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HomeMy WebLinkAboutDrainage Reports - 08/03/2006I ' City of Ft. Cold Ap roved plans p'YtOPEttTy �F APProved By . ' "RT CA�+U�i3Ti Date S -3 -C /� FINAL DRAINAGE AND EROSION CONTROL STUDY HARMONY OAKS FINAL DRAINAGE AND EROSION CONTROL STUDY HARMONY OAKS Prepared for Lyman Davidson & Dooley, Inc Architects 3944 JFK Parkway, Suite B Fort Collins, CO 80525 Prepared by North Star Design 700 Automation Drive, Unit I Windsor, Colorado 80550 (970) 686-6939 February 28, 2006 Job Number 199-01 1 North Star fir. design Inc 1 1 1 February 28, 2006 Basil Harridan City of Fort Collins Stormwater 1 700 Wood Street Fort Collins, CO 80522-0580 1 RE Final Drainage and Erosion Control Study for Harmony Oaks Dear Basil I am pleased to submit for your review and approval, this Final Drainage and Erosion Control Study for Harmony Oaks office building I hereby certify that this report for the drainage design 1 was prepared in accordance with the criteria in the City of Fort Collins Storm Drainage Manual 1 I appreciate your time and consideration in reviewing tlus submittal Please call if you have any questions 1 1 1 1 1 1 1 11 700 Automation Drive Unit I Windsor Colorado 80550 970 686 6939 Phone 970 686 1 1 88 Fax 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Yam\ : *0 wlelelel I X Il l I TABLE OF CONTENTS 1 GENERAL LOCATION AND DESCRIPTION 11 Location 12 Description of Property 2 DRAINAGE BASINS AND SUB -BASINS 21 Major Basin Description 22 Sub -Balm Description 3 DRAINAGE DESIGN CRITERIA 31 Regulations 32 Development Criteria Reference and Constraints 33 Hydrologic Criteria 34 Hydraulic Criteria 4 DRAINAGE FACILITY DESIGN 41 General Concept 42 Specific Flow Routing 43 Drainage Summary 44 Variance Requests 5 EROSION CONTROL 5 1 General Concept 6 CONCLUSIONS 61 Compliance with Standards 62 Drainage Concept 7 REFERENCES APPENDICES A Vicuuty Map B Hydrologic Computations C Detention Pond Sizing D Figures and Tables E Erosion Control Calculations ui ui 1 1 1 1 2 2 2 3 3 3 4 4 Fi ' 1 GENERAL LOCATION AND DESCRIPTION 11 Location ' This site is located on the north side of Harmony Road between Boardwalk Drive and JFK Parkway in Fort Collins This project is located in the Southeast Quarter of Section ' 36, Township 7 North, Range 69 West of the Sixth Pnncipal Meridian, in the City of Fort Collins, Lanmer County Colorado See the location map in Appendix A The project is bounded on the north and east by The Pier Condominiums, on the west by Iexisting County residential and Home Depot and on the south by Harmony Road 12 Description of Property ' The entire project consists of approximately 0 9 acres of land A house and several I outbuildings exist on the site and the site slopes to the southeast at slopes ranging from 1 to 15 percent A small portion of the north end of the site drams to the existing drainage swale on the north IThis project will include demolishing the existing structures on site and construction of a ' three-story office building with associated parking and drives Detention will be provided in the southeast comer of the site The pond will outlet to the existing curb on Harmony ' Road on the south property line 2 DRAINAGE BASINS AND SUB -BASINS 21 Major Basin Description IThe proposed development lies within the McClellands-Mail Creek Drainage Basin It is ' proposed that the detention area on site release at the 10-year historic runoff rate for the site This release rate was determined based on meeting with City staff and the inability to obtain required easements to allow the runoff to flow north through the Pier ICondominiums as the Master Plan shows ' 22 Sub -basin Description This site is located in Basin 396 of the Master Drainage Plan which includes all of the 1 Pier Condominiums and several other adjacent properties This basin is detained in Pond ' 496 (which is actually several small detention ponds) and releases into conveyance element 88 on the east side of Boardwalk Drive The routing of the runoff from tlus site ' as proposed with the Master Plan is not possible without an easement from the Pier Condominiums This easement was not able to be obtained therefore the routing is proposed to be modified from the Master Drainage Plan and be routed to Harmony Road 3 DRAINAGE DESIGN CRITERIA 31 Regulations ' This report was prepared to meet or exceed the City of Fort Collins Storm Drainage ' Design Criteria Manual" specifications Where applicable, the criteria established in the 'Urban Storm Drainage Criteria Manual" (UDFCD), 1984, developed by the Denver ' Regional Council of Governments, has been used 32 Development Criteria Reference and Constraints ' The runoff from this site has been routed to the proposed detention pond on site Detention and water quality facilities will be provided for the site in a pond that has retaining walls on 4 sides and a grassed bottom The maximum height of the walls surrounding the pond is 3 3 Where pedestrian traffic is near the walls, handrails will be provided 33 Hydrologic Criteria ' Runoff computations were prepared for the 2 and 10-year minor and 100-year major storm frequency utilizing the rational method ' All hydrologic calculations associated with the basins are included in Appendix B of this report Standard Form 8 (SF 8) provides time of concentration calculations for all sub - basins Standard Form 9 (SF-9) provides a summary of the design flows for all Sub - basins and Design Points associated with this site Detention volume was calculated based on the 10 year historic release rate which was established based on meetings with the City of Fort Collins Stormwater staff The FAA ' method for detention pond sizing was utilized to determine the required volume Water 2 I 1 1 1 1 4 1 1 1 1 1 1 1 quality volume was calculated using the method recommended in the "Urban Storm Drainage Criteria Manual 34 Hydraulic Criteria All hydraulic calculations within this report have been prepared in accordance with the City of Fort Collins Drainage Criteria and are included in Appendix C of this report DRAINAGE FACILITY DESIGN 41 General Concept The runoff from this site will be collected in the on site curb and either be conveyed to the proposed inlet in the southeast comer of the site or be conveyed to the proposed detention area in the southeast corner of the site The proposed storm pipe will convey this runoff to the detention pond also This pond will attenuate the runoff to the 10 year historic runoff rate and will discharge the water to the existing curb along the south side of the site This pond will also provided extended detention for water quality No off site flows enter the site from adjacent properties and only small portions of the landscape areas on the west north and east will be released undetamed 42 Specific Flow Routing The site has been divided into two basins and a summary of the drainage patterns within each basin is provided in the following paragraphs Basin 1 contains the east half of the site including the east half of the parking lot and the detention basin The runoff from this basin is conveyed via concrete pans and curb & gutter to a curb opening in the southeast corner of the parking lot The runoff then enters the detention pond and is detained before being released to the existing north curb of Harmony Road Basin 2 contains the building and the west half of the parking lot The runoff from the roof is collected in the downspouts and conveyed underground to the storm pipe Runoff from the parking lot is conveyed overland and in a concrete pan to a proposed inlet and 3 into the storm system This system then conveys the runoff to the detention area This ' storm system will be designed with the final construction drawings for the site 43 Drainage Summary ' The City of Fort Collins will be responsible for maintenance of the existing storm drainage facilities located within the right-of-way The drainage facilities located outside of the right of way (including the detention pond, detention outlet pipe and storm system) will be maintained by the owners of the site ' 44 Variance Requests A variance is being requested to allow this site to release at the 10 year historic rate into Harmony Road This variance is being requested because the owner was not able to obtain an easement from the property owner to the north A variance is also being requested to allow for a freeboard of 0 6 rather than the required 1 0' The detention pond depth is linuted by the existing elevation of Harmony Road which the site discharges to The maximum amount of detention is being provided and ' this reduction in freeboard should not cause inundation of any building 5 EROSION CONTROL 51 General Concept This site lies within the Moderate Rainfall and Wind Erodibihty Zone per the City of Fort Collins Zone Maps The potential exists for silt movement from the site and into the existing storm system during construction Potential also exists for tracking of mud onto ' existing streets which could then wash into existing storm systems Silt fence will be provided around the perimeter of the site a construction entrance will be provided at the exit from the site and wattles will be provided around the east end of the storm pipe The incorporation of these best management practices will reduce the amount of sediment leaving the site during construction ' 6 CONCLUSIONS 4 into the storm system This system then conveys the runoff to the detention area This ' storm system will be designed with the final construction drawings for the site 1 43 Drainage Summary ' The City of Fort Collins will be responsible for maintenance of the existing storm drainage facilities located within the nght-of-way The drainage facilities located outside of the right of way (including the detention pond, detention outlet pipe and storm system) will be maintained by the owners of the site 1 44 Variance Requests - A vanance is being requested to allow this site to release at the 10 year historic rate into Harmony Road This vanance is being requested because the owner was not able to ' obtain an easement from the property owner to the north A vanance is also being requested to allow for a freeboard of 0 6 rather than the required 10 The detention pond depth is limited by the existing elevation of Harmony Road which the site discharges to The maximum amount of detention is being provided and ' this reduction in freeboard should not cause inundation of any building ' 5 EROSION CONTROL ' 51 General Concept Tlus site lies within the Moderate Rainfall and Wind Erodibility Zone per the City of Fort ' Collins Zone Maps The potential exists for silt movement from the site and into the existing storm system during construction Potential also exists for tracking of mud onto existing streets which could then wash into existing storm systems Silt fence will be provided around the perimeter of the site, a construction entrance will ' be provided at the exit from the site and wattles will be provided around the east end of the storm pipe The incorporation of these best management practices will reduce the amount of sediment leaving the site during construction 1 4 1 I 6 CONCLUSIONS 1 61 Compliance with Standards All computations that have been completed within this report are in compliance with the ' City of Fort Collins Erosion Control Reference Manual for Construction Sites and the Storm Drainage Design Criteria Manual 62 Drainage Concept ' The proposed drainage concepts presented in this report and on the construction plans adequately provide for the collection and conveyance of runoff to the detention area ' Conveyance systems will convey the stormwater flows to the pond as required The on site storm system will be a privately owned and maintained system and will not be designed to the muumum City requirements 1 If, at the time of construction, groundwater is encountered, a Colorado Department of ' Health Construction Dewatermg Permit would be required ' 7 REFERENCES 1 City of Fort Collins "Storm Drainage Criteria Manual", (SDCM), dated March 1986 2 Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria Manual' Volumes 1 and 2 dated March 1969 and Volume 3 dated September ' 1992 ' 3 McClellands Creek Master Drainage Plan Update by ICON Engineering, Inc dated November 30, 2000 1 5 11 [] 1 1 11 1 u 1 APPENDIX A VICINITY MAP A No Text I 1 J 1 1 [1 1 APPENDIX B HYDROLOGIC COMPUTATIONS 19 cc ( () 0 LL /) \/ j( \\ z \ � � / 'a )k z2( (�m EE uBee 0o SmSo )I ®k ®a= ƒ r°0)§§N �§ CDc \ � � ) # §0 0< §!k 2 ! \a: f77 7§f � it< `E ! 0< §9§ m )§k §!! 9 §CL \ e § mo ak Cc o \k\[ 3 CIL 2 \ �0" ( \§f] \«e%@f H It 'e 7rt k2 j° j % 1 1 1 1 1 1 1 1 1 i 1 1 1 1 1 1 1 to Q' 0 0 LL z N o Z yo0 Q G Q N Z W U z 0 0 LL O LULU C N k O z O O x � a u U W O O F O U as Ufa Y i W R' z "' E� NNN LL O i O C a r m N � .. 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O z Y Q a Ix oQ O W 2 >. � O W � v J Q z O CIO x i' p c O O u U � y rn z O p o U p F O O A d a° n c y n o g o m y f V1 O W Ix H F O � N O O_ N LL' dV LU O � > E m c g rd o LL U Q N O m t D U C t0 O f0 E n n n U o 0 0 0 U Q N N M < e� D f0 W m C O O O LL LL z c m N JX U C ~ Q y W c 9 W C C N O C a N p a o Si a` w 2 U It o w o N c � y L � 01 U m f0 h U U U GGo N O Q N V m 7 — (0 O N O d C Q ) w C o C Co CL II II It M QLL U 0 O U a9i II N C C W O z 0 O LL LL O z M Y a� a O } O W � v J Q z _O Q O to O r u U U € r W (0 c O o z00F 0 U a U O . acwUC Y Y d c wac K y 0 m 0 OU _o Ymi w O c Y E a 5 2 m a 0 U o omumi � m m rn rn m c E rn m rn r U C_ O o O E 0 N N U rnoo .fDi U Q l��I l7 f0 t0 m O O O O LL LL = m W J F ¢ � ca W K O m o a` w 2 7 U LL 0 E 0 w N � N U N Q) C — N O/ « N % L C c t_Un O N Q � C N o Y O C a d :3 �O m m O 0 N a N c m c F 0 z 0 d O LL I 1 1 1 �l 1 1 i 1 1 I 1 1 1 1 1 1 i APPENDIX C DETENTION CALCULATIONS 7 I 1 1 i 1 1 1 1 m CO U CD CD0 O r O r O W � II II II II II � -0o Q a Y W o U a U Ci F a 1 W � -9 O m J Q Q 1 O> W W m O o Q oLL to 0 W LL W G M C O t h € 1 - 5 x- �z o U o 0 LL II Q_ O Q U CY 1 U o V > > V! ;, O Q F F o c F cc 1 u 'o a c W, 0 a W N a a.0A C� m �.' r O CO O CD OOrr00 0 0 0 co M 1` a r, 0000000 CO 1n M N r a O 0CD Np C l0 O O O O O O O O O O O O O O O O O O p N m 10 w L N (p M Cn O O r V In (p Ln f� CA CO CO N O N M CA r O In r V r f0 CA co M O CC) (A O �' 0 "" h r 0 N M M r V N N N q O M r M M N LO N N N CO r In r r r n L r n to m O .0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O p >`�' T NVOrT N sY N CO, N " N M N Co) M ,0 M�'7 CCOO Oco Cn LO 00 CO LO CO CO N CO � r, N I-- O n Cn O Cn O 0 CO N N O O r r CA M 00 IT _ r. Cn CO O M 4 r, M N CA CA M CA F- r Co N CO I� h M h M CO CA CO O O O CO O N N Cl) M co IV M � Cn O CO CO CO CO CD CO CD CO f.- h Ih t, h t. O 4A a CO r h O l(7 r T CO M r 0 0 CD 00 CO CO , V v CO Cn M M N N r r r r r T r 0 0 0 0 0 0 l0 �' Cn NONIt MCO COOOOt- CO C N L 0 r W CO I-N w IT O W I- CO a M N 1100 w.�C.. 0 r, LO 'Ct M M N N N r r r r r r T r r r 0 E Lo 0 0 N 0 CO O ct O LO O CO O r� O CO O T N MT OW r, W T T r r r T r r r 0 1 r I (0 a� rn co m c ca c m V1 } t0 d C N O N N �p OO N p M C cor. C b 0 m 'm a) =% cts O A A U r.a EO o� c� eaeo x 3 a z ` U �n aD a, a� E E 2 o O i O N w w T z a°W O co `_cc rFF. L a c pwp� o y cc -7�U LL Z� `" o a �p C LL O cr O w N i ' m Q v O O 3 r � G V N Q � 3 O O N 0 Q 0 O N (A I 0 m C LL O z "E ° w a E m F � = o Z O p W z In a 1w T v 0 0 0 c a) � 3 3 Z O O O O c. E�� O N O O N N 0 O] cc N > c -o Q` ° ° aoi c N 0)4t n. Of U)q)o cc co L 2 N a o M e 1 1 1 i 1 1 1 1 1 i 1 1 1 1 1 1 1 1 1 PROPOSED DETENTION POND STAGE STORAGE TABLE (100-YEAR) LOCATION Harmony Oaks PROJECT NO 19901 COMPUTATIONS BY ppk SUBMITTED BY North Stu Design, Inc DATE 8/2/05 100 yr Detention Volume Required = 0 099 Water Quality Capture Volume Required = 0 024 Total 100 yr Volume Required = 0 123 WQ Volume 100 year HWEL Stage (ft) Surface Area W) Incremental Storage (ac ft) Total Storage (ac ft) 501225 0 5013 1705 0 010 001 50,1335 1739 0 014 0 024 5014 1803 0 040 005 501490 5682 0 074 0 124 501500 6113 0 086 014 CfifiLk�� " -rt _a. 1 � . .]Al:,at J6AiA . .._ I - —,I _ � . PROPOSED DETENTION POND Detention Pond Outlet Sizing (100 yr event) ' LOCATION Harmony Oaks PROJECT NO 19901 COMPUTATIONS BY ppk ' SUBMITTED BY North Star Design, Inc DATE 8/2/05 ' Submerged Orifice Outlet release rate is described by the orifice equation Qo = COAO sgrt( 2g(h Eo)) where Qo = onfice outflow (cfs) Co = orifice discharge coefficient g = gravitational acceleration = 322 fus A0 = effective area of the orifice (W) Eo = greater of geometric center elevation of the orifice or d/s HGL (ft) h = water surface elevation (ft) Qme = 070 cfs ' outlet pipe dia = D = 150 in Invert elev = 501225 ft Eo = 501242 ft ' h = 501490 ft 100 yr WSEL Co= 061 ' solve for effective area of orifice using the orifice equation Ao = 0 091 ft` 131 m` ' orifice dia = d = 408 in Check orifice discharge coefficient using Figure 5 21 (Hydraulic Engineering) ' d I D = 027 kinematic viscosity v = 1 22E 05 ftz/s Reynolds no = Red = 4Q/(pdv) = 2 15E+05 ' Co = (K in figure) = 061 check Use d = 41 in A o = 0 092 ft ` = 1320 in Q o = 071 cfs I h PRELIM Pond_OPT2 As Emergency Overflow Spillway Sizing LOCATION Harmony Oaks PROJECT NO 19901 COMPUTATIONS BY ppk SUBMITTED BY North Star Design DATE 2/28/2006 Equation for flow over weir to _ of berm b Q = CLH'n 4 ♦ spill elevation where C = weir coefficient = 26 ♦_ L H = overflow height p 100 yr WSEL L = length of the weir — The pond has a spill elevation 0 0 ft above the maximum water surface elevation in the pond Spillways will be designed with 0 5 ft flow depth thus H = 05 ft Size the spillway assuming that the pond outlet is completely clogged South Pond Qioo = 653 cfs Spill elev = 501500 ft Min top of berm elev = 501550 Weir length required L= 71 ft Use L = 10 ft v = 093 ft/s PRELIM Pond_OPT2 As 100 yr WSEL = 501490 ft I 11 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 APPENDIX D FIGURES AND TABLES 1 5ME TNR6 75 T71 Mil 1111 1 M-11I.-MMIRFUS V AIMUM Prepare the City Of Ft Corins PRO.EC- 4t5 ORA" C" DESKYED CYN a*c� Djw Cit7 of Fort C No Text U] I 1 City of Fort Collins Rainfall Intensity -Duration -Frequency Table - for using the Rational Method (5 minutes — 30 minutes) Figure 3-1a Duration (minutes) 2-year Intensity in/hr 10-year Intensity in/hr 100-year Intensity in/hr 500 285 487 995 600 267 456 931 700 252 431 880 800 240 410 838 900 230 393 803 1000 221 378 772 11 00 213 363 742 1200 205 350 716 1300 1 98 339 692 1400 1 92 329 671 1500 1 87 319 652 1600 1 81 308 630 1700 1 75 299 6 10 1800 1 70 290 592 1900 1 65 282 575 2000 1 61 274 560 21 00 1 56 267 546 2200 1 53 261 532 2300 1 49 255 520 2400 1 46 249 509 2500 1 43 244 498 2600 140 239 487 2700 1 37 234 478 2800 1 1 34 1 229 469 2900 1 32 225 460 3000 1 30 221 452 11 APPENDIX E EROSION CONTROL CALCULATIONS I [1 1 1 F- C O LL C C t� PAGE 23 1 O I CCLnL7� ! 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I C tp 1-1 rI n n g q p p q d p p d d d C d C d= C6 CJ CC CJ 1 r�rn11.1-1r-Ir%lrl nnnnnnnnnl-Innn n.n 1 LP) 1 C%O Ctp r-Iddn nr-I tC tO Ln C C m M N N C1 tC :Z.- Cif tC I C I O C'V N N C4 N N N N N N N N N N N CV N N N. * .r ..I .--L O O 1 n n n nn n n n n n n n n. ran 1 S I 13 H� I C O C O O O C O O C O O C O O O C C O O O 0 0 0 0 0 1 Ot^F-- 1 00 C C C COO OCOOCOOOOCOCOOCG 00 I JZLL 1 .--IN cn C'L'1tCngON 0MCL'1to1.1 un LnCLn O i J 1 TABLE 5.1 I _ » � _ \ \ "noJ _a `` / / / \\\ \ \ u / k / / \ j z ) / 3 ` < 2 / j jE !\ ?) $\ §§ \ � 3 2� ( LU w z �! m@ \3; � §§ � � �u /0 rz ,u 2�£ \�\ \§\ (\® zzm }/( co \\\ k /\ /00 §\ ) r , 00 /ƒQ gQ200 Q\« cc r a® g® =2 )§am -; )j)S+ P. m 1 1 1 1 North Star Design 700 Automation Drive Unit I Windsor CO 80550 EFFECTIVENESS CALCULATIONS PROJECT Harmony Oaks STANDARD FORM B COMPLETED BY PPK DATE 28.Oct 05 EROSION CONTROL CFACTOR PFACTOR METHOD VALUE VALUE COMMENT BARE SOIL 100 100 SMOOTH CONDITION ROUGHENED GROUND 100 090 SEDIMENT BASIN 1 00 050 ROADS/WALKS 001 100 GRAVEL FILTERS 100 080 PLACED AT INLETS SILT FENCE 100 050 STRAW MULCH 006 100 ESTABLISHED GRASS 008 100 STRAW BARRIERS 100 080 EFF=(1-C P)•100 MAJOR SUB BASIN AREA EROSION CONTROL METHODS BASIN BASIN (Ac) 1 032 BARE SOU, 0 04 Ac ROADSIWALKS 023 Ac STRAW MULCH 000Ac ROUGHENED GROUND 0 05 Ac ESTABLISHED GRASS 0 00 Ac NET C FACTOR 029 NET P FACTOR 038 EFF = (1-C•P)• 100 = 89 1 / 2 034 BARE SOIL 005 Ac ROADSIWALKS 0 19 Ac STRAW MULCH 0 00 Ac ROUGHENED GROUND 0 10 Ac ESTABLISHED GRASS 0 00 Ac NET C FACTOR 045 NET P FACTOR 037 EFF = (1-C'P)* 100 = 83 3 / TOTAL AREA = 066 ac TOTAL EFF = 86 1 / REQUIRED PS = 75 4 /o Erosion As 2of4 CONSTRUCTION SEQUENCE Project: Harmony Oaks Date: October 28, 2005 Indicate with bar line when constructions will occurr and when BMP's will be installed/removed in relation to the construction chase CONSTRUCTION PHASE (Week/Month) 1 2 3 4 5 6 7 8 9 10 11 12 Grading (include Offsite) Overlot Detention/WQ Ponds Swales, Drainageways. Streams Ditches Pipeline Installation (Include Oftsite) Water Sanitary Sewer Stormwater Concrete Installation (include Offsite) Area Inlets Curb Inlets Pond Outlet Structures Curb and Gutter Box Culverts, Bridges Street Installation (Include Offsite) Gradiing/Base Pavememt V Miscellaneous (include Offsite) Drop Structures Other (List) BEST MANAGEMENT PRACTICES Structural Silt Fence Barriers W7 77— 71 Contour Furrows (Ripping/Disking) Sediment Trap/Filter Vehicle Tracking Pads -'s-T 15TTT 77711a Flow Barriers (Bales, Wattles, Etc) UZI, M Inlet Filter Sand Bags Bare Soil Preparation Terracing ng Stream Flow Diversion Rip Rap Other (List) Vegetative Temporary Seed Planting Mulching/Sealant Permanent Seed Planting Sod Installation Nettings/Blankets/Mats Other (List) Cost Est 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 EROSION CONTROL COST ESTIMATE Project Harmony Oaks Prepared by PPK ITEM IQUANTITY JUNIT COST/UNIT ITOTALCOST Silt Fence 700 LF $3 $2 100 Wattles 1 EA $150 $150 Gravel Inlet Filter 0 EA $150 $0 Construction Entrance 1 EA $550 $550 Subtotal Contingency (50%) Total $2 800 $1 400 $4 200 CITY RESEEDING COST Reseed/Mulch 1 0 66 ACRE 1 $775 $512 Subtotal Contingency (50%) Total $512 $256 $767 EROSION CONTROL ESCROW AMOUNT $4 200 Page 4 D r Exlsnic emminc� I PROPERTY B UNOARY� I I II I � I I I I i 1 I I ' I mAsn ENCLOSURE_ osuRE _ _ _ _ _ _ _ -- —_--I_________—_____J \ \ PAOPM" Ba NDUARY _ _ I— ,\ -PIT it I) \ \dame I in I b by 41\\ \ ,Rug \ it it \ it fir 1 I `\\�I 1 1 ' o.de a �I 1 IL Ri Sir ;' r by: fir PROPOSED 81.1ILDi 1 d 11V _ we wwwwwwwww _ wwwwwwwww iiiiJ _ _ 111_ iLei ^_� _i — _ �. MNDARY T"MRQUALITYanET sTRucnME L,L_ \N \ -- 20 10 0 20 40 SCALE: To AS 20' QME POINT BASH CRITERIA 20 a 5 M RUNOFF COEFFICIENT AREA IN ACRES rtow DIRECTION mmmoommmm BASIN BOUNDARY Oj(— SAT rtNGE O- CONSTRIICTM ENTRANCE ee^ OOom�, WATRES PAWOMD STCPM PIPE m RARED END SECnM --�Y905---- EXISTING 5CONTOUR EVSRI V CWTWR —4805— Pgwmo 5' CCa RIPOEOSED I' CONICUR DRAINAGE SUMMARY TABLE DESIGN POINT I AREA DE51C. I AREA ACRES I C2 C100 Tc (2) NIN Tt (100) YIN 0 (2 CFS 0 (IDO) CFS 1 1 ULN: 0.)6 0.97 5.6 5.0 0.6) 3.05 2 2 0,34 0,93 LED 5.0 5.0 0.90 1.39 DET11114i POND SI,MAIn11Y 100 YR DE TON REWIRED 0.099 AC. FT. WE VWUME EWIRED 1 0.024 ACTT. TOTAL WLUNE PRONDEO 0.123 Ai 1CO 1 0014.90 MAX RELEASE RATE 1 070 US HARMONY ROAD _ - — we — - — - — - — - — - — - — _ — - — - STANDARD ER090N AND SEDIMENT CONTROL CONSTRUCTON PLAN NOTES entra F mpRN D al tatY- (24) n M Play to err emStMCI n On this Fleet 2. 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By b,pv ce of 'ngnum olmcs eery iw 12) n9 a ly msoeeahve solnnen Y _ i e a rairM w rvcmeWdM ao necnawY In ) M B. wsM,,SO<. 1My'r iuNhM Mwttl . .nyn F pD.e la m IN me ke ua D m 11«rb e W by een m mn m a a.w. C. mmmm be ale D. hoer IyiImYY .tmE4M for a.lwn;nm by a wyam erc Them m tatmu r m cmyn can" rmy,n new mmysW, The o.WyD✓ <holl be r..pyn.ale ly. the 0I<m OR Rune .mmyml It III eeeimml nna eron, rmr III ernny< IrFmirncly,e one Ic Imiilies. 01Fer D 4 ID wcm Ruda sholl'mm whet I ftla m my my. moler40 FOeverlenlly eepw tea Run 0.1161 a wts. anevol4a, v upl� rights 01 v0y, and mwv au a abeete and thwp m dw i d theat ly waF9 my. eAd U aged SWlmal. che Wr Inem m pmW mach wawa. sal be mme.ed ma aimo..e of m a mmn<r ma Isom m IS we m aww m<n .nxa �nw r "New If lb o ,I slur.<. enceld m DO) tat ha noie wl MUIN N.. Mod be p,ylxiM Imo eMFlml Wnyat by mix. rwa.eninq. .mmmq me DalmeW ,IN rmdnq. y wl Us Wro matp deal cathod If KID)• ma a :.I b yne rammed. 12, coprc IY 0I edmim peN al oa restated ma dwm uw IFee .11 x demo] upm [anpletlm 01 iM wyFl ma ovrve tumu.q them0nnemynce am 10 wet _ the ci ynaena ce Fi lu iwWy ct xpyrm Pe n Seattle (tops) m a toll n .mare to rack wa hc aim N discharge W Of mY root a M watch draa Ater mta a atde. but a sFin m0 atl a lr d dismiss of puf ulmbrm the 0.is ieude. Iittle, and xnca an my Slid 01 WPIboth rl le Vote, Will of tll Imes lati vhalew moerra m nmamrY to osmre a prop. ownlmnmen m e190 e F accv m Iota, sae, me rredml all be oe. 'MY Kim Y lotw Drha Ill wane.e m . a IOU t ook, Ir cFlats ANSI m<Wcrlm =t the e,w ,nth x tmetrettm m m mnae eymml m�y a.wx of perch to the bei.y 0 y q weWctim. It, mmdelim Fd Mla Na cant ale wehwl m0lsltl i� W narrowed me pr 0 ha hym IS, KIT w Nor Wmmt each not m Itllt ae Of the Idbm ving aVmmtiv"m elrtl by nma mMo WP, all stai oinee Fell the let, ve xHitienBY ata aHM, oe ev1 W by The W"w emFai,g tv. a br A. Bdx of Ruler Ilmmg B. OUT l0 *Oh� nax c. Nmg let prmete. D. Other Irc,i it nxMG IB. CmeiEmo in ins field m ant cmtrd mmwrm In o itk to What i, Won My them piers US O ww oa mPlmrmt Mlolmr meomre, are atr ,n rlete .. ae deeded by filet cnr. r CALL UTILITY NOTFICATON CENTER OF COLORADO 1a800.922=1987 CALL 2-BUTNESS DAYS IN ADVANCE BEFORE YOU DID GRADE, OR EXCAVATE DR WE MARKING OF UNDERGROUND MEMBER UTLI➢ES. City of Fort Collins. Colorado UTILITY PLAN APPROVAL APPROVED: — City E,pl CHECKED BY: _ Wale A Rslewtw THIRTY CHECKED BY: Stammtw lady CHECKED BY: PMs A RgwTlm CHECKED BY: Tmm Elylneer CHECKED BY: •-J N � N Decl 09omm 11 E1 m C `o_ owic �._ m OC oU11- Cba . CIDo. COO) 0 c Car Risk �D �3a11 z� 0 N W OC i m a Q- thyOR a u i o In o o` rA WE II SHEET 5 5 OF 7 199-01