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HomeMy WebLinkAboutRAFFERTY'S PUD - PRELIMINARY - 17-95 - SUBMITTAL DOCUMENTS - ROUND 2 - DRAINAGE REPORTDIY CAN aRM APAilPOn I I AP7 0 U----- -- , -- I _ = aorrnrd . rxrr�w �aav ppavWavowx - Q I ,, nurMX 1._. lIITOIplLN!!R I TmaMa mo I Imm \\" \ 11.- +Nlnw �.w pm a t) I mod.AWM 7�r -- aaPAM i ; !i!i!i!!il�!■ ! \ �� 19 1 w 111 1 H I 1 1. 1 Q - � \ .. a fi , PHASE I VONME nmw ALCM \ 7 iA I 2 A,i f l I I i 4111 ! r! rlv ,-WOW - I "A. - I � I I I I! I1111 -- SITE PLAN 6GOl.E �p•IOm'�' SITE MAP - I WALTER DAVIDSON & ASSOCIATES .-, Consulting Engineers & Surveyors ############ NORMAL & CRITICAL. DEPTHS FOR A TRAPAZOIDAL CHANNEL ############# I .I $$$$ INPUT DATA $$$$ DISCHARGE 1 CFS SLOPE = 0.01000 LEFT SIDE SLOPE = 3.0 = 0.39 FT NORMAL DEPTH rl CRITICAL DEPTH = 0.22 FEET wl MANNING'S N = 0.060 BASE WIDTH = 1.0 FT RIGHT SIDE SLOPE = 3.0 NORMAL VELOCITY = 0.96 FPS CRITICAL VELOCITY = 2.23 FPS WALTER DAVIDSON & ASSOCIATES Consulting Engineers & Surveyors PRELIMINARY DRAINAGE REPORT RAFFERTrS BOARDWALK AVE. FORT COLLINS, CO. March 27, 1995 DETENTION OUTFACE DITCH CALCULATIONS page 6 z Aavac� t a: n3...tk it i Hari St( v,e z.r�b��.vfH+�e� wx I ��d4'ia �u Fy.''S✓ al "� ot. s } t faN � 1 v t LtA h'✓'I -T l..ttr! tat. 2 KM^�r a«�y 1� t W .�g�� a',.S �s� 1 _ J r ws '- I v 'A w WALTER DAVIDSON & ASSOCIATES'ry I'T/' SSA i - JpYpO Consulting Engineers & Suiveyors - rl PRELIMINARY DRAINAGE REPORT .,'� M� - a � RAFFTY ER'S ; 14 r f r s rf ` BOA El i 4 t r J t I-ORI LULLINb, Jt '=IT, 1 tWiy 3' 1995;1`4 It {AA iTq': n[r >,,, tk I&arl 15�"t !r{rw.fi i :i 5ydtf Ai)r t'�5 t,t t•1"cj�tr ah�tt lFy v ka 515 F '.11IT ! y,,�.}.e.e M.� r!k W f. ,yr Mr• �l �< mi I W $r 1 FA �lt fr� atl i,M ° r trY ft.' �w A 5 ( a N G fS 0 1 Y ilF'^�Sii JAI !i*thX' ty,., CIS 1Y.'{ fjt a�4:. :f �{CsAJy Y'l! 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YEAR MONTH , J I F I M I A I M I J I J I A( S I 0 I N I D ---------------------------- I -----------------------------------------------------------I OVERLOT GRADING I I I _ I WIND EROSION CONTROL I I Soil Roughing Perimeter Barrier I I Additional Barriers I Vegetative Methods + I Soil Sealant Other I I RAINFALL EROSION CONTROL STRUCTURAL: Sediment Trap/Basin Inlet Filters Straw Barriers Silt Fence Barriers Sand Bags Bare Soil Preparation Contour Furrows Terracing Asphalt/Concrete Paving Other VEGETATIVE: Permanent Seed Planting) Mulching/Sealant Temporary Seed Planting) Sod Installation Nettings/Mats/Blankets Other STRUCTURES: INSTALLED BY MAINTAINED BY VEGETATION/MULCHING CONTRACTOR DATE SUBMITTED APPROVED BY CITY OF FORT COLLINS ON HDI/SF-C:1989 EFFECTIVENESS CALCULATIONS ----------------- ---- -------------- ------ ------- ----- ---- -------------1 PROJECT: Rafferty's - Boardwalk STANDARD FORM B COMPLETED BY: Walter Davidson DATE: 3-27-95 I .Erosion Control C-Factor P-Factor Method Value Value Comment ---------------------------------------------------------- Bare Soil 1.0 1.0 Smooth Condition Sediment Trap 1.0 0.5 Roads & Walk 0.01 -1.0 Hay Mulch 0.06 1.0 Slit Fence 1.0 0.50 Established Grass 0.08 1.0 ---------------- MAJORI PS SUB I AREA ------------- BASINS (A) IBASINI (Ac) CALCULATIONS ----- A1 ------ 79.4 ----- A ------ 2.89 ------------------------------------------- Parking & Blgd = 1.67ac Mulch = 2.89-1.67= 1.22ac WTO C Factor = (1.0x1.67+0.06x1.22 = 1.74/2.89 = 0.602 WTO P Factor = Trap Fence 0.5 x 0.5 = 0.25 l EFF = (1-(CXP))XlOO= I I I = (1-(0.602xO.25)x100) 79.4 / cK --------------------- I/SF-B:1989 12.89 RAINFALL PERFORMANCE STANDARD EVALUATION ------------------------------------------------------- ------------- PROJECT: Rafferty's - Boardwalk STANDARD FORM A COMPLETED BY: Walter Davidson DATE: 3-27-95 --------------------------------------------------------------------- DEVELOPEDIERODIBILITY1 Asb Lsb Ssb Lb I Sb I PS SUBBASIN�--- ZONEI (ac) (ft) (%) . (feet) I (%) I (%) ----- -------------- ------- 1------- I ------- I ------- A Moderate 12.89 1494 1 1.3 1494 1 1.3 179.4 --------------------------------------------------- DI/SF-A:1939 WALTER DAVIDSON &" ASSOCIATES k :i �_j,Consulting Engineers & Surpveyors d r a a ;i °n•tg',>S[y,$Fµ`.•,,..,N ,,.u". .d�'�,'Hi>c. >t r. *Tr .. £'{L'y.. 3 PRELIMINARY DRAINAGE REPORT-1 RAFFERTY'S BOARDWALK AVE.a FORT COLLINS, CO. May 3, 1995 vq �!+`3:� rµ`6 i,i .;, .. '. '�• � I ! > �: 91 Y•i r r..fz3 f +Nw IN11 s ..w 44 11 eG +up'r�i M 1 is v k rr 5 III �d .. 2. ) i �"^r ijt¢R y y u Vk 1 I bt �y 1 EAR Y- jv .ws > qVr 'C` aJ4 s i %Ag � AI IVY H _ ... rt..idfly:�� + l i t � � V 1 r �. ti• U PRELIMINARY EROSION CONTROL CALCULATIONS I Data for RAFFERTY'S revised Prepared by WALTER DAVIDSON & ASSOCIATES 2 May 95 HydroCAD 3 01 000574 (c) 1986-1991 Applied Microcomputer Systems 3 O J POND 2 18 17 16 15 14 13 12 10 9 8 7 6 5 4 3 2 POND 2 INFLOW & OUTFLL.._ LOWER BASIN N d' LD STOR-IND METHOD E K ELEU- 4997.7 FT P AK STOR= 31777 CF gin= 18.0 CFS gout= 1.7 CFS LAG= 87.1 MIN M m N d �D m m N73- 0 m N CV CV CV N m m m m m TIME (hour5) LOWER BASIN OUTFLOW PEAK= 1.7 CFS @ 13.88 HOURS HOUR 0.00 18 36 54 .72 .90 1.08 1.26 1.44 1.62 11.00 I 0.0 0.0 .2 .5 .6 .7 .9 1.1 1.4 1.6 12.80 1.6 1.7 1.7 1.7 1.7 1.7 1.7 Data for RAFFERTY'S revised Prepared by WALTER DAVIDSON & ASSOCIATES 2 May 95 HydroCAD 3 01 000574 (c) 1986-1991 Applied Microcomputer Systems POND 2 DISCHARGE LOWER BASIN flood elev. ---------------------- — 4999.6 4999.1 4998.6 4998.1 BROAD -CRESTED RECTANGULAR WEIR z 4997. 6 CD 4997.1 Q 4996. 6 w 4996.1 w 4995.E 4995.1 .7` x .3' ORIFICE 4994.6m �n m in m Ln m in m n I I N N m f'7 I- ,I - DISCHARGE (cfs) Data for RAFFERTY'S revised Prepared by WALTER DAVIDSON & ASSOCIATES 2 May 95 HydroCAD 3 01 000574 (c) 1986-1991 Applied Microcomputer Systems POND 2 LOWER BASIN STARTING ELEV= 4994.6 FT FLOOD ELEV= 5000.0 FT 3 x FINER ROUTING ELEVATION AREA INC.STOR CUM.STOR (FT) (SF) (CF) (CF) 4994.6 0 0 0 4995.0 5101 1020 1020 4996.0 9562 7332 8352 4997.0 14126 11844 20196 4998.0 19000 16563 36759 5000.0 20000 39000 75759 STOR-IND METHOD PEAK ELEVATION= 4997.7 FT PEAK STORAGE = 31777 CF Qin = 18.0 CFS @ 12.43 HRS Qout= 1.7 CFS @ 13.88 HRS ATTEN= 90 o LAG= 87.1 MIN IN/OUT= 1.02 / .28 AF INVERT (FT) OUTLET DEVICES 4994.6 .7' x .3' ORIFICE Q=.6 Width 2/3 SQR(2g) (HAl.5 - [H-Height]^1.5) 4997.8 4' BROAD -CRESTED RECTANGULAR WEIR Q=C L HAl.5 C=2.82, 3.6, 3.6, 0, 01 0, 0, 0 TOTAL DISCHARGE vs ELEVATION FEET 0.0 .1 .2 .3 .4 .5 .6 .7 .8 .9 4994.6 0.0 .1 .2 .4 .5 .6 .7 .7 .8 .9 4995.6 .9 1.0 1.0 1.1 1.1 1.2 1.2 1.3 1.3 1.3 4996.6 1.4 1.4 1.4 1.5 1.5 1.5 1.6 1.6 1.6 1.7 4997.6 1.7 1.7 1.8 2.2 2.8 3.7 4.7 5.9 7.5 9.3 4998.6 11.4 13.8 16.4 18.7 21.0 23.5 26.0 28.6 31.3 34.1 4999.6 37.0 40.0 43.0 46.1 49.3 Data for RAFFERTY'S revised Prepared by WALTER DAVIDSON & ASSOCIATES 2 May 95 HydroCAD 3 01 000574 (c) 1986-1991 Applied Microcomputer Systems 3 O J 24 22 20 18 16 14 12 10 S 6 4 2 POND 1 INFLOW & OUTFLOW UPPER DETENTION N d- 0 STOR-IND METHOD EAK ELEU= 5002 FT P AK STOR= 26106 CF Gin= 24.2 CFS Gout= 2.6 CFS LAG= 30.1 MIN M O N� O O m N� o O TIME (hours) POND 1 UPPER OUTFLOW PEAK= 2.6 CFS @ 12.93 HOURS HOUR 0.00 18 36 .54 .72 .90 1.08 1.26 1.44 1.62 11.00 I 0.0 .2 .6 .8 1.0 1.3 1.7 2.0 2.3 2.5 12.80 1 2.5 2.6 2.5 2.5 2.5 2.5 2.4 Data for RAFFERTY'S revised Prepared by WALTER DAVIDSON & ASSOCIATES 2 May 95 HydroCAD 3 01 000574 (c) 1986-1991 Applied Microcomputer Systems 5001.5 5001.0 5000.5 0 5000.0 4999.5 4999.0 J 4998.5 ZEE�M 4997.5L 4997 . 0m POND 1 DISCHARGE UPPER DETENTION flood elev. 3' BROAD- `S4T RECTANGULAR WEIR -----�---------------- 1 1 1 1 1 . q/ XI N m V- m 0 r'- DISCHARGE (cfs) 31/ ORIFICE OD M m Data for RAFFERTY'S revised Prepared by WALTER DAVIDSON & ASSOCIATES 2 May 95 HydroCAD 3 01 000574 (c) 1986-1991 Applied Microcomputer Systems POND 1 UPPER STARTING ELEV= 4997.0 FT FLOOD ELEV= 5003.0 FT 3 x FINER ROUTING ELEVATION AREA INC.STOR CUM.STOR (FT) (SF) (CF) (CF) 4997.0 0 0 0 4999.0 900 900 900 5000.0 5494 3197 4097 5001.0 11390 8442 12539 5002.0 14827 13109 25647 5003.0 18000 16414 42061 STOR-IND METHOD PEAK ELEVATION= 5002.0 FT PEAK STORAGE = 26106 CF Qin = 24.2 CFS @ 12.43 HRS Qout= 2.6 CFS @ 12.93 HRS ATTEN= 89 % LAG= 30.1 MIN IN/OUT= .88 / .44 AF INVERT (FT) OUTLET DEVICES 4997.0 .8' x .3' ORIFICE Q=.6 Width 2/3 SQR(2g) (HAl.5 - [H-Height]^1.5) 5002.1 3' BROAD -CRESTED RECTANGULAR WEIR Q=C L H^1.5 C=2.82, 3.2, 0, 0, 0, 0, 0, 0 FEET 4997.0 4998.0 4999.0 5000.0 5001.0 5002.0 5003.0 TOTAL DISCHARGE vs ELEVATION 0.0 .1 .2 .3 .4 .5 .6 .7 .8 .9 0.0 .1 .2 .4 .6 .7 .8 .9 .9 1.0 1.1 1.1 1.2 1.2 1.3 1.3 1.4 1.4 1.5 1.5 1.6 1.6 1.7 1.7 1.7 1.8 1.8 1.8 1.9 1.9 1.9 2.0 2.0 2.0 2.1 2.1 2.1 2.2 2.2 2.2 2.3 2.3 2.3 2.4 2.4 2.4 2.4 2.5 2.5 2.5 2.5 2.6 2.9 3.4 4.0 4.8 5.7 6.8 8.0 9.3 10.8 Sheet3 CALCULATE RUNOFF HYDROGRAPH FOR DETENTION LOWER BASIN C= DRAIN AREA 2.68 AC JIN/HR TOTAL DELTA INC. INTENSITY ARRANGED DISCHARGE TIME MIN RAIN RAIN IN/HR INTENSITY CFS TIME MIN 0 0 0 0 0.00 0.0 0 11 . 1.26 1.26 6.85 0.11 0.3 11 22 5 1.83 0.58 3.15 0.19 0.4 22 33 3.95 2.17 0.34 1.85 0.25 0.6 33 44 3.3 2.42 0.25 1.35 0.34 0.8 44 55 2.88 2.64 0.22 1.20 0.50 1.1 55 66 2.4 2.64 0.00 0.00 1.35 3.1 66 77 2.1 2.70 0.06 0.30 3.15 7.2 77 88 1.9 2.79 0.09 0.50 6.85 15.6 88 99 1.71 2.82 0.03 0.19 1.85 4.2 99 110 1.55 2.84 0.02 0.11 1.20 2.7 110 121 1.44 2.90 0.06 0.34 0.45 1.0 121 132 1.33 2.93 0.02 0.12 0.30 0.7 132 143 1.23 2.93 0.01 0.03 0.12 0.3 143 154 1.15 2.95 0.02 0.11 0.11 0.3 154 165 1.09 3.00 0.05 0.25 0.03 0.1 165 176 1.05 3.08 0.08 0.45 0.00 0.0 176 Page 1 PRELIMINARY DRAINAGE REPORT RAFFERTYS FORT COLLINS, CO. CALCULATE RUNOFF HYDROGRAPH FOR DETENTION UPPER BASIN C= 0.85 DRAIN AREA 4.14 AC TOTAL DELTA INC. INTENSM ARRANGED DISCHARGE TIME MIN i INMR RAIN RAIN IN/HR INTENSITY CFS TIME MIN 0 0 0 0 0 0.00 0.0 0 11 6.85 1.26 1.26 6.85 0.11 0.4 11 22 5 1.83 0.58 3.15 0.19 0.7 22 33 3.95 2.17 0.34 1.85 0.25 0.9 33 44 3.3 2.42 0.25 1.35 0.34 1.2 44 55 2.88 2.64 0.22 1.20 0.50 1.8 55 66 2.4 2.64 0.00 0.00 1.35 4.8 66 77 2.1 2.70 0.06 0.30 3.15 11.1 77 88 1.9 2.79 0.09 0.50 6.85 24.1 88 99 1.71 2.82 0.03 0.19 1.85 6.5 99 110 1.55 2.84 0.02 0.11 1.20 4.2 110 121 1.44 2.90 0.06 0.34 0.45 1.6 121 132 1.33 2.93 0.02 0.12 0.30 1.1 132 143 1.23 2.93 0.01 0.03 0.12 0.4 143 154 1.15 2.95 0.02 0.11 0.11 0.4 154 165 1.09 3.00 0.05 0.25 0.03 0.1 165 176 1.05 3.08 0.08 0.45 0.00 0.0 176 Page 1 PRELIMINARY DRAINAGE STUDY RAFFERTY'S FORT COLLINS, CO. PREDEVELOPED RUNOFF TOTAL AREA DESIGN STORM 2 YR DRAINAGE AREA 6.83 AC LAND USE UNDEVELOPED FLOW LENGTH = D SLOPE OF BASIN Tc = (FROM FIG. 3-2) _ 2YEAR INTENSITY 1.38 IN/HR Q2YR=CiA 1.9 CFS PREDEVELOPED RUNOFF UPPER AREA DESIGN STORM 2 YR DRAINAGE AREA 4.14 AC LAND USE UNDEVELOPED FLOW LENGTH = D SLOPE OF BASIN Tc = (FROM FIG. 3-2) _ 2YEAR INTENSITY 1.38 IN/HR Q2YR=CIA 1.1 CFS RATIONAL C 0.20 500 FEET 1.30% 33.0 MIN RATIONAL C 0.20 500 FEET 1.30% 33.0 MIN PREDEVELOPED RUNOFF LOWER AREA DESIGN STORM 2 YR DRAINAGE AREA 2.68 AC LAND USE UNDEVELOPED RATIONAL C 0.20 FLOW LENGTH = D 500 FEET SLOPE OF BASIN 1.30% Tc = (FROM FIG. 3-2) = 33.0 MIN 2YEAR INTENSITY 1.38 IN/HR Q2YR=CiA 0.7 CFS DRAIN.XLS Page 1 5/2/95 No Text No Text WALTER DAVIDSON & ASSOCIATES-' PRELIMINARY DETENTION CALCULATIONS WALTER DAVIDSON & ASSOCIATES Consuiting Engineers & Surveyors PRELIMINARY DRAINAGE REPORT.'".".__.•;,. RAFFER.TYS BOARDWALK AVE. FORT COLLINS, CO: May 3, 1995 e. RAINFALL EROSION" This site has a moderate ralnfall'erosion potential. In order to comply with the City, of Fort Collins Dramage;Cntena the following measures will be provided. 1 Prior to oyerlot grading the detention.basinwill be excavated to provide _._ .. proper voldme to:serve as'an sediment trap, This vAlI be maintained in _ .. r.. . - . accordance.with City cntenauntil the entire site is stabilized 2: Silt ,Ferices will .be installed around the downstream perimeter, of the „ site and through the graded portions of thesite throughout the development phase as necessary to -obtain the.necessary erosion control effectiveness......__ 3. Straw Bale ditch'chedcs,will be'provided as indicated around inlets and in the ditch1mes .''^ SY Re 2 +y �i r't`•ttm 91^'.f l.Y u rv. 1 u; fu:,, Final`details of the erosion control plan will be. developed and provided 4 concurrent"with the final site plans j '' -- WALTER DAVIDSON & ASSOCIATES Consuling Engineers & Surveyors VZ n PRELIMINARY DRAINAGE REPORT RAFFERTrS BOARDWALK AVE. FORT°COLLINS, CO. May 3, 1995 8. MASTER PLANNED FACILITIES: No master planned facilities are proposed for this property 9. COMPLIANCE WITH MASTER DRAINAGE PLAN: This project as proposed will comply with the master drainage plan for the McClellands/Mail Creek watershed. 10. IMPACTS ON RECEIVING WATERS: This project provides for sufficient storm water detention to mitigate all impacts on downstream receiving streams. 11. IMPACTS ON IRRIGATION DITCHES: There are no irrigation ditch in the vacinity of this project that might be - -- impacted by its development. - 12. EROSION CONTROL: WIND EROSION This site is in an area of moderate wind erosion hazard and wind barriers will be required at a maximum spacing of 200 feet. Wind barriers will be set in a southwest to northeast direction. Details of wind erosion control barriers will be furnished with final design. ' WALTER DAVIDSON & ASSOCIATES Consulting Engineers & Surveyors _ PRELIMINARY DRAINAGE REPORT RAFFERTYS BOARDWALK AVE. FORT COLLINS, CO. May 3, 1995 4. DESCRIPTION OF, PROPOSED DRAINAGE CONDITIONS: The development,plan for the Rafferty's site involves the construction of an 6,623 square foot restaurant with associated parking. An office development - is proposed for the northern portion of the site as Phase 2 development. The site plan provides for a landscape buffer along Harmony Road and Boardwalk; Ave. The site. will be allowed to sheet flow across the parking area to storm inlets: ._ located in a' curb along the southern edge of the parking lot. The storm water from these inlets will discharge directly into two detention basin incorporated In the landscape area along the eastern property line. The design. criteria for these detention basin are as follows TABLE 1 DETENTION BASIN DESIGN CRITERIA UPPER BASIN LOWER BASIN 1. Drainage area (Direct) 4.14 AC 2.68 AC I 2. Maximum release rate = 2 year pre -developed ---- 1.9cfs 3. MaDdmum surface area 14,827 sf 17537 sf 4. Maximum Depth 5.3 ft 3.1 ft 5. Maximum Storage 26106 cf 31,777 cf 6. Calculated release rate 2.6 cfs 1.7 cis 5. CONTRIBUTING UPSTREAM RUNOFF: No upstream flow enters the portion of the property proposed for development as this time. This is shown in the attached drainage area map (Exhibit 1). 6. IDENTIFICATION OF MAJOR DRAINAGE BASIN: This site lies within the McClellands/Mail Creek watershed 7. MASTER PLANNED CONDITIONS: . No master planned facilities are identified on this property. This property is planned to comply with the general requirement to limit the peak 100 year Post developed Storm release to the pre -developed 2 year storm release. WALTER DAVIDSON & ASSOCIATES Consulting Engineers & Surveyors PRELIMINARY DRAINAGE REPORT RAFFERTrS BOARDWALK AVE. FORT COLLINS, CO. May 3, 1995 FIGURE 1 N LOCATION MAP WALTER DAVIDSON & ASSOCIATES 1. STATEMENT OF COMPLIANCE,:P . This Drainage Report. has been developed in compliance with the /criteria setforth in the Storm Drainage Criteria Manual for the Cdy of Fort Collins. 41if L4'f f li 2. DELINEATION OF DRAINAGE BASIN; rt The drainage basin for this protect is shown in exhibit 1 attached hereto. The area covered by this report consist of the westem portion of total, tract shown on the attached plan since;no definite devetopment,plan or time schedule . for the eastern portion of the'property has been established'at this time 3: DESCRIPTION OF HISTORIC DRAINAGE CONDITIONS. " r This site is presently an undeveloped parcel of land located on the east side of Boardwalk Ave. between Harmony Road and Whalers Way, as shown in figure 1, in the McClellands/Mail Creek Master Plan area. This site has historically drained to the southeast comer. of the site generally in a sheet flow manner with a small swell along the southern property line. A 24 inch storm drain enter the northeast comer of the property near the intersection of Boardwalk and Whalers Way. This drain flows in an. open channel in a southerly direction along the right of way of Whalers Way to an existing 24' x 38" Storm drain through the residential property to the south. The 2 year peak discharge from the total site presently proposed for development is 1.9 cubic feet per second as calculated in the attached drainage calculations. I f 1 WMTER DAVIDSON & ASSOCIATES Consulting Engineers & Surveyors May 3,199 Mr. Glen D. Schluter- Stormwater Development Director City of Fort Collins Stormwater Utility; 235 Mathews Street' Fort Collins, CO 80522-0580 ,w h Re, Rafferty's Boardwalk Ave. ` WDA # 9509 ;. x Dear Mr Schlutter; 2i"' !J Enclosed for your approval are 2 copies of the revised Preliminary f Drainage .Report for the proposed. Rafferty's Restaurant on Boardwalk Ave. Also enclosed are `copies of the preliminarysite grading and utilities plan for this project This site is in the McClellands/Mail Creek Master Plan area; however, no Master Planned Facilities are proposed for this site. The master plan does not give any specific development standards for this site; therefore, the general criteria of limiting the 100 year post development runoff rate to the 2 year pre - development rate has been used. This Drainage Report has been developed in compliance with the /criteria setforth in the Storm Drainage Criteria Manual for the City of Fort Collins. If you have any questions, please feel free to contact me. Yours truly, WAD Walter H. Davidson, P. E. CO. Professional Engineer No. 30334 cc: Steve Maxwell 5127 MARC COURT • NASHVILLE, TN 37211 • (615) 331-2156 PRELIMINARY DRAINAGE REPORT RAFFERTY'S BOARDWALK AVE. FORT COLLINS, CO. May 3, 1995 PREPARED FOR: MAXWELL ARCHITECTS 631 SECOND AVE. SOUTH, SUITE 1F NASHVILLE, TENNESSEE 37210 PREPARED BY: WALTER DAVIDSON & ASSOCIATES CONSULTING ENGINEERS - SURVEYORS 5127 MARC COURT NASHVU i_F TENNESSEE 37211 PHONE 615-331-2156 t�yt161U[a�yl�l r� . G :r) o b, PRELIMINARY DRAINAGE REPORT RAFFERTY'S BOARDWALK AVE. FORT COLLINS, CO. May 3, 1995 PREPARED FOR: MAXWELL ARCHITECTS 531 SECOND AVE. SOUTH, SUITE 1F NASHVILLE, TENNESSEE 37210 PREPARED BY: WALTER DAVIDSON & ASSOCIATES CONSULTING ENGINEERS - SURVEYORS 5127 MARC COURT NASHVRIE, TENNESSEE 37211 PHONE 615-331-2156