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HomeMy WebLinkAboutDrainage Reports - 05/03/2000Final �f a*. / &0 Drainage Report and Erosion & Sediment Control Report Grease Monkey International Denver, CO 80202 -, But, I dpp, FARNS//WORTH&..}� POLK 14 fw /b Ley � '�l.Ni1'11".i10'LUL U)76.G �-p Drainage Report and Erosion & Sediment Control Report Project: Lot 1 ' Replat Lot No. 1 of Country Club Corners, Third Filing City of Fort Collins, Colorado ' Prepared for: Grease InternaflonaR 216 16`h Street, Suite 1100 ' Denver, CO 80202 (303) 534-1660 phone ' (303) 534-2906 fax Prepared by: ' Brian J. Jascott, P.E. Registered Professional Engineer State of Colorado No. 12558 1 ' Date: June 19, 1998 Sept. 29, 1999 'Rev. FP #: 398035.1 For and on behalf of.- , Farnsworth & Polk a mrrwGiit, o� ttw �a2rvlurort� 'u%� �",�. 2696 S. Colorado Blvd., Ste. 250 Denver, CO 80222 (303) 692-8838 • Phone (303) 692-0470 • Fax 1 1 1 1 Drainage Report And Erosion and Sediment Control Report Lot 1 Replat Lot No. I of Country Club Corners, Third Filing City of Fort Collins, Colorado TABLE OF CONTENTS I. Introduction............................................................................................... 1 H. Design Criteria.......................................................................................... 1 III. Drainage Basins........................................................................................ 1 N. Erosion Control Measures.........................................................................2 V. Conclusions...............................................................................................2 VI. References.................................................................................................2 Appendix A APPENDIX Drainage Report And Erosion and Sediment Control Report Lot I Replat Lot No. 1 of Country Club Corners, Third Filing City. of Fort Collins, Colorado CERTIFICATION I HEREBY CERTIFY THAT THIS Drainage Study for Lot 1, Replat Lot No.I of Country Club Corners, Third Filing, a Planned Unit Development was prepared by me or under my direct supervision in accordance with the provisions of the City of Fort Collins Storm Drainage Criteria for the Owners thereof. Brian J. Jascott, P.E. Registered Professional Engineer State of Colorado No. 12558 ' Drainage Report And Erosion and Sediment Control Report ' Lot I Replat Lot No. I of Country Club Corners, Third Filing City of Fort Collins, Colorado I. INTRODUCTION ' This report is being prepared for Grease Monkey International, owner and developer of Lot 1, ' Replat Lot No. 1 of Country Club Corner, Third Filing, to fulfill the drainage requirements of the City of Fort Collins, Colorado. The intent of this report is to show that the development of Lot 1 conforms with the approved "'Final Drainage Study for Country Club Corners, a Planned Unit Development" prepared by Landmark Engineering Ltd. For the overall Country Club Corner ' development. The 0.51 acre site is part of the northwest'/a of Section 1, Township 7 North, Range 69 West of ' the Sixth Principal Meridian, City of Fort Collins, Larimer County, Colorado. The site lies at the northeast intersection of North College Avenue and Bristlecone Drive. ' II. DESIGN CRITERIA ' This report was prepared using criteria as outlined in the City of Fort Collins' "Storm Drainage Design Criteria and Construction Standards" manual. Runoffs for the 10-year (minor storm) and the100-year (major storm) frequencies were calculated using the Rational Method for the fully ' developed conditions. Due to the small size of the basin, ten minutes was used as the time of concentration. Rainfall intensity values were derived from the City of Fort Collins' intensity - duration -frequency curves. Composite runoff coefficients were calculated for the individual basins. Calculations and applicable support data are included in the appendix of this report. Since detention facilities are included elsewhere in the overall County Club Comer development, on -site detention facilities for Lot 1 are not required. ' III. DRAINAGE BASINS ' The Grease Monkey site (Lot 1), is approximately 1/3 of the overall Cl drainage basin identified in the "Final Drainage Study for Country Club Corner" by Landmark Engineering. The overall C1 basin (1.51 acres) consists of Lotl (Grease Monkey), Lot 2 (Big "O" Tire) and a portion of the ' north access road from Bristlecone Drive into the Country Club Corners development that lies immediately south of Lots 1 and 2. The overland drainage flow from the overall Cl basin is to the southeast towards the intersection of the aforementioned access road and Bristlecone Drive ' where the drainage flows east along Bristlecone where it is picked up by the storm drainage facilities for the Country club Corner development. The proposed drainage flow from the Grease Monkey site follows the same drainage pattern. The 10-year and 100-year composite "C" factors for the Grease Monkey parcel are 0.80 and 1.00 respectively. These are lower than the composite C-factors of 0.90 and 1.00 for overall Cl basin. ' Therefore, the storm drainage contribution from the Grease Monkey site is less than the planned runoff and the Grease Monkey development should not overload the downstream drainage facilities or street capacities. t ' Page 1 ' Drainage Report And ' Erosion and Sediment Conn-ol Report Lot Replat Lot No. I of Country Club Corners, Third Filing ' City of Fort Collins, Colorado The site lies in the 100-year flood plain fringe of the Dry Creek drainage basin. More ' specifically, the Grease Monkey site lies between cross section 27 (100-year elevation = 4975.9) and cross section 28 (100-year elevation = 4977.3). The 100-year elevation of the Grease Monkey building has been interpolated to be 4976.7. The proposed finish floor elevation for the Grease Monkey building is 4979.70 resulting in a freeboard of 3.00 feet, well above the 1.5 feet ' required. ' IV. Erosion Control Measures Erosion and sediment control measures were developed utilizing the City's "Erosion Control ' Reference Manual for Construction Sites". Due to the small size of the site (0.51 acres), provisions for wind erosion are not required. Rainfall erosion control will be handled by three processes: 1) roughening of soil, 2) hay mulching in all proposed landscape areas and 3) ' installation of a silt fence to intercept all overland flows exiting the site. The site will be rough graded to direct all runoff towards the silt fence. All of the above measures will remain in place throughout the estimated three-month construction phase until all pavement and landscaping areas have been completed. The rainfall performance standard evaluation form, effectiveness calculation form and construction sequencing form are included in the appendix ' V. Conclusions Runoff from the proposed Grease Monkey site complies with the drainage patterns and flows ' established on the approved drainage report for County Club Corners. VI. References ' Final Drainage Stttdv for Cottntry Club Corners, a Planned Unit Development, by Landmark Engineering Ltd., updated July 10, 1995. Storm Drainage Design Criteria and Construction Standards, City of Fort Collins, May 1984 as revised. ' Erosion Control Reference Manual for Construction Sites, City of Fort Collins, January 1991. t r ' Page 2 1 1 1� 1 1 Drainage Report And Erosion and Sediment Control Report Lot I Replat Lot No. I of Country Club Corners, Third Filing City of Fort Collins, Colorado APPENDIX A Paoe 3 VICINITY MAP HIS --••`x-r. =�-;-•' 10730 E. Bethany give: Suite 202 'n Aurora, Colorado 80014 FARNSWORTH & POLK Phone:303-671-9105 i Project �/LG—n sE _ o /j�c�/Co61-6GC F �2,g77ECO,A-5 Project No. Subject 7_7__-�reni e C Cr+ -e- r- Co�rlPo s rct C -721 Or- — �,q s , / C- A A 2OaFa o. 95 /GG � /S8o �n2io,�✓Cr o.45 ISG3 Z /� SSo ZZ i'J" 9F 17634— AC icy -fit �oirlPoS.TE C '� sheet � of Made by �J-� date ix-''. 3-►-�_` 9-z4_g9 ChM. by date 3 1 8 3S. - zz.ii o.gv x iz.5 Lcr TiR b- o � Go�✓Gd�r/!/r +'7o n� . U F L C. / � '��' ^� rlo = 4. 'Ie 5 T, U O :;P r%. ZiO o. aO (4.4� �(o.S�� _ <.B z c4L i, o ' Table 3-3 RATIONAL METE013 RUNOFF COEFFICIENTS FOR C0-120SITE ANALYSIS ' Character. of Suxfaca Runoff Coefficient ' Streets, Parking Lots, Drives: Asphalt ...................................... 0.95 Concrete........ r............................ 0.95 Gravel....................................... 0.50 ' Roofs .......................................... 0.95 Lawns,' Sandy' Soil:" "" Flat<23..................................... 0.10 Average 2 to 7%.............................. 0.15 Steep>75 .............. ................. ... 0.20 t Lawns, Heavy Soil: Flat<23..................................... 0.20 Average 2 to 7%.............................. 0.25 Steep>7%..................................... 0.35 ' 3.1.7 Time of Concentration In order to use the Rainfall Intensity Duration Curve, the time of ' concentration must be known. The time of concentration, T„ represents the time for water to flow from the most remote part of the drainage basin under consideration to the design point under consideration. The time of concentration can be represented by the following equation. ' T. = tav + tt Where: ' T� = Time of Concentration, minutes ta, = overland flow time, minutes t, = travel time in the gutter, swale, or storm sewer, minutes ' The overland flow time, t,,, ,can be determined either by the following equation or the "Overland Time of Flow Curve$" from the Urban Storm Drainage Criteria Manual, included in this report (See'Figure 3-2)• ' L87(1.1-CC,)Lll2 TO1 sl/3 ' Where: T„ = Overland -Flow Time of Concentration, minutes S = Slope, % C = Rational Method Runoff Coefficient ' D = Length of Overland Flow, feet (500' maximum) Ct Frequency Adjustment Factor The travel time, t,, in the gutter, Swale, or storm sewer can be estimated with ' the help of Figure 3-3. . 3.1.8 Adjustment for Infrequent Storms The preceding variables are based on the initial storm, that is, the two to ten year storms. For storms with higher intensities an adjustment of the runoff coefficient is required because of the lessening amount of infiltration, depression retention, and other losses that have a proportionally smaller ' effect on storm runoff. These frequency adjustment factors are found in Table 3-4. ' May 1984 Design Criteria Revised January 1997 3-5 No Text 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 RAINFALL PERFORMANCE STANDARD EVALUATION . -------------------- -------------------------------------- PROJECT: Gn_�s-er oof1ee-/r Ne- Coif EGF a�'3 ,STANDARD FORM A COMPLETED BY: �Z���-�AS�TFt�/=wrC waK DATE: - ------------------------------------------------------------------- DEVELOPEDIERODIBILITY1 Asb I Lsb Ssb I Lb I Sb I PS SUBBASIN I ZONE I(ac)--I (ft) I (%) .I(feet) I (�) I (0) - --------- I ----------- I ------- ------- ------- I ------- I------- c 1 n9o7?LexAl-� i I I I )? Z I /, 7 1 -78. 3 1 ------------------------------------------------------ ,DI/SF-A:1989 EFFECTIVENESS CALCULATIONS ------------------------------------------------ ----------------------� PROJECT: G"Ase- 4n1k-d-,Y rdef'Coc. �---"f-,..J<STANDARO FORM B ' COMPLETED BY: ?,�•� �Icasco-� ��t ✓s •� rT-✓ ��,c. DATE: Erosion Control Method ---------------- S-ter fE-.vcc� MAJOR BASIN C PS 76. 3 SUB BASIN C AREA (Ac) C-factor P-Factor Value Value Comment o, 9 T 6� S• Z O.o� 1. o " •� --------------------------------------------- CALCULATIONS -------------------------------------------- z /. 4 / X o. 5! 11 -1 c %ZorJG HEsn/Ertl So. L ,�. /�c ,n o ....._ ....... --._............. O. / -------------------------------------------- I/SF-6:1989 ' CONSTRUCTION SEQUENCE PROJECT: a`«^ sc i�/o.JlcG� Zoo 0 'QUENCE. FOR ONLY COMPLETED BY:Zi�ri✓ sc vT STANDARD FORM C DATE: g — 7-9 - qq dicate by use of.a bar line or symbols when erosion control measures will be installed jor modifications to an approved schedule may require submitting a new schedule for approval by the City Engineer. ' YEAR MONTH ----------------------------I �ERLOT GRADING WIND EROSION CONTROL 'Soil Roughing Perimeter Barrier Additional Barriers 'Vegetative Methods Soil Sealant Other 1INFALL 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 ' Mul:ching/Sealant Tempordry'Seed Planting Sod Installation t Nettings/Mats/Blankets Other J MI /q I1-4 I J I j I/I I s I oI gib --------;------------------------------------------------- ---------------------------------- i---------- --------------- ITRUCTURES: INSTALLED BY MAINTAINED BY _ IEGETATION/MULCHING: CONTRACTOR DATE SUBMITTED IDI/SF-C:1989 .1 APPROVED BY CITY OF FORT COLLINS ON ---------------- MONARCH DSr. - ------- MET E SXG 60C O ROUE II � p$IE DRUG MATCH EAST p p MIWeW \ I II I ' CURB CUT TRIO p YRCN EXIST . Q ( - I p IR I� L TRY-III-�.ra tIIIIIIIA�'A�orjA, y, p .__ ] wiNa.unN � H I I / �a aGPINc CENTER AccEss SAD N / CALL unlit COLOR) OLOR G11TER OF calN FOR HLM.92� - - 1-800- 1987 s- CAL �I UEMMR U,UEs. NORTH COLECEAW 4w4mv'Raw wmw — -. p a -- _ _ L \ —&KE RACK ] 70 ]9.], yy\ \ ( ENRON PAW p�]p I WLL A BAY PI \ (PITSTS WILL BE WATER PROCEED j ARE CONTAIN ENO WIPNENTJ $ IBID - -1 TEX DEN I&75 A.M y BUT. OF AT $9 III N ELEV = ]0,]0 1 a y III I EI(li i ENTER F I r �1 &�I I BOE OF PIT I \I SEEN. - 7070 1 GARB CUT- 11 EEL N] I L. -- I9]0 I V 7e70 F.F.E. I80 01 AO 1 MAIN STACKING �F 11 1 Ns1E >V$ 11 1890 1 1 7960 LOW m1 III ] NO 190 AS 0 a < =/ �i Ax nn GRADING, DRAINAGE & EROSION CONTROL PLAN GREASE MONKEY LOT 1, REPLAT LOT No. 1 OF COUNTRY CLUB CORNERS THIRD RUNG A PLANNED UNIT DE0OPMENT IN THE CITY OF EMT COLLINS, COUNTY OF LARIMER, STAR OF COLORADO {� } GRADING & DRAINAGE NOTES R / I. ALL EXISTING TOPOGRAPHIC INFORMAIM TAKEN FROM DRAWING 10 OF 13. 'BIG '0PRE STORE' (DATED 05-16-996), PREPARED BY �O LANDMARK ENGINEERING, LM f. ALL CURB ELEVATIONS ARE FLEXURE UNLESS NORD OTHERWISE. FINISHED WALK AND CURB ELEVATONS SMALL BE 6' ABOVE FINISH PAYMENT UNLESS NOTE OTHERWR NORD. PROPOSED ELEVATORS ARE SHOW' TO THEM PAVEMENT OR GRADE. LANDSCAPE AREAS IMP SHALL BE ROUGH GRADED TO 6 BELOW TOP OF WN%s AND CURBS. 3, CONCRETE PAVEMENT, SDEWAK, CURB & GOTTEN TO BE REMOVED (IF APPLICABLE) SHALL BE SAWCE CONTRACTOR SHALL REMOVE TO IR R S IB NEXT JOINT IF SAW.UT 15 W1MIN 5 EMT BE A JOINT. 1 4 ALL FILL AREAS SHALL BE SCARIFIED UGHMINCHEs ANC RECCMPACRD TO 95% OF STANDARD PROCTOR DENSITY WM A MOSTJRE OPTIMUM, UNLESS OMERMS DIRECTED BY ME ENGINEER. LOOSE THICKNESS OF EACH LAYER OF N FEET RLLCONTENT PAVED D 95% OF STANDARD INCHES. AREAS TO BE PANED SHALL BE SCARRED AND MAT RILL SHALL SH UL BE FILL MATERIAL SHALL VIOL EXCEED El ( CEMENT THE GEOLUC NI 0[II = 10 R. %RCCTOR DENSITY YAM A MOISTURE CCNIFNi 12S FROM OPTIMUM UNLESS DIRECTED OTHERWISE BY THE OOTECNNICAL ENGINEER. 5, All MATERIALS AND WORKMANSHIP SHALL BE SUB£CT TO INSPECTION BY ME CITY BE R COLLINS ENGINEERING OIN90N. ME CITY RESERVES ME RIGHT TO ACCEPT OR REJECT ANT SUCH MATERIALS AND WORKMANSHIP MAT DOES NOT CONFORM TO ITS STANDARDS AND SOECIFK:ATONS - GRADING DRAINAGE & EROSION CONTROL LEGEND 1, IT IS ME CCMTBACTOR'S RESPCN9&UTY TO NOTIFY THE OMER / OWNER'S REPRESENUTY OF ANY PROBLEM(5) IN CONFORMING TO 7- APPROVED PLANS FOR ANY ELEMENT OF ME PROPOSED IMPROVEMENTS PRIOR TO ITS CONSTRUCTION - - -$'U- --- - EXISTING CONTOUR L NRRVAL) ]. CONTRACTOR MUST SCOPE (CUT) ASPHALT i0 FULL DEPTH IN A STRAIGHT LINE BEFORE BEGINNING EXCAVATION. ALL SAW CUT EDGES C ' EXISTING PAYMENT WILL BE CLEANED AND COATED WTH RC -BOP OIL PRICK TO PLACING NEW PAVEMENT ADJACENT TO ME EXISTING EXISTING INDEX CONTOUR (S INTERVAL) PAYMENT ---(e!Y & EXCEPT WHERE OTHERWISE PROVIDED FOR IN THEY BANS ME COLORADO DEPARTMENT OF HIGHWAYS STANDARD SROi1CATON5. UR: ��— PROPOSED CGNTWP EDITION. SHALL APPLY, +]&]5 PROPOSED SPOT (ROUE - PAY T BEVATON 9. 4R UES WTHN' ME CRY CREEK 100-YR RMO RAIN, IOU-YR FLOOD ELEVATION AT BUILDING - ]G )S SIR SILT SILT FENCE FREEBEWRD - 1.5 MINI" FINISH FLOM ELEVATION - ]R, 2 BARN BOUNDARY EROSION CONSIR MON PLAN NOTES ® ME CK PORT 1. ME CRY OF FORT DOLLAR STORMWATER UTUTY EROSION CONTROL INSPECTOR MUST BE NOTICED AT LEAST N HOURS PRIOR TO ANY 0o - I'M TOO L RUNCBE(Cls) CONSTRUCTON ON MIS SITE. 0 P = D25 10 A RUNOFF (ch) 2. ALL REWIRED PERIMETER SILT FENCING SHALL BE INSTALLED EEM TO ANY LAND gSMRgNG ACTMTY (STOCKPILING. STRIPPING, MANKIND, ETC.). ALL OMER REWIRED EROSION CONTROL MEASURES SHILL BE INSTALLED AT ME APPROPRIATE TIME IN ME CONSTRUCTIUN FLOW MARCUM SEQUENCE As INDICATED IN ME APPROVED PROJECT SCHEDULE, CONSTRUCTION PLAINS. AND ERD9aN CONTROL REPORT. 3. PPE-OSMRBANCE VEGETATON SHALL BE PROTECTED AND RETAINED WHEREVER POSSIBLE. REMOVAL ORDISTURBANCE OF EXISTING C BASIN NO. YGELATON SHALL BE LIMITED TO ME AREA REQUIRED FOR IMMEDIATE CONSTRUCTION OPERATIONS, AND FOR THE SHORTEST PRACTICAL PERIOD OF TONE. a.aD AREA (AC) A ALL SOLE EXPOSED DURING LAND DISTURBING ACTIVITY (SLIPPING. GRADING UTILITY NL, ETCJ SHALL VE MULCH, METE PERMANENT BY RIPPING OR DOU NC ALONG UND TQURS UNTIL MV6H, YCETATCN, OR OTHER BE KbT A ROUGHENED UNTILSATED,, LAND C LLED NO REE WAY SHALL REMAIN EXPOSED BY LAND ON CONTROL IS INSTALLED. NO SHIR IN AREAS WARE PROJECT SLEET RIGHTS RARY R DIST ACANRY FOR MORE .)II THIRTY DAYS BEFORE REOUIREO TEMPORARY OR PERMANENT EROSION CONL0. (E.C. SEEDAMING SEED/LIVLCH, LANDYA%NQ ETC.) IS INSTALLED, UNLESS OMFRWSE APPROVED BY ME siCRMWAIER UTULY. D, �— 5. ME PROPERTY SHALL BE WATERED AND MANTANED AT ALL TIME S DURING CONSTRUCTION ACTNTES SO AS TO PREVENT WIND -CAUSED EROSION. ALL LAND DISTURBING AERATES SHALL BE IMMEDIATELY DISCONTINUED WREN FUGTVE DUST IMPACTS ADJACENT PROPERTIES, AS DETERMINED BY ME PT( OF FORT COONS ENGNEEIING DEPARTMENT. 6, ALL TEMPORARY (STRUCTURAL) EROSION CONTROL MEASURES SHALL BE INSPECTED AND REPARED OB RECMSMUCTED AS NECESSARY AFTER EACH RUNOFF EVENT IN ORDER TO ASSURE CONTINUED PERFORMANCE CL THEIR INTENDED FUNCTOV. ALL RETAINED SEDIMENTS. PARTWLARLY THOSE ON PANED ROADWAY SURFACES, SHARE BE REMOVED AND OWOYD OF IN A MANNER AND LOCATION s0 AS NOT TO CAUSE THEIR RELEASE INTO ANY DRAINAGEWAY I. NO SOL STOCKPLE SHALL EXCEED TEN (10) FEET IN HECHT. ALL SOL STOCKPILES SHALL BE MERGED FROM SEDIMENT TRANSPORT BY SURFACE ROUGHENING. WARRING, AND PERIMETER SILT FENCING. ANY SO. STOCKPILE REMAINING AFTER 30 DAYS SHALL BE SEEDED AND MULCHED. 8. CITY ORDINANCE PROHIBITS ME LADING, DROPPING. OR REPORTING OF SOLD OR ANY OTHER MATERIAL ONE CITY STREETS BY OR FROM ANY VEHICLE. ANY INADVERTENT OEPOSRD MATERIAL SHALL PE CLEANED IMMEDIATELY BY ME CONTRACTOR, 9. SITE SPECIFIC EROSION CONTROL MEASURES WILL CONSIST OF A SILT FENCE AS SHOWN, ROUGHENING BE DISTURBED SOILS AND ADDING HAY MULCH TO ALL PROPOSED LANDSCAPE AREAS. DURING CONSTRUCTION. GRADE SITE MWARDS SET FENCE. EROSW CONTROL MEASURES TO ROMAN IN PLACE ME MARCH BE ME CONSTRUCTION PROJECT �w a Y[A3 OR T LD VERIFY LL E G ME AQ .&IIAM BY ROPDSED axs E��D� 'r� OR OF DI E CIE L , - KRNSRORTR &PDLK D V = i ,.M TPL J 'P 1300) � «13, Wts1N • In C� ,,OR TAS, B �u � � 216 161h street SITE Suite 1100 • �� Denver, Co. 80202 28• (303) 534-1660 1500 North College Avenue ° Fort Collins, CO 00�j SCALE I = 10 DRAWN BY KS ol�B.KI TOO DAM 06/15/90 ORDERED BY A Nod MaI NCINIT4 DHwct Man er — DISTINCT NO. SA MAP Aye op NAME A BENCHMARK Mqr Der En9menM9 — (/� -6b' Mqr. GPORm Itrig 1 — N Om OF I IS OUR wmceL THE onnx 15 DF. PH uP,Felnq V �1. COLLEGE Is AVENUE A EAST « THE INIERVcATN — N0. EOF IEVATp OF BR2L@ FEBBISRfCWE CNM AT IH �rM]U Reg- YFe-P,pHmi WT vu on [ IFS MI[IAYI btlT