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P&Z CASE NO.: m ' (7)01
DATE SUBMITTED: K. OD {71
CITY OF COLLEGE STATION
Planning & Development Services
FINAL PLAT APPLICATION
(Check one) D Minor D Amending
($300.00) ~OJ,(>O)
Is this plat in the ET J? D Yes ~No
[g" Fin~..lt-1 D Vacating
($400.00 vif ./ ($400.00)
D Replat
($600.00)*
The following items must be submitted by an established filing deadline date for P&Z consideration.
MINIMUM SUBMITTAL REQUIREMENTS:
,,/ $400 Filing Fee (see above) NOTE: Multiple Sheets -$55.00 per additional sheet
;-.i/A-$100 Variance Request to Subdivision Regulations (if applicable)
i,/ $200 Development Permit Application Fee (if applicable).~
~,....--$600.00 Infrastructure Inspection Fee (applicable if any pu~i~ infrastructure is being constructed)~
~Application completed in full.
f}.1jA Copy of original deed restrictions/covenants for replats (if applicable).
~/ Fourteen (14) folded copies of plat. (A signed mylar original must be submitted after staff review.) ~ Paid tax certificates from City of College Station, Brazos County and College Station l.S.D. 17 __ A copy of the attached checklist with all items checked off or a brief explanation as to why they are not.
V Two (2) copies of public infrastructure plans associated with this plat (if applicable).
Nf&"Parkland Dedication requirement approved by the Parks & Recreation Board, please provide proof of
approval (if applicable). (Parkland approval letter submitted with final plat.)
Date of Preapplication Conference: November 8 2006 ____________ .........,, _______________________ ~
NAME OF SUBDIVISION The Lofts. Wolf Pen Creek -Lot 1 . Block 1 & Lot 1. Block 2
APPLICANT/PROJECT MANAGER'S INFORMATION (Primary Contact for the Project):
Name Natalie Ruiz. IPS Group
Street Address 511 University Drive East. Suite 205 City College Station
State Texas Zip Code 77840 --------
Phone Number 979-846-9259
E-Mail Address natalie@ipsgroup.us
Fax Number 979-260-3564
PROPERTY OWNER'S INFORMATION (ALL owners must be identified. Please attach sheet for multiple owners):
Name Mark Lindley, Asset Plus Corporation
Street Address 5151 San Felipe, Suite 2050 City "--'H=o-'='u=st=o;..;..n=--------
State Texas Zip Code 77056 -----------
Phone Number (713) 268-5122
ENGINEER'S INFORMATION:
E-Mail Address mlindley@assetpluscorp.com
Fax Number (713) 268-5111
Name Veronica J. B. Morgan. P.E., C.F.M., Mitchell & Morgan
Street Address 511 University Drive East. Suite 204 City College Station
State Texas Zip Code 77840
Phone Number (979) 260-6963
E-Mail Address v@mitchellandmorgan.com
Fax Number (979) 260-3564
I of5
Do any deed restrictions or covenants exist for this property? _..!..N!!./A!....!.....----------------
ls there a temporary blanket easement on this property? The temporary blanket easement request was
submitted to the City on Friday, August 3. 2007. To date. it has not been filed for record.
Acreage-Total Property 1.909 acres Total # of Lots 2 -=----R-0-W Acreage 0.474 acres
Existing Use: -=-V-=a:..:c;.:::a"'"'n..:....t ____ _ Proposed Use: The Lofts. Wolf Pen Creek Mixed-Use Dev'I
Number of Lots By Zoning District 2 I WPC ---'------'---
Average Acreage Of Each Residential Lot By Zoning District: 0.954 acres
Floodplain Acreage __;O:..._ ____ _
A statement addressing any differences between the Final Plat and approved Master Plan and/or Preliminary Plat (if
applicable}: No significant changes between the preliminary plat & final plat.
Requested Variances To Subdivision Regulations & Reason For Same: No requested variances.
Requested Oversize Participation: The owner is requesting oversize participation for the construction of
Manuel Drive through the subject property. We are reviewing the engineer's estimates now and will
submit a formal request as soon as possible.
Total Linear Footage of
Proposed Public:
318.4' Streets
633.15' Sidewalks
0 Sanitary Sewer Lines
0 Water Lines
0 Channels
31.5' Storm Sewers
0 Bike Lanes I Paths
Parkland Dedication due prior to filing the Final Plat:
ACREAGE:
The Parks Director has authorized a fee in lieu of land
dedication. All parkland fees will be paid as directed by the
Parks Board. No parkland fees are due with the final plat.
OR
FEE IN LIEU OF LAND:
___ #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
final plat and attests that this request does not amend any covenants or restrictions associated with this plat.
Signature and Title Date
2 ofS
SUPPLEMENTAL DEVELOPMENT PERMIT INFORMATION
Application is hereby made for the following development specific site/waterway alterations:
ACKNOWLEDGMENTS:
I' /<J
1 Pi fDhl ( (' A 5 .-P . IJ/l(f?£--z 'thy/ , design engineer/owner, hereby acknowledge or affirm that:
The information and conclusions contained in the above plans and supporting documents comply with the current
require nts of the City of College Station, Texas City Code, Chapter 13 and its associated Drainage Policy and Design
Standa d . As a condition of approval of this permit application, I agree to construct the improvements proposed in this
appli · n according to hese documents and the requirements of Chapter 13 of the College Station City Code.
Contractor
CERTIFICATIONS: (for prop d alterations within designated flood hazard areas.)
;
A. I, t\IA 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
f-J f A 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
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.
CITY OF COLLEGE STATION
PL:mning & Dewlopmmt Scrvicn
SITE LEGAL DESCRIPTION:
The Lofts
Lot 1, Block 1 and
Lot 1, Block 2
DATE OF ISSUE: 10/16/07
OWNER:
DEVELOPMENT PERMIT
PERMIT NO. 07-72
FOR AREAS OUTSIDE THE SPECIAL FLOOD HAZARD AREA
RE: CHAPTER 13 OF THE COLLEGE STATION CITY CODE
SITE ADDRESS:
2240 Dartmouth Street
DRAINAGE BASIN:
Wolf Pen Creek
VALID FOR 9 MONTHS
CONTRACTOR:
Asset Plus Corporation c/o Mark Lindley
5151 San Felipe, Suite 2050
Houston, Texas 77056
TYPE OF DEVELOPMENT:
SPECIAL CONDITIONS:
Full Development Permit
All construction must be in compliance with the approved construction plans
All trees required to be protected as part of the landscape plan must be completely barricaded in accordance with Section
7.5.E., Landscape/Streetscape Plan Requirements of the City's Unified Development Ordinance, prior to any operations of
this permit. The cleaning of equipment or materials within the drip line of any tree or group of trees that are protected and
required to remain is strictly prohibited. The disposal of any waste material such as, but not limited to, paint, oil, solvents,
asphalt, concrete, mortar, or other harmful liquids or materials within the drip line of any tree required to remain is also
prohibited.
**TCEQ PHASE II RULES IN EFFECT**MANUEL DRIVE CONSTRUCTION AND STORM SEWER IMPROVEMENTS**
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.
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 outside 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.
Date
Date
LETTER OF COMPLETION
CITY ENGINEER
CITY OF COLLEGE STATION
COLLEGE STATION, TEXAS
RE: COMPLETION OF Lof h _ f2 l/JrJ/.f Petti Crt€k
Dear Sir:
The purpose of our letter is to request that the following listed improvements be
approved and accepted as being constructed under City Inspection and completed
according to plans and specifications as approved and required by the City of College
Station, Texas. This approval and acceptance by the City Is requested In order that we
may finalize any subcontracts and to affirm their warranty on the work. This approval
and acceptance by the City of the improvements listed below does hereby void the letter
of guarantee for the listed Improvements on the above referenced project.
The on.e-year warranty is hereby affirmed and agreed to byL~sk~-M b1kpri ~e 5 1 ,/;Jvc-.
and by their subcontractors as indicated by signatures below.
WORK COMPLETED
-. 7 /c>~A ~ _ lrJAte~
,. A-J)d-J"rtiv OF ~ID6tJJ_~µlS. ~
/10 l.Ltf'll-"tv I p tt-ftr M0"1H;
Owner:
Phone Number: {7J J) 7Bl "S Bvo
Address: SI 5 I ~AN !~1.-rft
GiJdc io~O
City Engineer
Ravis1d 1131/07
:tJt\BRANTY DATE
__ 1 /1 '1 Lo1
8 ,~~' /oq __ ,,...,_I ..,... I
-·-------
Contractor: Lo.NsTQvcJ;D/0 &r&12f>/2/5t?, f;vc
Phone Number: b/)-33L.-8teo
Address: 32..S-5e-t/OO..t1LD LcmP
F MNJ<-L-JN I TN 370b 7
/;-.l1 (I
i:..::3LPLAT FILED
_ 1'-lA OFFSITE ESMTS FILED
TEMP BLANKET ESMT FILED
0 OTHE.R A;,SMTS NEEDED >f~tu ~;;!.zl jzc~~ ~ VV/ 'I: ~vu.. j /('. ( ~
SOP: Filing of Final Plats -Letters of Completion 7/07/09
Inspectors shall confirm the following and include associated comments on the punchlist as
necessary before forwarding Letter of Completion to development review engineer:
0 ontact Donnie Willis (0: 764-6375, C: 229-7632) for outstanding Erosion/Drainage issues,
~ _,,£ontact Gilbert Martinez (0: 764-6255) for outstanding CS Electric and Streetlights,
if' coordinate fire flow analyses with CS Water Services (or the design engineer for non-city
utilities) and confirm test results meets minimum requirements with the development
1~eview engineer, ;f ~or BTU service area, contact Tom Brent at : 821-5773 for outstanding BTU Electric and fl, Streetlights. In Tom's absence, John Fontinoe or their supervisor Randy Trimble can be
ontacted at O: 821-5728.
fl or BTU service area, confirm with development review engineer that service agreement is
I' rn place with BTU,
. ~for other non-city utility service areas (Wellborn Water SUD, Brushy Creek SUD, Wickson . ~ f I Creek SUD, etc) confirm with development review engineer that infrastructure is complete
/cmd for outstanding issues, V require that 2 copies of Red-lined Record Drawings be provided for all Public Infrastructure
with the following attestation:
"I, , General Contractor for development, certify that the
improvements shown on this sheet were actually built, and that said improvements are
shown substantially hereon. I hereby certify that to the best of my knowledge, that the
materials of construction and sizes of manufactured items, if any are stated correctly
hereon."
General Contractor
o require that 2 copies of Red-lined Record Drawings be provided for all Public Drainage
Infrastructure including Private Detention Facilities with the following attestations:
"I hereby attest that I am familiar with the approved drainage plan and associated
construction drawings and furthermore, attest that the drainage facilities have been
constructed within dimensional tolerances prescribed by the Bryan & College station
Unified Stormwater Design Guidelines and in accordance with the approved construction
plans or amendments thereto approved by the City of College Station."
(affix seal) Licensed Professional Engineer
State of Texas No. ___ _
"I certify that the subdivision improvements shown on this sheet were actually built, and
that said improvements are substantially as shown hereon. I further certify, to the best of
my knowledge, that the materials of construction and sizes of manufactured items, if any,
are stated correctly hereon."
General Contractor
Manuel Drive Extension Engineer's Estimate
October 2007
REQUESTED PUBLIC INFRASTRUCTURE • 38' ROAD
lllm. Pt!Cr!o!lon llo.ll ~ ll!!l.t.km GENERAL ITEMS
1 Prepare Rlghl·of·Way LS 1 s 2 Mobilization LS 1 s
3 Cellulose Fiber Mulch Seeding SY 336 s 4 Erosion & Sediment Control LS 1 s
PAVEMENT ITEMS
5 6" Lime Treated Subgrade SY 2315 $
6 6" Reinforced Concrete Paving (4000 psi) SY 1385 s
7 Wheelehair Ral\'l)S EA 2 s e 4" Reinforced Concrete Sidewalk • 6' Wide SF 3953 s
STORM SEWER ITEMS
9 24" RCP (Class Ill) In Structural Backfill LF 75 $
10 30" RCP (Class llf) In Structural Backfill LF 355 $
11 Standard Junction Box EA 2 $
12 Standard 10' Recessed Inlet EA 2 $
13 Standard 15' Recessed Inlet EA 2 s
ELECTRICAL ITEMS
14 Slreet Light Foundation EA 4 s
15 Street Light Cooduil·2" Grey PVC LF 318 s
16 Street Light ·Cobra Head Bronze EA 4 s
7,270.00
14,540.00
0.50
4,000.00
Subtotal
3.25
45.00
700.00
5.00
Subtotal
55.00
75.00
3,000.00
2,600.00
3,600.00
Subtot•I
500.00
5.00
2,500.00
Subtotal
15% Con!lngency
TOTAL
REQUIRED PUBLIC INFRASTRUCTURE • 27' ROAD
!ttm Dncrlotlon llo.ll lll!iJllJ1y ~
GENERAL fIEMS
1 Prepare Right-of-Way LS 1 s 6,888.65
2 MobitizaUon LS 1 s 13,777.30
3 Cellulose Fiber Mulch Seeding SY 336 $ 0.50
4 Erosion & Sediment Control LS 1 $ 4,000.00
Subtotal
PAVEMENT ITEMS
5 6" Lime Treated Subgrade SY 1900 s 3.25
6 6" Reinforced Concrete Paving (4000 psi) SY 985 $ 45.00
7 Wheelchair Ra"l>S EA 2 $ 700.00 a 4" Reinforced Concrete Sidewalk· 6' Wide SF 3953 $ 5.00
Subtotal
STORMSEWER ITEMS
9 24" RCP (Class Ill) in Structural Backfill LF 75 s 55.00
10 30" RCP (Class l!I) in Structural Baci<fill LF 355 $ 75.00
11 Standard Junction Box EA 2 $ 3,000.00
12 Standard 1 O' Recessed lnlel EA 2 s 2.600.00
13 Standard 15' Recessed Inlet EA 2 $ 3.600.00
Subtot•I
ELECTRICAL ITEMS
14 Street Ughl Foundation EA 4 s 300.00
15 Slreet Lighl Condult-2" Grey PVC LF 318 $ 5.00
16 Slreel Lighl • Cobra Head Bronze EA 4 $ 2,500.00
Subtotal
15% ConUng•ncy
TOTAL
l1tm Pt!Crlo!lon .llnll ~ ~ ~T!l~liI !!Ii!§ BliQl.!!!lliQ llY ~!IY 1 38' Street· TOTAL COST LS $ 203.420.01
Total
llBlili.I CI!iMli Blis;ILl1Bli12 ID'. 121iY~Q~Miit!T 3 2r S1reet • TOTAL COST LS $ 179,104.90
Total
&n21!!ll
$
$
$
$
$
s s s s
$
s
$ s
$ s
$
s s
$ s
s
s
&!!2llru
$
$
$ s s
s
$
$
$ s
$
$
$ s
$
$
$
$
$
$
s
$
&n2l!.!!1
$
s
s
$
30% of Required Costs S
7,270.00
14.540.00
168.00
4 000.00
25,976.00
7.523.75
62,325.00
1,400.00
19.765.00
91,013.75
4,125.00
26,625.00
6.000.00
5,200.00
7,200.00
49, 150.00
2.000.00
1,590.00
10,000.00
13,5ll0.00
23,688.26
203,420.01
6,888.65
13.777.30
168.00
4,000.00
24,133.115
6.175.00
44.325.00
1,400.00
19.765.00
11,aS5.oo
4.125.00
26.625.00
6,000.00
5,200.00
7.200.00
,9, 150.00
1,200.00
1.590.00
10.000.00
12,7llO.OO
20,665.95
17f, 11U.ll0
Manuel Drive Extension Engineer's Estimate
October 2007
REQUESTED PUBLIC INFRASTRUCTURE • 38' ROAD
Item Description Unit ~ Unit Cost
GENERAL ITEMS
1 Prepare Right-of-Way LS 1 $
2 Mobilization LS 1 $
3 Cellulose Fiber Mulch Seeding SY 336 $
4 Erosion & Sediment Control LS 1 $
PAVEMENT ITEMS
5 6" Lime Treated Subgrade SY 2315 $
6 6" Reinforced Concrete Paving (4000 psi) SY 1385 $
7 Wheelchair Ramps EA 2 $
8 4" Reinforced Concrete Sidewalk -6' Wide SF 3953 $
STORM SEWER ITEMS
9 24" RCP (Class Ill) in Structural Backfill LF 75 $
10 30" RCP (Class Ill) in Structural Backfill LF 355 $
11 Standard Junction Box EA 2 $
12 Standard 1 O' Recessed Inlet EA 2 $
13 Standard 15' Recessed Inlet EA 2 $
ELECTRICAL ITEMS
14 Street Light Foundation EA 4 $
15 Street Light Conduit-2" Grey PVC LF 318 $
16 Street Light -Cobra Head Bronze EA 4 $
~
7,270.00 $
14,540.00 $
0.50 $
4,000.00 $
Subtotal $
3.25 $
45.00 $
700.00 $
5.00 s
Subtotal $
55.00 $
75.00 $
3,000.00 $
2.600.00 $
3,600.00 $
Subtotal $
500.00 $
5.00 $
2,500.00 $
Subtotal $
15% Contingency $
TOTAL $
7,270.00
14,540.00
168.00
4,000.00
25,978.00
7,523.75
62,325.00
1,400.00
19,765.00
91,013.75
4,125.00
26,625.00
6,000.00
5,200.00
7,200.00
49,150.00
2,000.00
1,590.00
10,000.00
13,590.00
23,688.26
203,420.01
Josh Norton, EIT
City of College Station
Development Services
PO Box 9960
College Station, TX 77842
MITCHELL
MM
MORGAN
RE: The lofts, Wolf Pen Creek lot 1, Block 1 & lot 1, Block 2
Dear Josh:
September 17, 2007
The purpose of this letter is to acknowledge that the construction plans for the streets and
drainage for The Lofts, Wolf Pen Creek Lot 1, Block 1 & Lot 1, Block 2, to the best of my
knowledge only deviate from the B/CS Design Guidelines Manual in the following two (2)
instances.
•!• We have a previously granted variance to the centerline radius of Manuel Drive.
•!• And we would request to vary from the standard depth of the recessed inlet box only on
Dartmouth Drive from 2.6ft to that necessary to accommodate the exi sting storm sewer
pipe in the Dartmouth Drive ROW
I also acknowledge, to the best of my knowledge that the details provided in the construction plans
are in accordance with the Bryan/College Station Standard Details, with the only exception being
that described above.
If you have any comments, or would like to discuss this further, please feel free to contact me.
Veronica J.B. or
Managing Partner
cc: file
511 UNIVERSITY DRIVE EAST, SUITE 204 • COLLEGE STATION, TX 77840 • T 979.260.6963 • F 979.260.3564
CIVIL ENGINEERING • HYDRAULICS • HYDROLOGY • UTILITIES • STREETS • SITE PLANS • SUBDIVISIONS
info@mitchellandmorgan.com • www.mitchellandmorgan.com
CITY OF COLLEGE STATION
KeyBank Real Estate Capital
Lakes on Post Oak
3050 Post Oak Blvd., Suite 500
Houston, TX 77056
October 8, 2007
RE : Proposed Cambridge Lofts located at the intersection of Dartmouth and
Holloman Drive in College Station , Texas.
To Whom It May Concern:
This letter is in regards to your request for verification of water availability for the
property located at the southwest corner of the Dartmouth and Holloman Drive in
College Station, Texas.
Water: There are two 8-in mains located at the southern corner of the
property and a 12-in main in the ROW of Richards Street, near the mid
point of the southwest property line.
Please feel free to contact me if you need any additional information .
Sincerely,
(Jfi~
Carol L. Cotter, EIT
Graduate Civil Engineer
Cc: File
the heart of the Research Valley
P.O. BOX 9960
1101 TEXAS AVENUE
COLLEGE STATION• TEXAS• 77842
979.764.3510
www.cstx.gov
MITCHELL
M M
MORGAN
October 5, 2007
Carol Cotter
City of College Station
Development Services
1101 Texas Avenue
P.O. Box 9960
College Station, Texas 77842
RE: Engineering Comments for the lofts -Manuel Drive Extension
Attached are the following items and responses to your comments:
• One (1) copy of revised HGL Calculations and Profiles (Sheet 01, 02, and 03)
• One (1) revised copy of the Manuel Drive construction plans
ENGINEERING COMMENTS NO 2
1. COMMENT: Why are the CA values different for PA 1.1 and PA 1.2 between Exhibit 4 and 8?
ANSWER: Exhibit 4 was used for pipe sizing calculations for Manuel Drive assuming NO
development of the Lofts on Block 2 Lot 1 . At the time of this report, detention
calculations for the Lofts were not yet being studied, rather the pipes were being
sized for Manuel Drive only. Because we were not including any assumptions for
the Lofts development we matched the downstream pipe size to provide as much
extra capacity as possible for the future Lofts. Initially, we assumed that we would
not need to modify the storm sewer system in Dartmouth Drive. Since the
receiving system is only a 24" diameter pipe that size was chosen for the Manuel
Drive storm system and then it was checked to assure it had sufficient capacity for
the Manuel Drive flows. In the event of excess capacity in that system it would be
available for the Lofts townhouse development on Block 2, Lot 1 as the drainage
system for that site was developed.
However, we did include an increased impervious cover (we assumed greater than
85% impervious cover for Block 2, Lot 1) on the HGL calculations in Exhibit 8. This
was to assure that the system could work with some increased runoff from Block 2,
Lot 1 and to ascertain how much excess capacity the system may have . This was to
be refined with the Lofts drainage report as we discussed how that site would
drain and if the downstream system had capacity.
As you will see in answer #3 because of the 6" HGL freeboard requirement and
that we have to "dry up" the intersection, we will have to increase the storm line
size along Dartmouth to meet these requirements.
511 UNIVERSITY DRIVE EAST, SUITE 204 • COLLEGE STATION, TX 77840 • T 979.260.6963 • F 979.260.3564
CIVIL ENGINEERING • HYDRAULICS • HYDROLOGY • UTILITIES • STREETS • SITE PLANS • SUBDIVISIONS
info@mitchellandmorgan.com • www.mitchellandmorgan.com
2. COMMENT: Why is all of EA-3 not included in post development calculations for PA 1.3?
ANSWER : The design of the Lofts will remove this area from the drainage basin of the 30 "
storm sewer under Dartmouth and divert it to the 2-36" storm sewer pipes under
Holleman. This system will be further studied with the Lofts at Wolf Pen Creek
Drainage Report to be submitted with the Lofts at Wolf Pen Creek Construction
drawings.
3. COMMENT: Is the hydraulic grade line at least 0.5 feet below the inlet opening elevation? Not
sure how this correlates to "MH Top Upstream". Please provide profiles of
hydraulic gradeline.
ANSWER: The HGL is NOT 0.5 feet below all the inlet opening elevations on Dartmouth Drive.
Please see the attached Sheets 01 and 02 for Existing and Proposed Conditions
HGL Profiles. Please note that the calculations provided with these comments
replaces those as shown in Exhibits 9.1 B and 9.28 of the Manuel Drive Drainage
Report. Sheets 01 and 02 illustrate the existing and proposed conditions of the
storm sewer system along Dartmouth from just upstream of Manuel Drive to the
discharge points at Wolf Pen Creek.
To start the HGL, a free flow condition was assumed at the outfall. This assumption
should be conservative as during a 10-year storm event the water surf ace elevation
in Wolf Pen Creek is well below this outfall elevation. Currently all water on
Dartmouth Drive flows down the street and enters at point "2" as shown on Sheet
01. Under Proposed conditions with the new intersection of Manuel Drive at
Dartmouth the stormwater was required to be picked up in inlets on Dartmouth
upstream of Manuel. This was required per the B/CS Stormwater Design Guidelines
in order to "dry up" the intersection. This requirement now places more than 20
cfs into a pipe that was not designed to accommodate this additional flow. The
stormwater from the Richards Addition and the existing Manuel Drive previously
flowed overland to the open back of the inlet at study point "2 ". With the
extension of Manuel Drive, this flow w il l now enter the pipe upstream of study
point "2".
As a result, as shown on Sheet 02, the pipes upstream of study point "2" now
surcharge when this additional flow is added earlier in the system. This problem
can be alleviated by replacing the section of 24" stormsewer with a 30" pipe
between study points "2b" and "2" as shown on Sheet 03 . As a result of this and
the fact that the existing pipe is an HDPE pipe that was likely embedded in native
fill materials and not structurally embedded in cement stabilized sand, we will
extend the 30" RCP storm sewer to the most upstream 15' inlet. This will allow
the Block 2, Lot 1 development to be designed such that the parking lot and roof
drains can be collected into a private storm system that will discharge into the back
of this upstream 15' inlet. A discussion of this and the effect of not detaining this
development can be found in the Lofts Drainage Study which will be submitted
with the Lofts Construction Plans .
4. COMMENT: Need to show that flow from 100-year storm stays with the ROW for Manuel Drive.
ANSWER: Please see Exhibit 6 of the Manuel Drive Drainage Report for inlet and curb capacity
calculations. The curb calculations indicate that the Q contained in the curb on
each side of Manuel Drive is 24.9 cfs. Therefore if the 100 year flow that enters
each curbline is 24.9 cfs or less then the 100-year storm will stay within the ROW
for Manuel Drive.
Northern Gutter Line
The 100-year flow that enters the northern gutterline of Manuel Drive is that which
contributes from area PA-1.1 as seen in Exhibit 7.2. This flowrate is 7.8 cfs as seen
in Exhibit 8. This flowrate being less than the curb capacity demonstrates that the
100-year flow will stay contained within the curbline.
Southern Gutter Line
The 100-year flow that enters the southern gutterline of Manuel Drive is that which
contributes from area PA-1 .2 as seen on Exhibit 7.2. The 100-year flowrate from
this area is 32.9 cfs as seen in Exhibit 8. As discussed previously, in Exhibit 8 (HGL
calculations) area PA-1 .2 assumed an 85% impervious cover for the Lofts
development on Block 2, Lot 1. The size of this lot is .753 acres. Using a 1 O
minute time of concentration, the 100 year storm event from this lot will produce a
Q100 = 8.3 cfs. Once this flowrate is removed from the flowrate as seen on Exhibit
8 for PA-1 .2 the resultant Q that will enter Manuel Drive is 32 .9 cfs -8.3 cfs = 24.6
cfs, demonstrating that as long as the flow from Block 2, Lot 1 is picked up and
directed subsurface to the inlet on Dartmouth Drive, the 100 year storm will be
sufficiently contained within the curbline of Manuel Drive.
5. COMMENT: Since it appears that the 2411 line is at capacity, you might want to consider the
drainage plan for the Lofts, so if the line needs to be upsized it can be done with
this construction .
ANSWER: We have increased the storm sewer pipe size along Dartmouth from 24 11 to 3011 on
the Manuel Construction Plans. The majority of this size increase is not due to the
Lofts development but rather the extension of Manuel Drive and the requirement
to /1 dry up /1 all legs of an intersection of a collector and arterial street. Any excess
capacity that is created with this increased pipe size will be available to the Lofts
development. Further discussion of the detention analysis for the Lofts and their
needs can be found in the Lofts at Wolf Pen Creek Drainage Report which will be
submitted with the Lofts at Wolf Pen Creek Construction drawings. See discussion
in comment #3.
e let us know if you have any questions or comments.
~ ....... , ... , ,,,, ---"':~~OF 1'~ \\\ .: -<..~ .......... ~ ... ''• ,,: ~_....* ..... -.IS' I ~. ... ... • '1 --------,,, *.... .... *~ (D -5--01' ~'\iERONicA'ji'M'oAGAN~ j!!'····:-···· .. ······ .................... , ~ 1\ 77689 /fl :J 110\-? <;>.··!i;~ 111~··.~~ISTE~~ .. ;ff ;' ''\~s1o°NA\:.·\:.~~-.: ,,,,,,, ............. ~
Cc: Mark Lindley. Asset Plus Corporation, via fax 713.268. 51111
Natalie Ruiz, IPS Group
file
MANUEL DRIVE EXTENSION
THE LOFTS SUBDIVISION
DRAINAGE ANALYSIS
September 2007
Prepared for:
MARK LINDLEY & BARRED KIRK
A SSET PLUS CORPORATION
5151 SAN FELIPE, SUITE 2050
HOUSTON, TX 77056
(713) 268-5122
Submitted to
1/.e heart 0[1/u Reuarch Valley
By
MITCHELL
M M
MORGAN
ENGINEERS & CONSTRUCTORS
511 UNIVERSITY DRIVE, SUITE 204
COLLEGE STATION, TX 77840
OFFICE (979) 260-6963
FAX (979) 260-3564
CERTIFICATION
This report for the drainage design for the Manuel Drive Extension was prepared
under my supervision in accordance with provisions of the Bryan/College Station
Unified Drainage Design Guidelines for the owners of the property. All licenses and
permits required by any and all state and federal regulatory agencies for the
proposed drainage improvements have been issued .
............... , .... ,,,,,
-"":_'\~OF r€ ''' ~~ ... * ............ :t-11S'''t,
~*... ".* ,,,, .... : ............................... . ~VERONICA J.B. MORGAN
?* ..... · ...... ~ 1
~ ..... , ........................... ?(£'
I ~ ""'1 \ 77689 .... 4.Jv
,, ~ "· '9 <> ... ki q ( ~ br 1,1°~ ... ~G1sre.~~ .. -,.ff fl "\'Ss10NA'l. ~~~.:
Veronica J.B. Mor an, P.E ., C.F.M.
Registered Professional Engineer
State of Texas No. 77689
\\,,,,,,,, ........ -
EXECUTIVE SUMMARY
The Manuel Drive extension will be located within Lofts Wolf Pen Creek Subdivision
bisecting Lot 1 Block 1 and Lot 1 Block 2. The extension is approximately 318 LF:
constructed within a 60 foot, 0.454 acre right-of-way (ROW). This property is
currently owned by the Asset Plus Corporation. Preliminary (07-00500153) and Final
(07-00500201) plats have been submitted for this subdivision by Mitchell &
Morgan, LLP; the final plat is currently under City of College Station review and will
be considered by the Planning and Zoning Commission on September 20, 2007.
The current zoning of this property is Wolf Pen Creek (WPC). No zoning change
requests are required for this property as the proposed use is in compliance with
City of College Station zoning regulations. A first round site plan submittal will be
submitted later this month for the Lofts mixed use development to be located on
Lot 1 Block 1 and Lot 1 Block 2 of the Lofts Wolf Pen Creek Subdivision and the
adjacent 6.26 ac Tract 11 . The Manuel Drive Extension construction will only occur
if the Lofts development occurs. Please see Exhibit 1 for the General Location Map.
The development is located south of the intersection of Holleman and Dartmouth
Drive, where Manuel Drive will be extended to Dartmouth Drive. The project site is
located within the lower third of the Wolf Pen Creek Main Drainage Basin, close to
the main channel within Wolf Pen Creek Park. As demonstrated in Exhibit 2, no
portion of the project lies within the regulatory 100-year floodplain per the Federal
Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM) panel
0144C, with an effective date of July 2, 1992. Although the site falls within the
"Evaluate" range in the Detention Requirements by Watershed chart found within
the B/CS United Stormwater guidelines, detention was not considered as part of this
project and will be addressed with the design of the Lofts mixed use development
to be sited on Lot 1 Block 1 and Lot 1 Block 2 of this subdivision as well as the
adjacent 6.26 ac Tract 11.
Existing site conditions consist entirely of grass cover. Stormwater currently flows
overland northwest across the property, towards Dartmouth Drive. A portion of the
existing Manuel Drive and houses on its south side, as well as Lot 1 Block 2 of the
Lofts Wolf Pen Creek Subdivision currently flow through the project site. Please see
Exhibit 3. 1 -Pre-Development Drainage Area Map for existing site conditions and
subbasins . Post-construction will maintain this discharge pattern, collecting drainage
into curb inlets connecting to the existing storm drainage system along Dartmouth
Drive. Please see Exhibit 3.2 -Post Development Drainage Area Map for developed
site conditions and subbasins. Rational Equation calculations for these areas are
provided as Exhibit 4.
Stormwater runoff from Manuel Drive and upland areas will be collected into two
ten foot (1 O') wide curb inlets to be located just before the intersection of Manuel
and Dartmouth Drive. An additional inlet will be located south of the
Manuel/Dartmouth intersection, to keep the intersection clear in storms up to the
25-year event. This inlet will be composed of two fifteen foot (15') inlets separated
by fifteen feet (15'). Twenty-four inch (24") RCP storm sewer will connect the inlets
on Manuel Drive into the existing twenty-four inch (24") RCP storm sewer on the
west side of Dartmouth Drive, as shown in the attached construction plans in
Appendix 8. Pipe sizing calculations are provided in Exhibit 5; Exhibit 6 contains inlet
sizing calculations. Pipes and inlet calculations were performed using the equations
established in the February 2007 B/CS Unified Stormwater Design Guidelines.
Hydraulic grade line (HGL) calculations were done for the existing and proposed
storm sewer system to determine if the existing system had capacity for the
additional subsurface flow designed with the extension of Manuel Drive. Please see
Exhibits 7. 7 and 7.2 for pre-and post-development HGL study areas . Exhibit 8
contains the rational calculations for the HGL study areas. Exhibits 9. 1 A and 9. 18
contain HGL calculations for existing conditions. Exhibits 9.2A and 9.28 contain HGL
calculations for proposed conditions . It was found that the receiving storm sewer
system has adequate capacity for the proposed improvements for the 10-year event.
CONCLUSIONS
The development of the Manuel Drive extension project not will cause a substantial
increase in peak stormwater runoff due to the impervious cover added only with the
street. The effects of the street construction will be reviewed with the development
of the Lofts mixed used development to be located Lot 1 Block 1 and Lot 1 Block 2
of the Lofts Wolf Pen Creek subdivision as well as the adjacent 6.26 ac Tract 11.
The receiving storm sewer system has adequate capacity for the proposed
improvements. Review of the stormwater analysis indicates that the drain age design
presented in this report will provide ample conveyance to meet the drainage
objective of the Bryan/College Station Unified Stormwater Design Guidelines. Please
See Appendix A for the Technical Design Summary.
REFERENCES
1. Bryan/College Station Unified Stormwater Design Guidelines, February
2007.
2. Municipal Development Group, Waterford Apartments Drainage Report.
April 2004 (used for HGL calculations for pond discharge into existing
24" RCP on Dartmouth Drive).
3. Manuel Drive Extension Construction Documents, dated September
2007, Mitchell & Morgan, LLP.
ATTACHMENTS
EXHIBIT 1:
EXHIBIT 2:
EXHIBIT 3.1 :
EXHIBIT 3.2:
EXHIBIT 4:
EXHIBIT 5:
EXHIBIT 6:
EXHIBIT 7.1:
EXHIBIT 7 .2 :
EXHIBIT 8:
EXHIBIT 9.1A:
EXHIBIT 9.1 B:
EXHIBIT 9.2A:
EXHIBIT 9.2B :
APPENDIX A:
APPENDIX B:
APPENDIX C:
General Location Map
Firmette -FEMA Map Panel 0144C
Drainage Plan Map -Existing Condition
Drainage Plan Map -Proposed Condition
Rational Formula Drainage Area Calculations
Pipe Capacity Calculations
Inlet and Curb Capacity Calculations
HGL Existing Conditions Subbasins
HGL Proposed Conditions Subbasins
HGL Rational Formula Drainage Area Calculations
Existing Conditions HGL Calculations -Flow at Study Points
HGL Calculations -Existing Conditions
Proposed Conditions HGL Calculations -Flow at Study Points
HGL Calculations -Propo sed Conditions
Technical Design Summary
Construction Drawings
Excerpt from MDG Waterford Apartments Drainage Report
< 3: w 0
0::: ..J < < 0 u.
w w z I-0
(!) 0::: < z < z < ..J ..J w 0 ~~ < "' w :::!!: ..J ..J z ~ "' > w < 0::: (!) ~ ~ ~ > I-wz 0 < 0 >w 0 I-(!) (!) Q. I-0 ..J
NO. AC. 0.45 0.65 0.95 ft.
EA-1
I
4.01 2.48 1 0.00 1.54 2.57
I
170.0
EA-2 1.02 0.48 0.00 0.54 0.73 154.0
PA-1 .1 0.69 0.16 0.00 0.52 0.57 0.0
PA-1 .2 3.33 1.93 0.00 1.39 2.19 0.0
PA-2 1.02 0.48 0.00 0.54 0.73 154.0
EXHIBIT 4
Rational Formula Drainage Area Calculations
Manuel Drive Extension
3: 0 3: 3: ..J u. 0 0 0 ..J ..J z u. u. ~ < 0::: :c 0::: ..J w I-w 0 (,) (,) I-
0::: ..J I ~ (!) ~ ..J 0 I-w ..J ..J .!:! w :::> z :::> ..J >< (!) ~ (!) ~ w ftl "' N 0 u. > 0 :::> ~ a ~
ft. ft. ft. ft/• min min In/Hr cfs In/Hr
6.0 715.0 17.3 2.5 6.0 10.0 1 6.33 16.3 I 7.7
1.7 607.0 21 .5 2.0 6.2 10.0 6.33 4.6 7.7
0.0 1003.0 24.6 3.1 5.4 10.0 6.33 3.6 7.7
0.0 964.0 23.4 3.1 5.2 10.0 6.33 13.9 7.7
1.7 607.0 21 .5 2.0 6.2 10.0 6.33 4.6 7.7
I
I
I
I
I 0 0 It) 0 0 0 ~ I ~ .... It) N 0 It) 0 I .... a N a It) a .... a
cfs lnlHr I cfs 1 lnlHr I cfs I 1nlHr I cfs In/Hr cfs
119.8 8.6 22.2 9.9 25.4 11 .1 I 28.7 12.5 32.3
5.6 8.6 6.3 9.9 7.2 11 .1 8.1 12.5 9.1
4.4 8.6 4.9 9.9 I 5.6 I 11 .1 6.4 12.5 7.2
16.9 8.6 18.9 9.9 21 .6 11 .1 24.4 12.5 27.5
5.6 8.6 6.3 9.9 I 7.2 11 .1 8.1 12.5 9.1
9/16/2007
CVUIOIT A
!:2 m ...... x CJ) ::::; ---· N 0-0 ;::::;: 0 tn --.J -01 "U =!> =!> ............ N_. "U (._ )> ' ' 0-...... 0 :......x NN i-.Ji:::o ............ 00 Q....>. ............ 00 _.N co(,.) coco NN ~I~ --.J--.J ............ NN (,.)co --.J --.J N v.> ON coco I N v.> ...... (,.) 00 ~ NN """""" --.J co °' c.n --NN (,.)co :...... i:::o -(,.) """ """ ...... -00 00 co --.J -............ 00 Q....>. co tn :u: INLET NO. :u: TO INLET ~TOTALCA ~.Tc ~ Design Storm ,., Unadjusted .... . "' Design Flow ,., Adjusted .... . "' Design Flow :u: No. of Pipes a. Flow Per Pipe "t. Friction Slope --~ "t. Pipe Slope -=SIZE i' VEL. ---a. Capacity -·LENGTH -~· Travel Time ---~· Tc@End ""C s:: -0' II) (I) ::I ("') c: II) ~ 'O m c ~ >< ~ -· ::I: :c:·~ a; (I) ("') -m o.i -i )( -(11 ... 0 (I) c: ::I -"' ~ c;· c;· ::I ::I "'
INLET AND CURB CAPACITY
Q=3.0*l*yA1 .5
L=Q/(3.0*yA1 .5)
ON-GRADE (recessed)
PA-1.1
Q= 4.9 cfs
s= 0.02325
n= 0.018
Sx= 0.03
W= 3.5 ft
T= 16.66 ft
a= 0.333 ft
SUMP (recessed)
PA-1.2
Q= 18.90 cfs
y = 0.83 ft
L=I a.2alft
ON-GRADE (recessed)
PA-2
Q= 7.25 cfs
s= 0.0517
n= 0.018
Sx= 0.03
W= 3.5 ft
T= 16.66 ft
a= 0.333 ft
Note*
Recessed inlets curb opening =
Height of curb +depression
y = 6"+4"=equal 1 O"
Lx=Kc*(QA .42)*(SA .3)*( 1 /(n*Se) )A .6
Se=Sx+(a/W)*(EO))
EO=(Qw/Q)=1-(1 -WJT)A2 .67
(10 year storm)
E0=1 0.4671
Se= 0.074
Lx=I 20.03lft
(10 Year Storm)
(25 Year Storm)
E0=1 0.4671
Se= 0.074
Lx=I 30.01 lft
CURB CAPACITY (Straight Crowns)
PA-1.1 & 1.2
(depth) Y=
Q=0.56 (z/n)sA0.5*YA2.67
z= 33.33
s= 0.023
Y= 0.5
n= 0.018
a=I 24.9 lets
Exhibit 6
< ;:
w 0 rx: ...J < ;5 0 u.
w z I-0
(!) rx: ~ z < z
< < ...J w 0 ~ :r: z ...J U) w ::E ...J rx: I-~ U) > w < ~ C2 C2 > I-w (!) >z 0 < 0 o~ 0 I-(!) (!) a.. I-
NO. AC. 0.45 0.65 0.95 ft.
EA-1 I ·~ 2.48 0.00 1.54 2.57 170.0 --~ -f---
EA-2 1.02 0.48 0.00 0.54 0.73 154.0 --- -
EA-3 3.19 2.20 0.00 0.99 1.93 0.0 --EA-5 0.58 0.00 0.00 0.58 0.55 0.0
PA-1.1 0.69 0.07 0.00 0.62 0.62 0.0
PA-1 .2 3.32 1 06 0.00 2.27 2.63 0.0 --
PA-2 1.02 0.48 0.00 0 5_£ 0.73 154.0 "' ---
PA-3 I 1.83 0.84 0.00 0.99 1.32 154.0 ---
PA-5 0.58 0.00 0.00 0.58 0.55 154.0
EXHIBIT 8
Rational Formula Drainage Area Calculations
Manuel Drive Extension -HGL Areas
;:
0 ;: ;: ...J u. 0 0 0 ...J ...J z u. u. ~ ~ rx: :r: rx: 0 " w I-w I-" rx: ...J ~(!) ~ ...J 0 I-w ...J ...J " w :::> z :::> ...J ;; >< (!)~ (!) ~ w U) N 0 u. > 0 :::> !:'.'.! 0 !!?
ft. ft. ft. ft/s min min In/Hr cfs In/Hr
6.0 715~1 17.3 2.5 6.0 10.0 6.33 16.3 7.7
1.7 607.0 21 .5 2.0 6.2 10.0 6.33 4.6 7.7 -0.0 1003.0 24.6 3.1 5.4 10.0 6.33 12.2 7.7
0.0 964.0 23.4 3.1 5.2 10.0 6.33 3.5 7.7
0.0 1003.0 24.6 3.1 5.4 10.0 6.33 3.9 7.7
0.0 964.0 23.4 3.1 5.2 ~10.0 6.33 16.6 7.7
1.7 607.0 21 .5 2.0 6.2 10.0 6.33 4.6 7.7 --
1.7 607.0 21 .5 2.0 6.2 10.0 6.33 8.3 7.7 -1.7 607.0 21 .5 2.0 6.2 10.0 6.33 3.5 7.7
0 0 in 0 0 0 It) 0 .... It) N 0 in 0 .... 0 :!: 0 !:'.'.! 0 !!? 0 :!: 0
cfs In/Hr cfs In/Hr cfs In/Hr cfs In/Hr cfs
19·1 8.6 22.2 9.9 25.4 11 .1 28.7 12.5 32.3 I-'--. ---5.6 8.6 6.3 9.9 7.2 11 .1 8.1 12.5 9.1 --14.9 8.6 16.7 9.9 19.0 11.1 21 .5 12.5 24.2
4.3 8.6 4.8 9.9 5.5 11 .1 6.2 12.5 6.9
4.8 8.6 ~I 9.9 j 6.1 11 .1 I 6.9 J 12.5 I 7.8
20.2 8.6 7 9.9 25.9 11.1 29.3 1 12.5 1 32.9
31 5.6 8.6 9.9 7.2 11.1 8.1 12.5 9.1
10.1 8.6 ~ 9.9 13.0 11.1 14.7 1 12.5 , 16.5
4.3 8.6 8 9.9 5.5 11.1 6.2 12.5 6.9
9/16/2007
CVWIC IT o
EXHIBIT 9.1A
HGL CALCULATIONS -EXISTING CONDITIONS
FLOW AT STUDY POINTS
Basin Inc. Flow (cfs) Study Pts Q Cum. (cfs)
EA-1 22.2 1 64.56
EA-2 6.3 2 59.76
EA-3 16.7 3 14.56
EA-4 14.6
EA-5 4.8
EXHIBIT 9.1A
:E' ...... ...... .::: ..... :E. "' c: ..... E 0 E IQ a. E ·;; IQ QI 0 IQ ... v QI .... QI .... QI ... "' ...
c: .... c: J: t: c: "' := :1! c: Q, 0 :::> 0 := u 0 0 -' u.. -' 0 u..
2 to 1 267 .6 266.0 271.8
2b to 2 270.8 268.7 277.6
3 to 2b 282 .8 270.8 287.8
EXHIBIT 9.18
HGL CALCULATIONS -EXISTING CONDITIONS
MANUEL DRIVE EXTENSION
...... "' ...... 't :E. ...... ...... ..... "' :E' ...... .::: c: := ~ .::: ;,::;. -g' ';;;' .... ..... -0 Q, .::: ...
QI u::: QI ~ ..... ·-"' .... c: 0 .... 0 O'I QI QI E c: -c: Q, E IQ IQ "'C "'iij QI 0 IQ QI :1! ~ E -' Vi c ... .... J: ...
"' 0 Q, z :::>
76 .29 0.0210 30 59.76 1.6 1 2.06
198.19 0.0106 24 14.56 0.82 1.15
205.01 0.0585 24 14.56 0.84 0.70
-"' -' O'I "'iij \!I c: J: E~ ...... ·-E ...... "' c: ... .::: E IQ :=. Q,
c: QI QI -0 ..... ..... IQ ...... IQ ...... ... v z~ t: c: >. :1! :E. ~.::: >. .... ....
..c g. .... ..... c: IQ ·v >. "' := ... 0 ..c -' 0 c: IQ
\!I := 0 QI Qi -' Ou > \!I J: 0
J: 0
268.50 269.66 269.66 2.14 13.82
270.48 271 .95 271 .95 5.65 7.80
272 .79 283.50 283 .50 4.30 14.75
EXHIBIT 9.18
EXHIBIT 9.2A
HGL CALCULATIONS -PROPOSED CONDITIONS
FLOW AT STUDY POINTS
Basin Inc. Flow (cfs) Study Pts Q Cum. (cfs)
PA-1-1 5.4 1 65.16
PA-1-2 22.7 2 60.36
PA-2 6.3 3 48.96
PA-3 11.4 4 28.1
PA-4 14.6 5 22.7
PA-5 4.8 6 20.9
7 14.6
EXHIBIT 9.2A
g E E "' VI "' 41 c: 41 ... 0 E ... ....
"€ .... VI "' VI ..-. c. ..-. 41 41 c: .;: ::::> .;: ... c: .... ~ ....... c. ....... VI c: c. 0 0 0 ::::> 0 I-u ...J ...J ::c u.. u.. ~
2 to 1 266.0 264.0 271 .8
3 to 2 272.32 267.60 278.88
6 to 3 278.08 272.42 283 .54
7 to 6 282.20 278.08 287.80
4 to 3 274.02 272.96 280.22
5 to 4 275.00 274.12 280.88
EXHIBIT 9.28
HGL CALCULATIONS -PROPOSED CONDITIONS
MANUEL DRIVE EXTENSION
E .VI
~ en ~ VI E ....... c: E 0 g ~ .... u::: "gi '; .... c: .;: ... c. c: 41 E~ 41 "' ..-. ~ ....... ·c: lS .... .... "' .... 0 ~:E. 41 41 en 41 ~ c: -c: c. E "' "C iii 0 ... >-41 "' .... ~ :3 E .&l ...J iii 0 VI c. ::c ... ...J ::::> 0 I.!> z ::c
76.29 0.0262 30 60.36 1.64 1.87 264.00
226.70 0.0208 24 48.96 10.56 2.00 278.43
95.82 0.0591 24 22 .70 0.96 0.89 279.39
84.05 0.0490 24 28.10 1.29 1.07 280.68
32 08 0.0330 24 20.86 0.27 1.01 279.39
42.07 0.0210 24 14.56 0.17 0.93 279.56
g iii
Eg ~ E ..-. ...J c. ... .;: I.!> .... 0 ....... ::c "' 41 ....... z~ 41 v >-E ... c: >-.... .... "' .... ·;:::; .&l c. "' VI ._ 41 41 c. "' 0 ~o ... ::::> 41 Qi .... VI iJ > ::c c. ::::>
267.87 267.87 3.93 15.32
274.32 278.43 0.45 15.58
278.97 279.39 4.15 7.23
283.27 283.27 4.53 8.94
278.97 279.39 0.83 6.64
275.93 279.56 1.32 4.63
EXHIBIT 9.28
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 2 -Project Administration I Start (Page 2.1)
Engineering and Design Professionals Information
Engineering Firm Name and Address: Jurisdiction
Mitchell & Morgan, L.L.P. City: 0 Bryan
511 University Dr., Suite 204 0 College Station College Station, TX 77845
Date of Submittal: 911712007
Lead Engineer's Name and Contact lnfo.(phone, e-mail, fax): Other:
Veronica Morgan --p (979)260-6963, f(979)260-3564, v@mitchellandmorgan.com NIA
Supporting Engineering I Consulting Firm(s): Other contacts:
NIA NIA
Developer I Owner I Applicant Information
Developer I Applicant Name and Address: Phone and e-mail:
Asset Plus Corporation, clo Mark Lindley and Barrett Kirk (713)268-5122
5151 San Felipe, Suite 2050 mlindley@assetpluscorp.com
Houston, TX 77056 D
Property Owner(s) if not Developer I Applicant (&address): Phone and e-mail:
same as above
Project Identification
Development Name: Manuel Drive Extension
Is subject property a site project, a single-phase subdivision, or part of a multi-phase subdivision?
single-phase subdivision If multi-phase, subject property is phase of
Legal description of subject property (phase) or Project Area:
(see Section 11, Paragraph B-3a)
Extension of Manuel Drive
If subject property (phase) is second or later phase of a project, describe general status of all
earlier phases. For most recent earlier phase Include submittal and review dates.
NIA
General Location of Project Area, or subject property (phase):
Extension of existing Manuel Drive to Dartmouth Drive near intersection with Holleman Drive
In City Limits? Extraterritorial Jurisdiction (acreage):
Bryan: NIA acres. Bryan: NIA College Station: NIA
College Station: 0.454 acres. Acreage Outside ET J: NIA
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 3 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
APPENDIX A
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 2-Project Administration I Continued (page 2.2)
Project Identification (continued)
Roadways abutting or within Project Area or Abutting tracts, platted land, or built
subject property: developments:
Manuel Drive Lot I, Block I & Lot I, Block 2
Dartmouth Drive The Lofts -Wolf Pen Creek
Holleman Drive
Named Regulatory Watercourse(s) & Watershed(s): Tributary Basin(s):
Wolf Pen Creek NIA
Plat Information For Project or Subject Property (or Phase)
Preliminary Plat File#: 07-oo5ooi 53 Final Plat File#: 07-00500201 Date: 8120107
Name: The Lofts -Wolf Pen Creek Status and Vol/Pg: Scheduled for P&Z 9120
If two plats, second name: Woodstock Section I File#: 170832
Status: Files Date: l 0117179
Zoning Information For Project or Subject Property (or Phase)
Zoning Type: Wolf Pen Creek Existing or Proposed? Existing Case Code: 06-00500279
Case Date 12115106 Status: Existing
Zoning Type: NIA Existing or Proposed? Existing Case Code: NIA
Case Date NIA Status: NIA
Stormwater Management Planning For Project or Subject Property (or Phase)
Planning Conference(s) & Date(s): Participants:
NIA NIA
Preliminary Report Required? No Submittal Date NIA Review Date NIA
Review Comments Addressed? Yes t . J No L J In Writing? No When?
Compliance With Preliminary Drainage Report. Briefly describe (or attach documentation
explaining) any deviation(s) from provisions of Preliminary Drainage Report, if any.
NIA
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 4 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 2 -Project Administration I Continued (page 2.3)
Coordination For Project or Subject Property (or Phase)
Note: For any Coordination of stormwater matters indicated below, attach documentation
describing and substantiating any agreements, understandings, contracts, or approvals.
Coordination Dept. Contact: Date: Subiect:
With Other Electrical Gilbert Martinez 8120--915 Easements agreed upon
Departments of NIA NIA NIA NIA Jurisdiction
City (Bryan or NIA NIA NIA NIA
College Station) NIA NIA NIA NIA
Coordination With Summarize need(s) & actions taken (include contacts & dates):
Non-jurisdiction NIA
City Needed?
Yes .D._No ..D_
Coordination with Summarize need(s) & actions taken (include contacts & dates):
Brazos County NIA
Needed?
Yes .CJ.. No [ZJ
Coordination with Summarize need(s) & actions taken (include contacts & dates):
TxDOT Needed? NIA
Yes .D_No D
Coordination with Summarize need(s) & actions taken (include contacts & dates):
T AMUS Needed? NIA
Yes.DNo CJ
Permits For Project or Subject Property (or Phase)
As to stormwater management, are permits required for the proposed work from any of the entities
listed below? If so, summarize status of efforts toward that objective in spaces below.
Entity Permitted or
Approved?
US Army Crops of
Engineers NIA
No ..cz:L Yes D
US Environmental
Protection Agency
DD No Yes __ ; NIA
Texas Commission on
Environmental Quality
No fil_ Yes L __ J NIA
Brazos River
Authority
No .l:Il._ Yes D NIA
STORMWATER DESIGN GUIDELINES
Effective February 2007
Status of Actions (include dates)
NIA
NIA
NIA
NIA
Page 5 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 3 -Pro~ertv Characteristics I Start (Page 3.1)
Nature and Scope of Proposed Work
Existing: Land proposed for development currently used, including extent of impervious cover?
vacant, 0% impervious
Site L .... 'I Redevelopment of one platted lot, or two or more adjoining platted lots.
Development D Building on a single platted lot of undeveloped land.
Project L . I Building on two or more platted adjoining lots of undeveloped land.
(select all I ... J Building on a single lot, or adjoining lots, where proposed plat will not form applicable) a new street (but may include ROW dedication to existing streets).
l ..... j Other (explain):
Subdivision L . I Construction of streets and utilities to serve one or more platted lots.
Development L:.J Construction of streets and utilities to serve one or more proposed lots on Project lands represented by pending plats.
Site projects: building use(s), approximate floor space, impervious cover ratio .
Describe Subdivisions: number of lots by general type of use, linear feet of streets and
Nature and drainage easements or ROW.
Size of 318.4 LF of street (Manuel Dr. extension)
Pro12osed
Project
Is any work planned on land that is not platted If yes, explain:
or on land for which platting is not pending? NIA
I_" :I No L_J Yes
FEMA Floodplains
Is any part of subject property abutting a Named Regulatory Watercourse I No J:Z1 Yes _.D_ (Section 11 , Paragraph B 1) or a tributary thereof?
Is any part of subject property in floodplain I No CJ Yes 1 --~ Rate Map area of a FEMA-regulated watercourse?
Encroachment(s) Encroachment purpose(s): I .... l Building site(s) l I Road crossing(s) into Floodplain
areas planned? D Utility crossing(s) I .. I Other (explain):
No m_ NIA
Yes l l
If floodplain areas not shown on Rate Maps, has work been done toward amending the FEMA-
approved Flood Study to define allowable encroachments in proposed areas? Explain.
NIA
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 6 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 3 -Pro~ert~ Characteristics I Continued (Page 3.2)
Hydrologic Attributes of Subject Property (or Phase)
Has an earlier hydrologic analysis been done for larger area including subject property?
Yes Reference the study (& date) here, and attach copy if not already in City files.
.J:Zl Wolf Pen Creek Flood Study, October 2006 Letter of Map Revision (contained in City files)
Is the stormwater manr:er ent plan for the property in substantial conformance with the
earlier study? Yes .. , No CZJ If not, explain how it differs.
The extension of Manuel Drive will cause an increase of approximately 0.382 acres of impervious cover.
Manuel Drive will only be constructed if Lot I, Block I & Lot I, Block 2 of The Lofts -Wolf Pen Creek
Subdivision are developed. A timing analysis will be completed with the design of The Lofts subdivision to
determine if detention is needed.
No If subject property is not part of multi-phase project, describe stormwater management
0 plan for the property in Part 4.
If property is part of multi-phase project, provide overview of stormwater management plan
for Project Area here. In Part 4 describe how plan for subject property will comply
therewith.
NIA
Do existing topographic features on subject property store or detain runoff? J:Z:J__ No ....c::J... Yes
Describe them (include approximate size, volume, outfall, model, etc).
NIA
Any known drainage or flooding problems in areas near subject property? J:Z:J__ No J:::L Yes
Identify:
NIA
Based on location of study property in a watershed, is Type 1 Detention (flood control) needed?
(see Table B-1 in Appendix B)
l::=J Detention is required. t ; J Need must be evaluated. I . J Detention not required.
What decision has been reached? By whom?
We will investigate detention requirements with the development of Lots I Block I & Lot 1
If the need for Block 2 of the Lofts Subdivision. Manuel won't be constructed unless these blocks develoo. GI
Type 1 Detention How was determination made?
must be evaluated: Not yet made.
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 7 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ____ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 3 -ProQertv Characteristics I Continued (Page 3.3)
Hydrologic Attributes of Subject Property (or Phase) (continued)
Does subject property straddle a Watershed or Basin divide? J::lNo I rnJ Yes If yes ,
describe splits below. In Part 4 describe design concept for handling this.
Watershed or Basin Larger acreage Lesser acreage
Above-Project Areas(Section II, Paragraph 83-a)
Does Project Area (project or phase) receive runoff from upland areas? D.. No .r:::J Yes
Size(s) of area(s) in acres: 1) 3.132 ac 2) 3) 4)
Flow Characteristics (each instance) (overland sheet, shallow concentrated, recognizable
concentrated section(s), small creek (non-regulatory), regulatory Watercourse or tributary);
shallow concentrated flow from existing Manuel drive, overland flow from houses on east side on Manuel and Lot
I Block 2 of the Lofts subdivision by sheet flow
Flow determination: Outline hydrologic methods and assumptions:
Rational method, Cgrass=0.45, Cpavement=0.95, time of concentration and intensity calculated using methods
outlined in B/CS stormwater guidelines
Does storm runoff drain from public easements or ROW onto or across subject property?
I J No L; J Yes If yes, describe facilities in easement or ROW:
existing Manuel Drive ROW, 8 in waterline on west side of existing Manuel drive, terminated at subject property
(Manuel Drive extension). There is no storm sewer in Manuel Drive.
Are chanqes in runoff characteristics subject to chanqe in future? Explain
No, because Manuel Drive will only be constructed if Block 1 Lot I and Block 2 Lot I of the Lofts Subdivision is
developed. Above project areas are already fully constructed.
Conveyance Pathways (Section II , Paragraph C2)
Must runoff from study propertf,drat across lo.er r operties before reaching a Regulatory
Watercourse or tributary? -~--No '-' Yes
Describe length and characteristics of each conveyance pathway(s). Include ownership of
property(ies).
Dartmouth Drive ROW/storm sewer, owned by the City of College Station -storm water will enter I of2 proposed
inlets on the extension of Manuel Drive near the intersection of Manuel and Dartmouth Drive. A 24" RCP (34 LF)
pipe will constructed between the 2 new inlets, discharging water from these inlets to a new 24" RCP ( 41 LF) to
enter the existing 24" RCP on Dartmouth through a junction box. A new inlet will be constructed on the existing
24" storm sewer on the south side of Dartmouth, east of the Dartmouth/Manuel intersection. Storm water from the
project area will continue northwest in the existing 24" RCP (227 LF) then go northwest under Dartmouth through
30" RCP (71 LF) discharging into WolfPen Creek Main. D
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 8 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ____ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 3 -Pro~ert~ Characteristics I Continued (Page 3.4)
Hydrologic Attributes of Subject Property (or Phase) (continued)
Conveyance Pathways (continued)
Do drainage If yes, for what part of length? 100 % Created by? I ' I plat, or
easements I _) instrument. If instrument(s), describe their provisions. exist for any
part of City construction of Dartmouth Drive - Dartmouth Drive stormsewer
pathway(s)?
L I No
I / 11 Yes
Where runoff must cross lower properties, describe characteristics of abutting lower
property(ies). (Existing watercourses? Easement or Consent aquired?)
Dartmouth Drive ROW Pathway
Areas
Describe any built or improved drainage facilities existing near the property (culverts,
bridges, lined channels, bu ried conduit, swales, detention ponds, etc).
24" storm sewer along south side of Dartmouth drive, 30" storm sewer under Dartmouth discharging to
Wolf Pen Creek Main
Nearby
Drainage Do ~ny? of these have r ydrl'ogic or hydraulic inf!uence on proposed stormwater Facilities design. I _ _j No L _ Yes If yes, explain:
See attached HGL calculations
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 9 of 26 APPENDIX. D: TECH. DESIGN SU MMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Start (Page 4.1)
Stormwater Management Concept
Discharge(s) From Upland Area(s)
If runoff is to be received from upland areas, what design drainage features will be used to
accommodate it and insure it is not blocked by future development? Describe for each area,
flow section, or discharge point.
The Lofts subdivision is the last portion of upland area that discharges across the site that is undeveloped. The
extension of Manuel Drive is a part of the Lofts development, but has been submitted to the City of College Station
as a separate plan set. Manuel Drive will not be constructed ifthe Lofts does not develop. Drainage from the Lofts
will not be blocked by the extension of Manuel Drive. Runoff from the development of Lot I Block 2 will discharge
into the storm sewer infrastructure constructed with the construction of Manuel Drive. Areas already developed will
discharge to the ROW of the extension of Manuel Drive, entering the proposed storm sewer.
Discharge(s) To Lower Property(ies) (Section II , Paragraph E1)
Does project include drai[;Zje features (existing or future) proposed to become public via
platting? L JI No ~Yes Separate Instrument? CJ No Cl Yes
Per Guidelines reference above, how will I . A Establishing Easements (Scenario 1) runoff be discharged to neighboring
property(ies)? j_;_j Pre-development Release (Scenario 2)
c::J Combination of the two Scenarios
Scenario 1: If easements are proposed, describe where needed, and provide status of actions
on each . (Attached Exhibit # )
NIA
Scenario 2: Provide general description of how release(s) will be managed to pre-development
conditions (detention, sheet flow, partially concentrated, etc.). (Attached Exhibit# )
Manuel Drive extension will only be constructed if Block 1Lot1 and Block 2 Lot I of the Lofts subdivision
develop. Detention for the street, if necessary, will be taken care of with the detention of the Lofts development. This
drainage report will be submitted with the Lofts construction documents.
Combination: If combination is proposed, explain how discharge will differ from pre-
development conditions at the property line for each area (or point) of release.
NIA
If Scenario 2, or Combination are to be used, has prj poj ed design been coordinated with
owner(s) of receiving property(ies)? CZJ No --: Yes Explain and provide
documentation.
Detention requirements for the Lofts development will be determined with the Lofts construction documents. The
City of College Station is the owner of all receiving properties and will review the drainage documents for this
development.
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 10 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ____ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.2)
Stormwater Management Concept {continued)
Within Project Area Of Multi-Phase Project
Identify gaining Basins or Watersheds and acres shifting:
Will project result
in shifting runoff NIA
between Basins or
between What design and mitigation is used to compensate for increased runoff
Watersheds? from gaining basin or watershed?
l ' I No NIA
t .J Yes
How will runoff from Project 1. I 'J With facility(ies) involving other development projects.
Area be mitigated to pre-2. I -] Establishing features to serve overall Project Area. development conditions?
Select any or all of 1, 2, 3. I I On phase (or site) project basis within Project Area.
and/or 3, and explain below.
1. Shared facility (type & location of facility; design drainage area served; relationship to size of
Project Area): (Attached Exhibit# )
Detention requirements for the Lofts development and Manuel Drive will be determined with the Lofts construction
documents. The size of this facility has not yet been determined. Manuel Drive will not be constructed if the Lofts
project is not developed. The entire Lofts project, including Manuel Drive, totals 2.426 acres.
2. For Overall Project Area (type & location of facilities): (Attached Exhibit# )
NIA
3. By phase (or site) project: Describe planned mitigation measures for phases (or sites) in
subsequent questions of this Part.
Are aquatic echosystems proposed? CZJ No Cil Yes In which phase(s) or
project(s)?
C'·
"'C Q) VI c Q) c >-Are other Best Management Practices for reducing stormwater pollutants proposed? re ~EJ CJ No Cl Yes Summarize type of BMP and extent of use:
c NIA Cl 'iii
Q) o~
fol If design of any runoff-handling facilities deviate from provisions of B-CS Technical
Specifications, check type facility(ies) and explain in later questions.
Q) CJ Detention elements CJ Conduit elements D Channel features
~ CJ Swales L I Ditches LLJ Inlets L i Valley gutters I J Outfalls
D Culvert features D Bridges Other
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 11 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage ConceQt and Design Parameters I Continued (Page 4.3)
Stormwater Management Concept (continued)
Within Project Area Of Multi-Phase Project (continued)
Will Project Area include bridge(s) or culvert(s)? I / I No I ,J Yes Identify type and
general size and In which phase(s).
NIA
If detention/retention serves (will serve) overall Project Area, describe how it relates to subject
phase or site project (physical location, conveyance pathway(s), construction sequence):
NIA
Within Or Serving Subject Property (Phase, or Site)
If property part of larger Project Area, is dj si:f in substantial conformance with earlier analysis
and report for larger area? D Yes . No, then summarize the difference(s):
NIA
Identify whether each of the types of drainage features listed below are included, extent of use,
and general characteristics.
Typical shape? I Surfaces?
C'-·
-0 <IJ (/) Steepest side slopes: Usual front slopes: I Usual back slopes: (/)
::I <IJ (/) >-i DI Flow line slopes: least Typical distance from travelway:
typical greatest (Attached Exhibit # )
<IJ -0 0 ·u; z
1 Bl Are longitudinal culvert ends in compliance with 8-CS Standard Specifications?
L.. D Yes c::J No, then explain: <{
(/) At intersections or otherwise, do valley gutters cross arterial or collector streets?
..0 <IJ rz:'I No L J Yes If yes explain: :; ('-· >-
u -0 I ~~El :;:: ..... Are valley gutters proposed to cross any street away from an intersection? (/) <IJ -:i:: L 1 ] No I J Yes <IJ ::I 0 Explain: (number of locations?) ~ OlZ ]~01
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 12 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.4)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
Gutter line slopes: Least 0.8% Usual 2.3% Greatest 2.3%
Are inlets recessed on arterial and collector streets? Id Yes I -J No If "no",
identify where and why.
Will inlets capture 10-year dj si:f stormflow to prevent flooding of intersections (arterial
with arterial or collector)? -·-· '-· Yes I . I No If no , explain where and why not.
('-·
"O G.> VI Will inlet size and placement prevent exceet ng/llowable water spread for 10-year ::J .._ design storm throughout site (or phase)? ~Yes I ___ J No If no, explain . G.> :t:: ::J Cl
-o-c "O ro a.> Sag curves: Are inlets placed at low points? I . Ji Yes u 11 No Are inlets and ..c ~ .._ ·-conduit sized t:5event 100-year stormflow from ponding at greater than 24 inches? ::J ...... u c I 'J Yes __ . No Explain "no" answers. 0 .I::. u ~ ........... ~ I inlet is in a sag, the other is placed at grade because the street had to match the existing grade on the
VI cross street (Dartmouth Drive) Q)
G.> .._
Ui
G.> Will 100-yr stormflow be contained in combination of ROW and buried conduit on .._
<{ whole length of all streets? L!.J Yes c=J No If no, describe where and why.
Do designs for curb, gutter, and inlets comply with 8-CS Technical Specifications?
D Yes I 'i No If not, describe difference(s) and attach justification.
See note modification made to the B/CS Drainage Sheet in Plan set. Because of the placement of the
existing storm sewer along Dartmouth the "retrofitted" inlets may be required to be deeper than normal
Are any 12-inch laterals used? I ' 1 No I I Yes Identify length(s) and where
used.
C'-· "O Pipe runs between system I Typical 37.5 LF G.> VI Longest 41 LF
VI G.> access points (feet): ::J >-E [Zj CJ ~GI Are junction boxes used at each bend? --Yes No If not, explain where
and why.
VI
c ·-0 ~z iol Are downstream soffits at or below upstream soffits? Least amount that hydraulic VI
.!!!. Yes L 1 A No I '.I If not, explain where and why: grade line is below gutter line
(system-wide):
0.45 LF -Refer to HGL calculations
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 13 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ____ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.5)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
(i)
Describe watercourse(s), or system(s) receiving system discharge(s) below
Q) (include design discharge velocity, and angle between converging flow lines).
u c 1) Watercourse (or system), velocity, and angle? ro iii c 24" stormsewer, Dartmouth Dr., 6.64 fps, 113 degrees
Q) ..... ~a ~E 2) Watercourse (or system), velocity, and angle? ::I ..... c 0 NIA ·--c . oE ~.!:
E <ll ~ <ll E 3) Watercourse (or system), velocity, and angle? ..... ro Cii ~ Ul t
Ul Q) ::I NIA
c:!2 0 ·-> ~ e "O a.
E ..... For each outfall above, what measures are taken to prevent erosion or scour of ..... Q) 0 Q) receiving and all facilities at juncture? ..... ..c
(/) Ul
2 1) Velocity kept below 12 fps at this point ~ ro a. 2) Q) Ul
c 3) .s
Are swale(s) situated along property lines between properties? I ; I No I .. I Yes
Number of instances: For each instance answer the following questions.
Surface treatments (includinQ low-flow flumes if any):
NIA
C'-· Ul Qi ~ Ul ..... Q) Flow line slopes (minimum and maximum): Ul >-
!01 NIA
~o
Ul z ::I Outfall characteristics for each (velocity, convergent angle, & end treatment).
~GI NIA
Ul
Q) ..... Will 100-year design storm runoff be contained within easement(s) or platted drainage <(
ROW in all instances? D Yes Di No If "no" explain:
NIA
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 14 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.6)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
Are roadside ditches used? r::z:ll No I .JI Yes If so, provide the following:
I/) Is 25-year flow contained with 6 inches of freeboard throughout? I. • Yes l .. I No a.> ..c .B Are top of banks separated from road shoulders 2 feet or more? I U Yes L A No
0 Are all ditch sections trapezoidal and at least 1.5 feet deep? L I Yes L .l No a.> :!::! For any "no" answers provide location(s) and explain: I/) "C ('IJ NIA a a::::
If conduit is beneath a swale, provide the following information (each instance).
Instance 1 Describe general location, approximate length:
I/) n/a a.> >-
Dlw Is 100-year design flow contained in conduiUswale combination? I J Yes c::1 No
If "no" explain: n/a
c:: a ('IJ
Space for 100-year storm flow? ROW c::J Easement r:=::I z iii Width Bl~ Swale Surface type, minimum Conduit Type and size, minimum and maximum
a and maximum slopes: slopes, design storm:
C'· E n/a n/a "C I/) "C a; ('IJ c:: >-Inlets Describe how conduit is loaded (from streets/storm drains, inlets by type): c:: ('IJ c::
..c ('IJ n/a u ....
c:: .!2
a.> c:: a. a 0 :.;:::; Access Describe how maintenance access is provided (to swale, into conduit): -('IJ a § :::J n/a .!!:! .!2 c:: c:: a.>
"C E Instance 2 Describe general location, approximate length: a.> ('IJ I/) I/) :::J n/a
I/) a.>
c:: "C a ·;:; Is 100-year design flow contained in conduiUswale combination? L JYes l 1 No ~ a .... If "no" explain: n/a c:: a. :.a Q)
E a.>
ROW c::J Easement l::=I a ..c Space for 100-year storm flow? Width u I/) ...... a.> Swale Surface type, minimum Conduit Type and size, minimum and maximum :::J -ro "C .... and maximum slopes: slopes, design storm: c:: ('IJ a 0..
.!::? a.>
a.> I/) Inlets Describe how conduit is loaded (from streets/storm drains, inlets by type): ro c::
3: _£.
n/a I/)
a.> .... <( Access Describe how maintenance access is provided (to swale, into conduit):
n/a
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 15 of26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4-Drainage Concept and Design Parameters I Continued (Page 4. 7)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
.5 ro a.
If "yes" provide the following information for each instance:
Instance 1 Describe general location, approximate length, surfacing:
NIA
E x 0 w ~ :g ui Is 100-year design flow contained in swale? I . I Yes !. Ji No Is swale wholly
c ~ within drainage ROW? r::::::ll Yes D No Explain "no" answers: .;IJI t--N-1A _____________________________ --1
u Access Describe how maintenance access is provide: ~ o NIA 1 D1 t--ln-s-ta_n_c_e_2 __ D_e_sc-r-ib_e_g_e_n_e-ra-l-lo_c_a_ti_on-.-a-p-p-ro-x-im-a-te_l_e-ng_t_h_, s_u_rf_a_c-in_g_: -----~
Q) ·;:: r-· NIA ::::J IJ)
.0 c
:; Q)
o E £ Q) .§ gi
Q)
IJ) '-
Q) 0 ~ s:
IJ) 0
0::: ~ .!::! ::0 ::::J a.
Is 100-year design flow contained in swale? I I Yes CJ No Is swale wholly
within drainage ROW? CJ Yes D No Explain "no" answers:
NIA
Access Describe how maintenance access is provided:
NIA
Instance 3, 4, etc. If swales are used in more than two instances, attach sheet
providing all above information for each instance.
"New" channels: Will any area(s) of concentrated flow be channelized (deepened,
widened, or straightened) or otherwise altered? I J No I Ji Yes If only slightly
r-· shaped, see "Swales" in this Part. If creating side banks, provide information below.
-0 c t----------------------------------< ~ l!! Will design replicate natural channel? c:J Yes c:J No If "no", for each instance
a. ~ describe section shape & area, flow line slope (min. & max.), surfaces, and 100-year
~ w design flow, and amount of freeboard:
2? gj Instance 1: NIA
IOI a.
.5 ~
Instance 2: NIA
) Bl Instance 3: NIA
u
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 16 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.8)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
Existing channels {small creeks}: Are these used? J........J... No I I Yes
If "yes" provide the information below.
Will small creeks and their floodplains remain undisturbed? L ii Yes I _ j No How
many disturbance instances? Identify each planned location:
NIA
For each location, describe length and general type of proposed improvement
(including floodplain changes):
NIA
For each location, describe section shape & area, flow line slope (min. & max.),
surfaces, and 100-year design flow.
NIA
'O Q)
:::J .!: c Watercourses {and tributaries}: Aside from fringe changes, are Regulatory 0 Watercourses proposed to be altered? L J No D Yes Explain below. ~
Ill c Submit full report describing proposed changes to Regulatory Watercourses. Address Q) existing and proposed section size and shape, surfaces, alignment, flow line changes, E Q) length affected, and capacity, and provide full documentation of analysis procedures > 0 and data. Is full report submitted? D Yes D No If "no" explain: .... a. E NIA -
Qi c c ro All Proposed Channel Work: For all proposed channel work, provide information ..c
(.) requested in next three boxes.
If design is to replicate natural channel, identify location and length here, and describe
design in Special Design section of this Part of Report.
NIA
Will 100-year flow be contained with one foot of freeboard? I 4 Yes c:;J No If
not, identify location and explain:
NIA
Are ROW I easements sized to contain channel and required maintenance space?
L J Yes I -J No If not, identify location(s) and explain:
NIA
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 17 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.9)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
How many facilities for subject property project? For each provide info. below.
For each dry-type facilitiy: Facility 1 Facility 2
Acres served & design volume + 10%
100-yr volume: free flow & plugged
Design discharge (10 yr & 25 yr)
Spillway crest at 100-yr WSE? D yes I I no I J yes I I no
Berms 6 inches above plugged WSE? '-~1 yes l I no L _;I yes I _ l no
Explain any "no" answers:
Detention requirements for the Lofts development and Manuel Drive will be determined with the Lofts
"' construction documents. The size of this facility has not yet been determined. Manuel Drive will not be QJ >-constructed if the Lofts project is not developed. The entire Lofts project, including Manuel Drive, totals
DI 2.426 acres.
For each facility what is 25-yr design Q, and design of outlet structure?
0 Facility 1: NIA z
Bl Facility 2: NIA
Do outlets and spillways discharge into a public facility in easement or ROW?
C'-· Facility 1: D Yes Q No Facility 2: Q Yes r:J.No "O QJ If "no" explain: "' 0 NIA a. 0 ..... a...
"' For each, what is velocity of 25-yr design discharge at outlet? & at s12illwaj'.? QJ
~ Facility 1: & Facility 2: & ·u ro Are energy dissipation measures used? .D_No .D Yes Describe type and LL
c: location: NIA 0 :g
QJ
Qi
0
QJ ..... <l'. For each, is spillway surface treatment other than concrete? Yes or no, and describe:
Facility 1: NIA
Facility 2:
For each, what measures are taken to prevent erosion or scour at receiving facility?
Facility 1: NIA
Facility 2:
If berms are used give heights, slopes and surface treatments of sides.
Facility 1: NIA
Facility 2:
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 18 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Concel;!t and Design Parameters I Continued (Page 4.10)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
Do structures comply with 8-CS Specifications? Yes or no, and explain if "no":
I/)
Facility 1; NIA
Q)
E =~ 0 Q) Facility 2: Cll :::::s LL c c :p 0 c :;:::; 0 c 0 Q) .._.
Q) For additional facilities provide all same information on a separate sheet. 0
Are parking areas to be used for detention? J::1 No J::l Yes What is
maximum depth due to required design storm?
Roadside Ditches: Will culverts serve access driveways at roadside ditches?
0 No CJ Yes If "yes", provide information in next two boxes.
Will 25-yr. flow pass without flowing over driveway in all cases? J,;;:;.J_ Yes ..L...,J No
Without causing flowing or standing water on public roadway? __cJ_ Yes Q No
Designs & materials comply with 8-CS Technical Specifications? _.D_ Yes Q No
Explain any "no" answers:
NIA
('·
I/)
Ol .£
I/) Are culverts parallel to public roadway alignment? I 1 Yes I/) .r:::l No Explain: 0 .... I/) 0 Q) 2 >-
!DI Creeks at Private Drives: Do private driveways, drives, or streets cross drainage
Cll wr:s Jtat serve Above-Project areas or are in public easements/ ROW?
"'O 0 __ No D Yes If "yes" provide information below. Q) z
I/)
I :::::s How many instances? Describe location and provide information below. I/) t Location 1 : NI A Q) > "3 0
Q) Location 2: .... <{
Location 3:
For each location enter value for: 1 2 3
Design year passing without toping travelway?
Water depth on travelway at 25-year flow?
Water depth on travelway at 100-year flow?
For more instances describe location and same information on separate sheet.
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 19 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage ConceQt and Design Parameters I Continued (Page 4.11)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
Named Regulatort Watercourses (&Tributaries}: Are culverts proposed on these
facilities? lZl._ No ..c:::iL Yes, then provide full report documenting assumptions,
criteria, analysis, computer programs, and slud:/indings that support proposed
design(s). Is report provided? J::L Yes __ . · No If "no", explain:
-+::" Arterial or Major Collector Streets: Will culverts serve these types of roadways? Q) Q) L I No L .. :I Yes How many instances? For each identify the ..c tJl
Q) location and provide the information below.
tJl 1'i Instance 1: n/a Q) L.. >-:g_
DI~ Instance 2:
Instance 3: c 0 o~ Yes or No for the 100-year design flow: 1 2 3
Z E Bl~ Headwater WSE 1 foot below lowest curb top?
Spread of headwater within ROW or easement?
E C'· ro Is velocity limited per conditions (Table C-11)? tJl tJl g> "C Explain any "no" answer(s): ·-c ~ ro
0 c n/a L.. 0 (..) :p
>-ro ro u :;: ..Q
"C Q) ro .c Minor Collector or Local Streets: Will culverts serve these types of streets? e ·.::::
(.) (.) CJ No ...c::::l Yes How many instances? for each identify the ·-tJl -Q) -g "C location and provide the information below: c.. Q) ..... c.. Instance 1: n/a ro :;::;..
"C >-Instance 2: Q) c tJJ ro :::J '+-Instance 3: tJl 0 t tJl Q) Q) ~ (.) For each instance enter value, or "yes"/ "no" for: 1 2 3 :::Jc u ro Design yr. headwater WSE 1 ft. below curb top? Q) iii No No No
L.. c ~ ·-100-yr. max. depth at street crown 2 feet or less? No No No Q)
L.. 0 Product of velocity (fps) & depth at crown (ft) = ? E No No No
L.. g Is velocity limited per conditions (Table C-11)? No No No
Limit of down stream analysis (feet)? No No No
Explain any "no" answers:
n/a
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 20 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.12)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
All Proposed Culverts: For all proposed culvert facilities (except driveway/roadside
ditch intersects) provide information requested in next eight boxes.
Do culverts and travelways intersect at 90 degrees? ..c:J. Yes J:J. No If not,
identify location(s) and intersect angle(s), and justify the design(s):
NIA
Does drainage way alignment ch["~e within or near limits of culvert and surfaced
approaches thereto? .c:::L No ... Yes If "yes" identify location(s), describe
change(s), and justification:
NIA
Are flumes or conduit to discharge into culvert barrel(s)? ...t::l. No .C Yes If yes,
identify location(s) and provide justification:
NIA
~ Are flumes or conduit to discharge into or near surfaced approaches to culvert ends? Q) DJ No D Yes If "yes" identify location(s), describe outfall design treatment(s): :::J c
E NIA 0 ~
"' t
Q) ~ :::J Is scour/erosion protection provided to ensurJ::i term stability of culvert structural ()
components, and surfacing at culvert ends? Yes 0 No If "no" Identify
locations and provide justification(s):
NIA
Will 100-yr flow and spread of backwater be fully contained in street ROW, and/or
drainage easements/ ROW? L I Yes I .I No if not, why not?
NIA
Do appreciable hydraulic effects of any culvert extend downstream or upstream to
neighboring land(s) not encompassed in subject property? D No _D_ Yes If
"yes" describe location(s) and mitigation measures:
NIA
Are all culvert designs and materials in compliance with B-CS Tech. Specifications?
_r:::J_ Yes J:J. No If not, explain in Special Design Section of this Part.
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 21 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce12t and Design Parameters I Continued (Page 4.13)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
Is a bridge included in plans for subject property project? I l ~ No c::J Yes
If "yes" provide the following information.
Name(s) and functional classification of the roadway(s)?
NIA
What drainage way(s) is to be crossed?
:§:
Q) NIA
Cl 'U ·;::
al
A full report supporting all aspects of the proposed bridge(s) (structural, geotechnical,
hydrologic, and hydraulic factors) must accompany this summary report. Is the report
provided? D Yes t::l No If "no" explain:
NIA
Is a Stormwater Provide a general description of planned techniques:
~ Pollution Prevention See sheet 01 of the Manuel Drive construction drawings. Silt fence on west iii Plan (SW3P) '.:j side of Manuel Drive extension, silt control construction exit at end of a established for existing Manuel Drive, and inlet protection for 3 new inlets.
'-project construction? Q)
iii I. J No I Li Yes s:
Special Designs -Non-Traditional Methods
Are any non-traditional methods (aquatic echosystems, wetland-type detention , natural stream
replication , BMPs for water quality, etc.) proposed for any aspect of subject property project? .IZll. No r::J. Yes If "yes" list general type and location below.
NIA
Provide full report about the proposed special design(s) including rationale for use and
expected benefits. Report must substantiate that stormwater management objectives will not
be compromised, and that maintenance cost will not exceed those of traditional design
solution(s). Is report provided? -'=l_ Yes J::1 No If "no" explain:
NIA
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 22 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.14)
Stormwater Management Concept (continued)
Within Or Serving Subject Property (Phase, or Site) (continued)
Special Designs -Deviation From 8-CS Technical Specifications
If any design(s) or material(s) of traditional runoff-handling facilities deviate from provisions of
B-CS Technical Specifications, check type facility(ies) and explain by specific detail element.
_Cl Detention elements J::1 Drain system elements ..cJ. Channel features
J::J.. Culvert features r::J. Swales ..r:::l. Ditches .I:zl Inlets D..outfalls
..CJ.. Valley gutters .D. Bridges (explain in bridge report)
In table below briefly identify specific element, justification for deviation(s).
Specific Detail Element Justification for Deviation (attach additional sheets if needed)
1) Inlets on Dartmouth Drive Because of location of existing storm sewer, the 2-15' inlets may need to be
deeper than the normal 2.6' in order to "fit" the system
2) NIA
3) NIA
4) NIA
5) NIA
Have elements been coordinated with the City Engineer or her/his designee? For each item
above provide "yes" or "no", action date, and staff name:
1) No -being requested with this plan review.
2)
3)
4)
5)
Design Parameters
Hydrology
Is a map(s) showing all Design Drainage Areas provided? lZl_ Yes J::i No
Briefly summarize the range of applications made of the Rational Formula:
I 0-year storm was used to size pipes and inlets on Manuel Drive. New inlet on Dartmouth Drive was sized to
25-year storm per BICS guidelines.
Rational method was used in HGL calculations for existing system.
What is the size and location of largest Design Drainage Area to which the Rational Formula
has been applied? 3.33 ac acres
STORMWATER DESIGN GUIDELINES
Effective February 2007
Location (or identifier): PA-1.2
Page 23 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ____ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters l Continued (Page 4.15)
Design Parameters (continued)
Hydrology (continued)
In making determinations for time of concentration, was segment analysis used?
0 No .£ZJ. Yes In approximately what percent of Design Drainage Areas? JOO %
As to intensity-duration-frequency and rain depth criteria for determining runoff flows, were any
criteria other than those provided in these Guidelines used? JZJ... No D Yes If "yes"
identify type of data, source(s), and where applied:
For each of the stormwater management features listed below identify the storm return
frequencies (year) analyzed (or checked), and that used as the basis for design.
Feature Analysis Year(s) Design Year
Storm drain system for arterial and collector streets JO-year JO year
Storm drain system for local streets JO-year JO-year
Open channels NIA NIA
Swale/buried conduit combination in lieu of channel NIA NIA
Swales NIA NIA
Roadside ditches and culverts serving them NIA NIA
Detention facilities: spillway crest and its outfall NIA NIA
Detention facilities: outlet and conveyance structure(s) NIA NIA
Detention facilities: volume when outlet plugged NIA NIA
Culverts serving private drives or streets NIA NIA
Culverts serving public roadways NIA NIA
Bridges: provide in bridge report. NIA NIA
Hydraulics
What is the range of design flow velocities as outlined below?
Design flow velocities; Gutters Conduit Culverts Swales Channels
Highest (feet per second) -Mi ?.\ 9.5 fps NIA NIA NIA
Lowest (feet per second) Ml 2.0 7.6 fps NIA NIA NIA
Streets and Storm Drain Systems Provide the summary information outlined below:
Roughness coefficients used:
For conduit type(s) n = O.OJ3
STORMWATER DESIGN GUIDELINES
Effective February 2007
For street gutters:
Coefficients:
Page 24 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Conce~t and Design Parameters I Continued (Page 4.16)
Design Parameters (continued)
Hydraulics (continued)
Street and Storm Drain Systems (continued)
For the following, are assumptions other than allowable per Guidelines?
Inlet coefficients? I i'.J No L J Yes Head and friction losses l Z I No ..ct Yes
Explain any "yes" answer:
In conduit is velocity generally increased in the downstream direction? .c:::J. Yes rzJ No
Are elevation drops provided at inlets, manholes, and junction boxes? IZJ Yes Q No
Explain any "no" answers: Velocity is increasing in proposed system, by existing storm sewer system that
Manuel extension will tie onto is not increasing in velocity in downstream direction
-see Exhibits 9. IB and 9.28
Are hydraulic grade lines calculated and shown for design storm? tzl Yes J:J.No
For 100-year flow conditions? r::J Yes ..[ZJ No Explain any "no" answers:
Because this was a street project only I 0-year design storm was required for the pipes.
What tailwater conditions were assumed at outfall point(s) of the storm drain system? Identify
each location and explain:
Shown on attached HGL calculations at "OUT" -Flow line (264') of 30" RCP discharging into Wolf Pen Creek. This
pipe has free outfall in I 0-year conditions because the pipe outfall is several feet above the creek flowline.
Open Channels If a HEC analysis is utilized, does it follow Sec Vl.F.5.a? .D. Yes ..r::J No
Outside of straight sections, is flow regime within limits of sub-critical flow? ..D Yes ..D. No
If "no" list locations and explain:
n/a
Culverts If plan sheets do not provide the following for each culvert, describe it here.
For each design discharge, will operation be outlet (barrel) control or inlet control?
n/a
Entrance, friction and exit losses:
n/a
Bridges Provide all in bridge report
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 25 of 26 APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ____ _
SECTION IX
APPENDIX D -TECHNICAL DESIGN SUMMARY
Part 4 -Drainage Concept and Design Parameters Continued (Page 4.1 7)
Design Parameters (continued)
Computer Software
What computer software has been used in the analysis and assessment of stormwater
management needs and/or the development of facility designs proposed for subject property
project? List them below, being sure to identify the software name and version, the date of the
version, any applicable patches and the publisher
Microsoft Excel 2003 Service Pack 2
Part 5 -Plans and Specifications
Requirements for submittal of construction drawings and specifications do not differ due to use of a
Technical Design Summary Report. See Section Ill, Paragraph C3.
Part 6 -Conclusions and Attestation
Conclusions
Add any concluding information here:
See conclusion contained within executive summary.
Attestation
Provide attestation to the accuracy and completeness of the foregoing 6 Parts of this Technical
Desi n Summa Draina e Re ort b si nin and sealin below.
"This report (plan) for the drainage design of the development named in Part B was prepared
by me (or under my supervision) in accordance with provisions of the Bryan/College Station
Unified Drainage Design Guidelines for the owners of the property. All licenses and permits
quired by any and all state and federal regulatory agencies for the ~roposed drainage
rovements have been issued or fall under applicable general pe~.Q~'r°i''''
(Affix Se~~·"* ........... ~:IS'\
State of Texas PE No._1_1""""(£'-'b_q __
STORMWATER DESIGN GUIDELINES
Effective February 2007
Page 26 of 26
"'* .· ·.-ii'\ f ... ... * * : .. : ..... ~ vER.oNicA.:i.i.MoR~A~.i
\
······························ :er if ~·~ 77689 :'41 p rp~\ ~...-~;
11 O~;:_.~~G1s1E.~~·"&.;;f ~ •1 '-'.$' ......... ~.E
APPENDIX. D: TECH. DESIGN SUMMARY
As Revised ___ _
General Location
Troy Subdivision
Lot 1, Block One
This tract is located on the southwest side of Dartmouth Drive approximately 750 feet
south along Dartmouth from the Dartmouth-Holleman intersection, on a hill overlooking Wolf
Pen Creek.
J>roperty Description
The tract under consideration totals 13. 62 acres ofland and is currently vacant, abandoned
pasture. It is bounded on the northwest by a developed multi-family housing subdivision, KFO
Addition, and on the southeast by a single family subdivision, Brentwood. The tract is currently
zoned PUD-2.
Primary Drainage Basin Description
The generally well-graded tract is near the highest point in the vicinity, with the top of the
hill located approximately 300' from Dartmouth on the southeast side. Currently there are two
drainage areas.The north drainage area of 5.26 acres drains in a northerly direction in a sheet
flow across undeveloped land to Wolf Pen Creek. The south drainage area of8.36 acres drains in
a sheet flow to the south toward an abandoned stock tank, with overflow from this structure
flowing around the dam back to the northeast and into a 20' wide channel which is part of the
existing Brentwood drainage system.
The proposed project will consist of constructing a concrete detention facility with a
landscaped bottom for the drainage from area I and reshaping the existing stock tank for the
APPENDIXC
drainage from area II. This project will not signifcantly alter the long standing drainage patterns.
The Troy Subdivision 13. 62 acre tract is not within the flood plain as depicted on the
current flood map, FEMA-FIRM Community Panel No. 48041C0144C, July 1992. The site is
not generally considered to be a drainage problem.
Drainage Facility Design (See Accompanying Runoff Calculations and Hydrographs ).
Drainage Area I
This area is the north drainage area of the property. Water will flow through the system
primarily using surface routes such as the depicted centrally depressed parking and drives. To
prevent excess surface flow, use is als6 made of sumped inlets and underground drainage piping.
After the water passes through the detention area outlet control structure ( a v-notch weir and
sluice ) the flow is routed into a channel with sluice openings and then returns the drainage to its
natural sheet flow toward Wolf Pen Creek.
Using the rational method, the pre-development Q for the 100 year storm event is 23 .20
cfs, with a runoff volume of 20,877 cubic feet. Post development Q is is 43.32 cfs with a runoff
volume of 38,091 cubic feet. The required storage on-site is therefore 17,214 cubic feet . The
detention area provided by the design has a useable storage volume of 18,861 cubic feet, leaving
a surplus detention volume of 164 7 cubic feet.
Drainage Area II
This area is the south drainage area of the property. Like Drainage Area I, water will flow
through the system by overland sheet flow and surface routes in the parking and drive areas, as
well as through the subsurface drainage system depicted. After passing through the the detention
area outlet control weir, water will be conducted through a 36" reinforced concrete pipe and then
drains into the existing Brentwood 20' wide drainage and utility easement
Using the rational method, the predevelopment Q for the 100 year storm event is 36.87
cfs, with an associated runoff volume of33,181 cubic feet. After development, Qpost jumps to
86.86 cfs, and a runoff volume 78, 172 cubic feet. The required on-site storage is 44,991 cubic
feet . The postdevelopment quantities account for any off site runoff that may enter this detention
pond as a result of the development that will take place. The drainage area provided has a total
capacity of 49,617 cubic feet. Pre-existing excess storage is present in the amount of 29,596 cubic
feet. These quantities will not cause any backwater effects in the storm sewer entering the
detention area.
Conclusion
The design depicted is· well within the standards of good practice and of the City of
College Station Drainage Policy. There is adequate storage capacity on-site to handle the
anticipated flows. The excess capacity may be used in the future to drain the lots which will
someday line the northeast side of the proposed extension of Cornell Drive, although this depends
on remote parties and is not specifically contemplated at this time.
( 'lllCHTWOOO
'
SECTION TWO
VOlUVt JS• l'AOt Ut
DRAINAGE AREA 11
9.36~
.-""\ __ ,
1f --,--_.a ,I' ~ . ,
I tHTWO
ICC ION T~9.t>n: votvwr1~;;, l'A'llt !IS .~LOCK ON[
DRAINAGE
. "
MAP
I t I •,
DRAINAGE AREA I
·5.26AC
: .
llltNTWOOO StcTJON rlVt
VOl.Ullt 311 l'AOE t7S
'I'
..
N.T.S.
DRAINAGE AREA I
Routi ng
10 Year
Weir Slice Gate
Peak Flows Angle= 30.00 Width= 3.75
15.83 28.89 Crest Length = 0.30 Height= 0.50
@Height= 3.00
Tc Qm QQQfil Y. Vtotal tl Qout ds/dt Vstorage ttgorage
0 0.00 0.00 0.0 0.0 0.00 0.00 0.0 0.0 0.00
2 3.17 5.78 346.7 346.7 0.09 2.47 1.7 198.5 0.01
4 6.33 11 .56 1040.0 1238.6 0.32 4.67 6.8 810.4 0.04
6 9.50 17.33 1733.4 2543.8 0.65 6.69 15.5 1862.5 0.09
8 12.66 23.11 2426.8 4289.3 1.10 8.68 28.1 3366.9 0.16
10 15.83 28.89 3120.1 6487.1 1.66 10.68 44.4 5325.2 0.25
12 14.25 26.00 3293.5 8618.6 2.21 12.31 60.3 7239.2 0.34
14 12.66 23.11 2946.8 10185.9 2.61 13.38 72.0 8644.3 0.40
16 11 :08 20.22 2600.1 11244.4 2.88 14.06 80.0 9597.8 0.45
18 9.50 17.33 2253.4 11851 .2 3.03 14.42 84.5 10142.4 0.47
20 7.92 14.45 1906.7 12049.1 3.08 14.56 85.9 10310.6 0.48
22 6.33 11.56 1560.1 11870.7 3.04 14.43 84.4 10131 .4 0.47
24 4.75 8.67 1213.4 11344.8 2.90 14.12 80.3 9631.5 0.45
26 3.17 5.78 866.7 10498.2 2.69 13.59 73.6 8835.5 0.41
28 1.58 2.89 520.0 9355.5 2.39 12.83 64.8 7770.8 0.36
30 0.00 0.00 173.3 7944.1 2.03 11 .82 53,9 6465.4 0.30
32 0.0 6465.4 1.65 10.66 42.6 5116.5 0.24
34 0.0 5116.5 1.31 9.49 32.6 3907.7 0.18
36 0.0 3907.7 1.00 8.29 23.7 2841.2 0.13
38 0.0 2841 .2 0.73 7.07 16.0 1919.8 0.09
40 0.0 1919.8 0.49 5.81 9.6 1147.1 0.05
42 0.0 1147.1 0.29 4.49 4.4 529.0 0.02
44 0.0 529.0 0.14 3.05 0.0 0.0 0.00
46 0.0 0.0 0.00 0.00 0.0 0.0 0.00
48 0.0 0.0 0.00 0.00 0.0 0.0 0.00
50 0.0 0.0 0.00 0.00 0.0 0.0 0.00
52 0.0 0.0 0.00 0.00 0.0 0.0 0.00
54 0.0 0.0 0.00 0.00 0.0 0.0 0.00
56 0.0 0.0 0.00 0.00 0.0 0.0 0.00 .
58 0.0 0.0 0.00 0.00 0.0 0.0 0.00
60 0.0 0.0 0.00 0.00 0.0 0.0 0.00
Routing for Area I
10 Year Storm
30 ~~~~~~~~~~~~~~
25 "'•
.--.. 20 U) .
~15
a 10
5
=-=i==~~~::~: :~~:==~==:=====:::==:-_:-_::-=:~==:== ' ',~ -·------·-;L______ ·-·-·-----·-----~'----·· . --·--··--··-·-·---··-··-··------··--·-----·---··-·-----··-·-·--·-·--·
I .,
i '~. ·--·-·---··/.-·-·--·--·-···--·-·-····----·-·-·-·········--·-·-·-·--·--·-·-······"~,-·-····-············--·-·-·-·-···-··-·-·-·-··--·--·-·-·--·--···-·-·-·--············-·--·-·---------·-·-·-··-
/ ~ ·,,
';.. -··-·· -·-······-·-·-···--··-----··---·------···-··--·--·-·-··------·-...,.;_~ --·--·-·-·--··-··---------···---------·--·-··---·--·-
0 .__-1----+--~+------+----+--~----!----+--~~~
0 10 20 30 40 50
Time (min)
_.._ Qpre --.--Qpost ~ Qout