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HomeMy WebLinkAboutSite Certifications - 09/26/2002CD Transportation Construction Management Development surveying Environmental Resources Ports/Airports Planning Water/ Wastewater E N T R A N C O 9/23/02 Stormwater Engineer Development Review Stormwater Utility City of Fort Collins 700 Wood Street Fort Collins, CO 80521 Re: Drainage Certification. City of Fort Collins Stormwater Utilities- STORMWATER RECEIVED SEP 2 6 2002 A'Kw I hereby certify that the drainage improvements associated with the Poudre Health Services District Building was constructed in general accordance with design plans and specification dated 10/17/01. If there are any questions regarding the design as built, please feel free to contact me at (970)221-3600. Respectfully Submitted, Stacy J Gowmg, PE Tt ?�a .i S Colorado Professional Engineer o. � For and on Behalf of Entranco, Inc. Z 345 East Mountain Avenue Fort Collins, Colorado 80524 Telephone 970 221 3600 Fax 970 221 9 33 SEP-19-2002 THU 08:00 AM HEATH CONSTRUCTION FAX NO. 9702212907 P. Ol HEATH Basil Hamden City of Fort Collins Stormwater Division Fort Collins, CO R.C. HEATH CONSTRUCTION CO. P.O. DRAWER H -141 RACQUE71E DR. FORT COLLIHS, CO 80522 (50524) (970) 221J195 FAR (970) 221.2907 RE: Pondre Health Services Construction (Permit # B010098) Dual 30" HDPE Pipe Installations Dear W. Hamden: September 19, 2002 Heath Construction has postponed the installation of the dua) 30" HDPE pipes that will go from the edge of Bristlecone Drive to the existing storm box. This work was postponed for technical reasons that have recently been resolved. Heath Construction will proceed immediately with the work. However, this work can not be completed by the Owner requested occupancy date. Heath Construction would like to establish an escrow for the value of this work plus a 25% contingency so that a Temporary Certificate of Occupancy can be obtained. The Work will be completed by October 31, 2002. The amount of this work is calculated as follows: Dual 30 HDPE LINE INSTALLATION ESTIMATE Costs per Boone Construction: $5,145 Pipe $1359 Beddingrock $6 45 ui ment Rental & on $706 Concrete & Flow Fill $1218 Trench Box $14 877 Total Construction Costs 3,719 Contingency $18,596 Total Escrow Requkement I have attached a breakdown of the costs for the Dual 30" line that were received at the beginning of the project from the Earthwork subcontractor for your review. Thank you for your time and consideration of this request. Respectfully erry W. Been Project Manager www.111"AlHCOR5TKUCTIO coM SEP-19-2002 THU 08:00 AM HEATH CONSTRUCTION W—mi-04-02 12.04P BO XCAVATINO INC FAX NO. 9702212907 970Z,2,40994 P. 02 P.O1 Boon Consuuctkm PO Box 270262 Fort CoUin& CO $0527 pw Rock Lquipmenr Corte Trench box TOTAL Boon Coior�, Tustin Boyd R C Heath Coasumlon Inc. Pondre lleath 9wviccs 30" Storm Sewer $5,144A7 $1,_358.92 $6,450.00 5705.88 $1.217.67 $14,976.94 DRAINAGE CERTIFICATION FORM Please fill out all applicable items in this certification form for single family, multi -family and commercial properties. Write "OK" for items checked or actual number checked in field. Use "N/A" for items that are not applicable to the property that is being certified. A. Drainage facilitice certification .1. Pond Certification -volume verification a. topographic records and volume, b, cross -sections and spot elevations -positive fall to pan. -side slopes -invert elevation -spillway elevation i -placement and size of riprap -side slopes -grading -orifice plate installation and size -compaction of berm -structural integrity of pond 2. Swales -location (are they within easement) -dimensions and cross-section verification -longitudinal slopes and side slopes -spot elevations -permanent erosion control measures ��Js (drop structures, riprap, etc....) .-tie-in to pipes, pans, curbs, etc.... -weir size (elevations, size, opening, etc...) -"`tom -available freeboard -landscaping infringement on swales 3. Pipes -size and type O« -slopes (as -built and comparison to minimum O YS 0.4% slope). -pipe capacity calculations if slopes are significantly altered l -invert elevations -installation and backfill material -cover -encasement and clearance from other utility lines close by �Q -joints 4. Concrete an Channels -size Q& -slope _OK -super elevation -cross-section f -thickness -elevations K S. Inlets -size and type -size of opening (or name of standard used) -grate elevation -invert elevation -box size 6. Cross vans -size -type -grade -elevation -cross-sectional depth -tie-in to curb and gutter 7. Culverts -size -type -invert elevation -headwalls 8. Underdrains -size -type -cover -backfill -geotextiles A �A AdA 4 a -cleanouts 9. Curb cuts -size -tie in to Swale, pipe, etc.... B. ,Certification of Grade Elevations Adjacent to Drainage Facilities: -minimum opening elevations -top of foundation elevations -comparison to 100 year WSEL's �K (Freeboard requirements and flocdplain issues) C. Certification of Erosion control Measures: 1. Permanent Measures: -Permanent vegetation (6" bare spots and weeds under control) pVL -riprap -riprap bedding �k -drop sections -sediment basins/water quality pondsQ -netting mats/blankets -mulching 2. Temporary Measures: -mulching -inlet filter installation -check bale dams -seeding and temporary vegetation -silt fence D. Site Cleanup After Construction -construction clean up -smoothing of ruts -reseeding E. Statement of Compliance This certification is signed and stamped and by signing this form the engineer(s) attests that to the best of his knowledge the as -built conditions of the drainage facilities are as. described in the above form and in the redlined plans enclosed. Failure to properly disclose all known information could result in the rejection of this certification and prevent the release of any Stormwater Utility holds on Building Permits and/or Certificates of Occupancy. F. Signature and Stamp by a Colorado Registered Profeeeional Engineer. Poudre Health Prepared by Tim Mather Entranco Inc. Detention Pond Verification Calcs. Design Volume Required for: WQCV = 0.022 ac-ft Detention Volume = 0.18 ac-ft Total Detention Volume Required = 0.202 ac-ft @ Elev. = 4975' As -Built Detention Volume For Detention Pond: Major Storm (100-year Event): Elevation (feet) Area, (ft) Areaa e (ftz) Areal (ft) Volume, (ft) Volumec„m (ft) Volumec„m (ac-ft) 69.5 1.81 0 0 70.0 1.81 18.575 35.34 9.29 9.29 0.000 70.5 35.34 133.29 231.24 66.65 75.93 0.002 71.0 231.24 338.675 446.11 169.34 245.27 0.007 71.5 446.11 544.6 643.09 272.30 517.57 0.015 72.0 643.09 752.125 861.16 376.06 893.63 0.026 72.5 861.16 960.565 1059.97 480.28 1373.92 0.040 73.0 1059.97 1170.22 1280.47 585.11 1959.03 0.057 73.5 1280.47 1464.42 1648.37 732.21 2691.24 0.078 74.0 1648.37 2087.64 2526.91 1043.82 3735.06 0.108 74.5 2526.91 3737.17 4947.43 1868.59 5603.64 0.162 75.0 4947.43 6471.39 7995.35 3235.70 8839.34 0.256 See Design Pond Volume Calculations Next Page Page 1 of 2 9/30/2002 This total pond volume exceeds design volume Design Volume Calculations For Detention Pond. Major Storm (100-year Event): Elevation Area Depth Volume CumulatiVE WQCV Volume Volume (feet) (Acres) (feet) (Ac-ft) (Ac-ft) (Ac-ft) 4969.5 0.001 0.5 0.001 0.001 4970.0 0.003 1.0 0.006 0.007 4971.0 0.010 1.0 0.014 0.021 4972.0 0.019 1 1 1 0.022 1.0 0.025 0.024 4973.0 0.030 1.0 0.037 0.061 4974.0 0.044 1.0 0.114 0.18 4975.0 0.185 0.18 1.0 0.230 0.41 4976.0 0.276 Page 2 of 2 WQCV (4972.05 ft) Less WQCV Detention Volume Required for 100-year Event (4975.0 ft) Spillway Elevation (4975.1 ft) /3 LEGEND UNE LINE ACRES Q PoNT -•-•-- STORM ----PROPERTY AREA -�---- SANITARY UNE -^-•- NEW WATER UNE EXISTING CdI ---- WATER UNE - — - NEW GAS UNE ACRES DESIGN POINT ----- CAS UNE NEW SWRARY UNE O DRY CREEK ROOOPWN CROSS SECTION UNE -- - TELEPHONE LINE -- NEW ELECTRIC UNE ' --- DRY CREEK FLOODPINN BOUNDRY UNE ELECTRIC UNE ® NEW STORM UNE r—r NEW ROOF OWVN M CREEK FLOODPWN EFE UNE �N FLOW DIRECRON SUB -BASIN FOR COUNIRY CLUB CORNERS, FOURN RUM. P.U.D. SUB -RESIN BOUNDRY RETNNNG WALL / R6 /1p /7 S 20' CONSTRUCTION \\ LANDSCAPE II --+ �"si.eZ `\n�___ _EAST_ _-___-\ \U \ ` \\ NEW DUAL 30" HDPE INST PER "COUNTRY CLUB CORNERS THIRD FILING PUD" SHEET 12 OF 42 "STORM DRAIN PLAN AND PROFlLES" X WM \ PHASE 2, DATED FEB 1, 1996 BYE \ LANDMARK ENGINEERING, LTD. STOP F______________________________i101v______- T . rw.Y�rr +lolE�� Moo _ i R ELEC. % EX 6" SAN VAULT 1 EX SAN MH __- RYDRANT 1 1 NV: 4969.1 r.^^ EX 8" SAN - EX 8" WM J ~ 4 \ 415, , v v�p ':vv7 3 / ROOF DRHLJ \ \ \ M C12THROUGH CURB; \\ I \ F�1wv1W _ \ / _ .. .♦ r.SB95f EX SAN MH ---_ EX. ELEC. RIM: 4973,96 _� --- _ VAULT INV: 4968 28 NEW REDDNING-WA4L Sly E MOUMTYN AYEMR SEE LANDSCAPE PLANS FOR red c, me. ca 80524 UM SEEDING AND MULCHING Phe:.: 270 221-5NR Fe.: 270 UI-vw REQUIREMENTS. E-men: I:de4MalNRerawr ASPHALT CURB II VAULT ,/ } PEDS POUDRE HEALTH SERVICES District Building EX 8" SAN i p 1/ ``I _ IF DRAINAGE LOT 11 PLAN \ r 1 `II• \ PARR INN Date: 10-17-01 AREA I III v — Designed: GEM Drawn: RGS — Approved: MOW p I � I Cadtl File CSDRNN.DWG w I I G z V �CONCR TE 7 ® DATE NOTES DRAWN TRICKLE PAN C12 C. 6-03-01 VET LOT 12 7-25-01 NEW RETAINING 8-10-01 \ 18"MIN. WALL C12 10-17-01 DIA. RIPRAP 11-16-01 —I EMERGENCY C1YC. PE05. \-y-SPILLWAY _ ^^^ EXIST. STRM DRAIN P BRISTLECONE DR. (60' ROW) EX'ST )iG 4' SOCA- DETENIOx1 POND SOMMA TABLE 10-YEAR STORM EVENT QSOE QPIPE QDEM4TION 1.39 Cm 0.29CF5 1.07 CPS 100-YEAR STORM EVERT QSm: QPin QDETENIION 6.00 CPS 0.33 CPS 5.67 CPS LOT 1 OF COUNTRY CLUB CORNERS FOURTH RUM P.V.D. APPROVED DNA- DRNHICE STUDY BRaME CONE SUMMARY AT 10-YEAR STORM EVEN QSTREET ORK Q10 QUflENLIDN 8.5 CPS 20.24 CPS N.87 CPS 31.13 CPS 100-YEAR STORM EVEN QSIREET QPIPE Q100 QDEIENION 23.H CPS 24.39 CPS 108.29 CPS III CM ONOTE: 1.73 Cis ALLOWABLE RELEASE RATE FROM C4 AND PORTION OF C3 AS PER APPROVED O NAGE SNDY FOR LOT 1 OF COUNTRY CLUB CORNERS FUUR H FILING P.U.D. 20 10 0 20 40 1" = 20" UTILITY PLAN APPROVAL CITY OF FORT COWNS. COLORADO APPROVED: pt) Eeynse CW CHECKED BY' Fib evd �ulmta OYetJ AY CHECRED BY' 8ta�m��b UWIt) hl. CHECKED BY PVY� mE Peme�e® M1te CHECKED BY N4 CHECKED BY' OJe DRAINAGE PLAN Scale: 1" = 20' Sheet No.: C5 of C12