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HomeMy WebLinkAboutDrainage Reports - 02/21/2008I 1 1 ' December 10, 2007 ' Mr. Basil Harridan City of Fort Collins Storm Water Utility ' 700 Wood Street Fort Collins, CO 80522 INTERWEST = CONSULTING G R O U P City of Ft. Collins Appro Plans Appmed By q_ Date Z/ z� / os Re: Habitat for Humanity — Rigden Farm Filing Six Lots M3, M4 & D14 ICG Project No. 1034-025-02 Dear Basil, Please accept the following letter report on behalf of Habitat for Humanity to demonstrate the site's compliance with the previously approved Final Drainage Report for Rigden Farm Filing Six, as prepared by JR Engineering, dated February 8, 2002. INTRODUCTION This proposed development is legally known as Lots M3, M4 & D14 of Rigden Farm Filing Six and contains a total of 49,806 square feet or 1.14 acres. Lot M3 is bounded on the north by William Neal Parkway, the east by Chase Drive, the south by Lot D14 and the west by an existing outlot. Lot M4 is bounded on the north by Tract AN, on the east by Chase Drive, and on the south and west by existing outlots. Lot D14 is bounded on the north by Lot M3, the east by Chase Drive, the south by Tract AN, and on the west by an existing outlot. The majority of the site generally drains to the northeast and flows are conveyed via curb and gutter and storm pipe system to existing detention pond 269. The design for this pond was included as part of the Filing Six Drainage Report and was constructed with that Filing. A small portion of the site drains to the north and flows are conveyed via curb and gutter and storm pipe system to existing water quality detention pond 3. The design for this pond was included as part of the Filing Six Drainage Report and was constructed with that Filing. The original runoff coefficient calculations used for the design of these ponds are attached for reference and all detention and water quality requirements for this site have been met by the overall Ridgen Farm development. EXISTING CONDITIONS ' The site is currently vacant and contains a stand of grasses. The Overall Drainage Basin Map that was included in the previously approved Final Drainage and Erosion Control Report shows the majority of the site draining into sub -basin 144, as shown on the enclosed map. A small 1 ' 1218 WEST ASH, SUITE C WINDSOR, COLORADO 80550 TEL. 970.674.3300 • FAX. 970.674.3303 1 1 1 1 1 1 Mr. Basil Hamdan December 10, 2007 Page 2 of 3 portion of the site, located in the northwest corner, drains into sub -basin 134. A small southern portion of the site drains into sub -basin 148. PROPOSED DEVELOPMENT The proposed development continues to direct runoff to the perimeter streets and ultimately to either the Foothills Regional Channel or the Fossil Creek Reservoir Inlet Ditch (FCRID) as anticipated in the Filing Six Final Drainage Report. The majority of the site will sheet flow north and east to Chase Drive where it will be conveyed by curb and gutter to the north to William Neal Parkway. Flows will then be conveyed east in the curb and gutter of William Neal Parkway to design point 42 of the Rigden Farm Filing Six report where it will be collected by an existing sump inlet and conveyed via storm pipe to Pond 269. Pond 269 releases to into FCRID. A small amount of the northwesterly portion of the site will sheet flow north toward William Neal Parkway and east via curb and gutter to an existing on -grade inlet with storm pipe system that conveys flows into Water Quality Detention Pond 3 before releasing into Foothills Regional Channel. A small amount of the south portion. of the site will sheet flow east toward Chase Drive where it will be conveyed by curb and gutter to the south to an existing on -grade inlet with storm system that ultimately conveys flows into Pond 269. The Filing Six design utilized an "Ultimate Development" condition for the basins that make up the site. All the area contained within the site was assumed to be Multi -Family with an imperviousness of at least 57% and a Runoff Coefficient of at least 0.64. The actual imperviousness of Lot M3 is 35%, with a minor storm Runoff Coefficient of 0.41. The actual imperviousness of Lot M4 is 33%, with a minor storm Runoff Coefficient of 0.39. The actual imperviousness of Lot D14 is 32%, with a minor storm Runoff Coefficient of 0.32. Therefore, it is requested that the site be deemed in substantial conformance with the previously approved Final Drainage Report. Please refer to the attached spreadsheet for calculations. EROSION CONTROL Erosion and sedimentation will be controlled on -site by use of silt fence, inlet protection; seeding and mulch. Please refer to the attached Grading and Erosion Control Plan. The measures are designed to limit the overall sediment yield increase due to construction as required by the City of Fort Collins. During overlot and final grading the soil will be roughened and furrowed perpendicular to the prevailing winds. During the performance of the work required by these specifications or any operations appurtenant thereto, whether on right-of-way provided by the City or elsewhere, the contractor shall furnish all labor, equipment, materials, and means required. The Contractor shall carry out proper efficient measures wherever and as necessary to reduce dust nuisance, and to prevent dust nuisance that has originated from his operations from damaging crops, orchards, cultivated fields, and dwellings, or causing naissance to persons. The Contractor will be held liable for any damage resulting from dust originating from his operations under these specifications on right- of-way or elsewhere. Mr. Basil Hamdan ' December 10, 2007 Page 3 of 3 ' It is unlawful to track or- cause to be tracked mud or other debris onto city streets or rights -of - way unless so approved by the Director of Engineering in writing. Wherever construction vehicles access routes or intersect paved public roads, previsions must be made to minimize the transport of sediment by runoff or vehicles tracking onto the paved surface. The contractor will be responsible for clearing mud tracked onto city streets on a daily basis. 1 t 1 1 All temporary and permanent erosion and sediment control practices must be maintained and repaired as needed to assure continued performance of their intended function. Silt fence may require periodic replacement. All disturbed areas must be seeded and mulched within 30 days of project start. Vegetation shall not be considered established until a ground cover is achieved which is demonstrated to be mature enough to control soil erosion to the satisfaction of the City Inspector and to survive severe weather condition. Please refer to the Erosion Control Cost Estimate for escrow amount attached to this letter. If you have any questions or comments please contact me at (970) 674-3300, east. 106. Sincerely, Robert Almirall, P.E. Colorado Professional Engineer 33441 ' Attachments 1 1 P�0 R..... :m :o 33441 -o Jr tol9tONAI-�_9� � o \ ) 20 10 0 20 40 SCALE: 1"= 20' �\ '-TANDARO EROSION ANOaOIMEN^CON.^^^.-L CONSTRUCTION PUN NOTES 1 \ SEPTEMBER.2CO3 (` 1I2.dTIXHOURS SPRIORTO TAWCONSTRUCT1M0UNSOTNBETHIS TSITE. O AT IEwSITWENIYFOVR F IND N ' I i 2.THERESHALLBENOEARTHOISTURBINGACTMIYCILTSIDETIEUMITS \ / OQu)N OESIONATEOONTHEACCEPTEDPLANS. a. a L - 3.ALLREOUIREDPERIMRSILTANDCONSTRIJCTIONFENCING,.XALLOE LL' J a) E T1➢, I I •'. LO INSTALLED PRIOR MAW LAND DI•TURBINCACTNRY(STOCKF1UNG. STRIPPING. � 7 JOMV IIIB J]. JT ZOEI ��' I I• SIT NG.ETC). ALL OTHER REQUIRED EROSION CONTROL MEASURES SHALL BE 4 UN(rj /I.TJ INSiALLEDATTHEAPPROPRIATETMEINTHECONSIR ON5 UENCEAS a S N(y _ 1 8 I INDICATED IN THE APPROVED PROJECTSCHEWLE,CONSTRUCTIONPIANSAND OI Ui & J 120 I •. I EROSION CONTROL REPORT. K RY IlL Z Q N 1a3 r /-^ l �. AATALLTMESDURINGCONSTRUCTION.THEDEVELpPEASHALLBERE NSB LL LL Q OIn \ 1' 1 - FOR PREVENTING ANDCONTROLLING ONS(TE EROSION INCLUDING KEEFNG THE IY (- J � j 0) /l PROPERTYSUFFICIENTLYWATEREDSOASTOMINIMREWINODLOWNSEDIMENT. 1' F O UJ TIE DEVELOPER$XALL ALSO BE RESPONSIBLE FOR INSTALLING AND MAINTAINING 4• I ALL EROSION CONTROL FACILITIES SHOWN HEREIN. Q _NUZ�x( PLAN A / I' I \ I'I f•' F- O Q Ptµ B \ \ Iw9 PLAN A 0 FF- 1&0 _ .11.51, I �' 1PRE-01 T RBANCEVEGETATONBHALLBEPROTECTEDANORETAINEDWNEREVER OIt 2: L IAIA / / /FF-IE.D / I\ I' POSSIBLE REMOVALOROISRIRBANCEOFEXIBTWGVEGETATONSHALLBEUMREO m OOa / FF- 188 / \` N 'I \ TOTHEAREAIA REQUIRED FOR IMMEDIATE CONSTRUCTION OPERATIONS. AND FOR l .. �5' 'I I / i i..; TIESHORTESTPTACRCALT•ERIODOFTME Q a 4' 1 ` \ •• / 25 •� I a L..� B. ALLSOILSEXPOSEOWRINCNNOOISM1IRBINGACTNRYISTRIPPNG.GRADING. i 203�I UTIUTYINSTALUTIONS.STOCKPIIJNGFIWNG,ICJ$HALLBEKEPTINA d RISpiS \ :1 / I 1 I,L2 I,LO / I ROUGHENEDCONORIONOYRIPHNGOROI.NGALONGUNDCONTIX UNTIL L ( •• I �I I MUCH.VEGETATIONOROTIERPERMANEM ER090NCONTROLBMPSARE •�2u \ ,. \/ 4;s INSTALLED, NO SOILSINAREAS OUTSIDE PROJECT STREET RIGHTSDFi AY SHALL 10i 12B0 'il• I� I REMAINS BEFOR BY LAND DISTIRSING ACTM1'RY FOE BEFORER MORE THAN THIRTY t SEEDAYSOEF.RND APING.EMNRARYORPERMANESSOT-E0NSEAPPR VED \ +l I /'I If . " `,I SEED/MVLCX.LANOSCAPING. ETCJISINSTALLEO, UNLESSOTHERN'ISE IPPROVED GARAGE � l •.I I I _ll BV THEcm NTv. /cou 120 I 120 OARA'�• I PLAN B I I 1 J, IN ORDER TO MINIMI EEROSION POTENTIAL ALLL TEMFORARY(STRUCTURA-1 /19d� \ \ - N ` FF- 140 I I I¢� I I EROSION CONTROL MEASURES SNALL L 20�I / b I,�„•I b ,,� I I' A. BE INSPECTED AT A WHIMM OF ONCE EVERY TWO QJ WEEKS AND AFTER EACH ,n 1 r SIGNIFICANT STORM EVENT AND REPAIRED OR RECONSTRUCTED AS NECESSARIIN v 4 ,GARAGE 'I I dPo3ER5 •' ; I •'I ORDER TO ENSURETIE CONTINUED PERFORMANCE OFTHOR INTENDED FUNCTION. P- ^ B.REMAININPACEUNTILSUCHTMEASALLTHESURROUNDINGDISTJMME EAS L 9Y O • y • Y / y` /, 20S I S I 'I ARE SUFFICIENTLYSTABILREO AS ORMINED BYTHE EROSION CONTROL �I �' h �.. { INSPECTOR J 9, 143J 19-90 115 I C BEREMOVEDAFTERTHESREHASBEFJJ3 CIENTLYST :1IEDAS y� O b . 1AeD �^ _ .' Izaa I •. 121 113 1 `..I OE7ERMINEDWTHEER0SI0NCONTROLINSPECT L �I Y 209 1180 ~ I / 01 , ( I ,i•' 1'_.f B.WXEN TEMPOgAIN EROSION CONTROL MEASURES ARE REMOVED. THE I 1aLb'' \ / b I OEVELOPERSHALL BE RESPoNSIBLE FORTHECLEAN UP AND REWWALOF ALL Q F 1A' I SEDIMENT AND DEBRIS FROM ALL DRAINAGE INFRASTRUCTURE AND OTHER PUDUC �S115� I I 110i1 1 E / Yf (y SRNY= , r FACIUTES. O 1 2 RISER9 IFIA C / 9 RISERS '( IE(L (1EK�AfChitl Id90 C R FF-16.8 / " PLANA 11d - PLAND '� AJNK�IAISBB MATERIALS NACVERTENLL DEPOSATELYCIEAN UPANYCONSTRULTON / MATERIAL9INAOVEfl1ENTlY DEPOSITED ON EXISTING STREETS. SIDEWALKS. OR FF�-�[-, FF- 1S0 FF- 12] 1' /'i :.i �' (.i I THEIR STREETS AND WAIKWAVSARE IR9 ' I � ', b' b � 16M �•� / I . •I b b _ _121 :I I CLEANED ATTIRE END OF EACH VaVRKING GAY. y, � 'Z V 101T / \ F I I' IOALLRETAINEOSEpIMENTSPAHTICUURLYTHOSEONPAVEOROADWAY O ® .n `- �• \ / 5 FACMSS BEREMOVEDANDOISPOSEDOFINAMANNERANDLOC ON50 /99 _ I AS MOTTO CAUSE THEIR RELEASE INTO ANY WATERS OFTIE UNITED STATES /9/ `', N < ` {L 91 �� / III _ 11. NO SQL STOCKPILE SHALL EXCEEDTEN 110)FEET INHEIGHT. ALISIDL - J4 IY'M / / II.SI Il. ]I •16.0 I -w 93�� \ � / / STOCKPILES SHALL BE PROTECTED FROM • SEDWENTTRANSPORT BY SURFACE L- �� �'-J ROUGHENING. WATERING. AND PERIMETER SILTFENCING. AWSOILSTOCKPLE t� l l Yn t�n g T (./1 •• �. _,- �.. r ___ REMAININGAR THIRTY I3010AYS SHALLBE SEEDED ANDMULCHED. _• ( �/ I I '•r 12.Cm ORDINANCEANOCOLORADO DISIMHARGE RMRI-CWTH{COP51 Z -+ ^a �� - r-- l�M = - _-�.�G --- J �'L�_-- - --�` I ',T/ -I_� gEOUIREMENTS MAKE II UNLAWFULTO DISCHARGE OgALLOW TIE DISCHARGE OF O __—T" =,. —I-- �_�-__\�=� - / I `L ___ ANVPOULTANTORCOWAMINATEDWATERFROMCONSRIVCIIONSITE.. Q AIL POLLUTANTS INCLUDE BUT ARE NOT UMRED TO DISCARDED BUILDING MATERIALS. CONCRETETRUCK WASHOUT. CHEMICALS OILAND GAS PROD UCTS, LITTER, AND \ / /I"•�1 SANRARYWASTE THEDEVELOPERSHALLATALLTMESTAKEWXAM/ER MEASURES ARE NECESSARY TO ASSURE THE PRO PERCONTNNMENTANODISPOSALOF O LOCALSTATE. I!I ON ADPEESRE INACCOROANCE WITH ANY AND ALLAPFLJI 19V L LOCAL STATE, ANpf EDERALgEGU1AT10NS 13.CONDMON51NTHEFIEI MAYWARRAWEROSONCONTTOLMEASURESIN J ADDITION TO WHAT IS SHOWN ON THESE P1,ANS THE ARj1/ 1511/ Ag11/ /)91Bi / I ' IMI ENTWHATEVER MEASURES ARE D DETERMINED ECESW .AS DIRECTED BY J I THECm/MSP:CMR, / j`� J -f ` - �\ ____ ___- _ _________ _"____ I / ANDAMXWUMRMEOFS CHIUS. ALL XAVEAMAYIMUM TRUD OF IOINCHES \ -� I• ��HA ANpALUY1MUM RISE OiJWCXES -t------- ---------------------- -- __-J \ /I 15. ALL DISTURBED AREAS SHALL BE REVEGETATEO PER THE UNDSCAPE PLAN -- _______�____- _ I p7 �- -- - �-- � __ / � 13 ( - NGNETESTJBgS. IS. UMRSOFSTREETCUTAREAPPROXIMATE, FINAL UMITSARETO REDETERMINED N ON ,� Q IN T IE FIELD BYCm ENWNEER INSPECroq.ALL REPNRS TO BE IN ACCORDO ANCE \ p < C WITH Cm STREET REPAIR STANDARDS. ^ � IJ. NO PROPOSED GRADING SHALL TAKE PLACEON ANYNEIGHpORING PROPER!'. O z IS a IS WX I OTY OF FORT COWNS. COLORADO o a a U UTILITY PLAN APPROVAL II Ij APPROW-D: CITY ENO'MFR CHECKED BY: GENERALNOTES IMIER • rOAg[EyATEp ITEITY I. ALLGRAOING 9 ALL 8E CONFlNED TOTXE PROPERTY BEING DEVELOPED, NO CHECKED BY' GMDINGSIU DEMNEOVTSIDEOFPROPER,YUNES. STORYWI.IFA Uln1TY CHECKED BY: - PAR15 � REaiEAnOI CHECKED BY: 1RAFiK O10KEW CHECKED BY: PROJ.140. 103fO U 021 3OF4 Cost Est EROSION CONTROL COST ESTIMATE Project: Rigden Farm Cottages Prepared by: E. Schneider Company: Interwest Consulting Group Date: 2/6/2008 ITEM QUANTITY UNIT COST/UNIT TOTAL COST Silt Fence 400 LF $3 $1,200 Inlet Protection 1 EA $150 $150 Construction Entrance 1 EA $550 $550 Subtotal Contingency (50%) Total $1,900 $950 . $2,850 CITY RESEEDING COST Reseed/Mulch 1 JACRE $775 $775 Subtotal Contingency (50%) Total $775 $388 $1,163 EROSION CONTROL ESCROW AMOUNT $2,850 Page 1 RUNOFF COEFFICIENTS & % IMPERVIOUS LOCATION: Rigden Farms Tract M3, M4 & D14 PROJECT NO: 1034-025-02 COMPUTATIONS BY: -ES SUBMITTED BY: Interwest Consulting Group DATE: 12/102007 Recommended Runoff Coefficient from Table 3-3 from City of Fort Collins Design Criteria Recommended % Impervious from Urban Storm Drainage Criteria Manual Streets (paved) Drive & walks Roofs Lawns Flat <2% (sandy soil) Runoff Coefficient C % Impervious 0.95 100 0.95 96 _ 0.90 90 0.10 0 SUBBASIN DESIGNATION TOTAL AREA (ac.) TOTAL AREA - (sq.fl) ROOF - AREA (S00 PAVED AREA (s40) SIDEWALK AREA (sq.a) LANDSCAPE AREA (sq.0) RUNOFF COEFF. % Impervious Lot M3 0.34 15 015 3 509 0 2,247 B 259 0.41 35 Lot M4 0.42 18 333 3.509 0 2,947 11,877 0.39 33 Lot D14 . 0.31 13 292 2 161 0 2,382 8,749 0.38 32 Tract AN 1 0.07 1 3.166 1 0 10- 0 3.166 1 0.10 0 Total 1.14 49,806 Weighted 0.38 31 - Calculated C coefficients & % Impervious are area weighted C=E(Ci Ai) /At Ci = runoff coefficient for specific area, Ai Ai = areas of surface with runoff coefficient of Ci In = number of different surfaces to consider At = total area over which Cis applicable; the sum of all Al's .A FEB 2 5 2W FINAL DRAINAGE AND EROSION CONTROL REPORT Rigden Farm -Filing Six Prepared for: Rigden Farm LLC c/o Wheeler Commercial .1027 W. Horsetooth Road, Suite 200 Fort Collins, Colorado 80526 (970)225-9305. Prepared by: JR Engineering' 2620 E. Prospect Road, Suite 190 Fort Collins, Colorado 80525 .(970) 491-9888 Revised February 8, 2002 Revised December 5, 2001 Revised July 25, 2001 Revised March 28, 2001 December 13, 2000 Job Number 9164.12 I 131 will flow along alleys parallel to Rigden Parkway and Annelise Way to Design i 1 Points 26 and 31 respectively. Sump inlets at Design Points 26 and 31 will collect flows to be conveyed to Water Quality Detention Pond 3.Runoff from Sub -basin 130 will flow along the north side of Rigden Parkway from Tarpan Lane to an on -grade inlet at Design Point 30, located just west of Chase Drive. Flows from Sub -basin 132 flow along the south side of Annelise Way to Design Point 32, where an on -grade inlet i collects flows to be conveyed to Water Quality Detention Pond 3..Runoff fromiS'uM " 'and OS-12 is conveyed along the south side of Rigden Parkway to an on - grade inlet at Design Point 34 from which flows are conveyed to Water Quality Detention Pond 3. Runoff from Sub -basin 135 will flow directly to Water Quality ' Detention Pond 3. ' Runoff from Sub -basin 136 will flow on the: north side of Rigden Parkway and conveyed to an.on-grade inlet at Design Point 36. Runoff from Sub -basins 138 and 139 will flow east along David Drive and south along Cobb Drive to Design Points 38 and 39 respectively., Flows from Design Points 38,and 39 and runoff from Sub -basin . 141 are conveyed along the north side of Rigden Parkway to a sump inlet at Design Point.41. Runoff from Sub -basin 137 will flow along an alley parallel to Rigden Parkway to a sump inlet at Design Point 37. Flows from Design Points 36, 37 ,and 41 ' are conveyed to Pond 269 in a storm sewer system. Runoff from Sub -basin 143 will be collected north of Rigden Parkway and conveyed in a storm sewer to Design Point 41. Runoff fro ffiNg Ni M145,146, and OS-13 will be conveyed to Design Point 46 at the intersection of Bryce Drive and Rigden Parkway. Flows from Design Point 42 and runoff from Sub -basin 142 will be conveyed to Design Point 42, a sump inlet to ' be located on the south side of Rigden -Parkwayjust west of Ziegler Road. Flow at Design Point 42 will be conveyed via storm pipe to Pond 269. ' Runoff from(5Ub 4iN9VffMnd OS-14 will flow south along Chase Drive to. on - grade inlets north ofLippizan Court. The inlets will discharge to a Swale, which will be collected by a storm sewer which conveys flows eastward into Pond 269. Runoff ' from Sub -basins 150 and 153 will be conveyed in swales to Design Point 53, an inlet to be located west of Bryce Drive. Runoff from Sub -basins 147 and 151 will flow Drainage and Erosion Control Report Page 9 ' Rigden Farm — Filing SixFebruary 8, 2002 . 0 1 1 1 1 1 1 1, 1 DRAINAGE SUMMARY TABLE Design Point Tributary Sub•basln Area (ac) C (2) C 110) C 1100) tc (2) (min) Ic (10) (min) tc (100) (min) Q(2)lol (cfs) Q(10)Iot (cfs) Q(100)10t (cfs) DRAINAGE STRUCTURE /REMARKS 1 101 1.33 N/A 0.83 1.00 N/A 6.4 5.0. N/A 5.20 13.3 102 0.84 N/A 0.84 1.00 N/A 5.0 5.0 N/A 3.46 8.4 2 102+204 1.27 NIA 0.84 1.00 N/A 5.6 5.0 N/A 4.92 12.6 103 0.47 N/A 0.82 1.00 N/A 5.0 6.0 N/A 1.86 4.6 3 103+205 0.61 N/A 0.82 1.00 N/A 5.0 6.0 N/A 2.44 6.1 4 104 0.77 N/A 0.82 1.00 N/A 5.2 6.0 N/A 2.99 7.7 105 2.18 N/A 0.05 1.00 N/A 10.5 7.3 N/A 6.91 19.0 6 106 0.26 N/A 0.79 0.99 N/A 5.0 5.0 N/A 0.99 2.5 Double Combo Inlet 7 107 0.26 N/A 0.78 0.98 N/A 8.9 . 7.7 N/A 0.81 2.2 Single Combo Inlet 8 108 1.78 0.63 N/A 0.79 9.0 N/A 8.1 2.6 N/A 12.1 Ex Triple Combo Inlet 9 109 2.79 NIA 0.76 0.96 N/A 8.5 7.0 N/A . 0.61 23.6 Ex Tdple Combo Inlet 110 1.61 N/A 0.84 1.00 N/A 10.7 7.2 N/A 5.01 14.1 10 110+206 2.01 1 N/A 0.84 1.00 N/A 10.9 7.2 N/A 6.19 17.7 111 0.78 0.67 N/A 0.63 11.6 NIA 7.6 1.1 N/A 5.6 11 11 1+208 0,99 1 0.70 N/A 0.87 11.5 N/A 6.9 1.4 - N/A 7.6 112- 1.47 0.66 N/A 0.83 12.3 N/A 10.3 2.0 N/A 9.4 12 .112+209 1.86 0.70 N/A 0.87 12.3 N/A 8.8 2.6 N/A 13.1 13 113 2.55 0.67 N/A 0.83 12.5 N/A 8.3 3.7 NIA 24.6 Ex 15'Type R Inlet 114 2.23 N/A 0.31 0.39 N/A 7.7 7.2 N/A 2.91 7.6 14 114, 202, 203, OSd' 5.90 N/A 0.33 0.41 N/A 11.4 16.6 N/A 6.92 . 14.9 .14d 114,202,203,OS4,OS-3 12.44 N/A 0.75 0.93 NIA 12.9 11.4 N/A 31.75 85.4- 115 0.79 0.60 N/A 0.75 13.8 N/A 12.0 0.9 N/A 4.3 15 115+OS-6 . 1.05 0.61 N/A 0.77 14.5 N/A 12.5 1.2 N/A 5.7 Triple Combo Inlet . 116 2.41 0.67 N/A 0.84 12.6 N/A 9.8 3.3 N/A 15.9 16 116+OS-9 3.43 0.67 N/A 0.83 14.5 N/A 11.4 4.3 NIA 21.0 Quadruple Combo Inlet 117, 2.36 0.68 N/A 0.85 10.5 N/A 7.6 3.5 WA 17.2 17 117+OS-10 3.03 0.67 N/A 0.84 10.9 N/A 7.9, 4.4 N/A 21.6 Quadruple Combo Inlet 18 118 0.38 0.71 N/A 0.89 5.0 N/A 5.0 1.4 N/A 12.4 10' Type R Inlet 1Be Ilea 0.19 0.73 N/A 0.91 5.0 N/A 5.0 1.1 N/A 4.3 5' Type R inlet 119 0.43 0.10 N/A 0.13 7.4 N/A 7.2 0.1 N/A 0.5 20 120 1.14 0.68 NIA 0.85 7.7 N/A 5.3 1.9 N/A 9.3 3-Type 13 grated Inlets 21 121 0.39 0.69 N/A 6.86 6.4 N/A 6.0 0.7 N/A 3.4 5' Type R Intel 122 0.95 0.67 N/A 0.84 9.6 N/A - 6.4 1.9 N/A 10.9 122a 0.64 0.71 N/A 0.88 7.3 NIA 6.0 1.1 N/A 5.3 22 122+122a 1.60 0.68 N/A 0.86 9.5 N/A 8.3 3.0 N/A 16.7 10' Type R Inlet 123 . 0.39 0.10 N/A 0.13 10.6 N/A 10.6 0.1 N/A 0.4 124 - 4.66 0.58 N/A 0.73 16.1 N/A 16.1 4.9 N/A 21.4 24 124+OS-11 6.60 0.60 N/A 0.75 16.5 N/A 16.5 6.4 N/A 27.9 Double Combo Inlet 125 2.01 0.61 WA 0.76 14.0 N/A 12.5 2.8 N/A 15.0 26 126 2.01 0.68 N/A 0.85 10.2 N/A 7.7 3.0 N/A 14.6 5-Type 13 grated inlets 127 1.83 0.68 N/A 0.85 9.9 N/A 8.8 2.8 N/A 12.8 . 25 125+127 3.85 0.64 N/A 0.80 12.1 N/A 12.1 5.5. N/A 26.4 To basin 132 28 128 1.71 0.60 N/A 0.85 12.4 N/A - 10.5 2.4 N/A 11.1 To basin 133 29 129 1.55 0.48 NIA 0.60 16.0 N/A 15.0 1.4 N/A 6.1 Swale to Grated inlet 30 130 0.78 0.59. N/A 0.73' ` 9.7 N/A 8.3 1.0 N/A 4.8 Single Combo Inlet 31 131 1.53 0.68 N/A 0.85 8.1 NIA 6.2 2.6 N/A 11.9 4-Type 13 grated Inlets 132 - 1.02 0.66 N/A 0.83 6.1 N/A 6.0 1.8 N/A 23.9 32 125+127+132 4.87 0.65 . N/A 6.81 17.2 N/A 15.7 6.9 N/A 29.3 Triple Combo Intel 33 133 0.69 0.68 N/A 0.82 8.7 N/A 6.3 - 4.6 NIA 34.0 Triple Combo Inlet immalmom 1.88 0.64 N/A 0.80 13.1 N/A 10.3 '3.9 WA 25.7 34 2.43 0.64 N/A 0.80 13.7 N/A 10.7 4.5 N/A 28.9 Triple Combo Inlet 35 135 5.30 . 0.38 WA 0.47 14.9 N/A - 14.9 3.7 N/A 16.3 WQ Pond 3 36 136 2.94 0.72 WA 0.90 13.6 N 4.1 WA 18.8 Double Combo Inlet 37 137 1.05 0.69 NIA 0.87 9.3 NIA 7.1 1.7 . .NIA 8.0- 3-Type 13 grated Inlets 38 138 0.50 0.65 N/A 0.81 6.6 N/A 5.3 1.2 N/A 7.0 9164flow.xls Page 1 DRAINAGE SUMMARY TABLE Design Tributary Area C (2) C (10) C (100) ,to (2) tc (10) lc (1 10) q(2)tot 0(10)tot Q(100)tot DRAINAGE Sub -basin Point - - (a°) � (min) (min ) (min) (cfs) (cfs) (cfs) STRUCTURE /REMARKS 39 139 0.58 0.72 NIA 0.90 1 6.9 N/A 5.2 1.1 N/A 5.0 41 A2 141 bltl' `XiaTs'41a 0.32 c .. 0.73 N. A 0.91. 5.0 �� - ... _ __ .- - N/A 5.0 3.4 N/A 22.7 15' Type R inlet ...�88 rvrA 1u.0 7.2 NIA 46.5 Quadruple Combo Inlet 142 1.01 0.71 N1A 0. 9.7 NIA 8.2 7.5 143 1.04 0.44 NIA 0.55 8.1 NIA 7.3 1.1 N/A 5.0 Swale to FES `$ 1.73 0.65 N/A 0.82 9.4 NlA 6.5 2.6 N/A 12.8 145 0.20 0.74 N/A . 0.92 5.0 N/A 46 y1 G '-�' 4.10 0.65 N/A 0.81 10.9 N/A 0.1 6.1 N/A 40.7 146 2.37 0.64 N/A 0.80 12.1 N/A 9.0 3.1 N/A 15.4 147 .0.39 0.68 N/A 0.85 5.0 N/A 5.0 0.8 N/A 3.3 46 =e14BrrreFk['a. 3.10 0.67 N/A 0.84 14.8 N/A 12.4 3.9 N/A 18,q 49 149 0.76 0.73 N/A 0.91 11.0 N/A 9.3 1.2 N/A 5.5 - 150 2.59 0.64 N/A 0.67 13.4 NIA 11.9 2.7 N/A 12.5 Swale 151 1.16 0.63 N/A 0.79 8.8 N/A 7.1 1.7 N/A 8.0 152 0.49 0.74 N/A 0.92 6.8 N/A 5.3 0,9 NIA 4.3 - 153 2.20 - 0.41 . "N/A- .0.51 9.6 N/A 8.7 2.0 N/A 8.2 Swale 53 150+153 4.78 0.48 N/A 0.60 13.8 N/A 13.8 4.4 N/A., 19.3 3-Type 13 grated inlets 154 1.05 0.63 N/A 0.79 11.1 54 147+149+161+154+165 3.83 0.67 N/A 0.83 16.6 NIA 11.6 4.5 .N/A 1 23.2 20'Type R Inlet 156 0.45 0.66 . NIA 0.82 7.5 N/A 6.2 0.7 N/A 3.4 56 - 152+156 0.94 0.70 .N/A 0.87 7.2 N/A 5.8 1.6 N/A 7.7 5' Type R inlet 157 1.50 0.61 N/A 0.76 7.5 N/A 6.1 2.3 N/A 10.6 159 1.48 0.62 NIA 0.78 7.9 N/A 6.6 2.2: N/A 10.- 59 157+159 2.98 0.62 NIA 0.77 7.9 N/A 6.7 4.5 N/A 20.7 5-Type 13 grated inlets 160 1.14 0.61 NIA 0.76 6.3 N/A 7.4 .1.7 N/A 7.5 162 1.18 0,64 N/A 0.80 11.8 7.5 62 160+162 2.32' 0.62 NIA 0.78 8.2 N/A 7.3 3.5 N/A 15.8 10' Type R inlet 163 0.64 0.71 N/A 0.89 8.2 N/A 6.7 1.1 N/A 5.1 164 0.67 0.65 N/A 0.82 11.0 N/A 10.3 0.9 N/A 4.2 64 163+164 1.31 0.68 N/A 11.85 11.6 N/A 10.0 1.9 N/A 0.7 10' Type R inlet 165 0.46 0.71 N/A 0.89 5.0 N/A 5.0 66 166 0.30 0.66 N/A 0.83 54 N/A 5.0 0.6 N/A 2.5 5' Type R inlet 167 2.72 0.67 N/A 0.71 9.5 N/A 7.5 3.5 N/A 16,8 67 168 4i¢yffb`+pf87�$b 2.10 7.91 0.65 N/A - 0.81 10.4 N/A 7.3 % 33.1, 0.63 N/A 0.79 16.8 N/A 13.9 8.8 N/A 41.9 quadruple Combo Inlet 169 0.25 0.69 NIA 0.85 6.0 N/A 5.0 0.5 . N/A 2.2 170. 0.81 0.55 N/A 0.68 10.2 NIA 7.9 1.0 N/A- 4.7 171 11.50 0.28 N/A 0.35 12.3 'N/A'. 12.3 6,6 NIA 28.9 72 172 0.33 0.77 N/A 0.96 5.b N/A 5.0 0.7 N/A 3.1 Single Combo 101e1 73 173 0.85 0.74 N/A . 0.93 '5.0 N/A 5.0 4.0 NIA 79.0 174 2.49 0.54 N/A 0.67 11.2 N/A 10.4 2.8 N/A 12.8 74 - 173+174+OS-14 5.49 0.55 N/A 0.68 23.9 N/A T3.9 4.8. N/A 35.0 75 176 1.85 0.31 N/A 0.38 14.5 N/A 14.5 1.1 N/A 4.7 76 77 176 3.76 0.69 N/A 0.87 8.3 N/A e.4 6.2 NIA 27.0 15' Type R inlet 177 0.49 0.73 N/A 0.92 6.4 N/A 5.2 0.9N/A 4.3 . 20' Type R Inlet 178 1.08 0.26 N/A - 0.32 11.7 N/A 11.7 0.6 N/A 2.5 79 179 1.04 0.49 N/A 0.61 12.7 N/A 12.7 1.0 N1A 4.5 Swale 78 175+178+179 3.97.. 0.34 N/A 0A3 15.9 NIA 15.9. 13.5 N/A . 72J Swale 180' 1.59 0.61 80• 180+OS-13+R125 6.80 0... N/A 0.76 16.5 N/A A5.1 7.3 N/A - 181 1.30 0.70 NIA 0,87 13. 3 33.4 Double Combo Inlet N/A 9.6 1.8 N/A 9.0 182 1.65 0.46 N/A 0.57 13.0 NIA 13.0 t.5 N/A 6.8 .83 183 2.75 0.19 N/A 0.23 12.9 N/A 12.9. 13.3 N/A 66.0 184 1.14 0.53 . N/A 0.66 7.7 NIA 6.6 1.5 NIA 8.8 84 184+OS715 - 2.16 0.62 N/A 0.77 6,9 N/A 5.9 3.8 NIA 21.4 Combo Intel 82 181+182 2.95 0.56 NIA 0.70 14.7 N/A 14.7 5.0 N/A ,quadruple 31.9 quadruple Combo Inlet . 9164flow.xls Page 2 JR Engineering 2620 E. Prospect Rd., Ste. 190 Fort Collins, CO 8525 RUNOFF COEFFICIENTS & % IMPERVIOUS LOCATION: Rigden JJ PROJECT NO: 9164-12 and 9164.15 COMPUTATIONS BY: B. Strand . DATE: �2 s`o � Recommended Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria Recommended % Impervious from Urban Storm Drainage Criteria Manual C Streets, parking lots (asphalt): 0.95 100 Sidewalks (concrete): 0,95 96 Lawns (flat <2%, sandy soil): 0.10 0 General multi -family area: 0.65 70 General single-family area: 0.65 55 General commercical area: 0.85 90 SUBBASIN TOTAL TOTAL SIDEWALK PAVED LANDSCAP MULTI- SINGLE- DESIGNATION AREA AREA AREA AREA AREA COMMER, RUNOF F % (ac.) (sq•B) (sq.n) (sq.ft) FAMILY FAMILY AREA COEFF. ImpeMous . (sq.f1) (sq.e) (sq.fl) (sq.n) (C) 101 1.33 58,112 2,58E. 14,357 3,617 102 .0.84 36,774 1.062 5,797 1,387 0 0 37,552.. 0.83 87 103 0.47 20,323 1,170 6,213 1, 0 0 28,528 BB 104 0.77 33,815 2,716 17,415 4,055055 0 11,126' - 0.82 85 105 2.18 94,889 0 0 0 0 9,430' 0,82 85 106 0.26 77,785 f,3B0 7, 758 0 2,050 0 0 94,BB9 0.85 90 107 - 0.28 11,351 1,399 7691 2,265 p tip 0 0 ,. 0.79 B1 .108 1.78 777f0 5, B20 25, 261 19,0f8 27,813 - - 0 0.76 80 109 2.79 121, 708 5,405 21,874 17729 0 p . 0 0.83 65 110 1.61 . 69,951 920 3,321 11122 p 0 76,700" 0.76 79 111 0.78 34,05E B87 3,214 1,131 0 B4,SB95 0.67 B9 112 1.47 63,859 1,222 4,169 1,348 � 28,825 57, 121- ' p 0 0.66 77 - 113 _ 2.55 110,869 Z807 laddy 4,104 93,069 0 0 0.68 71 114 2.23 97,333 3.060 20.956 73,317 0 115 0.79 . 34,492 2,7,728 B,4B2 - 0 0 0 0.31 25 118 2.41 105,098 3,449 449 f1, iHB 5,051 15,914 p . 0.60 54 2.36 102,BB7 $2B8' 15,756 5.083 0 0 B2,412 0 0.67 60 116 Ila 0.38 18,381 1,229 � B,B00 3,593 59 0 O.6B' 60 118a _ 0.19 8,409 1,041 � 5,196 2,172 0 2,959 2, 0 0.71 70 it9 0.43 18.707 0 0 p 0 0 0.73, 74 120 /.14 49,687 0 4,571 18,707 0 p p 0 0.10 p 121 0.39 17079 I,H41 B,B84 3,425 0 45,118 0 �'O.BB 59 122 0.95 01,588 2,819 10,383 5, 771 0 0 ,.5, 148 p 0.fi9 86 122a 064 28,049 2,30J 10,284 3,8B1 0 0.67 62 123 0.39 /709' 0 - 0 p 11.502 11,502 0 - 0.71 67 124 1.68 203,091-5, 785 13,738 17,093 34,583 0 0 0 0.10 0 125 2.01 H7885 5,625 24,464 23,378 0 150,224 0 O.SB 50 126 _ .2.01 87,631 0 8,380 0 0 34,21E 0 0.61 Sfi 127 1.83 79,819 3, 781 13,161 4,888 0 0 79,250 0 0•� 59 128 1.71 74,660 5,060 . 14,251 6,619 0 58,187 0 O.BB 81 129 1.55 67,649 0 0 20,8/7 48,730 0 O.BB 61 130 0.78 34,153 2,475 9,394 � � f0,JB0 0 47,032 p - 0.4E 39 131 1.53 66,622. 0 5,,i41 1,870� 10,253 132 1.02 44,601 1,770 5,841 � 0 3,305 11.272 49,186 0 0.88 82 133 0.69 30,115 1,880 9183 5,54ENo 0 8,159 33,885 0 0.68 SB 1.8a 81,946 2,413 11, 044 8,083 0 0.88 6g 35 5.30 231,008 14,400 0 122, 508 8, 198 3201 0 0•� 57 36 _ 2.94 128,1to 8,080 34,045 LI 6,658 38,887 3,280 55,1 i8. p - 0.3E - 3t 78, 107 0 0.72 67 rrn Page 1 LOCATION: Rigden 11 PROJECT NO: 9164.12 and 9164.15 COMPUTATIONS BY: B. Strand DATE: t - O, Recommended Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria Recommended % Impervious from Urban Storm Drainage Criteria Manual Runoff 0/ coefficient Impervious C Streets, parking lots (asphalt): 0.95 .100 Sidewalks (concrete): 0.95 96 Lawns (flat <2%, sandy soil): 0,10 0 General multi -family area: 0.65 70 General single-family area: 0.65 55 General commercical area: 0.85 90 JR Engineering 2620 E. Prospect Rd.. Ste. 190 Fon Collins. CO 8525 Page 2 No Text