HomeMy WebLinkAbout30 Development Permit 602 Legacy Construction Office BuildingFACSIMILE COVER SHEET
CITY OF COLLEGE STATION
DEVELOPMENT SERVICES
1101 Texas Avenue South, PO Box 9960
College Station, Texas 77842
Phone ( 409)764-3570 I Fax ( 409)764-3496
Date: October 29, 1999 #of pages included cover: 8
If y ou did not rece ive a complete fax, please call our office immediately for a new transmittal.
TO: ____ T_o_n_y_J_on_e_s ___ _ FAX: 695-2941 ----~----
COMPANY: Legacy Construction
RE: Drainage Study for your new office building.
FROM: __ --'N~at~a=lie~R~u=iz"-----PHONE: ( 409)764-3570
COMPANY: ______ C=i~ty.__o.=o..=f~C~o=ll=e=ge~St=a=ti=on==-----------
REMARKS: D Urgent ~For your review D Replay ASAP D FYI
Attached is a copy of the drainage report for your new office building. The
drainage report that we were unable to locate was on the All Season's
Storage Buildings next door. I hope this helps with the drainage letter that
you're working on for your addition. Let me know if you need additional
information.
Thank you, Natalie
\
';
DRAINAGE COMPUTATIONS
for
A Site And Grading Plan
Legacy Construction Office Building
College Station, Brazos County, Texas
Prepared for:
Legacy Construction
2114 Southwood Drive
College Station , Texas 77845
Prepared by:
*July, 1998*
LOCATION:
Drainage Computations
For
A Site & Grading Plan
To
Legacy Construction Office Building
College Station, Brazos County, Texas
SUMMARY
The subject site is located on Lot 1, Block One of the C.S.L. Of Texas, Inc . Addition approximately 200
feet northwest of the intersection of Sebesta Road and the east frontage road of Texas State Highway No .
6 .
GENERAL:
Included with the development of Lot 2, Block One of the C.S.L. OF Texas, Inc . Addition in April of
1997 was an evaluation in the form of a bound drainage report for the existing drainage channel that lies
between Lot 1 and Lot 2, Block One of the C. S.L. Of Texas . Inc. Addition. It was found in same drainage
report that the drainage channel functions as a detention pond and that there is enough capacity within the
existin channel to facilitate the existing mini-storage complex located on Lot 2, Block One of the C.S .t.
Of Texas, Inc . on as we an sever acres o a p een · un eve Oped u pstream areas . Uti ization o
this excess storage capacity Fs on a first-come-first-serve basis . It is the intention of the developer of Lot
1, Block One , C.S.L. Of Texas , Inc. Addition to utilize this same aforesaid available detention volume
which is incorporated within the existing drainage channel.
As per the original drainage report as referenced above it is apparent that there is adequate storage volume
within the existing drainage channel to facilitate Lot 1, Block One , C.S.L. Of Texas, Inc . Addition while
still supplying more than the required freeboard during the 100-year ultimate condition storm event.
11111111111111~1•r111111111~1111111111111111111111111111111111:::1
Site Area 0.49 Acres
Pervious Area : 0.49 Acres
Impervious Area : 0.00 Acres
Run-Off Coefficient ("Cwt"): 0.40
Time Of Concentration ("T/c"):
Woodlands: Low Elevation :
High Elevation :
Distance (Feet):
Slope(% Grade):
Velocity ("Vw"):
Time :
Pastures: Low Elevation :
High Elevation:
Distance (Feet):
Slope (% Grade):
Velocity ("Vp"):
Time:
Pavements: Low Elevation :
High Elevation :
Distance (Feet):
Slope (% Grade):
Velocity ("Vpave"):
Time :
Total Travel Time :
Hourly Intensity Rates ("I"): 2-Year: 6 .33
5-Year: 7 .69
10-Year: 8.63
25-Year: 9 .86
50-Year: 11 .15
100-Year: 11.64
Peak Discharge Rate C'O"): 2-Year: 1.24
5-Year: 1.51
10-Year: 1.69
25-Year: 1.93
50-Year: 2.18
100-Year: 2.28
1
c = 0.40
c = 0 .98
0.00
0.00
0 .00
0.00
0.00 Feet I Second
0 .00 Minutes
0.00
0.00
0 .00
0.00
0.00 Feet I Second
0.00 Minutes
0.00
0 .00
0.00
0 .00
0 .00 Feet I Second
0 .00 Minutes
10 .00 Minutes
Inches I Hour
Inches I Hour
Inches I Hour
Inches I Hou r
Inches I Hour
Inches I Hour
Cubic Feet I Second
Cubic Feet I Second
Cubic Feet I Second
Cubic Feet I Second
Cubic Feet I Second
Cubic Feet I Second
..
Tributary Area ("A"): 0.49 Acres
Pervious Area: 0.19 Acres c = 0.40
c = 0.98 Impervious Area : 0.30 Acres
Run-Off Coefficient ("Cwt"): 0.76
Time Of Concentration ("T/c"): 1 O Minutes (Min)
Hourly Intensity Rates ("I"): 2-Year: 6 .33 Inches I Hour
5-Year: 7.69 Inches I Hour
10-Year: 8.63 Inches I Hour
25-Year: 9.86 Inches I Hour
50-Year: 11 .15 Inches I Hour
100-Year: 11.64 Inches I Hour
Peak Discharge Rate ("Q"): 2-Year: 2 .34 Cubic Feet I Second
5-Year: 2.85 Cubic Feet I Second
10-Year: 3.19 Cubic Feet I Second
25-Year: 3.65 Cubic Feet I Second
50-Year: 4 .12 Cubic Feet I Second
100-Year: 4 .31 Cubic Feet I Second
Predevelopment Post-Development Increase
2-Year: 1 .24 Ft3/sec 2 .34 Ft3/sec 1 . 1 O Ft3/sec
5-Year: 1.51 Ft3/sec 2.85 Ft3/sec 1.34 Ft3/sec
10-Year: 1.69 Ft3/sec 3.19 Ft3/sec 1.50 Ft3/sec
25-Year: 1 . 93 Ft3/sec 3.65 Ft3/sec 1. 72 Ft3/sec
50-Year: 2.18 Ft3/sec 4 .12 Ft3/sec 1.94 Ft3/sec
100-Year: 2.28 Ft3/sec 4 .31 Ft3/sec 2.03 Ft3/sec
2
E ~I GI ~IEE RI ~I G
CONSULTIN G ENGIN EE R ING & LAND SURV EYING
4444 CARTER CREEK PKWY, SUITE 108 BRYAN , TEX AS 7 7 802 (409J 846-2688 (409) 8 46-3094
August 6,1998
Mr. Paul Kasper
Department of Development Services
P.O. Box 9960
College Station, Texas
co~.JIPLIAf\JCE
AUG 1 2 199 8
RE: Supplemental Data for a Drainage Report for a Site and Grading Plan for
Legacy Construction Office Building, College Station, Brazos County, Texas.
Dear Mr. Kasper,
As per your request for additional data m regards to the above referenced
project we offer the following:
The drainage channel immediately adjacent to the subject project functions as
a detention pond due to the metering effect of the Existing 42" Diameter
Reinforced Concrete pipe which runs in a northwest direction under the east
By-Pass frontage road.
"As-Built" surveys of same channel estimate the available storage capacity of
the drainage channel is 105,088 cubic feet at elevation 275.00 The current
construction (Mini Storage Complex and Bug Blasters) and adjacent areas
tributary to the drainage channel produce the following Depth/Volume
Estimations.
Elev. Frequency Depth Volume
270.11 5-year storm: 1.81 feet 16,579 C.F.
270.39 10-year storm: 2.0 9 feet 20,915 C.F.
270.80 25-year storm: 2.50 feet 27,265 C.F.
271.33 50-year storm: 3.03 feet 33,683 C.F.
271.55 100-year storm: 3.25 feet 35,896 C.F.
Please note that the above Tabulation was derived from the previously
submitted Drainage Report for the Mini Storage Complex located within the
C.S.L. of Texas, Inc. Addition of Record (May, 1997).
As previously stated the estimated storage capacity of the channel is lOS,088
cubic feet at Elevation 27S.00.
Breaking down each storm volume (S-100 y ear) as a percentage of total
available storage volume produces the following results:
S-y ear:
10-year:
2S-y ear:
SO-y ear:
100-y ear:
16% of Total Available Volume
20% of Total Available Volume
26% of Total Available Volume
32% of Total Available Volume
34% of Total Available Volume
of the 105,088 cubic feet of available storage volume only approximately
3S ,896 cubic feet is utilized by the anticipated 100-y ear storm event under
current developed conditions.
The anticipated storm volumes associated with the development of the subject
project (Legacy Construction Office) are Presented as follows:
Frequency Volume
S-y ear: 4208 cubic feet
10-year 4723 cubic feet
25-year S394 cubic feet
SO-y ear 6098 cubic feet
100-y ear 6367 cubic feet
Please note that the above anticipated Volumes or increased run-off Volumes
only as the Subject Tract was included in the original storm water analy ses as
mentioned previously (May , 1997).
The following tabulations represents the modified Depth/Volume estimates as a
function of development of the subject project:
Fre quency Volume Depth Percentage of Total Volume
S -year 20,787 C.F. 2.08 ft. 20%
10-y ear 25,638 C.F. 2.40 ft. 24%
2S-y ear 32,6S9 C.F. 2.93 ft. 31 %
50-year 39 ,781 C.F. 3.64 ft. 38%
100-y ear 42,263 C.F. 3.88 ft . 40%
From the data presented above it is apparent that the increased run-off due to
the development of the Legacy Office Building can be facilitated within the
existing channel while allowing the possibility for other upstream areas tribute
to the drainage channel to develop without detention also.
A four foot (4') wide drainage flume exits the subject project and ties to the
existing 6 ' wide concrete pilot channel in the bottom of the aforesaid drainage
channel. Velocity is of concern at this specific juncture. Efforts to calculate a
correct velocity at same location most likely will produce an erroneous answer
due to the steepness of the sideslope of the channel and the transitionary
quality of the flow regime, therefore it would be advisable to assume that high
velocities occur and to supply energy dissipation blocks at the bottom of the
proposed flume where it ties to the existing 6 ' wide concrete pilot channel.
Please note the revisions to the Site and Grading Plan addressing the inclusion
of said energy dissipation Block.
If y ou have any questions or problems with the above items please contact me
at y our earliest opportunity (409) 846-2688 .
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DEVELOPMENT PERMIT
PERMIT NO . 602
LEGACY CONSTRUCTION OFFICE BUILDING
FOR AREAS OUTSIDE THE SPECIAL FLOOD HAZARD AREA
RE: CHAPTER 13 OF THE COLLEGE STATION CITY CODE
SITE LEGAL DESCRJPTION:
Lot 1, Block One, C.S.L. of Texas, Inc . Addition
OWNER:
Tony Jones
2114 Southwood Drive
College Station, Texas 77845
409-695-9413
DRAINAGE BASIN:
Bee Creek Trib. A
TYPE OF DEVELOPMENT:
SITE ADDRESS:
State Highway 6 Frontage East
This permit is valid for site construction as shown on the approved plans.
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. The Owner and/or Contractor shall assure that all disturbed
areas are sodden and establishment of vegetation occurs prior to removal of any silt fencing or hay bales
used for temporary erosion control. The Owner and/or Contractor shall also insure that any disturbed
vegetation be returned to its original condition, placement and state. The Owner and/or Contractor shall
be responsible for any damage to adjacent properties, city streets or infrastructure due to heavy machinery
and/or equipment as well as erosion, siltation or sedimentation resulting from the permitted work.
Any trees required to be protected by ordinance or as part of the landscape plan must be completely fenced
before any operations of this permit can begin .
In accordance with Chapter 13 of the Code of Ordinances of the City of College Station, measures shall be
taken to insure that debris from construction, erosion, and sedimentation shall not be deposited in city
streets, or existing drainage facilities .
All
Date ~ /
Contractor Date
07 /01 /98 11:02 DEVELOP MENT SVC qg,tf~~05 .
60:;. Figure Xfi
Development Permit
City of College Station, Texas
ff /tJtJ~ Aff r&e
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(IF /,(/rf?AGf'R~nJ~
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Site Legal Description: loT l 1 aL(?c.4.<::.. ~ >Jtr -c. S.L · Ofi ~ 1 I kX... ~ITT oA.J
~114 So~u.:roop °'2-1.IJC
Site Owner: ~:( J~------
Architect/
Engineer :~ pU L.t~AJl.
Address: 'S!! i'lP • a:uet.e SMDW(tX:i?~'{.S
Telephone: (eq £ -1'-f f"'3
4-4'{-4 ~~ ~ /t;t
Address: '2Jl.'t'tHV1 "Tbat:r -0 80)..
Telephone No: -=L~ ~4' -U fi~ .
..Zll <-l S°""°""wocco ~LS
l e;t.,fv"( ~'-'?vcSOOk> Address : ~ SMl""-'·~· 72T5~
Telephone No : lrf?:"-C:Z<.f .l't
Contractor:
Date Application Filed : --------Approved: --~-~-------
Application is hereby made for the following development specific waterway alterations :
t
0
0
0
No ~ ~ :R-2 'PFLF! vV&0 w M\1it2.,lA.l'A-1 •
Application Fee
Signed Certifications
\
Drainage and erosion control plan, with supporting Drainage Report two (2) copies each .
Site and Construction Plans, with supporting Drainage Report two (2) copies each .
Other:
~~~--~~~----~---~-~--~
ACKNOWLEDG!v1ENTS :
I, Th"J'f ..5o"-.Sb4. ...... _ ____, design engineer/owner, hereby acknowledge or affirm th a t
The information and conclusions contained in the above plans and support ing documents comply
with the current .-cquireme11ts of the City of College Station, Texas City Code, Chapter 13 and its
associated Drainage Policy and Design Sta11dards.
As a condition of approval of this permit application, I agree to construct the improvements
proposed in this application according to these documents and the requirements of Chapter 13 of
the College Station City Code.
Property Owner(s) Contractor