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HomeMy WebLinkAbout49 DP Aggieland Fitness SH 6 South 035FOR OFFICE USE ONLY P&Z CASE NO.: 03 · / 5 DATE SUBMITTED: / • J5· {fj SITE PLAN APPLICATION {i5 .. 03 /o :s ow MINIMUM SUBMITTAL REQUIREMENTS $200.00 Site plan application and review fee . $200 .00 Development perm it fee . $600.00 Public infrastructure inspection fee, if applicable. (This fee is payable if construction of a public waterline, sewerline, sidewalk, street or drainage facilities is involved .) Ten (10) folded copies of site plan. A copy of the attached site plan checklist with all items checked off or a brief explanation as to why they are not checked off. Parkland Dedication requirement approved by the Parks & Recreation Board, please provide proof of approval (if applicable). NAME OF PROJECT A66. I ELAl\lp hTIV€SS C..e:.Nn:::g ADDRESS 5-H (p 3£u 1Jh LEGAL DESCRIPTION L1c...1 <. CRcEt< Su!!>Dt 01 £.101'.l > P1-t A'i> E I 1 Lor I > 8L0c..1e. (vo'-· 4~2o J P<·,. er:£) A PPLICANT (Primary Co ntact for the Project): Name Ro1?EB-I L . PA'Ct-JE' . Ji<.. Strn et Address 12:?~ BHe(?ALD P1c:..vu'{ . 'Sc> 1 IE t o4 City Cou..£<-,.E STA"OOAJ State TUAS Z ip Code 7_7_&_4-_S ___ _ P ~on e Number (4 7 :i) U.jC..-727Z Fax Number {'=t 7<1 J t-etla -.& l l 4 PROPERTY OWNER'S INFORMATION: Name Skve.. Lompee.. E-Mail _____________ _ Street Address 141'1 Hti.l?PE-(2.S fe::eg.'C 12..o. City Cou..£.G,:e:: SJ7;vtl.Ol"J State Tet<As Zip Code _7~7~B~1=+-"'5 ____ _ Phone Number (q7q"') §40 -739, a Fax Number ____________ _ ARCHITECT OR ENGINEER'S INFORMATION : Name R. L. Pa.'(oc; ~ Ass0a~ h ) l11.::::. · E-Mail RPayoe e I<. b Pa.1'nc:... c..orn StreetAddress 10e'1 EMe&AbO ~IS.WA:( Sun-e: Jo4: City Cou..e<-4 sm:nor-J State_\ eyA?:;;....L..;:'-'-"•-----Zip Code 17848 Phone Number {'17'1) CPCJ(p -72 72. Fax Number _...(4_._J_,_q-=-)..__~=----=&,;.._--=B"'"""l'-'-1 __,4 ___ _ OTHER CONTACTS (Please specify type of contact , i.e. project manager, potential buyer, local contact , et c.) Name __________________ _ .E-Mail _____________ _ Street Address _________________________________ _ City ______________ State _______ _ Zip Code ________ _ Phone Number _______ _ Fax Number _____________ _ Site Plan 1/1 3/03 1of3 CURRENTZONING ___ C:. __ ·-'----·-------------------~ PRESENTUSEOFPROPERTY ·--~~D~n_D--'e~~-l-Dfr--e~d"----------------- PROPOSED USE OF PROPERTY CnMM5R_GI AL -£1 Tl\J e.ss ~ VARIANCE(S) REQUESTED AND REASON(S) __ tJ_t::>--'Vl,____ ______________ _ #OF PARKING SPACES REQUIRED 80 #OF PARKING SPACES PROVIDED 8Cp -----'----- MUL Tl-FAMILY RESIDENTIAL Total Acreage __ Floodplain Acreag~ __ Housing Units __ __ # of 1 Bedroom Units # of 2 Bedroom Units -- __ # of 3 Bedroom Units # of 4 Bedroom UnHs FOR 2 BEDROOM UNITS ONLY _. __ #Bedrooms = 132 sq. ft . __ # Bedrooms < 132 sq . ft. PARKLAND DEDICATION #of Multi-Family Dwelling Units __X$452 = $ __#of acres in floodplain __ # of acres in detention __ # of acres in greenways __ date dedication approved by Parks Board COMMERCIAL Tota1Acreage. l.G7f -P~t.Jc. ( Building Square Feet ll 1 '1~u . 1 Floodplain Acreage JA-lJ ftc.. NOTE: Parkland Dedication fee is due prior to the issuance of a Building Permit. The applicant has prepared this application and certifies that the facts stated herein and exhibits attached hereto are true and correct. SITE PLAN CHECKLIST Site Plan 1/13/03 2 of3 SUPPLEMENTAL DEVELOPMENT PERMIT INFORMATION Application is hereby made for the following developme nt specific site/waterway alterations: ACKNOWLEDGMENTS : ~ o5ti0\-.. f-S c.\,,. .. J~-L I, __ ,\design engineer/owner, hereby acknowledge or affir m that : The information and conclusions contained in the above plans and supporting documents comply with the c urren t requirements of the City of College Station , T exas City Code, Chapter 13 and its associated Dra ina ge Policy and Des ign Standards . A s a condition of approval of this permit application, I agree to co nstru ct the improveme nts proposed in this application according to these documents and the req uiremen ts of Ch ter 13 of the Cp~e~ Code . Property Owner(s) G o (~~: ... -c.~ CERTl:~AT~ps_:~~~t~ alterations within designated flood ha zard areas.) A.I, ~ <-fertify that any nonresidential structure on or proposed to be on this site as part of this appl ication is designated to prevent damage to the s ucture or i" contents as a result of f10 0d ing from the 100 year storm. Jr+P· 1-14--D z Engineer Date B . I, __ certify that the finished floor e levation of the lowest floor, inclu d ing any basement, of any residential structure , proposed as part of this appiication is at or a bove th e base flo od e1evation es tablished in the lates t Federal Insurance A d mini stration Flood HazarcJ Stu dy an .j ma ps, as amen d ed . Engineer f "?~··.'Js-, x,.Q,/~' ,I Date ft:.<>~ · •• g1s1E.~·· 0',;/ D. . I,-._, do c~f(~ttii1"~@ ~~ed alter~tion~ do not raise the level of the 100 year flood above elevation established rn the latest '~f»Af~rance Adminrstratr o n Flood Hazard Study. Eng in eer 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 w ith the plans and specifications submitted to and approved by th e City Engineer for the above named proje ct. All of ti1e app licable codes an d ord inances of the City of College Station shall app ly SITE PLAN CHEC KLIST Sit e Plan .DO C 0 8/0 I /02 I • or t 3 ( j Item No . 1 2 3 4 5 6 7 8 9 10 11 12 13 TEXCON GENERAL CONTRACTORS AGGIELAND FITNESS CENTER COLLEGE STAT ION, TEXAS CONSTRUCTION COST ESTIMATE PUBLIC INFRASTRUCTURE Estimated Description Quantity Waterline 6" Waterline -PVC (C900)-struct. 145 8" Waterline -PVC (C900)-struct. 24 8" Valve 6" Valve 24" x 8" Tapping Sleeve & Valve 8" M .J . Cross 1 8"x6" Reducer 2 6" 45 deg . M .J. Bend 2" Blowoff Assembly 6" x 2" Service Saddle Fire Hydrant Assembly Sanitary Sewer Tie-in to Existing Line 4' Manhole 2/28/03 Unit Price/Unit Total LF $28.00 $4 ,060 .00 LF $30 .00 $720 .00 EA $600 .00 $600 .00 EA $500 .00 $500 .00 EA $6,000 .00 $6 ,000 .00 EA $500 .00 $500 .00 EA $300.00 $600 .00 EA $250 .00 $250.00 EA $450 .00 $450 .00 EA $200 .00 $200 .00 EA $2,400 .00 $2,400 .00 Subtotal $16,280 .00 EA $300 .00 $300 .00 EA $3,000.00 $3,000 .00 Subtotal $3,300.00 Tota l Construction $19,580.00 ~-~ DEVELOPMENT PERMIT PERMIT NO . 03-05 Project: AGGIELAND FITNESS CENTER COLllGl STATION FOR AREAS OUTSIDE THE SPECIAL FLOOD HAZARD AREA RE: CHAPTER 13 OF THE COLLEGE STATION CITY CODE SITE LEGAL DESCRIPTION: Lick Creek Subdivision Phase I Block 1 Lot 1 DATE OF ISSUE: 04/02/03 OWNER: Steve Lumpee 1419 Harpers Ferry Road College Station , Texas 77845 TYPE OF DEVELOPMENT: SPECIAL CONDITIONS: SITE ADDRESS: 4050 State Highway 6 South DRAINAGE BASIN: Lick Creek VALID FOR 9 MONTHS CONTRACTOR: Full Development Permit All construction must be in compliance with the approved construction plans All trees must be barricaded, as shown on plans , prior to any construction. Any trees not barricaded will not count towards landscaping points . Barricades must be 1' per caliper inch of the tree diameter. Erosion control per the approved plans must be in place for the duration of project. No development will be allowed in the TxDOT ROW until TxDOT Driveway Permit is issued. The Contractor shall take all necessary pr_ecautions to prevent silt and debris from leaving the immediate construction site in accordance with the approved erosion control plan as well as the City of College Station Drainage Policy and Design Criteria . If it is determined the prescribed erosion control measures are ineffective to retain all sediment onsite , it is the contractors responsibility to implement measures that will meet City , State and Federal requirements. The Owner and/or Contractor shall assure that all disturbed areas are sodden and establishment of vegetation occurs prior to removal of any silt fencing or hay bales used for temporary erosion control. The Owner and/or Contractor shall also insure that any disturbed vegetation be returned to its original condition, placement and state. The Owner and/or Contractor shall be responsible for any damage to adjacent properties, city streets or infrastructure due to heavy machinery and/or equipment as well as erosion , siltation or sedimentation resulting from the permitted work . Any trees required to be protected by ordinance or as part of the landscape plan must be completely fenced before any operations of this permit can begin. In accordance with Chapter 13 of the Code of Ordinances of the City of College Station , measures shall be taken to insure that debris from construction, erosion , and sedimentation shall not be deposited in city streets, or existing drainage facilities. I hereby grant this permit for development of an area 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 I I 2. t0''1?/, I Zoo~ Date DP-AGGI ELAND FITNESS CENTER -(03-00100005) ENGINEERING REVIEW COMMENTS No. 1 1. Fire hydrant leads longer than 18 feet are considered main lines per Fire Hydrant Detail 1-C. Please provide profile of the 8-inch water line. Reviewed by: Carol Cotter Date: May 12, 2003 NOTE: Any changes made to the plans , that have not been requested by the City of College Station , must be explained in your next transmittal letter and "bubbled " on your plans . Any additional changes on these plans that have not been pointed out to the City of College Station will constitute a completely new review . Page 2 of 2 .. STAFF REVIEW COMMENTS NO. 1 Project: DP-AGGIELAND FITNESS CENTER-DEVELOPMENT PERMIT( 03-00100005 ) ENGINEERING 1. Dra in age letter required . How will runoff be d ischarged to cree k? Wh at type of ou tl et structure? What type of end treatment? 2 . Subm it Grad ing Plan showing proposed elevations. 3. Subm it Eros ion Contro l Plan . 4. Sub mi t TxDOT Dr iveway perm it. Rev iewed by : Carol Cotter Date: January 27 , 200 3 NO T E : Any changes made to the plans, that have not been requested by the City of College Statio n, must be explained in your next tra nsmittal lette r an d "bubbled " on you r plans. Any additional changes on these plans that have not been pointed out to the City , will constitute a completely new review . Staff Review Commen ts Page 2 of 4 CERTIFICATION I, Joseph P . Schultz, Licensed Professional Engineer No . 65889, State of Texas, certify that this report for the drainage design for the Aggieland Fitness Center in College Station, Texas, was prepared by me in accordance with the provisions of the City of College Station Drainage Policy and Design Standards for the owners hereof, with the exception that stom1 water runoff detention is not being required for this project since the site discharges directly into an existing drainage and immediately into the 100- year floodplain limits. Ginger t. Urso, P .E. TABLE OF CONTENTS AGGIELAND FITNESS CENTER CERTIFICATION ................................................................................................................................................................. 1 TABL.E OF CONTENTS ....................................................................................................................................................... 2 LIST OFT ABLES .................................................................................................................................................................. 2 INTRODU CTION .................................................................................................................................................................. 3 GENERAL LOCATION AND DESCRIPTION ................................................................................................................. 3 FLOOD HAZARD INFORMATION ................................................................................................................................... 3 DEVELOPMENT DRAINAGE PATTERNS ...................................................................................................................... 3 DRAINAGE DESIGN CRITERIA ....................................................................................................................................... 3 STORM WATER RUNOFF DETERMINATION .............................................................................................................. 3 STORM SEWER CULVERT DESIGN ............................................................................................................................... 4 STORM RUNOFF DESIGN CALCULATIONS ................................................................................................................. 4 CONCLUSIONS ..................................................................................................................................................................... 5 APPENDIX A ......................................................................................................................................................................... 6 Calculatio11 s EXHIBIT A ........................................................................................................................................................................... 16 Drainage Area Map LIST OF TABLES TABLE 1 -Rainfall Intensity & Runoff Data .......................................................................................... 3 TABLE 2 -Time of Concentration (tc) Equations .................................................................................. 4 2 DRAINAGE REPORT AGGIELAND FITNESS CENTER INTRODUCTION The purpose of this report is to provide the hydrolo g ical effects of the construction of the dome-structure building and parking area , and to show that the storm water runo ff will be controlled in such a manner so as to have minimal offsite or do wnstream imp act. GENERAL LOCATION AND DESCRIPTION The project is located on 2.27 acres out of a 4.02-acre tract located in College Station, Tex a s . Most of the site is open land with grass . A 0.477 acre portion on the northwest end along th e North Fork of Lick Creek is being dedicated as greenway. This area is primarily wooded . The existing ground elevations range from elevation 280 to elevation 292. The general location of the project site is shown on the vicinity map in Exhibit A. FLOOD HAZARD INFORMATION The project site is located in the Lick Creek Drainage Basin. The site is located in a Zone X Area according to the Flood Insurance Rate Map (FIRM) prepared by the Federal Emergency Management Agency for Brazos County, Texas and incorporated areas dated February 9 , 2000 , panel number 48041C0201 D. Zone X Areas are determined to be outside of the 500-yr floodplain. This site is not within the limit of study for the FIRM. However, the approximate 100-year floodplain limits were previously detem1ined by the City of College Station, and these limits were included on the Final Plat for the project. This floodplain area is also shown on Exhibit A. Most of the floodplain area for this tract is located in the Greenways Dedication Area. DEVELOPMENT DRAINAGE PATTERNS The storm water runoff from the site flows north into the State Highway 6 right-of-way or directly into the North Fork of Lick Creek . A majority of the runoff from the developed area will be diverted so that it enters the creek and the 100-year floodplain rather than the right-of- way; therefore, no detention is required for this project. The drainage area boundaries are shown on Exhibit A. DRAINAGE DESIGN CRITERIA The design parameters for the stonn sewer are as follows: • The Rational Method is utilized to determine peak storm water runoff rates for the storm sewer design . • Design Storm Frequency Storm culverts Curb openings 3 25 -year storm event 10 and 100-year stom1 events • Runoff Coefficients Grass and wooded areas Commercial areas Impervious surfaces c = 0.30 c = 0.75 c = 0.90 • Rainfall Intensity equations and va lu es for Brazos Co unt y can be found in Table 1. • Time of Concent ration , tc -Calc ul ations fo r are based on th e method found in the TR- 55 publication . Refer to Appendix A for the equat ions and calculations. The drainage runoff flow paths used for calculating the times of concentration for each drainage are shown in Exhibit A. STORM WATER RUNOFF DETE RMINATION The peak runoff valu es were determined in accordance wi th the criteria presented in the previous section for the 10 and 100-year storm events. Th e runoff coefficients are based on the development of this tract. The drainage areas are shown in Exhib it A. Runoff condit ion s are summarized in Tab le 1. The time of concentration equations are shown in Table 2. TABLE 1 -Rainfall Intensity & Runoff Data Area c 5 year storm le 10 year storm 25 year storm 50 year storm Area # (acres) A , A2 A, Total 1 0 .63 1 .52 2 .75 4 .90 -·---------- 2 1 .36 0 .84 0 .00 2.20 The Rat i onal Method : Q=CIA Q = Flow (cfs) A = Area (acres) C = Runoff Coeff. I = Rainfall Intens ity (in/hr) Brazos County: 5 year storm b = 76 d = 8 .5 10 yea r storm b = 80 d = 8.5 c, C2 c, Crotal Is (min) (in/hr) 0 .9 0 .75 0 .3 0 .52 24.2 4 .92 --------- 0 .9 0 .75 0 .3 0 .84 11 .2 7 .3 2 I = b I (tc+d)0 le= Time of concentration (mi n) tc = L/(V*60) L = Length (ft V =Velocity (ft/sec) 5 year storm b = 89 d = 8.5 50 year sto rm b = 98 d = 8 .5 Os (cfs) 12.46 -- 13.58 110 a,o l 2s (in/hr) (cfs) (in/hr) 5 .59 14.16 6 .4 2 8 .23 15.26 9 .41 100 yea r s torm b = 96 d = 8 .0 e = 0 .79 e = 0 .76 e = 0.75 e = 0 .745 e = 0 .7 30 (Data taken from State Department of Highways and Public Transportation Hydraulic Manual. page 2-16) TABLE 2 -Time of Concentration (tc) Equations 0 2s l so (cfs) (in/hr) 16.25 7 .29 -- 17.44 10 .64 The time of concentration was determined usin g methods found in TR-55 , "Urban Hydrology for Small Wat ersheds ." Th e equation s are as follows: Time of Concentration : 4 Tc = T t(shcet n ow)+ T t(concentrated sheet n ow) where: T 1 =Travel Time , minutes Oso (cfs) 18.47 -- 19.72 100 year storm 1100 0 100 (in/hr) (cfs) 7 .61 19 .28 ----- 11 .10 20 .59 For Sheet Flow: For Shallow Concentrated Flow: w here : Ti = travel time, hours n =Mannin g's roughne ss coefficient L = flow len gt h , feet P 2 = 2-year, 24 -h o ur rainfall = 4.5" s = land slope , ft /ft T 1 =LI (60 *V) w here : Ti = travel time, minutes V =Velocity , fps (See Fig 3 -1 , App . E) L = flow length, feet Refer to Appendix A for calculations. STORM SEWER CULVERT DESIGN A storm sewer culvert is proposed at the driveway for this development. This culvert will be designed for the 25-year stonn event, and it will also pass the 100-year storm event without overtopping the driveway. Refer to Appendix A for the culvert calculator data sheets for the 25-and 100-year stonn events. STORM RUNOFF DESIGN CALCULATIONS As previously stated, the stonn water runoff from this site will flow directly into the No1ih Fork of Lick Creek. The runoff from this site will increase due to the building and parkin g lot construction. The parking lot will have a curb opening to allow the runoff to exit the pavement area. A maximum depth of 1 O" for the 100-year storm event was selected to size the openings. The following calculations wi ll show that the depth of the water at the curb opening does not exceed 10 inches for the 100-year storm event. Capacity of curb openings solving Weir Flow Equation: Q = 3 * L * y12 Where: Q = flow at inlet , cfs L = length of inlet opening, feet y = total depth of flow on inlet, feet For 1-3 .5 ' opening flowing -4 " deep (y =0 .333'), Q=2.02 cfs 5" deep (y=0.417'), Q=2.83 cfs 6" deep (y = 0 .500 '), Q = 3 .71 cfs 7" deep (y = 0.583 '), Q = 4.67 cfs 7 .5" deep (y = 0.625 '), Q = 5 .19 cfs 8" deep (y = 0.667'), Q = 5 .72 cfs 8.5'' deep (y = 0.708 '), Q = 6 .2 6 cfs 9" deep (y = 0.750 '), Q = 6.82 cfs For 1-2 ' divider with water flowing over it 's top - 1" deep (y = 0 .083 '), Q = 0 .14 cfs 1.5'' deep (y = 0 .125 '), Q = 0 .2 7 cfs 5 2 " deep (y = 0.167'), Q = 0.41 cfs 2.5 " deep (y = 0.208 '), Q = 0.57 cfs 3 " d eep (y = 0.2 50 '), Q = 0 .75 cfs 4 " deep (y = 0 .3 33 '), Q = 1.15 cfs For C urb Opening : [3-3 .5 ' openings with 2-2 ' dividers ] Tota l flow going thru Curb Opening -Q10 = 15.26 cfs Q100 = 20.59 cfs D et ermine d epth of flow for Q10 by trial and error : For 8" deep: (3 openings* 5 .72 cfs/opening) + (2 dividers * 0.41 cfs) = 17.98 cfs 17 .98 > 15 .26 =>flows less than 8" deep For 7 " d e ep : (3 * 4.67 cfs) + (2 * 0.14 cfs) = 14 .29 cfs 14.29 < 15 .26 =>flows deeper than 7 " For 7.5 " deep : (3 * 5 .19 cfs) + (2 * 0.27 cfs) = 16.11 cfs 16.11 >15.26 =>flows Jess than 7.5 " deep For Q10 , the flow thru the Curb Opening is between 7" and 7.5" deep. D et ermine depth of flow for Q 100 by trial and error: For 8.5'' deep: (3 openings* 6.26 cfs/opening) + (2 dividers* 0.57 cfs) = 19 .92 cfs 19.92 < 20.59 =>flows deeper than 8.5'' For 9" dee p: (3 * 6 .82 cfs) + (2 * 0 .75 cfs) = 21.96 cfs 21.96 > 20.59 =>flows less than 9 " deep For Q 100 , the flow thru the Curb Opening is between 8.5" and 9" deep. CONCLUSIONS The construction of this project will increase the storm w ater runoff from this site. Howev er, the runoff will be carried through the parking area to an existing drainage and immediately into the 100-year floodplain. The increased flow in this tributary should not have a significant impact on the surrounding property. No flood damage to downstream or adjacent landowners is expected as a result of this development. 6 APPENDIX A Calculations 7 Proposed 27 " Culvert -25 Year Storm Culv ert Calculat or Entered Data: Shape ............. . Number of Barrels .. Solving for .......... . Chart Number .... . Scale Number . . . . . . ..... . Chart Description .............. . Scale Description .............. . Overtopping ................... . Flowrate .................. . Manning's n .................. . Roadway Elevation ............ . Inlet Elevation .............. . Outlet Elevation ............. . Diameter ..................... . Length ....................... . Entrance Loss ................ . Tailwater .................... . Computed Results: Headwater ...................... . Slope ... · ....................... . Veloci t y ....................... . Circular 1 Headwater 1 3 CONCRETE PIPE CULVERT; NO BEVELED RING ENTRAN CE GROOVE END ENTRANCE, PIPE PROJECT I NG FROM FILL Off 16.2500 cfs 0. 0140 284.0000 ft 281.2700 ft 281.0000 ft 27.0000 in 54 .0000 ft 0.0000 2.2500 ft 283.6812 ft Outlet Control 0.0050 ft/ft 4.0869 fps Proposed 27 " Culvert -100 Year Storm Culvert Calculator Entered Data: Shape ................ . Number of Barrels .... . Solving for .......... . Chart Number .......... . Scale Number . . . . . . . . . . . . .... . Chart Description . . . . . . . .... . Scale Description ......... . Overtopping ............... . Flowrate .................. . Manning's n ............... . Roadway Elevation .............. . Inlet Elevat ion ................ . Outlet Elevation ... . Diameter ........... . Length ................ . Entrance Loss . Tailwater ..... Computed Results: Headwater .... . Slope ........ . Velocity ..... . Aggieland Fitness Center College Station, Texas Circular 1 Headwater 1 3 CO NCRE TE P I PE CULVER T ; NO BEVE LE D RI NG ENTRAN CE GROOVE END ENTRANCE, PIPE PROJECTING FROM F I LL Off 19.2800 cfs 0. 0140 284.0000 ft 281.2700 ft 281.0000 ft 27.0000 in 54.0000 ft 0.0000 2.2500 ft 283 .85 69 ft Outlet Control 0.0050 ft/ft 4.8490 fps Sh ee t Flo w: Time of Concentration Calculations Drainage Area #1 Flow length = 185 ' = L Slope = 1.1 % n = 0.15 , sho1i grass prairie P 2 = 4 .5" T 1 = 0.007 (0 .15 * 185)0 8 (4.5)05 (0 .011)04 = 0.286 hours = 17 .2 minutes Shallo w Concentrated Flow : Flow length = 295 ' = L Slope = 1.2% For unpaved surface at 1.2%, Velocity (V) = 1.7 fps (see Fig . 3-1) ~ = 295 ' I (60*1.7) = 2 .9 minutes F low through Ditch #1: F low through existing 24 " RCP: Flow through Ditch #2 : (Refer to attached channel calculations) V-bottom ditch with 1 :4 side s, F low length = 167' = L Slope = 0.76% (Note: slope & length obtained from old plans.) n = 0.035 Area, A = approximately 1 acre Q5 = 3.9 cfs (using tc = 20 .1minutes,C =0 .75) From Manning 's data , Velocity, V = 1.8 fps ti = 92 .8 sec = 1.5 minutes (Refer to attached culvert calculations) 24" RCP, Flow length = 90 ' = L Slope= 0.5% n = 0.014 Area, A = approximately 2 acres Q 5 = 7 .8 cfs (using tc = 22 .2 minutes, C = 0.75) From Manning 's data, Velocity, V = 2 .5 fps t1 = 36.0 sec = 0.6 minutes (Refer to attached channel calculations) V-bottom ditch with 1 :5 sides , Flow length = 260 ' = L Slope= 0 .72% (Note: slope & length obtained from old plans .) n = 0.035 Area, A = approximately 3 acres Q 5 = 11.1 cfs (using tc = 24 .2 minutes , C = 0.75) From Manning 's data, Velocity, V = 2.2 fps ti= 118 .0 sec = 2 .0 minutes T c= 17.2+2 .9+ 1.5 +0.6+2.0 = 24.2 minutes Sh ee t Flow: Time of Concentration Calculations Drainage Area #2 F low length = 100 ' = L Slope = 2% n = 0 .15 , s ho1t gra ss pra irie P2 = 4.5 " T 1 =0.007 (0.15 * 100)08 (4.5)0.5 (0.02)04 = 0.13 8 hours= 8.3 minutes Flow along Pavement Segment #1: F low length = 17 8' = L S lope = 3 % For pave d s urface at 3%, Veloc ity V =3.5 fps (see Fig . 3-1) = 178 ' I (60*3.5) = 0.8 minutes Flow along Pavement Segm ent #2: Flow length = 270 ' = L S lope = 1.1 % For paved surface at 1.1 %, Velocity V =2 .15 fps (Fig 3-1) = 270 ' I (60*2.15) = 2 .1 minutes Tc= 8.3 + 0 .8 + 2.1 = 11.2 minutes Data for Drainage Area #1 Tc Calculations Flow Path Area Segment (acres) Ditch #1 1 Exist. 24" RCP 2 Ditch #2 3 The Rational Method : Q=CIA Q = Flow (cfs) A =Area (acres) C = Runoff Coeff. I = Rainfall Intensity (in/hr) Brazos County: 5 year storm b = 76 d = 8 .5 e = 0 .785 c 0 .75 0 .75 0 .75 le 5 year storm Is Os (mi n) (in /hr) (cfs) 21 .6 5 .250 3.94 -- 22 .2 5 .169 7 .75 24 .2 4 .919 11 .07 I = b I (tc+d)e tc = Time of concen tr ation (min) tc = L/(V*60) L = Length (ft V = Velocity (fUsec) .µ <+--.µ <+- C1J a.. 0 VI C1J VI s.. ::I 0 u s.. CV ..., "" 3: 3-2 .50 .20 - .10 - .06 .04 . 02 - .01 - .005 I 1 j ' I ' I I , , , , , ; J J 0 .:.."'L~o, ~ q, ~~ ,li I I I I J f 2 ; I , I 4 t j I ,, i I I I . I 6 ' I ' ' ' I Average velocity, ft/sec J .· . . I I I I ,, I I 10 . I I Fiicu"' :J -1.-Av~ralC~ ·~lociti~~ for c•limatinJC lrJvcl tim~ for "hallow conc~nlral~d now . (210 -Vl-TR -55. Second Ed ., June L98Gl I 20 Ditch #1 -5 Year Storm Time of Concentration Calculations Channel Calculator Given Input Data : Shape .......................... . Solving for .................... . Flowrate ....................... . Slope .......................... . Manning's n .................... . Height ......................... . Bottom width ................... . Left slope ..................... . Right slope .................... . Computed Res u lts: Depth .......................... . Velocity ....................... . Full Flowrate .................. . Flow area ...................... . Flow perimeter ................. . Hy draulic radius ............... . Top wi d th ...................... . Area ........................... . Perimeter ...................... . Percent full ................... . Agg ieland Fitness Center College Station , Texas Trapezoidal Depth of Flow 3.9000 cfs 0.0076 ft /ft 0 .035 0 20.0000 in 0 .0000 in 0.2500 ft/ft (V/H) 0.2500 ft/ft (V/H) 8.7191 in 1 .8468 fps 35 .6 904 cfs 2.11 18 ft2 71.8997 in 4.2294 in 69.7529 in 11 . 1111 ft2 164.9242 in 43 .5956 % Existing 24" Pipe -5 Year S t orm Time of Concentration Calculations Culvert Calculator Entered Data: Shape ........... . Number of Barrels So l vi ng f or . . ....... . Chart Num ber ......... . Scale Number ......... . Chart Description .... . Scale Description .... . Over topping .......... . Flowrat e ............. . Manning 's n .......... . Roadway Elev ation .... . Inlet El eva t ion ..... . Outlet Elev ation .... . Diameter .......... . Length ............ . Entrance Loss .. . Tailwat er ...... . Computed Res u lts: Headwa t er ......... . Slope ............. . Velocity .......... . Aggi eland Fitness Ce n ter Co l lege Station, Texas Circular 1 Headwater 1 3 CONCRETE PIPE CULVERT; NO BEVELED RI NG ENTRAN CE GROO VE END ENTRAN CE, PIPE PROJEC TING FRO M FILL Off 7.8000 cfs 0.0140 288.0000 ft 283.7300 ft 283.2800 ft 24.0000 in 90.0000 ft 0.0000 2.0000 ft 285.4993 ft Outlet Control 0.0050 ft /ft 2.4828 fps Ditch #2 -5 Year Storm T ime of Concentration Calculat i ons Channel Calculator Given Input Data: Shape .......................... . Solving for .................... . Flowrate ....................... . Slope .......................... . Manning' s n .................... . Height ......................... . Bottom wi dt h ................... . Left slope ..................... . Right slope .................... . Computed Res u l t s: Depth .......................... . Velocity ....................... . Full Flowrate .................. . Flow area ...................... . Flow perimeter ................. . Hydraulic radius ............... . Top wi dth ...................... . Area ........................... · Perimeter ...................... . Percent full ................... . Aggieland Fitness Center College Station, Texas Trapezoidal Depth of Flow 11.1000 cfs 0.0072 ft/ft 0.0350 20.0000 in 0 .0000 in 0 .2000 ft/ft (V/H) 0 .2000 ft/ft (V/H) 11.9597 in 2.2350 fps 43.7340 cfs 4. 9664 f t 2 121.9651 in 5.8637 in 119. 5966 i n 13.8889 ft2 203.9608 in 59.7983 % EXHIBIT A Drainage Area Map 16