Travel Distance (DPRE)
Composite Velocity
Composite Coeffcient of Runoff
1780 ft
ft 2.00 lsec
0.30
**NOTE: Minimum Tc allowed = 1 O min.
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient (d) = 8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.785
Coefficient (b) = 76
Coefficient (d) = 8.5
10 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.763
80
8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.754
Coefficient (b) = 89
Coefficient (d) = 8.5
50 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745
Coefficient (b) = 98
Coefficient (d) = 8.5
100 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.73
96
8
RESULT
T C(PRE) = 14.8 min.
Rainfall Intensity (12) = 5.229 i%r
::e~:F::::::• :t,::::·::'.::.r::::I.: ::: <•i ::··: ··r···!!!ii~i:::e-r~H•••••t
Rainfall Intensity (15) = 6.419 i%r
·.:.GJ.:.'.·.~.'·.:.•~ .•. :,_::.•.•·· ::::•••• /). ::< ttJ? r 11 •••soli7ottM 1? ·--.·:·.·.·::::::::::::::::::::::::::::::::::::.:=:·:·:-:·:·:··-·.·.· .·.·.·.·.·.·.·.·.·-:-:-:-:;:;:;:;:;:;:;:;:;:;:;:;:;: .·.·.··:-:-;:;:;:;:;:;:;:;:;:;:;:·:·:·
Rainfall Intensity (1 10) = 7.241 in/hr
.
•.·,'_,_'·n··:.····_, .. , .. _,·,.,'1!,'_:_,,.o','.•,',•_,•,•_,~,'_,•,:_,•,:_,•,:_,•,•_,•,•_,•,•_,•,•_,•,• >• , , : •••.•• •• • •t.•s.·•_·,_7_:'.:.l.3_' .. '.'8_.,_.'_8_.,_.,_,•.•:.e.·:i_s.·'.J •-••.••.•.•.•'_, ~ ========================:=rnmj1t:::::::::::================= =====:::::::::::::==== ==:=:=:=:=:::============ ::::~~~~::::::=:
Rainfall Intensity (1 25) = 8.287 in/hr
==g :::::::=:=:=:====:========================== =·=·=·=·=·=·= :;:·:·:·===·=·=·=·=·=·= =j~1~[~1~i~[~f~!~f&&~i.8.b1~]iCtS ~[~~t[~~~~~~j t:M:FtJ:J • tt.!!?\!? ,,,,,,,,, ... w ... ,,.,.,., ,,,
Rainfall Intensity (1 50) = 9.387 in/hr
',,•.et,.'_.-,::_.·,.-_.·,.·.·· ...... '.•.'_,._··.·_,'.',•'.:','.~,-.',·.•.' .. :_:_ •. ,._,',.•_,',,._,,,,: .•,•.',•.•,•.•. •m..••.••.•.•,•.•,•.•,•.•,•.',• :: :: ::: .,,,... •'Hti.lioo:mti··,•.•,·.•·,•.•,•.•,• ... ,'.'.·_, !OP~ {{:~:)}~{:~ :-:::::::::::::::::::::::::::::::::::: .·.·.·.·.·'.·.·.·,·:::::::::·
Rainfall Intensity (1100) = 9.794 in/hr
•.:_n_._'.•.•.•.''.~.•0:::0'.•.•.•.1=.·.•.•.•.'.•.•.•.•.•.•.••.••.••.:: t /t , J ?.••.••.••.••'.••.•• .. ••.••.••.i.••.••.••.••.••.••.••.'~.: .• ~.:_, .• ,~_-··.··iij~.· ·.·•.••.c.·•.·'.~.~-·•.•• '"'.,.. ~=· :1:=:".J:=~==~e:!.=-=·=·=Ji~t=:::~'.~~~~~r
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
915102
Post-Development
GENERAL INFORMATION
Description: Drainage Basin Postdevelopment.
Drainage Area (1) = 8.620 acres
Drainage Area (2) =
Drainage Area (3) =
Drainage Area (4) =
Drainage Area (5) =
Total
Velocity of Runoff (V1) =
Coefficient of Runoff (C1) =
Velocity of Runoff (ViJ =
Coefficient of Runoff (CiJ =
Velocity of Runoff (V3) =
Coefficient of Runoff (C3) =
Velocity of Runoff (V 4) =
Coefficient of Runoff (C4)=
Velocity of Runoff (Vs) =
Coefficient of Runoff (Cs) =
Area 1.2 & 5
Total Area
Composite Velocity
Composite Coeffcient of Runoff
Composite Time of Concentration
Area 3 & 4
Total Area
Composite Velocity
Composite Coeffcient of Runoff
Composite Time of Concentration
2.070 acres
12.290 acres
5.070 acres
5.190 acres
33.240 acres
8.50 ft/sec
0.60
8.70 ft'••<
0.60
8.60 ft/sec
0.60
8.60 ft'••<
0.60
8.00 ft'••<
0.60
15.88 acres
8.36 ft/sec
0.60
10.00 min
17.36 acres
8.60 ft/sec
0.60
10.00 min
••NOTE: Minimum Tc allowed= 10 min.
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient (d) = 8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.785
76
8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.763
80
8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.754
Coefficient (b) = 89
Coefficient (d) = 8.5
50 YEAR FREQUENCY RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.745
98
8.5
100 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.73
Coefficient (b) = 96
Coefficient (d) = 8
RESULT (Area 1,2 & 5)
Rainfall Intensity (liJ = 6.327 in/1v
?if: JJ ?' : : t:\ i@ ~~l.t~M~W JJ
Rainfall Intensity Os) = 7.693 in/1v
•P.i#t :/ 'Tit?? :::::· •:t t~l.J.M!\#K'
Rainfall Intensity (110) = 8.635 tn/1v
~in'" :.]\\ \] • •••It taajj~~·M; ==:
Rainfall Intensity (12s) = 9.861 tn/1v
:•,..,.,·,·,·.·,·=.'.'.'=_•,_•=·_#_·· •. •.· .. •.·.•.·.•,••, .............. · · · •?? •••:::=•? .•.•.•·.•.•.•.•.•· .•. •.•.•.s.·•-~ ... _••.1_:_·_•.=.i.•.·.·.·.~.·.·.·.:: . .-_ •..• ·.c.'.'.·.J!.·_·.s..'.=.•.•.•.•.••.:.•:.: :~ ~~\~?~t:/~~~ ::::::::::::::::·:·:·:· ·.·
Rainfall Intensity Oso) = 11 .148 in/1v
·~~] I ] r •• • • MPt.dM ~mt@
Rainfall Intensity (1100) = 11 .639 in/1v
§\\Mil ::•:::== •••• ••••• '•••MMl.~!•:•M~ >••
RESULT (Area 3 & 4)
Rainfall Intensity (liJ = 6.327 in/1v
t!i# \ >•••' •=::••••• •• ••••••M~~N!:~ J\J
Rainfall Intensity (Is) = 7.693 in/1v
·~··~\\\\\ • ? : : tt ? Ml.t~~ M¥ ?
Rainfall Intensity (110) = 8.635 in/1v
\9.\W\J \ ::: •• ///JJ\: \r ::rn~*'=MWt@ t
Rainfall Intensity (12s) = 9.861 in/1v
J¥@ •::::: • •• • :: #M!¥M \4@ ?
Rainfall Intensity Osol = 11 .148 in/1v
:pl!@{ : ::::: :: •. =·::: /}:: Mh9M :~WJ?
Rainfall Intensity (1100) = 11 .639 in/1v
:§.l!ii\!tt···::. • :::t ,,;::•:,/1~e~M::MiV•
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
9/5/02
Post-Development (Area 1, 2 & 5) Pre-Development (Area 1)
2 YEAR 5 YEAR 10 YEAR
0 0 0 0 0 0 0
10 60.781 15.686 73.908 19.272 82.955 21 .753
20 30.391 7.843 36.954 9.636 41 .478 10.877
30 0 0.000 0 0.000 0 0.000
VOL = 40586 49172 55082
25 YEAR 50 YEAR 100 YEAR
0 0 0 0 0 0 0
10 94.743 24.901 107.100 28.214 111.822 29.436
20 47.372 12.451 53.550 14.107 55.911 14.718
30 0 0.000 0 0.000 0 0.000
VOL= 62858 70998 74147
2-Year Hydrograph 5-Year Hydrograph
c;;-80 -r----....-----.---.... .... ~ 60 +----~---t----t
Q) e> 40 11' "5 20
5 0
0 10 20
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
30
~ 80 ......---....-----.------.
D Post-
Development
D Pre-Development
~ 60 -+----
Q) e> 40 11' "5 20
(/) c 0
0 10 20
Time (min)
Project Manager: Lee Adams
Calculations: Mark Taylor
30
Ill Post-
Development
D Pre-Development
915102
en 100 .... ~ 80
Q) 60 Cl ...
10-Year Hydrograph
rn Post-
Development
25-Year Hydrograph
~ 100 -..----........----.-----.
~ 80 +-----
~ 60
0 Post-
Development
40 ca .r:. D Pre-Development :; 40 -r---7.:;:;:;:;:;:
£ 20
D Pre-Development
20 u .!.1 0 c
0 10 20 30
Time (min)
50-Year Hydrograph
en 150 .... u -0 Post-
Q) 100 Cl Development ...
(/)
i5 0
~ 150 u -Q) 100 Cl ...
0 10 20 30
Time (min)
100-Year Hydrograph
rn Post-
Development
ca 50 .r:. D Pre-Development ca 50 .r:. D Pre-Development
u (/)
i5 0
0 10 20
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
30
u
Ill
i5 0
0 10 20
Time (min)
Project Manager: Lee Adams
Calculations: Mark Taylor
30
915102
Post-Development (Area 3 & 4) Pre-Development (Area 2)
2YEAR 5YEAR 10 YEAR
0 0 0 0 0 0 0
10 66.446 41.442 80.796 50.870 90.687 57.388
20 33.223 20.721 40.398 25.435 45.343 28.694
30 0 0.000 0 0.000 0 0.000
VOL= 22503 26933 29968
25 YEAR 50YEAR 100 YEAR
0 0 0 0 0 0 0
10 103.573 65.680 117.081 74.400 122.244 77.626
20 51 .787 32.840 58.541 37.200 61 .122 38.813
30 0 0.000 0 0.000 0 0.000
VOL= 34104 38413 40156
2-Year Hydrograph 5-Year Hydrograph
~ 80 ~--~--~--~
u -60 -t---
Q)
El 40 11' "fi 20
(/) c 0
0 10 20
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
30
13 Post-
Development
(ii 100 ~--~--~-~ .... ~ 80 -i---+«-----+-----<
~ 60 -+---
:;; 40 ~ 13 Pre-Development
u 20 ~ o-i&llifil]jj$£Llfilllilli;r&t:li:~
0 10 20
Time (min)
Project Manager: Lee Adams
Calculations: Mark Taylor
30
rn Post-
Development
D Pre-Development
915102
:E' 100
u 80 -Cl) 60 Cl ...
10-Year Hydrograph
rn Post-
Development
25-Year Hydrograph
:E' 150 -,.-----.....----.------.
~
Cl) 100 +---
Cl ...
rn Post-
Development
40 IU .c: El Pre-Development ~ 50 El Pre-Development
20 u
Ill
i:S 0
0 10 20 30
Time (min)
50-Year Hydrograph
-150 :? ~ rn Post-
Cl) 100 Cl Development ...
u i5 0
:E' 150
~
Cl) 100
Cl ...
0 10 20 30
Time (min)
100-Year Hydrograph
rn Post-
Development
IU 50 .c: El Pre-Development IU 50 .c: El Pre-Development
u
Ill
i:S 0
0 10 20
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
30
u Ill
c 0
0 10 20
Time (min)
Project Manager: Lee Adams
Calculations: Mark Taylor
30
9/5/02
Time
Post-Development Area 1,2 &5
Inflow Hydrograph Ordinates
(Cubic Feet per Second)
2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
(min) Storm Storm Storm Storm Storm Storm
0 0 0 0 0 0 0
1 6.08 7.39 8.30 9.47 10.71 11.18
2 12.16 14.78 16.59 18.95 21.42 22.36
3 18.23 22.17 24.89 28.42 32.13 33.55
4 24.31 29.56 33.18 37.90 42.84 44.73
5 30.39 36.95 41 .48 47.37 53.55 55.91
6 36.47 44.34 49.77 56.85 64.26 67.09
7 42.55 51.74 58.07 66.32 74.97 78.28
8 48.62 59.13 66.36 75.79 85.68 89.46
9 54.70 66.52 74.66 85.27 96.39 100.64
==:: ,:: 11:91:::: :::::]: ::: ~mitt~: ... :::i ijiz?:;~1,,,:: ::,1J:~gma t> ::::::i4i?4::::::::: ::rn pvMn : : rn::1:~:~~~::::::::
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
57.74 70.21 78.81 90.01 101 .75 106.23
54.70 66.52 74.66 85.27 96.39 100.64
51 .66 62.82 70.51 80.53 91.04 95.05
48.62 59.13 66.36 75. 79 85.68 89.46
45.59 55.43 62.22 71.06 80.33 83.87
42.55 51.74 58.07 66.32 74.97 78.28
39.51 48.04 53.92 61 .58 69.62 72.68
36.47 44.34 49.77 56.85 64.26 67.09
33.43 40.65 45.63 52.11 58.91 61 .50
30.39 36.95 41 .48 47.37 53.55 55.91
27.35 33.26 37.33 42.63 48.20 50.32
24.31 29.56 33.18 37.90 42.84 44.73
21 .27 25.87 29.03 33.16 37.49 39.14
18.23 22.17 24.89 28.42 32.13 33.55
15.20 18.48 20.74 23.69 26.78 27.96
12.16 14.78 16.59 18.95 21.42 22.36
9.12 11 .09 12.44 14.21 16.07 16.77
6.08 7.39 8.30 9.47 10.71 11 .18
3.04 3.70 4.15 4.74 5.35 5.59
0 0 0 0 0 0
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
915102
Time
Pre-Development Area 1
Outflow Hydrograph Ordinates
(Cubic Feet per Second)
2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
(min) Storm Storm Storm Storm Storm Storm
0 0 0 0 0 0 0
1 1.57 1.93 2.18 2.49 2.82 2.94
2 3.14 3.85 4.35 4.98 5.64 5.89
3 4.71 5.78 6.53 7.47 8.46 8.83
4 6.27 7.71 8.70 9.96 11.29 11 .77
5 7.84 9.64 10.88 12.45 14.11 14.72
6 9.41 11.56 13.05 14.94 16.93 17.66
7 10.98 13.49 15.23 17.43 19.75 20.61
8 12.55 15.42 17.40 19.92 22.57 23.55
9 14.1 2 17 .34 19.58 22 .41 25.39 26.49
,,, ::J:::1:~i;::::: :::::=:::::: = rn:~;~~ :]: : 1g:;g;:=::r .::::::;?1:;~§: :::::::::::gM~9: ::,::::::::::1~.;?1t:::::t:::::gg;!!:::::::::::
11 14.90 18.31 20.67 23.66 26.80 27.96
12 14.12 17.34 19.58 22.41 25.39 26.49
13 13.33 16.38 18.49 21.17 23 .98 25.02
14 12.55 15.42 17.40 19.92 22 .57 23 .55
15 11 .76 14.45 16.31 18.68 21 .16 22.08
16 10.98 13.49 15.23 17.43 19.75 20 .61
17 10.20 12.53 14.14 16.19 18.34 19.13
18 9.41 11.56 13.05 14.94 16.93 17.66
19 8.63 10.60 11.96 13.70 15.52 16.19
20 7.84 9.64 10.88 12.45 14.11 14.72
21 7.06 8.67 9.79 11 .21 12.70 13.25
22 6.27 7.71 8.70 9.96 11 .29 11 .77
23 5.49 6.75 7.61 8.72 9.87 10.30
24 4.71 5.78 6.53 7.47 8.46 8.83
25 3.92 4.82 5.44 6.23 7.05 7.36
26 3.14 3.85 4.35 4.98 5.64 5.89
27 2.35 2.89 3.26 3.74 4.23 4.42
28 1.57 1.93 2.18 2.49 2.82 2.94
29 0.78 0.96 1.09 1.25 1.41 1.47
30 0 0 0 0 0 0
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
915102
Channel
Depth vs. Volume
Elevation Depth Volume
(ft) (ft) (cf)
247.0 0.0 0.00
247.5 0.5 5579.32
248 .0 1.0 11158.65
248.5 1.5 16737.97
249.0 2.0 22317.29
249.5 2.5 27896.61
250.0 3.0 33475.94
250.5 3.5 39055.26
251.0 4.0 44634.58
251.5 4.5 50213.90
252.0 5.0 55793.23
252.5 5.5 61372.55
253.0
253.5
254 .0
254.5
255.0
6.0
6.5
7.0
7.5
8.0
66951 .87
72531 .19
78110.52
83689.84
89269.16
Channel Depth vs. Volume
9.0
8.0
7.0 -6.0 = 5.0 -J: 4.0 -c. 3.0 Q) c 2.0
1.0
0.0
v : 9E-05x -1 E-07
/""
~
~ ~
~
~ ~
~
~
~
-1.0 ---·-·------.__ ---·----------1v--
Volume (cf)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
00
9/5/02
Depth vs. Discharge
9.0 -.----------.----\-ir--++--if:~---+-¥--------=~~,___-...,.------r------,
8.0 -f-----+-----+-----+--------l-----+-----------,.-+----1
7.0 +----~---+----+------1------+--~--t----------1
~ 6.0 -+----+----+----+------1-----+-cl----t----;
~ ...._...
.c: 5.0
~ c. 4.0 -+----+----+----+------1~,__---+----t----;
Cl) c 3.0 -+----+----+----+--~~'------+----+----1
2.0 -t--~---+----+----7'-----11------t------+--------J
1.0 -+----+----+---~-----1f-------+-----t------l
0.0 -+------+----+----+------!i--------+-----+-------1
0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0
Discharge (cfs)
Depth
(ft)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
35.0
~ 30.0
~ 25.0
8, 20.0
~ 15.0 ..c: (.) 10.0 If) c 5.0
0.0
Storage Indication
Storage Discharge 2s/t 2s/t+O
(cf) (cfs) (cfs) (cfs)
0.00 0.00 0.00 0.00
5579.32 12.30 185.98 198.28
11158.65 14.11 371 .96 386.06
16737.97 15.71 557.93 573 .64
22317.29 17.16 743.91 761 .07
27896.61 18.50 929.89 948.39
33475.94 19.75 1115.86 1135.61
39055.26 20.92 1301 .84 1322.76
44634.58 22.03 1487.82 1509.85
50213.90 23.09 1673.80 1696.88
55793.23 24.10 1859.77 1883.87
61372.55 25.07 2045.75 2070.82
66951 .87 26.00 2231 .73 2257.73
72531 .19 26.91 2417.71 2444.61
78110.52 27 .78 2603.68 2631.46
83689.84 28.63 2789.66 2818.29
89269.16 29.45 2975.64 3005.09
Discharge vs. 2s/t+O
~ ---------.......
~
I
I
0.0 500.0 1000.0 1500.0 2000.0 2500.0 3000.0 3500.0
2s/t+O (cfs)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
915102
Inflow I Outflow Simulation
2-Year Storm Event
Time Inflow Volume 2s/t-0 2s/t+O Outflow Depth
(min) (cfs) (cf) (cfs) (cfs) (cfs) (ft)
0 0.00 0.00 0.00 0.00 0.00 0.00
1 6.08 364.69 11.35 12.96 0.81 0.03
2 12.16 1458.74 45.39 51 .86 3.23 0.13
3 18.23 3282.17 102.13 116.68 7.28 0.30
4 24.31 5834.98 181.56 207.43 12.93 0.53
5 30.39 9117.15 289.27 318.54 14.63 0.82
6 36.47 13128.70 422.21 453.04 15.42 1.18
7 42.55 17869.61 579.31 612.00 16.34 1.61
8 48.62 23339.90 760.59 795.41 17.41 2.10
9 54.70 29539.57 966.03 1003.27 18.62 2.66
10 60.78 36468.60 1195.65 1235.59 19.97 3.28
11 57.74 38109.69 1250.03 1290.61 20.29 3.43
12 54.70 39386.09 1292.33 1333.41 20.54 3.54
13 51 .66 40297.80 1322.54 1363.98 20.72 3.63
14 48.62 40844.83 1340.67 1382.32 20.83 3.68
15 45.59 41027.18 1346.71 1388.43 20.86 3.69
16 42.55 40844.83 1340.67 1382.32 20.83 3.68
17 39.51 40297.80 1322.54 1363.98 20.72 3.63
18 36.47 39386.09 1292.33 1333.41 20.54 3.54
19 33.43 38109.69 1250.03 1290.61 20.29 3.43
20 30.39 36468.60 1195.65 1235.59 19.97 3.28
21 27.35 34462.83 1129.18 1168.34 19.58 3.10
22 24.31 32092.37 1050.63 1088.86 19.12 2.89
23 21 .27 29357.22 959.99 997.16 18.58 2.64
24 18.23 26257.39 857.27 893.23 17.98 2.36
25 15.20 22792.88 742.46 777.07 17.30 2.05
26 12.16 18963.67 615.57 648.68 16.56 1.71
27 9.12 14769.78 476.59 508.06 15.74 1.33
28 6.08 10211 .21 325.53 355.22 14.85 0.92
29 3.04 5287.95 162.38 190.15 13.89 0.48
30 0.00 0.00 -12.85 12.85 12.85 0.00
Inflow/Outflow Simulation
2-Year Storm Event
80.00
iii ~ 60.00
Cl) D Inflow ~ 40.00 OOutflow ~ 20.00
u::: 0.00
0 5 10 15 20 25 30
Tlme (mln)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.03 0.66
247.13 2.66
247.30 5.98
247.53 10.63
247.82 12.02
248.18 12.66
248.61 13.42
249.10 14.30
249.66 15.29
250.28 16.41
250.43 16.67
250.54 16.87
250.63 17.02
250.68 17.11
250.69 17.14
250.68 17.11
250.63 17.02
250.54 16.87
250.43 16.67
250.28 16.41
250.10 16.08
249.89 15.70
249.64 15.27
249.36 14.77
249.05 14.21
248.71 13.60
248.33 12.93
247.92 12.20
247.48 11.41
247.00 10.56
915102
Inflow I Outflow Simulation
5-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow Depth
(min) (cfs) (cf) (cfs) (cfs) (cfs) (ft)
0 0.00 0.00 0.00 0.00 0.00 0.00
1 7.39 443.45 13.80 15.76 0.98 0.04
2 14.78 1773.79 55.19 63.06 3.93 0.16
3 22.17 3991.03 124.19 141.88 8.85 0.36
4 29.56 7095.17 222.27 250.75 14.24 0.64
5 36.95 11086.20 354.52 384.56 15.02 1.00
6 44.34 15964.13 516.17 548.11 15.97 1.44
7 51 .74 21728.95 707.20 741.39 17.10 1.96
8 59.13 28380.67 927.63 964.42 18.39 2.55
9 66.52 35919.29 1177.45 1217.17 19.86 3.23
10 73.91 44344.80 1456.65 1499.67 21 .51 3.99
11 70.21 46340.32 1522.78 1566.58 21 .90 4.17
12 66.52 47892.38 1574.21 1618.61 22.20 4.31
13 62.82 49001 .00 1610.95 1655.78 22.42 4.41
14 59.13 49666.18 1632.99 1678.09 22.55 4.47
15 55.43 49887.90 1640.34 1685.52 22.59 4.49
16 51 .74 49666.18 1632.99 1678.09 22.55 4.47
17 48.04 49001.00 1610.95 1655.78 22.42 4.41
18 44.34 47892.38 1574.21 1618.61 22.20 4.31
19 40.65 46340.32 1522.78 1566.58 21 .90 4.17
20 36.95 44344.80 1456.65 1499.67 21 .51 3.99
21 33.26 41905.84 1375.83 1417.89 21.03 3.77
22 29.56 39023.42 1280.31 1321.25 20.47 3.51
23 25.87 35697.56 1170.10 1209.74 19.82 3.21
24 22.17 31928.26 1045.19 1083.36 19.09 2.87
25 18.48 27715.50 905.59 942.11 18.26 2.49
26 14.78 23059.30 751.29 786.00 17.35 2.08
27 11.09 17959.64 582.30 615.01 16.36 1.62
28 7.39 12416.54 398.61 429.16 15.28 1.12
29 3.70 6430.00 200.22 228.44 14.11 0.58
30 0.00 0.00 -12.85 12.85 12.85 0.00
Inflow/Outflow Simulation
5-Year Storm Event
80.00
E" .!:!. 60.00
Cll D Inflow ~ 40.00
Cl Outflow ~ 20.00 u::
0.00
0 5 10 15 20 25 30
Time(mln)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.04 0.81
247.16 3.23
247.36 7.27
247.64 11 .70
248.00 12.34
248.44 13.12
248.96 14.04
249.55 15.11
250.23 16.32
250.99 17.67
251 .17 17.99
251 .31 18.24
251.41 18.41
251.47 18.52
251.49 18.56
251.47 18.52
251.41 18.41
251 .31 18.24
251 .17 17.99
250.99 17.67
250.77 17.28
250.51 16.81
250.21 16.28
249.87 15.68
249.49 15.00
249.08 14.26
248.62 13.44
248.12 12.55
247.58 11.59
247.00 10.56
915102
Inflow I Outflow Simulation
10-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow Depth
(min) (cfs) (ct) (cfs) (cfs) (cfs) (ft)
0 0.00 0.00 0.00 0.00 0.00 0.00
1 8.30 497.73 15.49 17.69 1.10 0.04
2 16.59 1990.92 61 .95 70.78 4.41 0.18
3 24.89 4479.57 139.39 159.25 9.93 0.40
4 33.18 7963.68 251 .05 279.87 14.41 0.72
5 41.48 12443.25 399.49 430.06 15.28 1.12
6 49.77 17918.28 580.92 613.63 16.35 1.61
7 58.07 24388.77 795.34 830.57 17.61 2.19
8 66.36 31854.72 1042.75 1080.90 19.07 2.87
9 74.66 40316.13 1323.15 1364.59 20.72 3.63
10 82.96 49773.00 1636.53 1681 .67 22.57 4.48
11 78.81 52012.79 1710.75 1756.76 23.00 4.68
12 74.66 53754.84 1768.48 1815.17 23.34 4.84
13 70.51 54999.17 1809.72 1856.89 23.59 4.95
14 66.36 55745.76 1834.46 1881 .93 23.73 5.02
15 62.22 55994.63 1842. 71 1890.27 23.78 5.04
16 58.07 55745.76 1834.46 1881 .93 23.73 5.02
17 53.92 54999.17 1809.72 1856.89 23.59 4.95
18 49.77 53754.84 1768.48 1815.17 23.34 4.84
19 45.63 52012.79 1710.75 1756.76 23.00 4.68
20 41.48 49773.00 1636.53 1681 .67 22.57 4.48
21 37.33 47035.49 1545.82 1589.88 22.03 4.23
22 33.18 43800.24 1438.61 1481 .41 21.40 3.94
23 29.03 40067.27 1314.90 1356.25 20.67 3.61
24 24.89 35836.56 1174.70 1214.40 19.85 3.23
25 20.74 31108.12 1018.01 1055.86 18.93 2.80
26 16.59 25881 .96 844.83 880.64 17.91 2.33
27 12.44 20158.06 655.15 688 .72 16.79 1.81
28 8.30 13936.44 448.97 480.12 15.57 1.25
29 4.15 7217.08 226.31 254.83 14.26 0.65
30 0.00 0.00 -12.85 12.85 12.85 0.00
Inflow/Outflow Simulation
10-Year Storm Event
100.00 u; 80.00 -~ 60.00 .S! l'!! 40.00 ~ 0 20.00 -u::
0.00
0 5 10 15
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
20
Dlnflow
DOutflow
25 30
Project Manager: Lee Adams
Calculations: Mark Taylor
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.04 0.91
247.18 3.63
247.40 8.16
247.72 11.84
248.12 12.55
248.61 13.43
249.19 14.47
249.87 15.67
250.63 17.02
251.48 18.54
251.68 18.90
251.84 19.18
251 .95 19.38
252.02 19.50
252.04 19.54
252.02 19.50
251.95 19.38
251 .84 19.18
251.68 18.90
251.48 18.54
251 .23 18.10
250.94 17.58
250.61 16.98
250.23 16.30
249.80 15.55
249.33 14.71
248.81 13.79
248.25 12.79
247.65 11.72
247.00 10.56
9/5/02
Inflow I Outflow Simulation
25-Year Storm Event
Time Inflow Volume 2s/t-0 2s/t+O Outflow Depth
(min) (cfs) (cf) (cfs) (cfs) (cfs) (ft)
0 0.00 0.00 0.00 0.00 0.00 0.00
1 9.47 568.46 17.69 20.21 1.26 0.05
2 18.95 2273.83 70.75 80.84 5.04 0.20
3 28.42 5116.12 159.20 181.88 11 .34 0.46
4 37.90 9095.33 288.55 317.81 14.63 0.82
5 47.37 14211.45 458.09 489.34 15.63 1.28
6 56.85 20464.49 665.30 699.00 16.85 1.84
7 66.32 27854.44 910.19 946.77 18.29 2.51
8 75.79 36381.31 1192.76 1232.66 19.95 3.27
9 85.27 46045.10 1513.00 1556.68 21 .84 4.14
10 94.74 56845.80 1870.91 1918.81 23.95 5.12
11 90.01 59403.86 1955.68 2004.58 24.45 5.35
12 85.27 61393.46 2021 .61 2071 .28 24.84 5.53
13 80.53 62814.61 2068.71 2118.93 25.11 5.65
14 75.79 63667.30 2096.96 2147.52 25.28 5.73
15 71 .06 63951 .53 2106.38 2157.05 25.33 5.76
16 66.32 63667.30 2096.96 2147.52 25.28 5.73
17 61 .58 62814.61 2068.71 2118.93 25.11 5.65
18 56.85 61393.46 2021.61 2071 .28 24.84 5.53
19 52.11 59403.86 1955.68 2004.58 24.45 5.35
20 47.37 56845.80 1870.91 1918.81 23.95 5.12
21 42.63 53719.28 1767.30 1813.98 23.34 4.83
22 37.90 50024.30 1644.86 1690.09 22.62 4.50
23 33.16 45760.87 1503.58 1547.15 21 .78 4.12
24 28.42 40928.98 1343.46 1385.14 20.84 3.68
25 23.69 35528.63 1164.50 1204.08 19.79 3.20
26 18.95 29559.82 966.70 1003.95 18.62 2.66
27 14.21 23022.55 750.07 784.77 17.35 2.07
28 9.47 15916.82 514.60 546.52 15.96 1.43
29 4.74 8242.64 260.29 289.22 14.46 0.74
30 0.00 0.00 -12.85 12.85 12.85 0.00
Inflow/Outflow Simulation
25-Year Storm Event
100.00
VI 80.00 -~ 60.00 -~ ~ 40.00 ;:
0 20.00 u:::
0.00
0 5 10 15
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
20
Dlnflow
DOutflow
25 30
Project Manager: Lee Adams
Calculations: Mark Taylor
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.05 1.04
247.20 4.14
247.46 9.32
247.82 12.02
248.28 12.84
248.84 13.84
249.51 15.02
250.27 16.39
251.14 17.94
252.12 19.67
252.35 20.08
252.53 20.40
252.65 20.63
252.73 20.77
252.76 20.81
252.73 20.77
252.65 20.63
252.53 20.40
252.35 20.08
252.12 19.67
251 .83 19.17
251 .50 18.58
251 .12 17.89
250.68 17.12
250.20 16.25
249.66 15.30
249.07 14.25
248.43 13.11
247.74 11 .88
247.00 10.56
915102
Time
(min)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
~
Inflow I Outflow Simulation
50-Year Storm Event
Inflow
(cfs)
0.00
10.71
21.42
32.13
42.84
53.55
64.26
74.97
85.68
96.39
107.10
101 .75
96.39
91 .04
85.68
80.33
74.97
69.62
64.26
58.91
53.55
48.20
42.84
37.49
32.13
26.78
21.42
16.07
10.71
5.35
0.00
Volume
(cf)
0.00
642.60
2570.40
5783.40
10281 .60
16065.00
23133.60
31487.40
41 126.40
52050.60
64260.00
67151 .70
69400.80
71007.30
71971 .20
72292.50
71971 .20
71007.30
69400.80
67151 .70
64260.00
60725.70
56548.80
51729.30
46267.20
40162.50
33415.20
26025.30
17992.80
9317.70
0.00
2s/t-0
(cfs)
0.00
20.00
79.98
179.96
327.86
519.51
753.75
1030.58
1350.00
1712.01
2116.61
2212.43
2286.96
2340.20
2372.14
2382.79
2372.14
2340.20
2286.96
2212.43
2116.61
1999.48
1861.07
1701.36
1520.36
1318.06
1094.46
849.58
583.39
295.92
-12.85
2s/t+O
(cfs)
0.00
22.84
91 .38
205.60
357.58
551.49
788.49
1068.58
1391 .76
1758.03
2167.39
2264.35
2339.76
2393.62
2425.94
2436.71
2425.94
2393.62
2339.76
2264.35
2167.39
2048.90
1908.85
1747.26
1564.12
1359.44
1133.22
885.44
616.13
325.26
12.85
Inflow/Outflow Simulation
50-Year Storm Event
Outflow
(cfs)
0.00
1.42
5.70
12.82
14.86
15.99
17.37
19.00
20.88
23.01
25.39
25.96
26.40
26.71
26.90
26.96
26.90
26.71
26.40
25.96
25.39
24.71
23.89
22.95
21 .88
20.69
19.38
17.93
16.37
14.67
12.85
Depth
(ft)
0.00
0.06
0.23
0.52
0.93
1.45
2.08
2.83
3.70
4.68
5.78
6.04
6.25
6.39
6.48
6 .51
6.48
6.39
6.25
6.04
5.78
5.47
5.09
4.66
4.16
3.61
3.01
2.34
1.62
0.84
0.00
i 100.00 -t--+---D Inflow
D Outflow l!! ~ 50.00 -I--/.
u:::
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Elevation
(ft)
247.00
247.06
247.23
247.52
247.93
248.45
249.08
249.83
250.70
251 .68
252.78
253.04
253.25
253.39
253.48
253.51
253.48
253.39
253.25
253.04
252.78
252.47
252.09
251 .66
251 .16
250.61
250.01
249.34
248.62
247.84
247.00
Velocity
(ft/sec)
0.00
1.17
4.68
10.53
12.21
13.13
14.27
15.61
17.15
18.90
20.86
21 .32
21.68
21 .94
22.10
22.15
22.10
21 .94
21.68
21 .32
20.86
20.29
19.62
18.85
17.98
17.00
15.92
14.73
13.44
12.05
10.56
915102
Inflow I Outflow Simulation
100-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow Depth
(min) (cfs) (cf) (cfs) (cfs) (cfs) (ft)
0 0.00 0.00 0.00 0.00 0.00 0.00
1 11 .18 670.93 20.88 23.85 1.49 0.06
2 22.36 2683.73 83.51 95.41 5.95 0.24
3 33.55 6038.39 187.89 214.67 13.39 0.54
4 44.73 10734.91 342.88 372.78 14.95 0.97
5 55.91 16773.30 542.98 575.24 16.13 1.51
6 67.09 24153.55 787.55 822.69 17.57 2.17
7 78.28 32875.67 1076.59 1115.13 19.27 2.96
8 89.46 42939.65 1410.09 1452.56 21.23 3.86
9 100.64 54345.49 1788.06 1834.98 23.46 4.89
10 111 .82 67093.20 2210.49 2262.39 25.95 6.04
11 106.23 70112.39 2310.54 2363.62 26.54 6.31
12 100.64 72460.66 2388.36 2442.35 27.00 6.52
13 95 .05 74137.99 2443.94 2498.59 27.32 6.67
14 89.46 75144.38 2477.29 2532.33 27.52 6.76
15 83.87 75479.85 2488.41 2543.58 27.58 6.79
16 78.28 75144.38 2477.29 2532.33 27.52 6.76
17 72.68 74137.99 2443.94 2498.59 27.32 6.67
18 67.09 72460.66 2388.36 2442.35 27.00 6.52
19 61 .50 70112.39 2310.54 2363.62 26.54 6.31
20 55.91 67093.20 2210.49 2262.39 25.95 6.04
21 50.32 63403.07 2088.21 2138.66 25.23 5.71
22 44.73 59042.02 1943.69 1992.44 24.38 5.31
23 39.14 54010.03 1776.94 1823.73 23.39 4.86
24 33.55 48307.10 1587.96 1632.52 22.28 4.35
25 27.96 41933.25 1376.74 1418.81 21.04 3.77
26 22.36 34888.46 1143.29 1182.61 19.66 3.14
27 16.77 27172.75 887.60 923.92 18.16 2.45
28 11 .18 18786.10 609.68 642.72 16.52 1.69
29 5.59 9728.51 309.53 339.04 14.75 0.88
30 0.00 0.00 -12.85 12.85 12.85 0.00
Inflow/Outflow Simulation
100-Year Storm Event
150.00
VI --;-100.00
~ 50.00 ~ 0 u::
0.00
0 5 10 15
Time(min)
Spring Meadows Subdivision
Job # 000387-3557
20
D Inflow
DOutflow
25 30
Project Manager: Lee Adams
Calculations: Mark Taylor
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.06 1.22
247.24 4.89
247.54 11.00
247.97 12.28
248.51 13.25
249.17 14.43
249.96 15.83
250.86 17.44
251 .89 19.27
253.04 21.31
253.31 21.80
253.52 22.17
253.67 22.44
253.76 22.60
253.79 22.66
253.76 22.60
253.67 22.44
253.52 22.17
253.31 21.80
253.04 21.31
252.71 20.72
252.31 20.02
251 .86 19.22
251 .35 18.30
250.77 17.28
250.14 16.15
249.45 14.92
248.69 13.57
247.88 12.12
247.00 10.56
915102
Drainage Area 1
Sub-Area Area Flowrate
(sq ft) (acres) (cfs)
1 14495.35 0.3328 2.608
2 93652.24 2.1500 11 .232
3 93654.16 2.1500 11 .232
4 12609.7 0.2895 2.268
5 56475.42 1.2965 6.773
6 15021.71 0.3449 2.702
7 15024.72 0.3449 2.703
8 21079.86 0.4839 3.792
9 40143.4 0.9216 4.814
Area 1 Pipe Size
Section Flowrate Velocity Diameter
(cfs) (ft/s) (in)
AB 11 .240 11.18 18
SD 25.290 13.55 24
CD 7.025 11.18 18
DE 32.315 13.55 24
EF 46.365 15.72 30
Out 56.200 15.72 30
Out Adjusted
Velocity Diameter
(ft/s) (in)
7.95 36
Sub-Area
1
2
3
4
5
6
7
8
9
10
Section
AB
BC
CD
DE
Out
Drainage Area 2
Area
(sq ft) (acres)
16352.09 0.3754
8278.26 0.1900
100766.97 2.3133
21907.24 0.5029
15030.93 0.3451
15030.93 0.3451
14822.03 0.3403
15027.27 0.3450
24033.67 0.5517
8650.61 0.1986
Area 2 Pipe Size
Flowrate
(cfs)
7.025
14.050
28.100
35.125
42.150
Velocity
(ft/s)
11 .18
11.1 8
11 .18
13.55
13.55
Out Adjusted
Velocity Diameter
(ft/s) (in)
8.59 30
Flowrate
(cfs)
2.942
0.993
12.085
2.627
2.704
2.704
2.666
2.703
2.882
1.037
Diameter
(in)
18
18
18
24
24
Drainage Area 3
Sub-Area Area Flowrate
(sq ft) (acres) (cfs)
1 84187.82 1.9327 10.097
2 15026.4 0.3450 2.703
3 19294.88 0.4429 3.471
4 45159.16 1.0367 5.416
5 8263.42 0.1897 1.487
6 3768.63 0.0865 0.678
7 14174.35 0.3254 2.550
8 11083.22 0.2544 1.994
9 9457.14 0.2171 1.701
10 14224.14 0.3265 1.706
11 68879.03 1.5812 8.261
12 59013.84 1.3548 7.078
13 95729.33 2.1976 11.481
14 26690.91 0.6127 3.201
Area 3 Pipe Size
Section Flowrate Velocity Diameter
(cfs) (ft/s) (in)
AC 11 .240 11.18 18
BC 11 .240 11 .18 18
CD 22.480 13.55 24
ED 9.835 11 .18 18
DF 42.150 15.72 30
GF 14.050 11 .18 18
FJ 56.200 15.72 30
HI 7.025 11.18 18
IJ 14.050 11 .18 18
Out 70.250 15.72 30
Out Adjusted
Velocity Diameter
(ft/s) (in)
9.94 36
Storm Simulation Synopsis
2-Year 5-Year 10-Year 25-Year 50-Year
Storm Depth (ft) 3.69 4.49 5.04 5.76 6.51
Storm Elevation (ft) 250.69 251.49 252.04 252.76 253.51
Storm Volume (cf) 41027.18 49887.90 55994.63 63951 .53 72292.50
Supplied Capacity (cf) 89466.24 89466.24 89466.24 89466.24 89466.24
Percent of Capacity 46% 56% 63% 71% 81%
Supplied Freeboard (ft) 4.31 3.51 2.96 2.24 1.49
Channel Storage Volume as Percent of Maximum Volume
100%
90%
QI 80% E :I 70% 0 > E 60% :I E ';:( 50% "' ~ -40% 0 c QI 30% tJ ... QI c.. 20%
10%
0%
2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
Design Storm
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
100-Year
6.79
253.79
75479.85
89466.24
84%
1.21
915102
Inlet Sizing Pipe Sizing
Inlet# Length Area Flowrate Section Flowrate Velocity Diameter
(ft) (acres) (cfs) (cfs) (ft/s) (in)
A1 8 0.9447 6.199 A1-A2 6.199 3.51 18
A2 10 2.4828 13.84 A2-A2' 20.039 6.38 24
A3 5 0.8057 5.11 A3-A2' 5.11 2.89 18
A4 10 2.4395 13.5 A2'-A4 25.149 8.01 24
AS 7 1.6414 9.475 A4-A5 38.649 12.3 24
81 5 0.848 5.331 A out 48.124 9.8 30
82 5 1.0954 6.623 82-81 6.623 3.75 18
01 8 1.9327 10.097 81-08 11 .954 6.76 18
02 8 1.9262 10.964 08-07 26.705 8.5 24
03 7 1.4796 8.887 07-09 29.9045 9.52 24
04 7 1.5719 8.779 Oout 33.343 10.61 24
05 5 0.6027 3.871 01-01 I 10.097 5.71 18
06 5 0.9381 5.751 02-01' 10.964 6.2 18
07 5 0.44 3.1995 01'-03 21 .061 6.7 24
08 11 2.6536 14.751 04-03 8.779 4.97 18
09 5 0.4704 3.4385 03-03' 29.84 9.5 24
F1 10 2.452 13.475 F1-03' 13.475 7.63 18
03'-05' 43.315 8.82 30
06-05 5.751 3.25 18
05-05' 9.622 5.44 18
Oout 52.937 10.78 30
,
Weir Diameter
From Bernouli's Equation , the velocity at capacity is:
V= 24.189 ft/s
Flowrate: Q=VA
Q= flowrate in cfs
V= velocity in ft/s
A= area of whole in sq ft
Q= 29.436 cfs
V= 24.189 ft/s
The area of the Weir exit is:
A= 1.217 sq ft
The circular Weir exit diameter is:
Spring Meadows Subdivision
Job# 000387-3557
D= 14.937 in
Project Manager: Lee Adams
Calculations: Mark Taylor
915102
2551 Texas Ave. South, Ste. A, College Station, TX 77840
Ofc: 979.693.5359 Fax: 979.693.4243 Email: mdgcs@mdgcs.com Web : www.mdgcs.com
October 31 , 2002
Mr. Spencer Thompson
1101 Texas Ave
College Station, Texas 77840
RE: Revised Drainage
Spring Meadows Subdivision
Dear Mr. Thompson,
I have attached a revised drainage report for referenced subdivision per your comments dated
October 10, 2002. The changes in the report are reflected in the construction plans.
If yo u have any questions please contact me.
Very sincerely yours,
Municipal Development Group
~ : : I _U
STONE CIWIE er.
EXH IBIT DRAWING 1
PRE-DEVELOPMENT
DRAINAGE AREAS
37.44 ACRES SCALE: 1"=100'
ACREAGE BREAt<pOWN
(]) -11.24 ACRES
CZ> -26.20 ACRES
w :~' ··;;;.--: .• ; .~
"':f! ~
.... I 1 I
L
I
I 1:
\
}
\
/'
v--b-... •
' -
·,
1( \
.... l ~ "!'. ,./
M-1 ZONE /
/
DRAWING 2 EXHIBIT ELOPMENT
POST l~~E AREAS D~ 24 ACRES,
. 1"=100 SCALE:
r--------------------------
1
Pre-Development
GENERAL INFORMATION
Description: Predevelopment Drainage Area 1
Drainage Area (ApRE) = 11 .240 acres
TIME OF CONCENTRATION <Tel
GIVEN
Maximum Travel Distance (DPRE) =
Composite Velocity
Composite Coeffcient of Runoff
**NOTE: Minimum Tc allowed = 10 min.
1660 ft
1.80 ft/sec
0.27
2 YEAR FREQUENCY. RA TE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient (d) = 8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.785
Coefficient (b) = 76
Coefficient (d) = 8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.763
Coefficient (b) =
Coefficient (d) =
80
8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.754
Coefficient (b) = 89
Coefficient (d) = 8.5
50 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745
Coefficient (b) = 98
Coefficient (d) = 8.5
100 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.73
Coefficient (b) =
Coefficient (d) =
96
8
RESULT
Tc(PREJ =
Rainfall Intensity (12) =
02=
Rainfall Intensity (1 5) =
Os=
Rainfall Intensity (1 10) =
010 =
Rainfall Intensity (125) =
Q25=
Rainfall Intensity (150) =
Q50=
Rainfall Intensity (1100) =
0100 =
Spring Meadows Subdivision
Job # 000387 -3557
Project Manager: Lee Adams
Calculations: Mark Taylor
15.37 min.
in/ 5.126 hr
15.686 cfs
6.298 in/hr
19.272 cfs
7.109 in/hr
21.753 cfs
8.137 in/hr
24.901 cfs
in/ 9.220 hr
28.214 cfs
9.619 in/hr --29.436 cfs
10/26/02
Pre-Development
GENERAL INFORMATION
Description: Predevelopment Drainage Area 2
Drainage Area (APRE) = 26.200 acres
TIME OF CONCENTRATION <Tel
GIVEN
Maximum Travel Distance (DPRE) =
Composite Velocity
Composite Coeffcient of Runoff
1780 ft
2.00 ft/sec
0.30
**NOTE: Minimum Tc allowed = 10 min.
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient ( d) = 8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.785
Coefficient (b) = 76
Coefficient (d) = 8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient ( d) =
0.763
80
8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
RESULT
Tc(PREJ =
Rainfall Intensity (12) =
02=
Rainfall Intensity (1 5) =
Os=
Rainfall Intensity (1 10) =
010 =
Coefficient (e) = 0.754 Rainfall Intensity (125) =
Coefficient (b) = 89 Q25 =
Coefficient (d) = 8.5
50 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745 Rainfall Intensity (150) =
14.8 min.
5.229 in/hr --41.442 cfs
in/ 6.419 hr
50.870 cfs
7.241 in/hr
57.388 cfs
8.287 in/hr
65.680 cfs
in/ 9.387 hr --Coefficient (b) = 98 Q50 = 74.400 cfs
Coefficient (d) = 8.5
100 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.73 Rainfall Intensity (1100) = 9.794 in/hr ----Coefficient (b) = 96 Q100 = 77 .626 cfs
Coefficient (d) = 8
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
10/25/02
Post-Development
GENERAL INFORMATION RESULT (Area 1,2 & 5)
Description: Drainage Basin Postdevelopment.
6.327 in/hr Drainage Area (1) = 8.620 acres Rainfall Intensity (12) =
Drainage Area (2) = 2.070 acres Qz= 60.781 cfs
Drainage Area (3) = 12.290 acres
Drainage Area (4) = 5.070 acres
Drainage Area (5) = 5.190 acres
Total 33.240 acres Rainfall Intensity (15) = 7.693 in/hr
Qg= 73.908 cfs
Velocity of Runoff {V1) = 8.50 ft/sec
Coefficient of Runoff (C1) = 0.60
Velocity of Runoff {V2) = 8.70 ft/sec
Coefficient of Runoff (C2) = 0.60 Rainfall Intensity (110) = 8.635 in/hr
Velocity of Runoff (V3) = 8.60 ft/sec Q1o= 82.955 cfs
Coefficient of Runoff (C3) = 0.60
Velocity of Runoff (V4) = 8.60 ft/sec
Coefficient of Runoff (C4)= 0.60
Velocity of Runoff (V5) = 8.00 ft/sec Rainfall Intensity (125) = 9.861 in/hr
Coefficient of Runoff (C5) = 0.60 Qzs= 94.743 cfs
Area 1.2 & 5
Total Area 15.88 acres
Composite Velocity 8.36 ft/sec Rainfall Intensity (150) = 11 .148 in/hr
Composite Coeffcient of Runoff 0.60 Qgo= 107.100 cfs
Composite Time of Concentration 10.00 min
Area 3 &4
Total Area 17.36 acres Rainfall Intensity (1100) = 11 .639 in/hr
Composite Velocity 8.60 ft/sec Q,oo= 111.822 cfs
Composite Coeffcient of Runoff 0.60
Composite Time of Concentration 10.00 min
**NOTE: Minimum Tc allowed = 1 O min. RESULT (Area 3 & 4)
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient (d) = 8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.785
76
8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.763
80
8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.754
89
8.5
50 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.745
98
8.5
100 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.73
96
8
Rainfall Intensity (Ii) =
Qz=
Rainfall Intensity (15) =
Qg=
Rainfall Intensity (110) =
Q,o=
Rainfall Intensity (125) =
Qzs=
Rainfall Intensity (150) =
Qgo=
Rainfall Intensity (1100) =
Q1..=
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
7.693 in/hr
80.796 cfs
8.635 in/hr
90.687 cfs
11 .148 in/hr
117.081 cfs
11.639 in/hr
122.244 cfs
10/25/02
0
10
20
30
VOL=
0
10
20
30
VOL=
Post-DeveloRment {Area 11 2 & 5} Pre-DeveloRment {Area 1 l
2YEAR
0 0
60.781 15.686
30.391 7.843
0 0.000
40586
25 YEAR
0 0
94.743 24.901
47.372 12.451
0 0.000
62858
5YEAR
0 0
73.908 19.272
36.954 9.636
0 0.000
49172
50YEAR
0
107.100
53.550
0
28.214
14.107
0.000 0
70998
10 YEAR
0 0
82.955 21 .753
41.478 10.877
0 0.000
55082
100 YEAR
0
111 .822
55.911
0
29.436
14.718
0.000 0
74147
2-Year Hydrograph 5-Year Hydrograph
i 80 ~--------~
~ 60 Cl) e> 40 ca ~ 20 ~ o~::::::::::::::::::::;::~~
0 10 20
Time (min)
Spring Meadows Subdivision
Job # 000387-3557
30
D Post-Development
D Pre-Development
0 10 20
Time (min )
Project Manager: Lee Adams
Calculations: Mark Taylor
30
D Post-Development
D Pre-Development
10/25/02
10-Year Hydrograph
i 100 ~~~~~~~~~
~ 80 ei 60
ca 40 .c (,) 20 Cl) 0 0 ..Ji'!::::::::::::.._--...-----.--:::::::::::::.0~
0 10 20 30
Time (min)
D Post-Development
D Pre-Development
50-Year Hydrograph
i 150 -,....-----------.
(,)
-; 100 e> 2 50
(,) 5 0 ~:::::::::::::::::=::;:::~~
0 10 20 30
Time (min)
D Post-Development
D Pre-Development
25-Year Hydrograph
i 100 -,....---------~
~ 80 ei 60
ca 40 .c (,) 20 Cl) 0 0 _Ji'!::::::::..__-...--__ ~....:::=::::::..~
0 10 20 30
Time (min)
D Post-Development
D Pre-Development
100-Year Hydrograph
i 150 ~~~~~~~~~
(,)
-; 100 e> 2 50
(,) 5 0 ~:::::::::::::::::::::::::::~~
0 10 20 30
Time (min)
D Post-Development
D Pre-Development
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
10/25/02
Pre-Development Area 1
Outflow Hydrograph Ordinates
(Cubic Feet per Second)
Time 2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
(min) Storm Storm
0 0 0
1 1.57 1.93
2 3.14 3.85
3 4.71 5.78
4 6.27 7.71
5 7.84 9.64
6 9.41 11 .56
7 10.98 13.49
8 12.55 15.42
9 14.12 17.34
10 15.69 19.27
11 14.90 18.31
12 14.12 17.34
13 13.33 16.38
14 12.55 15.42
15 11.76 14.45
16 10.98 13.49
17 10.20 12.53
18 9.41 11.56
19 8.63 10.60
20 7.84 9.64
21 7.06 8.67
22 6.27 7.71
23 5.49 6.75
24 4.71 5.78
25 3.92 4.82
26 3.14 3.85
27 2.35 2.89
28 1.57 1.93
29 0.78 0.96
30 0 0
Spring Meadows Subdivision
Job # 000387-3557
Storm Storm Storm
0 0 0
2.18 2.49 2.82
4.35 4.98 5.64
6.53 7.47 8.46
8.70 9.96 11 .29
10.88 12.45 14.11
13.05 14.94 16.93
15.23 17.43 19.75
17.40 19.92 22.57
19.58 22.41 25.39
21.75 24.90 28.21
20.67 23.66 26.80
19.58 22.41 25.39
18.49 21 .17 23.98
17.40 19.92 22.57
16.31 18.68 21 .16
15.23 17.43 19.75
14.14 16.19 18.34
13.05 14.94 16.93
11 .96 13.70 15.52
10.88 12.45 14.11
9.79 11.21 12.70
8.70 9.96 11.29
7.61 8.72 9.87
6.53 7.47 8.46
5.44 6.23 7.05
4.35 4.98 5.64
3.26 3.74 4.23
2.18 2.49 2.82
1.09 1.25 1.41
0 0 0
Project Manager: Lee Adams
Calculations: Mark Taylor
Storm
0
2.94
5.89
8.83
11 .77
14.72
17.66
20.61
23.55
26.49
29.44
27.96
26.49
25.02
23.55
22.08
20.61
19.13
17.66
16.19
14.72
13.25
11 .77
10.30
8.83
7.36
5.89
4.42
2.94
1.47
0
10/25/02
Post-Development Area 1,2 &5
Inflow Hydrograph Ordinates
(Cubic Feet per Second)
Time 2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
(min) Storm Storm
0 0 0
1 6.08 7.39
2 12.16 14.78
3 18.23 22.17
4 24.31 29.56
5 30.39 36.95
6 36.47 44.34
7 42.55 51 .74
8 48.62 59.13
9 54.70 66.52
10 60.78 73.91
11 57.74 70.21
12 54.70 66.52
13 51 .66 62.82
14 48.62 59.13
15 45.59 55.43
16 42.55 51 .74
17 39.51 48.04
18 36.47 44.34
19 33.43 40.65
20 30.39 36.95
21 27.35 33.26
22 24.31 29.56
23 21.27 25.87
24 18.23 22.17
25 15.20 18.48
26 12.16 14.78
27 9.12 11 .09
28 6.08 7.39
29 3.04 3.70
30 0 0
Spring Meadows Subdivision
Job # 000387-3557
Storm Storm Storm
0 0 0
8.30 9.47 10.71
16.59 18.95 21.42
24.89 28.42 32.13
33.18 37.90 42.84
41 .48 47.37 53.55
49.77 56.85 64.26
58.07 66.32 74.97
66.36 75.79 85.68
74.66 85.27 96.39
82.96 94.74 107.10
78.81 90.01 101 .75
74.66 85.27 96.39
70.51 80.53 91.04
66.36 75.79 85.68
62.22 71 .06 80.33
58.07 66.32 74.97
53.92 61 .58 69.62
49.77 56.85 64.26
45.63 52.11 58.91
41 .48 47.37 53 .55
37.33 42.63 48.20
33.18 37.90 42.84
29.03 33.16 37.49
24.89 28.42 32.13
20.74 23.69 26.78
16.59 18.95 21 .42
12.44 14.21 16.07
8.30 9.47 10.71
4.15 4.74 5.35
0 0 0
Project Manager: Lee Adams
Calculations: Mark Taylor
Storm
0
11.18
22.36
33.55
44.73
55.91
67.09
78.28
89.46
100.64
111.82
106.23
100.64
95.05
89.46
83.87
78.28
72.68
67.09
61 .50
55.91
50.32
44.73
39.14
33.55
27.96
22.36
16.77
11.18
5.59
0
10/25/02
Channel
Depth vs. Volume
Elevation Depth Volume
(ft) (ft) (cf)
247.0 0.0 0.00
247.5 0.5 5579.32
248.0 1.0 11158.65
248.5 1.5 16737.97
249.0 2.0 22317.29
249.5 2.5 27896.61
250.0 3.0 33475.94
250.5 3.5 39055.26
251.0 4.0 44634.58
251 .5 4.5 50213.90
252.0 5.0 55793.23
252.5 5.5 61372.55
253.0 6.0 66951 .87
253.5 6.5 72531 .19
254.0 7.0 78110.52
254.5 7.5 83689.84
255.0 8.0 89269.16
Channel Depth vs. Volume
9.0
8.0
7.0 = 6.0 -.J: 5.0
0.. 4.0
Q) 3.0 c
2.0
1.0
0.0
0 20000
Spring Meadows Su!;>Siiyj~Jon
Job # 000387 -35~7
40000 60000 80000 100000
Vol ume (cf)
Project Manager: Lee Adams
Calculations: Mark Taylor
10/25/02
Outlet Control
Elevation
(ft)
247.0
247.5
248.0
248.5
249.0
249.5
250.0
250.5
251 .0
251 .5
252.0
252.5
253.0
253.5
254.0
254.5
255.0
0.6
-0.5 !:. 0.4 = 0.3 g. 0.2
c 0.1
0.0
Depth
(ft)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
-----0.0 2.0
10.0
g 8.0
.s::. 6.0 -c. 4.0 CD c 2.0
0.0
0.0 5.0
Velocity Discharge Inlet Velocity =
(ft/s) (cfs) Diameter=
0.00 0.00 Area=
10.10 12.30
11 .59 14.11
12.90 15.71
14.10 17.16
15.20 18.50
16.22 19.75
17.18 20.92
18.10 22.03
18.97 23.09
19.80 24.10
20.59 25.07
21 .36 26.00
22.10 26.91
22.82 27.78
23.51 28.63
24.19 29.45
Depth vs. Discharge
v = 0.0.i 06x __,,,,,,,,,-
-i..--""" --....---
~ -
4.0 6.0 8.0 10.0 12.0 14.0
Discharge (cfs)
Depth vs. Discharge
~ = 0.46 2x -5.9 )87
~
~ ... __,, ~
... ~
10.0 15.0 20.0 25.0 30.0 35.0
Discharge (cfs)
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
8.36 ft/s
1.25 ft
1.22 sq ft
10/25/02
Depth
(ft)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
35.0
:!' 30.0
~ 25.0
& 20.0 ... cu 15.0 .s::.
" 10.0 .!? c 5.0
0.0
Storage Indication
Storage Discharge 2s/t 2s/t+O
(cf) (cfs) (cfs) (cfs)
0.00 0.00 0.00 0.00
5579.32 12.30 185.98 198.28
11158.65 14.11 371 .96 386.06
16737.97 15.71 557.93 573.64
22317.29 17.16 743.91 761.07
27896.61 18.50 929.89 948.39
33475.94 19.75 1115.86 1135.61
39055.26 20.92 1301 .84 1322.76
44634.58 22.03 1487.82 1509.85
50213.90 23.09 1673.80 1696.88
55793.23 24.10 1859.77 1883.87
61372.55 25.07 2045.75 2070.82
66951 .87 26.00 2231 .73 2257.73
72531 .19 26.91 2417.71 2444.61
78110.52 27.78 2603.68 2631.46
83689.84 28.63 2789.66 2818.29
89269.16 29.45 2975.64 3005.09
Discharge vs. 2s/t+O
~ ...............
--------
~
I ,
0.0 500.0 1000.0 1500.0 2000.0 2500.0 3000.0 3500.0
2s/t+O ( cfs)
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
10/25/02
Inflow I Outflow Simulation
2-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 6.08 364.69 11 .35 12.96 0.81
2 12.16 1458.74 45.39 51 .86 3.23
3 18.23 3282.17 102.13 116.68 7.28
4 24.31 5834.98 181 .56 207.43 12.93
5 30.39 9117.15 289.27 318.54 14.63
6 36.47 13128.70 422.21 453.04 15.42
7 42.55 17869.61 579.31 612.00 16.34
8 48.62 23339.90 760.59 795.41 17.41
9 54.70 29539.57 966.03 1003.27 18.62
10 60.78 36468.60 1195.65 1235.59 19.97
11 57.74 38109.69 1250.03 1290.61 20.29
12 54.70 39386.09 1292.33 1333.41 20.54
13 51 .66 40297.80 1322.54 1363.98 20.72
14 48.62 40844.83 1340.67 1382.32 20.83
15 45.59 41027.18 1346.71 1388.43 20.86
16 42.55 40844.83 1340.67 1382.32 20.83
17 39.51 40297.80 1322.54 1363.98 20.72
18 36.47 39386.09 1292.33 1333.41 20.54
19 33.43 38109.69 1250.03 1290.61 20.29
20 30.39 36468.60 1195.65 1235.59 19.97
21 27.35 34462.83 1129.18 1168.34 19.58
22 24.31 32092.37 1050.63 1088.86 19.12
23 21 .27 29357.22 959.99 997.16 18.58
24 18.23 26257.39 857.27 893.23 17.98
25 15.20 22792.88 742.46 777.07 17.30
26 12.16 18963.67 615.57 648.68 16.56
27 9.12 14769.78 476.59 508.06 15.74
28 6.08 10211.21 325.53 355.22 14.85
29 3.04 5287.95 162.38 190.15 13.89
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
2-Year Storm Event
80.00
i' ~ 60.00
Dlnflow .; 40.00 .. DOutflow ~ 20.00 ii:
0.00
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth
(ft)
0.00
0.03
0.13
0.30
0.53
0.82
1.18
1.61
2.10
2.66
3.28
3.43
3.54
3.63
3.68
3.69
3.68
3.63
3.54
3.43
3.28
3.10
2.89
2.64
2.36
2.05
1.71
1.33
0.92
0.48
0.00
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.03 0.66
247.13 2.66
247.30 5.98
247.53 10.63
247.82 12.02
248.18 12.66
248.61 13.42
249.10 14.30
249.66 15.29
250.28 16.41
250.43 16.67
250.54 16.87
250.63 17.02
250.68 17.11
250.69 17.14
250.68 17.11
250.63 17.02
250.54 16.87
250.43 16.67
250.28 16.41
250.10 16.08
249.89 15.70
249.64 15.27
249.36 14.77
249.05 14.21
248.71 13.60
248.33 12.93
247.92 12.20
247.48 11.41
247.00 10.56
10/25/02
Inflow I Outflow Simulation
5-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 7.39 443.45 13.80 15.76 0.98
2 14.78 1773.79 55.19 63.06 3.93
3 22.17 3991 .03 124.19 141 .88 8.85
4 29.56 7095.17 222.27 250.75 14.24
5 36.95 11086.20 354.52 384.56 15.02
6 44.34 15964.13 516.17 548.11 15.97
7 51 .74 21728.95 707.20 741 .39 17.10
8 59.13 28380.67 927.63 964.42 18.39
9 66.52 35919.29 1177.45 1217.17 19.86
10 73.91 44344.80 1456.65 1499.67 21.51
11 70.21 46340.32 1522.78 1566.58 21.90
12 66.52 47892.38 1574.21 1618.61 22.20
13 62.82 49001 .00 1610.95 1655.78 22.42
14 59.13 49666.18 1632.99 1678.09 22.55
15 55.43 49887.90 1640.34 1685.52 22.59
16 51 .74 49666.18 1632.99 1678.09 22.55
17 48.04 49001 .00 1610.95 1655.78 22.42
18 44.34 47892.38 1574.21 1618.61 22.20
19 40.65 46340.32 1522.78 1566.58 21 .90
20 36.95 44344.80 1456.65 1499.67 21 .51
21 33.26 41905.84 1375.83 1417.89 21 .03
22 29.56 39023.42 1280.31 1321 .25 20.47
23 25.87 35697.56 1170.10 1209.74 19.82
24 22.17 31928.26 1045.19 1083.36 19.09
25 18.48 27715.50 905.59 942.11 18.26
26 14.78 23059.30 751 .29 786.00 17.35
27 11.09 17959.64 582.30 615.01 16.36
28 7.39 12416.54 398.61 429.16 15.28
29 3.70 6430.00 200.22 228.44 14.11
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
5-Year Storm Event
80.00
~ 60.00
~ 40.00 D Inflow .. DOutflow ~ 20.00 ii: 0.00
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job # 000387 -3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth
(ft)
0.00
0.04
0.16
0.36
0.64
1.00
1.44
1.96
2.55
3.23
3.99
4.17
4.31
4.41
4.47
4.49
4.47
4.41
4.31
4.17
3.99
3.77
3.51
3.21
2.87
2.49
2.08
1.62
1.12
0.58
0.00
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.04 0.81
247.16 3.23
247.36 7.27
247.64 11 .70
248.00 12.34
248.44 13.12
248.96 14.04
249.55 15.11
250.23 16.32
250.99 17.67
251 .17 17.99
251 .31 18.24
251.41 18.41
251.47 18.52
251.49 18.56
251.47 18.52
251.41 18.41
251 .31 18.24
251 .17 17.99
250.99 17.67
250.77 17.28
250.51 16.81
250.21 16.28
249.87 15.68
249.49 15.00
249.08 14.26
248.62 13.44
248.12 12.55
247.58 11 .59
247.00 10.56
10/25/02
Inflow I Outflow Simulation
10-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 8.30 497.73 15.49 17.69 1.10
2 16.59 1990.92 61 .95 70.78 4.41
3 24.89 4479.57 139.39 159.25 9.93
4 33.18 7963.68 251.05 279.87 14.41
5 41.48 12443.25 399.49 430.06 15.28
6 49.77 17918.28 580.92 613.63 16.35
7 58.07 24388.77 795.34 830.57 17.61
8 66.36 31854.72 1042.75 1080.90 19.07
9 74.66 40316.13 1323.15 1364.59 20.72
10 82.96 49773.00 1636.53 1681 .67 22.57
11 78.81 52012.79 1710.75 1756.76 23.00
12 74.66 53754.84 1768.48 1815.17 23.34
13 70.51 54999.17 1809.72 1856.89 23.59
14 66.36 55745.76 1834.46 1881 .93 23.73
15 62.22 55994.63 1842.71 1890.27 23.78
16 58.07 55745.76 1834.46 1881 .93 23.73
17 53.92 54999.17 1809.72 1856.89 23.59
18 49.77 53754.84 1768.48 1815.17 23.34
19 45.63 52012.79 1710.75 1756.76 23.00
20 41 .48 49773.00 1636.53 1681 .67 22.57
21 37.33 47035.49 1545.82 1589.88 22.03
22 33.18 43800.24 1438.61 1481.41 21.40
23 29.03 40067.27 1314.90 1356.25 20.67
24 24.89 35836.56 1174.70 1214.40 19.85
25 20.74 31108.12 1018.01 1055.86 18.93
26 16.59 25881.96 844.83 880.64 17.91
27 12.44 20158.06 655.15 688.72 16.79
28 8.30 13936.44 448.97 480.12 15.57
29 4.15 7217.08 226.31 254.83 14.26
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
10-Year Storm Event
100.00
i' 80.00 ~ 60.00 D Inflow .s !!! 40.00 DOutflow ~ 0 20.00 ii:
0.00
0 5 10 15 20 25 30
Time(min)
Spring Meadows Subdivision
Job # 000387 -3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth
(ft)
0.00
0.04
0.18
0.40
0.72
1.12
1.61
2.19
2.87
3.63
4.48
4.68
4.84
4.95
5.02
5.04
5.02
4.95
4.84
4.68
4.48
4.23
3.94
3.61
3.23
2.80
2.33
1.81
1.25
0.65
0.00
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.04 0.91
247.18 3.63
247.40 8.16
247.72 11 .84
248.12 12.55
248.61 13.43
249.19 14.47
249.87 15.67
250.63 17.02
251.48 18.54
251.68 18.90
251 .84 19.18
251 .95 19.38
252.02 19.50
252.04 19.54
252.02 19.50
251.95 19.38
251.84 19.18
251 .68 18.90
251.48 18.54
251 .23 18.10
250.94 17.58
250.61 16.98
250.23 16.30
249.80 15.55
249.33 14.71
248.81 13.79
248.25 12.79
247.65 11 .72
247.00 10.56
10/25/02
Inflow I Outflow Simulation
25-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 9.47 568.46 17.69 20.21 1.26
2 18.95 2273.83 70.75 80.84 5.04
3 28.42 5116.12 159.20 181 .88 11.34
4 37.90 9095.33 288.55 317.81 14.63
5 47.37 14211.45 458.09 489.34 15.63
6 56.85 20464.49 665.30 699.00 16.85
7 66.32 27854.44 910.19 946.77 18.29
8 75.79 36381 .31 1192.76 1232.66 19.95
9 85.27 46045.10 1513.00 1556.68 21 .84
10 94.74 56845.80 1870.91 1918.81 23.95
11 90.01 59403.86 1955.68 2004.58 24.45
12 85.27 61393.46 2021 .61 2071.28 24.84
13 80.53 62814.61 2068.71 2118.93 25.11
14 75.79 63667.30 2096.96 2147.52 25.28
15 71 .06 63951.53 2106.38 2157.05 25.33
16 66.32 63667.30 2096.96 2147.52 25.28
17 61 .58 62814.61 2068.71 2118.93 25.11
18 56.85 61393.46 2021.61 2071 .28 24.84
19 52.11 59403.86 1955.68 2004.58 24.45
20 47.37 56845.80 1870.91 1918.81 23.95
21 42.63 53719.28 1767.30 1813.98 23.34
22 37.90 50024.30 1644.86 1690.09 22.62
23 33.16 45760.87 1503.58 1547.15 21 .78
24 28.42 40928.98 1343.46 1385.14 20.84
25 23.69 35528.63 1164.50 1204.08 19.79
26 18.95 29559.82 966.70 1003.95 18.62
27 14.21 23022.55 750.07 784.77 17.35
28 9.47 15916.82 514.60 546.52 15.96
29 4.74 8242.64 260.29 289.22 14.46
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
25-Year Storm Event
100.00
~ 80.00 ~ 60.00 Dlnflow .s f 40.00 DOutflow ~ 0 20.00 u:::
0.00
0 5 10 15 20 25 30
Time{min)
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth
(ft)
0.00
0.05
0.20
0.46
0.82
1.28
1.84
2.51
3.27
4.14
5.12
5.35
5.53
5.65
5.73
5.76
5.73
5.65
5.53
5.35
5.12
4.83
4.50
4.12
3.68
3.20
2.66
2.07
1.43
0.74
0.00
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.05 1.04
247.20 4.14
247.46 9.32
247.82 12.02
248.28 12.84
248.84 13.84
249.51 15.02
250.27 16.39
251 .14 17.94
252.12 19.67
252.35 20.08
252.53 20.40
252.65 20.63
252.73 20.77
252.76 20.81
252.73 20.77
252.65 20.63
252.53 20.40
252.35 20.08
252.12 19.67
251.83 19.17
251 .50 18.58
251.12 17.89
250.68 17.12
250.20 16.25
249.66 15.30
249.07 14.25
248.43 13.11
247.74 11.88
247.00 10.56
10/25/02
... ,;
•' ~
....... -··· ,,t' ', .,
"' . '
Inflow I Outflow Simulation
50-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 10.71 642.60 20.00 22.84 1.42
2 21.42 2570.40 79.98 91 .38 5.70
3 32.13 5783.40 179.96 205.60 12.82
4 42.84 10281.60 327.86 357.58 14.86
5 53.55 16065.00 519.51 551.49 15.99
6 64.26 23133.60 753.75 788.49 17.37
7 74.97 31487.40 1030.58 1068.58 19.00
8 85.68 41126.40 1350.00 1391 .76 20.88
9 96.39 52050.60 1712.01 1758.03 23.01
10 107.10 64260.00 2116.61 2167.39 25.39
11 101 .75 67151 .70 2212.43 2264.35 25.96
12 96.39 69400.80 2286.96 2339.76 26.40
13 91 .04 71007.30 2340.20 2393.62 26.71
14 85.68 71971.20 2372.14 2425.94 26.90
15 80.33 72292.50 2382.79 2436.71 26.96
16 74.97 71971 .20 2372.14 2425.94 26.90
17 69.62 71007.30 2340.20 2393.62 26.71
18 64.26 69400.80 2286.96 2339.76 26.40
19 58.91 67151 .70 2212.43 2264.35 25.96
20 53.55 64260.00 2116.61 2167.39 25.39
21 48.20 60725.70 1999.48 2048.90 24.71
22 42.84 56548.80 1861.07 1908.85 23.89
23 37.49 51729.30 1701 .36 1747.26 22.95
24 32.13 46267.20 1520.36 1564.12 21 .88
25 26.78 40162.50 1318.06 1359.44 20.69
26 21.42 33415.20 1094.46 1133.22 19.38
27 16.07 26025.30 849.58 885.44 17.93
28 10.71 17992.80 583.39 616.13 16.37
29 5.35 9317.70 295.92 325.26 14.67
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
50-Year Storm Event
150.00
~ ~ 100.00 Olnflow ...s E 50.00 OOutflow 3: 0 ii: 0.00
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth
(ft)
0.00
0.06
0.23
0.52
0.93
1.45
2.08
2.83
3.70
4.68
5.78
6.04
6.25
6.39
6.48
6.51
6.48
6.39
6.25
6.04
5.78
5.47
5.09
4.66
4.16
3.61
3.01
2.34
1.62
0.84
0.00
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.06 1.17
247.23 4.68
247.52 10.53
247.93 12.21
248.45 13.13
249.08 14.27
249.83 15.61
250.70 17.15
251 .68 18.90
252.78 20.86
253.04 21 .32
253.25 21 .68
253.39 21 .94
253.48 22.10
253.51 22.15
253.48 22.10
253.39 21 .94
253.25 21 .68
253.04 21.32
252.78 20.86
252.47 20.29
252.09 19.62
251 .66 18.85
251 .16 17.98
250.61 17.00
250.01 15.92
249.34 14.73
248.62 13.44
247.84 12.05
247.00 10.56
10/25/02
__ . _ _..._ ·--~·;•, .. ,,:~ ... r;
'. -! ; -~ ..
Inflow I Outflow Simulation
100-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 11 .18 670.93 20.88 23.85 1.49
2 22.36 2683.73 83.51 95.41 5.95
3 33.55 6038.39 187.89 214.67 13.39
4 44.73 10734.91 342.88 372.78 14.95
5 55.91 16773.30 542.98 575.24 16.13
6 67.09 24153.55 787.55 822.69 17.57
7 78.28 32875.67 1076.59 1115.13 19.27
8 89.46 42939.65 1410.09 1452.56 21.23
9 100.64 54345.49 1788.06 1834.98 23.46
10 111 .82 67093.20 2210.49 2262.39 25.95
11 106.23 70112.39 2310.54 2363.62 26.54
12 100.64 72460.66 2388.36 2442.35 27.00
13 95.05 74137.99 2443.94 2498.59 27.32
14 89.46 75144.38 2477.29 2532.33 27.52
15 83.87 75479.85 2488.41 2543.58 27.58
16 78.28 75144.38 2477.29 2532.33 27.52
17 72.68 74137.99 2443.94 2498.59 27.32
18 67.09 72460.66 2388.36 2442.35 27.00
19 61.50 70112.39 2310.54 2363.62 26.54
20 55.91 67093.20 2210.49 2262.39 25.95
21 50.32 63403.07 2088.21 2138.66 25.23
22 44.73 59042.02 1943.69 1992.44 24.38
23 39.14 54010.03 1776.94 1823.73 23.39
24 33.55 48307.10 1587.96 1632.52 22.28
25 27.96 41933.25 1376.74 1418.81 21 .04
26 22.36 34888.46 1143.29 1182.61 19.66
27 16.77 27172.75 887.60 923.92 18.16
28 11 .18 18786.10 609.68 642.72 16.52
29 5.59 9728.51 309.53 339.04 14.75
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
100-Year Storm Event
150.00
:!' ~ 100.00 Dlnflow .! Ill .. 50.00 DOutflow it 0 ~
0.00
0 5 10 15 20 25 30
Time(min)
Spring Meadows Subdivision
Job # 000387 -3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth
(ft)
0.00
0.06
0.24
0.54
0.97
1.51
2.17
2.96
3.86
4.89
6.04
6.31
6.52
6.67
6.76
6.79
6.76
6.67
6.52
6.31
6.04
5.71
5.31
4.86
4.35
3.77
3.14
2.45
1.69
0.88
0.00
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.06 1.22
247.24 4.89
247.54 11 .00
247.97 12.28
248.51 13.25
249.17 14.43
249.96 15.83
250.86 17.44
251 .89 19.27
253.04 21 .31
253.31 21 .80
253.52 22.17
253.67 22.44
253.76 22.60
253.79 22.66
253.76 22.60
253.67 22.44
253.52 22.17
253.31 21 .80
253.04 21.31
252.71 20.72
252.31 20.02
251 .86 19.22
251 .35 18.30
250.77 17.28
250.14 16.15
249.45 14.92
248.69 13.57
247.88 12.12
247.00 10.56
10/25/02
Storm Simulation Synopsis
2-Year 5-Year 10-Year 25-Year 50-Year
Storm Depth (ft) 3.69 4.49 5.04 5.76 6.51
Storm Elevation (ft) 250.69 251.49 252.04 252.76 253.51
Storm Volume (cf) 41027.18 49887.90 55994.63 63951 .53 72292.50
Supplied Capacity (cf) 89466.24 89466.24 89466.24 89466.24 89466.24
Percent of Capacity 46% 56% 63% 71% 81%
Supplied Freeboard (ft) 4.31 3.51 2.96 2.24 1.49
Channel Storage Volume as Percent of Maximum Volume
100%
90%
Cl) E 80%
:I 0 70% >
E 60% :I E ·;c 50% ns
:::E .... 40% 0 -c 30% Cl) -~ Cl) 20% Q.
10%
0%
2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
Design Storm
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
100-Year
6.79
253.79
75479.85
89466.24
84%
1.21
10/25/02
t" t' Ip lttj
/ 1. /'
I# ;, ---SCILL,:J-• llld'
,,....,,--------..-.....--.J. _ .... -
. -·· -~ . __ .. .,......... . "' ... --......... . ... ~ ..... ~_.._...,,____,,,,.,.,,....-~--·~--,----
Inlet Sizing
10-Year Storm Event
Inlet# Length Area Flowrate
(ft) (acres) (cfs)
A1 8 0.9447 6.199
A2 10 2.4828 13.840
A3 5 0.8057 5.110
A4 10 2.4395 13.500
AS 7 1.6414 9.475
81 5 0.848 5.331
82 5 1.0954 6.623
01 8 1.9262 10.964
02 8 1.9327 10.097
03 7 1.4796 8.887
04 7 1.5719 8.779
05 5 0.9381 5.751
06 5 0.6027 3.871
07 11 2.6536 14.751
08 5 0.44 3.200
09 5 0.4704 3.439
F1 10 2.452 13.475
Pipe Sizing
10-Year Storm Event
Section Flowrate Velocity Diameter Length Friction Loss Junction Loss
(cfs) (fUs)
A1-A1' 6.199 3.51
A2-A1' 13.840 7.83
A1'-A3 20.039 6.38
A3-A3' 25.149 8.01
A4-A3' 13.500 7.64
A3'-A5 38.649 7.87
Aout 48.124 9.80
81-82 6.623 3.75
82-06' 11 .954 6.76
05-06 5.751 3.25
06-06' 9.622 5.44
06'-08 21 .576 6.87
07-08 14.751 8.35
08-09 36.327 7.40
Oout 39.766 8.10
01-02 10.964 6.20
02-03 21 .061 6.70
04-03 8.779 4.97
03-03' 38.727 7.89
F1-03' 13.475 7.63
Oout 52 .202 10.63
Spring Meadows Subdivision
Job # 000387-3557
(in)
18
18
24
24
18
30
30
18
18
18
18
24
18
30
30
18
24
18
30
18
30
(ft) (ft)
360 1.067
75 1.106
397.5 2.654
315 3.315
60 0.842
240 1.812
217.5 2.547
97.5 0.33
375 4.121
90 0.229
285 2.028
315 0.581
75 1.258
232.5 1.552
217.5 1.74
75 0.693
405 2.982
75 0.446
240 1.821
157.5 2.205
735 10.125
Project Manager: Lee Adams
Calculations: Mark Taylor
(ft)
0.333
-0 .241
0.458
-0 .026
0.042
0.666
0.618
0.018
0.372
0.206
0.148
-0.292
0.212
0.126
0.339
0.733
0.595
0.642
10/25/02
.... :~
'·
"
10-Year Hydraulic Gradient Lines
g 265 -A
c: -s 0 ;:
I""" 01 "' > G> -02 w 260
245 +-~~~~~~~~~~~~~~~~~~~~-.-~~~~~~~~~~~~-.-~~~---1
0 200 400 600 800 1000 1200 1400 1600 1800
Distance (ft)
Inlet Sizing
100-Year Storm Event
Inlet# Length Area Flowrate
(ft) (acres) (cfs)
A1 8 0.9447 9.978
A2 10 2.4828 17.483
A3 5 0.8057 8.510
A4 10 2.4395 17.178
AS 7 1.6414 11.558
81 5 0.848 8.957
82 5 1.0954 7.713
01 8 1.9262 13.564
02 8 1.9327 13.609
03 7 1.4796 10.419
04 7 1.5719 11 .069
05 5 0.9381 6.606
06 5 0.6027 6.366
07 11 2.6536 18.686
08 5 0.44 4.648
09 5 0.4704 4.969
F1 10 2.452 17.266
Pi pe Sizing
100-Year Storm Event
Section Flowrate Velocity Diameter Length Friction Loss Junction Loss
(cfs) (ft/s)
A1 -A1' 9.978 5.65
A2-A1 ' 17.483 9.89
A1 '-A3 27.461 8.74
A3-A3' 35.971 11 .45
A4-A3' 17.178 9.72
A3'-A5 53.149 10.83
Aout 64.707 13.18
81-82 8.957 5.07
82-06' 16.670 9.43
05-06 6.606 3.74
06-06' 12.972 7.34
06'-08 29.642 9.44
07-08 18.686 10.57
08-09 48.328 9.85
Oout 53.297 10.86
01 -02 13.564 7.68
02-03 27.173 8.65
04-03 11 .069 6.26
03-03' 48.661 9.91
F1-03' 17.266 9.77
Oout 65.927 13.43
Spring Meadows Subdivision
Job # 000387 -3557
(in)
18
18
24
24
18
30
30
18
18
18
18
24
18
30
30
18
24
18
30
18
30
(ft) (ft)
360 2.764
75 1.764
397.5 4.981
315 6.774
60 1.363
240 3.432
217.5 4.606
97.5 0.603
375 8.02
90 0.303
285 3.693
315 4.605
75 2.015
232.5 2.75
217.5 3.127
75 1.064
405 4.971
75 0.707
240 2.874
157.5 3.616
735 16.162
Project Manager: Lee Adams
Calculations: Mark Taylor
(ft)
0.521
-0.251
1.069
-0.162
0.267
1.102
1.235
0.002
0.779
0.413
0.154
-0.287
0.409
0.309
0.457
1.153
0.963
0.995
10/25/02
100-Year Hydraulic Grade Lines
225 -t--~~~-.--~~~-,-~~~~,--~~~-.-~~~-.-~~~~.--~~~-.--~~~--.-~~~---i
0 200 400 600 800 1000 1200 1400 1600 1800
Length (ft)
-A
-s
c: 01
-02
Weir Diameter
From Bernouli's Equation, the velocity at capacity is:
V= 24.189 ft/s
Flowrate: Q=VA
Q= flowrate in cfs
V= velocity in ft/s
A= area of whole in sq ft
Q= 29.436 cfs
V= 24.189 ft/s
The area of the Weir exit is:
A= 1.217 sq ft
The circular Weir exit diameter is:
D= 14.937 in
i• ..... ,
: ' .· ...... . Spring Meadows Subdivision Project Manager: Lee Adams
Calculations: Mark Taylor Job # 000387-3557
10/25/02
' .
'&..~ _:,.~.,~ .. ~"'..v0o\:J" -<:)~~~
2551 Texas Ave. South, Ste. A, CoUege Station, TX 77840
Ofc: 979.693.5359 Fax: 979.693.4243 Email: mdgcs@mdgcs.com Web: www.mdgcs.com
December 6, 2002
Mr. Spencer Thompson
11 01 Texas Ave
College Station, Texas 77840
RE: Revised Drainage Report
Spring Meadows Subdivision
Dear Mr. Thompson,
I have attached a revised drainage report for referenced subdivision per your comments dated
November 18, 2002. We revised some pipe sizes to accommodate the hydraulic gradient for the
10 year and for the most part contains the 100 year storm. The changes in the report are reflected
in the construction plans.
If you have any questions please contact me .
Very sincerely yours,
Municipal Development Group
Lenwood S. Adams, P.E .
Senior Project Manager
Executive Vice President
Y-1 ZllNE / /'
&IDIJIIml"-1#'
EXHIBIT DRAWING 1
PRE-DEVELOPMENT
DRAINAGE AREAS
37.44 ACRES SCALE: 1"=100'
ACRfAGE BREAKDOWN
(l) -11.24 ACRES
0 -26.20 ACRES
.,_ -W•• . •w _ ...
--". ~:i
,_,
+"•Cl
u~: :tOllO: \
v-ci:m~ ,.1 /
··l J
t.:' -,-.... "" /
M-1 ZONE /
EXHIBITDEVDRAEL~~~GEN~ POST-S DRAINAGE AREA
33.24 ~CRES •
SCALE: 1 =100
r·
• I I
l
I
I .
--~
~[ /
:[/
Pre-Development
GENERAL INFORMATION
Description: Predevelopment Drainage Area 1
Drainage Area (APRE) = 11 .240 acres
TIME OF CONCENTRATION (Tc)
GIVEN
Maximum Travel Distance (DPRE) =
Composite Velocity
Composite Coeffcient of Runoff
1660 ft
1.80 ft/sec
0.27
**NOTE: Minimum T c allowed = 10 min .
2 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient (d) = 8
5 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.785
76
8.5
10 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient (d) =
0.763
80
8.5
25 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient (d) =
0.754
89
8.5
50 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745
Coefficient (b) = 98
Coefficient (d) = 8.5
100 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.73
96
8
RESULT
Tc(PRE) =
Rainfall Intensity (1 2) =
02=
Rainfall Intensity (1 5) =
Os=
15.37 min.
in/ 5.126 hr
15.686 cfs
Rainfall Intensity (1 10) = 7.109 in/hr
0 10 = 21.753 cfs
~~--------~~~~-
Rainfall Intensity (1 25) =
02s =
Rainfall Intensity (150) =
Oso =
Rainfall Intensity (1 100) =
0100 =
in/ 9.220 hr
28.214 cfs
9.619 in/hr
29.436 cfs
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
11/19/2002
Pre-Development
GENERAL INFORMATION
Description: Predevelopment Drainage Area 2
Drainage Area (APRE) = 26.200 acres
TIME OF CONCENTRATION <T c)
GIVEN
Maximum Travel Distance (DPRE) =
Composite Velocity
Composite Coeffcient of Runoff
1780 ft
ft 2.00 fsec
0.30
**NOTE: Minimum Tc allowed = 10 min.
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient {d) = 8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient (d) =
0.785
76
8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient (d) =
0.763
80
8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.754
Coefficient (b) =
Coefficient (d) =
89
8.5
50 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.745
98
8.5
100 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient (d) =
0.73
96
8
RESULT
Tc(PRE) =
Rainfall Intensity (12) =
02=
Rainfall Intensity (15) =
Os=
Rainfall Intensity (110) =
0 10 =
Rainfall Intensity (125) =
025 =
Rainfall Intensity (15o) =
Oso =
Rainfall Intensity (1100) =
0100 =
Spring Meadows Subdivision
Job # 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
14.8 min.
in/ 5.229 hr
41.442 cfs
in/ 6.419 hr
50.870 cfs
in/ 7.241 hr
57.388 cfs
8.287 in/hr
65.680 cfs
9.387 in/hr
74.400 cfs
in/ 9.794 hr
77.626 cfs
11/19/2002
Post-Development
GENERAL INFORMATION
Description: Drainage Basin Postdevelopment.
Drainage Area (1) = 8.620 acres
Drainage Area (2) =
Drainage Area (3) =
Drainage Area (4) =
Drainage Area (5) =
Total
Velocity of Runoff CV1) =
Coefficient of Runoff (C1) =
Velocity of Runoff (V;z) =
Coefficient of Runoff (C;z) =
Velocity of Runoff (V-3) =
Coefficient of Runoff (C3) =
Velocity of Runoff (V 4) =
Coefficient of Runoff (C4)=
Velocity of Runoff (V 5J =
Coefficient of Runoff (C5) =
Area 1 2 & 5
Total Area
Composite Velocity
Composite Coeffcient of Runoff
Composite Time of Concentration
Area 3 & 4
Total Area
Composite Velocity
Composite Coeffcient of Runoff
Composite Time of Concentration
2.070 acres
12.290 acres
5.070 acres
5.190 acres
33.240 acres
8.50 ft/sec
0.60
8.70 ft/sec
0.60
8.60 ft/sec
0.60
8.60 11isec
0.60
8.00 11/sec
0.60
15.88 acres
8.36 ft/sec
0.60
10.00 min
17.36 acres
8.60 11/sec
0.60
10.00 min
**NOTE: Minimum Tc allowed = 1 O min.
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q\
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.806
65
8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.785
76
8.5
10 YEAR FREQUENCY RATE OF DISCHARGE (Q\
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.763
80
8.5
25 YEAR FREQUENCY RATE OF DISCHARGE (Q\
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.754
89
8.5
50 YEAR FREQUENCY RATE OF DISCHARGE (Q\
Coefficient (e) = 0.745
Coefficient (b) = 98
Coefficient (d) = 8.5
100 YEAR FREQUENCY. RATE OF DISCHARGE (Q\
Coefficient (e) = 0.73
Coefficient (b) = 96
Coefficient (d) = 8
RESULT (Area 1,2 & 5)
Rainfall Intensity (l;z) = 6.327 in/hr
Rainfall Intensity (15! = 7 .693 in/hr
@fit IlIIIl : III :t ::::r~i~Ml:S!M t
Rainfall Intensity (110) = 8.635 in/hr __-
@@F . :: :: : ::: : rn~;~~~::1r1:: :•:::
Rainfall Intensity (125) = 9.861 in/hr
:s~~5 U:.:;;; ;;:;;;:;;;:;; ::::: •@hti~Mt¥
Rainfall Intensity (150) = 11.148 in/hr
@~@ : ;;;: Mt;Mq@f.¥.U
Rainfall Intensity (110o) =
RESULT (Area 3 & 4)
Rainfall Intensity (l;z) = 6.327 in/hr
@Wf : : : ~mM~Af.¥ ?
Rainfall Intensity (15J = 7 .693 in/hr
@~:§ ;: it : I ::t ;; iiiM~t~M~tilf
Rainfall Intensity (110) =
Rainfall Intensity (125) = 9.861 in/hr
9~~#: n: : : t : MM:.§t~ Mi t
Rainfall Intensity (150) = 11 .1 48 in/hr
@~~#: r ················· 1!1iiMiM¥ ··········
Rainfall Intensity (110o) = 11.639 in/hr
§~~~#: ; ; ; ;; ;;; :::::rn~~W#i~Mi<
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
11/19/2002
VOL=
VOL=
0
10
20
30
0
10
20
30
Post-Development (Area 1, 2 & 5) Pre-Development (Area 1)
2Y~R 5Y~R
0 0 0
60.781 15.686 73.908
30.391 7.843 36.954
0 0.000 0
40586
0
19.272
9.636
0.000
49172
25 YEAR 50 YEAR
0 0 0 0
94.743 24.901 107.100 28.214
47.372 12.451 53.550 14.107
0 0.000 0 0.000
62858 70998
10 YEAR
0
82.955
41 .478
0
21 .753
10.877
0.000
55082
0
100 YEAR
0
111 .822
55.911
0
0
29.436
14.718
0.000
74147
2-Year Hydrograph 5-Year Hydrograph
ii) 80 -...-----.-----...,------. ..... t,) -60 -1---~----+-----I
Cll El 40 -1---i' ca £ 20
Cl) c 0-"""""==
0 10 20
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
30
ii) 80 -...----.....------.------. .....
D Post-Development
D Pre-Development
~ 60 -1---
Cll
El 40 ca £ 20
i5 0
0 10 20
Time (min)
Project Manager: Lee Adams
Calculations: Mark Taylor
30
El Post-Development
D Pre-Development
11 /19/2002
10-Year Hydrograph 25-Year Hydrograph
en 1 oo -.------.------.,.-------. .... ~ 80 -1----
~ 60 +--
::a 40
"fi 20 (/)
Ci 0
0 10 20
Time (min)
30
D Post-Development
Cl Pre-Development
-100 (/) .... u 80 -Cl) 60 C'> .... 40 CV .c u 20 .!!? 0 Cl
0 10 20
Time (min)
30
Cl Post-Development
D Pre-Development
50-Year Hydrograph 100-Year Hydrograph
en 150 .... u -Cl) 100 Cl ....
CV 50 .c u (/)
Ci 0
0 10 20
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
30
~ 150
u -D Post-Development Cl) 100 C'> ....
Cl Pre-Development CV 50 .c u (/) c 0
0 10 20
Time (min)
Project Manager: Lee Adams
Calculations: Mark Taylor
30
Cl Post-Development
D Pre-Development
11/19/2002
Post-Development Area 1,2 &5
Inflow Hydrograph Ordinates
(Cubic Feet per Second)
Time 2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
(min) Storm Storm
0 0 0
1 6.08 7.39
2 12.16 14.78
3 18.23 22.17
4 24.31 29.56
5 30.39 36.95
6 36.47 44.34
7 42.55 51.74
8 48.62 59.13
9 54.70 66.52
J]1 jp ::: ': §9\7§ ::: : ]~;i1
11 57.74 70.21
12 54.70 66.52
13 51.66 62.82
14 48.62 59.13
15 45.59 55.43
16 42.55 51 .74
17 39.51 48.04
18 36.47 44.34
19 33.43 40.65
20 30 .39 36 .95
21 27.35 33 .26
22 24.31 29.56
23 21 .27 25.87
24 18.23 22.17
25 15.20 18.48
26 12.16 14.78
27 9.12 11 .09
28 6.08 7.39
29 3.04 3.70
30 0 0
Spring Meadows Subdivision
Job# 000387-3557
Storm Storm Storm Storm
0 0 0 0
8.30 9.47 10.71 11 .18
16.59 18.95 21.42 22.36
24.89 28.42 32.13 33 .55
33 .18 37.90 42.84 44.73
41.48 47.37 53 .55 55 .91
49.77 56.85 64.26 67.09
58.07 66.32 74.97 78.28
66.36 75.79 85.68 89.46
74.66 85.27 96.39 100.64
:t.~,?;$§ =: : @!!izif 19\7~19 :1:11 lac?.
78.81 90.01 101 .75 106.23
74.66 85 .27 96.39 100.64
70.51 80.53 91 .04 95 .05
66.36 75.79 85.68 89.46
62.22 71 .06 80.33 83.87
58.07 66 .32 74.97 78 .28
53.92 61 .58 69.62 72.68
49.77 56.85 64.26 67.09
45.63 52.11 58.91 61.50
41.48 47.37 53.55 55.91
37.33 42.63 48.20 50.32
33.18 37.90 42.84 44.73
29.03 33.16 37.49 39.14
24.89 28.42 32 .13 33.55
20.74 23.69 26.78 27.96
16.59 18.95 21.42 22.36
12.44 14.21 16.07 16.77
8.30 9.47 10.71 11 .18
4.15 4.74 5.35 5.59
0 0 0 0
Project Manager: Lee Adams
Calculations: Mark Taylor
ff!~
11 /19/2002
Pre-Development Area 1
Outflow Hydrograph Ordinates
(Cubic Feet per Second)
Time 2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
(min) Storm Storm Storm Storm Storm Storm
0 0 0 0 0 0 0
1 1.57 1.93 2.18 2.49 2.82 2.94
2 3.14 3.85 4.35 4.98 5.64 5.89
3 4.71 5.78 6.53 7.47 8.46 8.83
4 6.27 7.71 8.70 9.96 11 .29 11.77
5 7.84 9.64 10.88 12.45 14.11 14.72
6 9.41 11.56 13.05 14.94 16.93 17.66
7 10.98 13.49 15.23 17.43 19.75 20.61
8 12.55 15.42 17.40 19.92 22.57 23.55
9 14.12 17.34 19.58 22.41 25.39 26.49
: ]@p : : M:§.\@~ Jl 1$~Z7 .Ii?1 i7§ I ;4;go J .?@igj g&,~44,J]
11 14.90 18.31 20.67 23 .66 26.80 27.96
12 14.12 17.34 19.58 22.41 25.39 26.49
13 13.33 16.38 18.49 21 .17 23.98 25.02
14 12.55 15.42 17.40 19.92 22.57 23.55
15 11 .76 14.45 16.31 18.68 21 .16 22.08
16 10.98 13.49 15.23 17.43 19.75 20.61
17 10.20 12.53 14.14 16.19 18.34 19.13
18 9.41 11.56 13.05 14.94 16.93 17.66
19 8.63 10.60 11 .96 13.70 15.52 16.19
20 7.84 9.64 10.88 12.45 14.11 14.72
21 7.06 8.67 9.79 11 .21 12.70 13.25
22 6.27 7.71 8.70 9.96 11 .29 11 .77
23 5.49 6.75 7.61 8.72 9.87 10.30
24 4.71 5.78 6.53 7.47 8.46 8.83
25 3.92 4.82 5.44 6.23 7.05 7.36
26 3.14 3.85 4.35 4.98 5.64 5.89
27 2.35 2.89 3.26 3.74 4.23 4.42
28 1.57 1.93 2.18 2.49 2.82 2.94
29 0.78 0.96 1.09 1.25 1.41 1.47
30 0 0 0 0 0 0
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
11/19/2002
Channel
Depth vs. Volume
Elevation
(ft)
247.0
247.5
248.0
248.5
249.0
249.5
250.0
250.5
251 .0
251.5
252.0
252.5
253.0
253.5
254.0
254.5
8.0
7.0
-6.0 ;::= -5.0 = 4.0 a.
Q) 3.0
c 2.0
1.0
0.0
0
Depth Volume
(ft) (cf)
0.0 0.00
0.5 5101.25
1.0 10202.50
1.5 15303.75
2.0 20405.00
2.5 25506.25
3.0 30607.50
3.5 35708.75
4.0 40810.00
4.5 45911.25
5.0 51012.50
5.5 56113.75
6.0 61215.00
6.5 66316.25
7.0 71417.50
7.5 76518.75
Channel Depth vs. Volume
y = 1 E -04x /
~
/
~
~
~
~
~
20000 40000 60000 80000
Volume (cf)
100000
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
11/19/2002
Elevation
(ft)
247 .0
247 .5
248.0
248 .5
249.0
249.5
250.0
250.5
251 .0
251 .5
252.0
252.5
253.0
253.5
254.0
254.5
0.6
-0.5 ~ 0.4
£ 0.3
~ 0.2
c 0.1
0.0
8.0
g 6.0
£ 4.0 a. ~ 2.0
0.0
0.0
0.0
Outlet Control
Depth Velocity Discharge Inlet Velocity=
(ft) (ft/s) (cfs) Diameter=
0.0 0.00 0.00 Area=
0.5 10.10 12.30
1.0 11 .59 14.11
1.5 12.90 15.71
2.0 14.10 17.16
2.5 15.20 18.50
3.0 16.22 19.75
3.5 17.18 20.92
4.0 18.10 22.03
4.5 18.97 23 .09
5.0 19.80 24.10
5.5 20.59 25.07
6.0 21.36 26.00
6.5 22.10 26 .91
7.0 22.82 27.78
7.5 23.51 28 .63
Depth vs. Discharge
y = 0.0.1 06x
~
_i....------........... ___. .........
~
2.0 4.0 6.0 8.0 10.0 12.0 14.0
Discharge (cfs)
Depth vs. Discharge
y= 0.452x 5.7493 /
,/.
~ .......
-,,,,,,...
5.0 10.0 15.0 20.0 25.0 30.0 35.0
Discharge (cfs)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
8.36 ft/s
1 .25 ft
1.22 sq ft
11/19/2002
Depth
(ft)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
35.0
~ 30.0
~ 25.0
~ 20.0
; 15.0 ..c:
0 10.0 "' c 5.0
0.0
Storage Indication
Storage Discharge 2s/t 2s/t+O
(cf) (cfs) (cfs) (cfs)
0.00 0.00 0.00 0.00
5101 .25 12.30 170.04 182.34
10202.50 14.11 340.08 354.19
15303.75 15.71 510.13 525 .83
20405.00 17.16 680.17 697.33
25506.25 18.50 850.21 868.71
30607.50 19.75 1020.25 1040.00
35708.75 20.92 1190.29 1211.21
40810.00 22.03 1360.33 1382.36
45911 .25 23.09 1530.38 1553.46
51012.50 24.10 1700.42 1724.52
56113.75 25.07 1870.46 1895.53
61215.00 26.00 2040.50 2066.50
66316.25 26.91 2210.54 2237.45
71417.50 27.78 2380.58 2408.36
76518.75 28.63 2550.63 2579.25
Discharge vs. 2s/t+O
_.._
----............
~ r-
I
I
0.0 500.0 1000.0 1500.0 2000.0 2500.0 3000.0
2s/t+O ( cfs)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
11/19/2002
Inflow I Outflow Simulation
2-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 6.08 364.69 11 .26 13.05 0.90
2 12.16 1458.74 45.03 52.22 3.59
3 18.23 3282.17 101.32 117.49 8.08
4 24.31 5834.98 180.13 208.87 14.37
5 30.39 9117.15 289.07 318.74 14.83
6 36.47 13128.70 421 .92 453.32 15.70
7 42.55 17869.61 578.92 612.38 16.73
8 48.62 23339.90 760.08 795.91 17.92
9 54.70 29539.57 965.39 1003.91 19.26
10 60.78 36468.60 1194.86 1236.38 20.76
11 57.74 38109.69 1249.20 1291.44 21 .12
12 54.70 39386.09 1291.47 1334.26 21 .39
13 51 .66 40297.80 1321 .67 1364.85 21 .59
14 48.62 40844.83 1339.78 1383.21 21 .71
15 45.59 41027.18 1345.82 1389.32 21 .75
16 42.55 40844.83 1339.78 1383.21 21 .71
17 39.51 40297.80 1321 .67 1364.85 21 .59
18 36.47 39386.09 1291.47 1334.26 21 .39
19 33.43 38109.69 1249.20 1291.44 21 .12
20 30.39 36468.60 1194.86 1236.38 20.76
21 27.35 34462.83 1128.43 1169.09 20.33
22 24.31 32092.37 1049.93 1089.56 19.81
23 21 .27 29357.22 959.35 997.79 19.22
24 18.23 26257.39 856.70 893.79 18.55
25 15.20 22792.88 741 .97 777.56 17.80
26 12.16 18963.67 615.16 649.09 16.97
27 9.12 14769.78 476.27 508.38 16.06
28 6.08 10211 .21 325.30 355.44 15.07
29 3.04 5287.95 162.26 190.27 14.00
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
2-Year Storm Event
80.00
Vi' ~ 60.00
ml Inflow cu 40.00 ni ... D Outflow 3: 20.00 0 ii: 0.00
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth Elevation Velocity
(ft) (ft) (ft/sec)
0.00 247.00 0.00
0.04 247.04 0.74
0.15 247.15 2.95
0.33 247.33 6 .64
0.58 247.58 11 .81
0.91 247.91 12.18
1.31 248 .31 12.90
1.79 248 .79 13.74
2.33 249.33 14.72
2.95 249.95 15.82
3.65 250.65 17.05
3.81 250.81 17.35
3.94 250.94 17.57
4.03 251 .03 17.74
4.08 251 .08 17.83
4.10 251 .10 17.87
4.08 251 .08 17.83
4.03 251 .03 17.74
3.94 250.94 17.57
3.81 250.81 17.35
3.65 250.65 17.05
3.45 250.45 16.70
3.21 250.21 16.28
2.94 249.94 15.79
2.63 249.63 15.24
2.28 249.28 14.62
1.90 248.90 13.94
1.48 248.48 13.19
1.02 248.02 12.38
0.53 247.53 11.50
0.00 247.00 10.56
11/19/2002
Inflow I Outflow Simulation
5-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 7.39 443.45 13.69 15.87 1.09
2 14.78 1773.79 54.76 63.50 4.37
3 22.17 3991 .03 123.20 142.86 9.83
4 29.56 7095.17 222.11 250.90 14.39
5 36.95 11086.20 354.28 384.80 15.26
6 44.34 15964.13 515.82 548.45 16.32
7 51 .74 21728.95 706.73 741 .86 17.57
8 59.13 28380.67 927.01 965.03 19.01
9 66.52 35919.29 1176.67 1217.95 20.64
10 73.91 44344.80 1455.69 1500.63 22.47
11 70.21 46340.32 1521.77 1567.58 22.90
12 66.52 47892.38 1573.17 1619.65 23.24
13 62.82 49001 .00 1609.89 1656.85 23.48
14 59.13 49666.18 1631 .92 1679.16 23.62
15 55.43 49887.90 1639.26 1686.60 23.67
16 51 .74 49666.18 1631 .92 1679.16 23.62
17 48.04 49001 .00 1609.89 1656.85 23.48
18 44.34 47892.38 1573.17 1619.65 23.24
19 40.65 46340.32 1521.77 1567.58 22.90
20 36.95 44344.80 1455.69 1500.63 22.47
21 33.26 41905.84 1374.92 1418.80 21 .94
22 29.56 39023.42 1279.46 1322.10 21 .32
23 25.87 35697.56 1169.32 1210.51 20.60
24 22.17 31928.26 1044.50 1084.05 19.78
25 18.48 27715.50 904.99 942.71 18.86
26 14.78 23059.30 750.79 786.50 17.85
27 11 .09 17959.64 581.91 615.40 16.75
28 7.39 12416.54 398.34 429.43 15.55
29 3.70 6430.00 200.08 228.58 14.25
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
5-Year Storm Event
80.00
UI ~ 60.00
El Inflow ~ 40.00 ... El Outflow ~ 20.00 u::
0.00
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth Elevation Velocity
(ft) (ft) (ft/sec)
0.00 247.00 0.00
0.04 247.04 0.90
0.18 247.18 3.59
0.40 247.40 8.07
0.71 247.71 11.82
1 .11 248.11 12.53
1.60 248.60 13.40
2.17 249.17 14.43
2.84 249.84 15.61
3.59 250.59 16.96
4.43 251.43 18.46
4.63 251 .63 18.81
4.79 251 .79 19.09
4.90 251 .90 19.29
4.97 251 .97 19.41
4.99 251 .99 19.44
4.97 251 .97 19.41
4.90 251 .90 19.29
4.79 251 .79 19.09
4.63 251 .63 18.81
4.43 251.43 18.46
4.19 251.19 18.02
3.90 250.90 17.51
3.57 250.57 16.92
3.19 250.19 16.25
2.77 249.77 15.50
2.31 249.31 14.67
1.80 248.80 13.76
1.24 248.24 12.77
0.64 247.64 11 .70
0.00 247.00 10.56
11/19/2002
Inflow I Outflow Simulation
10-Year Storm Event
Time Inflow Volume 2s/t-0 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 8.30 497.73 15.37 17.82 1.23
2 16.59 1990.92 61 .46 71.27 4.90
3 24.89 4479.57 138.29 160.35 11 .03
4 33.18 7963.68 250.87 280.04 14.58
5 41.48 12443.25 399.22 430.33 15.55
6 49.77 17918.28 580.54 614.02 16.74
7 58.07 24388.77 794.82 831 .10 18.14
8 66.36 31854.72 1042.06 1081.59 19.76
9 74.66 40316.13 1322.27 1365.47 21 .60
10 82.96 49773.00 1635.45 1682.75 23.65
11 78.81 52012.79 1709.63 1757.89 24.13
12 74.66 53754.84 1767.32 1816.34 24.51
13 70.51 54999.17 1808.53 1858.09 24.78
14 66.36 55745.76 1833.25 1883.13 24.94
15 62.22 55994.63 1841.49 1891.48 25.00
16 58.07 55745.76 1833.25 1883.13 24.94
17 53.92 54999.17 1808.53 1858.09 24.78
18 49.77 53754.84 1767.32 1816.34 24.51
19 45.63 52012.79 1709.63 1757.89 24.13
20 41.48 49773.00 1635.45 1682.75 23.65
21 37.33 47035.49 1544.80 1590.90 23.05
22 33.18 43800.24 1437.66 1482.36 22.35
23 29.03 40067.27 1314.03 1357.12 21 .54
24 24.89 35836.56 1173.93 1215.18 20.63
25 20.74 31108.12 1017.34 1056.54 19.60
26 16.59 25881 .96 844.27 881 .20 18.47
27 12.44 20158.06 654.71 689.16 17.23
28 8.30 13936.44 448.67 480.42 15.88
29 4.15 7217.08 226.15 254.99 14.42
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
10-Year Storm Event
100.00
J!! 80.00 ~ 60.00 El Inflow .S! !! 40.00 El Outflow 3: 0 20.00 u::: 0.00
0 5 10 15 20 25 30
Time(min)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth Elevation Velocity
(ft) (ft) (ft/sec)
0.00 247.00 0.00
0.05 247.05 1.01
0.20 247.20 4.03
0.45 247.45 9.06
0.80 247.80 11 .98
1.24 248.24 12.78
1.79 248.79 13.75
2.44 249.44 14.90
3.19 250.19 16.23
4 .03 251 .03 17.74
4.98 251 .98 19.42
5.20 252.20 19.82
5.38 252.38 20.13
5.50 252.50 20.36
5.57 252.57 20.49
5.60 252.60 20.53
5.57 252.57 20.49
5.50 252.50 20.36
5.38 252.38 20.13
5.20 252.20 19.82
4.98 251 .98 19.42
4.70 251 .70 18 .94
4.38 251 .38 18.36
4.01 251.01 17.70
3.58 250.58 16.94
3.11 250.11 16.10
2.59 249.59 15.17
2.02 249.02 14.15
1.39 248 .39 13.04
0.72 247.72 11 .84
0.00 247.00 10.56
11/19/2002
Inflow I Outflow Simulation
25-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 9.47 568.46 17.55 20.35 1.40
2 18.95 2273.83 70.19 81.40 5.60
3 28.42 5116.12 157.94 183.14 12.60
4 37.90 9095.33 288.35 318.00 14.83
5 47.37 14211.45 457.78 489.65 15.94
6 56.85 20464.49 664.86 699.44 17.29
7 66.32 27854.44 909.59 947.38 18.89
8 75.79 36381 .31 1191.97 1233.45 20.74
9 85.27 46045.10 1512.00 1557.68 22.84
10 94.74 56845.80 1869.68 1920.04 25.18
11 90.01 59403.86 1954.39 2005.86 25.74
12 85.27 61393.46 2020.28 2072.62 26.17
13 80.53 62814.61 2067.35 2120.30 26.47
14 75.79 63667.30 2095.58 2148.90 26.66
15 71.06 63951 .53 2105.00 2158.44 26.72
16 66.32 63667.30 2095.58 2148.90 26.66
17 61.58 62814.61 2067.35 2120.30 26.47
18 56.85 61393.46 2020.28 2072.62 26.17
19 52.11 59403.86 1954.39 2005.86 25.74
20 47.37 56845.80 1869.68 1920.04 25.18
21 42.63 53719.28 1766.14 1815.15 24.50
22 37.90 50024.30 1643.78 1691.18 23.70
23 33.16 45760.87 1502.59 1548.14 22.78
24 28.42 40928.98 1342.57 1386.03 21 .73
25 23.69 35528.63 1163.73 1204.85 20.56
26 18.95 29559.82 966.06 1004.59 19.26
27 14.21 23022.55 749.57 785 .27 17.85
28 9.47 15916.82 514.25 546.87 16.31
29 4.74 8242.64 260.11 289.40 14.64
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
25-Year Storm Event
100.00
~ 80.00 ..!:!.. 60.00 lilllnflow ~ f!! 40.00 III Outflow ;:;::
0 20.00 u::
0.00
0 5 10 15 20 25 30
Time(min)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth Elevation Velocity
(ft) (ft) (ft/sec)
0.00 247.00 0.00
0.06 247.06 1.15
0.23 247.23 4.60
0.51 247.51 10.35
0.91 247.91 12.18
1.42 248.42 13.09
2.05 249.05 14.20
2.79 249.79 15.52
3.64 250.64 17.04
4.60 251 .60 18.76
5.68 252.68 20.68
5.94 252.94 21 .14
6.14 253.14 21.49
6.28 253.28 21 .75
6.37 253.37 21 .90
6.40 253.40 21 .95
6.37 253.37 21 .90
6.28 253.28 21 .75
6.14 253.14 21.49
5.94 252.94 21 .14
5.68 252.68 20.68
5.37 252.37 20.13
5.00 252.00 19.47
4.58 251 .58 18.71
4.09 251 .09 17.85
3.55 250.55 16.89
2.96 249.96 15.82
2.30 249.30 14.66
1.59 248.59 13.39
0.82 247.82 12.03
0.00 247.00 10.56
11/19/2002
Inflow I Outflow Simulation
50-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 10.71 642.60 19.84 23.00 1.58
2 21.42 2570.40 79.35 92.01 6.33
3 32.13 5783.40 178.53 207.03 14.25
4 42.84 10281 .60 327.64 357.80 15.08
5 53.55 16065.00 519.16 551 .84 16.34
6 64.26 23133.60 753.25 788.99 17.87
7 74.97 31487.40 1029.90 1069.26 19.68
8 85.68 41126.40 1349.11 1392.65 21 .77
9 96.39 52050.60 1710.88 1759.16 24.14
10 107.10 64260.00 2115.21 2168.79 26.79
11 101 .75 67151 .70 2210.97 2265.81 27.42
12 96.39 69400.80 2285.46 2341.26 27.90
13 91.04 71007.30 2338.66 2395.16 28.25
14 85.68 71971 .20 2370.58 2427.50 28.46
15 80.33 72292.50 2381 .22 2438.28 28 .53
16 74.97 71971 .20 2370.58 2427.50 28.46
17 69.62 71007.30 2338.66 2395.16 28.25
18 64.26 69400.80 2285.46 2341 .26 27.90
19 58.91 67151 .70 2210.97 2265.81 27.42
20 53.55 64260.00 2115.21 2168.79 26.79
21 48.20 60725.70 1998.17 2050.21 26.02
22 42.84 56548.80 1859.84 1910.08 25.12
23 37.49 51729.30 1700.24 1748.38 24.07
24 32.13 46267.20 1519.35 1565.13 22.89
25 26.78 40162.50 1317.19 1360.31 21.56
26 21.42 33415.20 1093.74 1133.94 20.10
27 16.07 26025.30 849.01 886.01 18.50
28 10.71 17992.80 583.00 616.52 16.76
29 5.35 9317.70 295.71 325.47 14.88
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
50-Year Storm Event
150.00
~ ~ 100.00 El Inflow .! ~ 50.00 El Outflow :;:
0 ii: 0.00
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth
(ft)
0.00
0.06
0.26
0.58
1.03
1.61
2.31
3.15
4.11
5.21
6.43
6.72
6.94
7.10
7.20
7.23
7.20
7.10
6.94
6.72
6.43
6.07
5.65
5.17
4.63
4.02
3.34
2 .60
1.80
0.93
0.00
Elevation Velocity
(ft) (ft/sec)
247.00 0.00
247.06 1.30
247.26 5.20
247.58 11 .70
248.03 12.39
248.61 13.42
249.31 14.68
250.15 16.17
251.11 17.88
252.21 19.83
253.43 22.00
253.72 22.52
253.94 22.92
254.10 23.21
254.20 23.38
254.23 23.44
254.20 23.38
254.10 23.21
253.94 22.92
253.72 22.52
253.43 22.00
253.07 21 .38
252.65 20.63
252.17 19.77
251 .63 18.80
251.02 17.71
250.34 16.51
249.60 15.19
248.80 13.76
247.93 12.22
247.00 10.56
11/19/2002
Inflow I Outflow Simulation
100-Year Storm Event
Time Inflow Volume 2s/t-O 2s/t+O Outflow
(min) (cfs) (cf) (cfs) (cfs) (cfs)
0 0.00 0.00 0.00 0.00 0.00
1 11 .18 670.93 20.71 24.02 1.65
2 22.36 2683.73 82.85 96.07 6.61
3 33.55 6038.39 186.41 216.15 14.87
4 44.73 10734.91 342.65 373.01 15.18
5 55.91 16773.30 542.62 575.60 16.49
6 67.09 24153.55 787.03 823.21 18.09
7 78.28 32875.67 1075.87 1115.84 19.98
8 89.46 42939.65 1409.16 1453.49 22.17
9 100.64 54345.49 1786.88 1836.15 24.64
10 111 .82 67093.20 2209.04 2263.84 27.40
11 106.23 70112.39 2309.02 2365.14 28.06
12 100.64 72460.66 2386.79 2443.92 28.57
13 95.05 74137.99 2442.34 2500.20 28.93
14 89.46 75144.38 2475.66 2533.96 29.15
15 83.87 75479.85 2486.77 2545.22 29.22
16 78.28 75144.38 2475.66 2533.96 29.15
17 72.68 74137.99 2442.34 2500.20 28.93
18 67.09 72460.66 2386.79 2443.92 28.57
19 61 .50 70112.39 2309.02 2365.14 28.06
20 55.91 67093.20 2209.04 2263.84 27.40
21 50.32 63403.07 2086.83 2140.04 26.60
22 44.73 59042.02 1942.41 1993.72 25.66
23 39.14 54010.03 1775.77 1824.90 24.57
24 33.55 48307.10 1586.91 1633.57 23.33
25 27.96 41933.25 1375.83 1419.72 21 .95
26 22.36 34888.46 1142.53 1183.37 20.42
27 16.77 27172.75 887.01 924.50 18.75
28 11.18 18786.10 609.27 643.13 16.93
29 5.59 9728.51 309.32 339.25 14.96
30 0.00 0.00 -12.85 12.85 12.85
Inflow/Outflow Simulation
100-Year Storm Event
150.00
E' ~ 100.00 ~ El Inflow
!'!! 50.00 El Outflow :;:
0 u:::
0.00
0 5 10 15 20 25 30
Time (min)
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
Depth Elevation Velocity
(ft) (ft) (ft/sec)
0.00 247.00 0.00
0.07 247.07 1.36
0.27 247.27 5.43
0.60 247.60 12.22
1.07 248.07 12.47
1.68 248.68 13.55
2.42 249.42 14.86
3.29 250.29 16.41
4.29 251.29 18.21
5.43 252.43 20.24
6.71 253.71 22.51
7.01 254.01 23.05
7.25 254.25 23.47
7.41 254.41 23.76
7.51 254.51 23.94
7.55 254.55 24.00
7.51 254.51 23.94
7.41 254.41 23.76
7.25 254.25 23.47
7.01 254.01 23.05
6.71 253.71 22.51
6.34 253.34 21.85
5.90 252.90 21.08
5.40 252.40 20.18
4.83 251 .83 19.16
4.19 251 .19 18.03
3.49 250.49 16.77
2.72 249.72 15.40
1.88 248.88 13.91
0.97 247.97 12.29
0.00 247.00 10.56
11/19/2002
Storm Simulation Synopsis
2-Year 5-Year 10-Year 25-Year 50-Year
Storm Depth (ft) 4.10 4.99 5.60 6.40 7.23
Storm Elevation (ft) 251 .10 251 .99 252.60 253.40 254.23
Storm Volume (cf) 41027.18 49887.90 55994.63 63951 .53 72292.50
Supplied Capacity (cf) 76518.75 76518.75 76518.75 76518.75 76518.75
Percent of Capacity 54% 65% 73% 84% 94%
Supplied Freeboard (ft) 3.90 3.01 2.40 1.60 0.77
Channel Storage Volume as Percent of Maximum Volume
100%
90%
QI 80%
E :i 70% 0 >
E 60% :i E ')( 50% ta ::?: -40% 0 c QI 30% CJ ... QI a.. 20%
10%
0% 2-Year 5-Year 10-Year 25-Year 50-Year 100-Year
Design Storm
Spring Meadows Subdivision
Job# 000387-3557
Project Manager: Lee Adams
Calculations: Mark Taylor
100-Year
7.55
254.55
75479.85
76518.75
99%
0.45
11/19/2002
Inlet Sizing
10-Year Storm Event
Inlet# Length Area Flowrate
(ft) (acres) (cfs)
A1 8' 0.9447 6.199
A2 10 2.4828 13.840
A3 s 0.80S7 S.110
A4 10 2.439S 13.SOO
AS 7 1.6414 9.47S
[81 s 0.848 S.331_
82 s 1.09S4 6.623
01 8 1.9262 10.964
" 02 a 1.9327 10.097
03 7 1.4 796 8.887
04 7 1.S719 8.779
ff s 0.9381 S.7S1
06 s 0.6027 3.871
07 11 2.6S36 14.7S1
08 s 0.44 3.200
09 s 0.4704 3 .439 ~
F1 10 2.4S2 13.47S
Inlet Sizing
100-Year Storm Event
Inlet# Length Area
(ft) (acres)
A1 8 0.9447
A2 10 2.4828
A3 s 0.80S7
A4 10 2.439S
AS 7 1.6414
81 s 0.848
82 s 1.09S4
01 8 1.9262
02 8 1.9327
03 7 1.4 796
04 7 1.S719
OS s 0.9381
06 s 0.6027
07 11 2.6S36
08 s OA4
09 s 0.4704
F1 10 2.4S2
Spring Meadows Subdivision
Job# 000387-3SS7
Flowrate
(cfs)
9.978
17.483
8.S10
17.178
11 .SS8
8.9S.7
7.713
13.S64
13.609
10.419
11 .069
6.606
6.366
18.686
4.648
4.969
17.266
Project Manager: Lee Adams
Calculations: Mark Taylor
11/19/2002
'· .. ·:-·: .. '..,
.. • -::-
. . ......... -·· .... ··-. . .... -............... ,. ........................ -............... ~ ......... ·-........ ~ .......... --· .... -.--..... ~--·--
,,..4' .. " \' \. '· .. \.\··. '·
c I
~~
Section Flowrate Length
(cfs) (ft)
A1-J1 8.24 360
A2-J1 18.40 75
J1 -J2 26.65 168
J2-A3 26.65 100
A3-J3 33.45 212
A4-J3 17.96 60
J3-A5 51.40 240
A out 64.01 153
81-82 8.81 98
82-J2 15.90 160
J2-J1 15.90 63
05-06 7.65 90
06-J1 12.80 285
J1-08 28.70 315
07-08 19.62 75
08-09 48.32 160
...___ P D9-H1 40
Oout f-120
01-02 75
02-03 28.01 405
04-03 11 .68 75
03-J1 51 .50 240
F1 -J1 17.92 92
J1-J2 69.42 20
J2-G1 69.42 60
G1 -G2 69.42 80
Oout 69.42 468
Spring Meadows Subdivision
Job# 000387-3557
Slope
(ft/ft)
0.01047
0.02773
0.01429
0.01030
0.01519
0.01150
0.01029
0.01444
0.00225
0.00425
0.00397
0.00356
0.00333
0.00292
0.00573
0.00731
~600 0~3
0.01405
0.00635
0.02133
0.00583
0.01848
0.00750
0.00750
0.01738
0.00500
Pipe Sizing
10-Year Storm Event
Diameter
(in)
30
30
30
36
36
30
42
42
30
30
30
30
36
36
36
~ 6
30
36
36
42
42
42
42
42
42
Upstream Invert Downstream Invert
(ft) (ft)
269.30 265.53
267.25 265.17
264.90 262.50
261 .80 260.77
260.70 257.48
258.25 257.56
256.87 254.40
254.30 252.09
254.45 254.23
254.20 253.52
253.50 253.25
253.79 253.47
253.44 252.49
252.39 251.47
251 .90 251 .47
251 .37 250.20
250.11 249.87
249.84 249.50
253.96 252.92
252.29 249.72
251 .90 250.30
249.26 247.86
249.62 247.92
247.84 247.69
247.67 247.10
247.63 246.24
246.24 243.90
Project Manager: Lee Adams
Calculations: Mark Taylor
Upstream HGL Downstream HGL
(ft) (ft)
270.41 267.66
268.81 267.38
266.70 264.11
263.56 263.47
262.46 259.82
260.18 259.82
259.05 257.71
256.48 254.27
256.20 256.00
255.69 255.29
255.21 255.03
256.10 255.89
255.69 255.03
254.90 254.39
254.56 254.39
253.32 253.12
252.20 252.21
251 .92 251.36
255.38 254.68
254.25 252.49
253.52 252.59
252.03 251 .05
252.23 251.05
250 .84 250.76
250.54 250.30
249.80 248.99
248.54 246.07
12/2/02
Weir Diameter
From Bernouli's Equation, the velocity at capacity is:
V= 24.189 ft/s
Flowrate: Q=VA
Q= flowrate in cfs
V= velocity in ft/s
A= area of whole in sq ft
Q= 29.436 cfs
V= 24.189 ft/s
The area of the Weir exit is:
A= 1.217 sq ft
The circular Weir exit diameter is:
Spring Meadows Subdivision
Job# 000387-3557
D= 14.937 in
Project Manager: Lee Adams
Calculations: Mark Taylor
10/25/02
Pipe Sizing
100-Year Storm Event
Section Flowrate Length
(cfs) (ft)
A1-J1 13.27 360
A2-J1 23.25 75
J1-J2 36.52 168
J2-A3 36.52 100
A3-J3 47.84 212
A4-J3 22.85 60
J3-A5 70.69 240
A out 86.06 153
81-82 11 .91 98
82-J2 22.17 160
J2-J1 22.17 63
05-06 8.79 90
06-J1 17.25 285
J1-08 39.42 315
07-08 24.85 75
08-09 64.28 160
09-H1 70.89 40
Oout 70.89 120
01-02 18.04 75
02-03 36.14 405
04-03 14.72 75
03-J1 64.72 240
F1-J1 22.96 92
J1-J2 87 .68 20
J2-G1 87 .68 60
G1-G2 87.68 80
Oout 87.68 468
Spring Meadows Subdivision
Job# 000387-3557
Slope Diameter
(ft/ft) (in)
0.01047 30
0.02773 30
0.01429 30
0.01030 36
0.01519 36
0.01150 30
0.01029 42
0.01444 42
0.00225 30
0.00425 30
0.00397 30
0.00356 30
0.00333 36
0.00292 36
0.00573 36
0.00731 36
0.00600 36
0.00283 36
0.01405 30
0.00635 36
0.02133 36
0.00583 42
0.01848 42
0.00750 42
0.00750 42
0.01738 42
0.00500 42
Project Manager: Lee Adams
Calculations: Mark Taylor
12/2/02