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HomeMy WebLinkAboutOTTER BOX DISTRIBUTION/WAREHOUSE EXPANSION - FDP - 17-10/A - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTLARIMER COUNTY 1455000 FT OENROS- / 4932 cr � ZONE ZONE AE (EL 4924) ZONE AE . PONDEROSA OR DRIVE AE FLO? Pto?tier s l rm-- CITY OF FORT COLLINS CRY OF FORT COLLINS 080102 B"elder Creek r-25 split . LARUNER COUNTY 0 CORPORATED AREAS 080101 O 4945 4TAINED IN CI AO PALAMINI 19 e ou h moi5 EAE -JOYDANCE CT 15 I 4950 RACHEL COURT AREA UIERRY STREET iCNARGE r LARN/QR COUNTY UNNCORPORATED AREAS MIDI Legend _ 1 % annual chance (100-Year) Floodplain _ 1 % annual chance (1 00-Year) Floodway ® 0.2% annual chance (500-Year) Floodplain MAP SCALE 1"=�55000' 2® FEET METER 0 150 m PANEL 1003F FIRM F FLOOD INSURANCE RATE MAP LARIMER COUNTY, COLORADO AND INCORPORATED AREAS PANEL 1003 OF 1420 ® WE MM IME%FORFW PMEL UY DTI G9mNVdaCOMM i lY UVNBEH PdtEL wcFn ® ISED TO �" w ® FLECTLOMR ® FECTNE: February 22, 2010 ;„,.. MAP NUMBER Momoov 'ID y EFFECTME DATE DECEMBER IF, 2008 " Fltival LsvBary IN�neme�l ABwFY • ATTACHMENT 5 PORTION OF FIRM PANEL 1003 Erosion Control Cost Estimate Project Number: 236-002 Location: Fort Collins. CO Date: July 13, 2010 Total Disturbed Acres: 1.9 Estimated Unit Total EROSION CONTROL MEASURE Units Quantity Price Price Wattle Inlet Filters each 3 $100.00 $300.00 Silt Fencing L.F. 325 $1.50 $487.50 Wattle Dikes each 2 $125.00 $250.00 Vehicle Tracking Control Pads each 1 $300.00 $300.00 TOTAL = $1,337.50 AMOUNT OF SECURITY = 1.5 x $1,337.50 = TOTAL = $2,006.25 -OR- COST TO VEGETATE: TOTAL ACRES x ($1000/acre) x 1.5 = TOTAL = $2,850.00 (WHICHEVER IS GREATER) REQUIRED AMOUNT OF SECURITY = $2,850.00 0 • ATTACHMENT 4 EROSION CONTROL SURETY CALCULATION Project: 236-002 CALCULATIONS FOR RIPRAP PROTECTION AT PIPE OUTLETS Date: 7/13110 By: ATC Storm Line/Culvert Label Design Discharge (cfs) Culvert Parameters Circular Pie p (Figure MD-21) - p Rectangular Pie (Figure MD-22) Riprap Type (From Figure MD-21 or MD-22) Spec Min. Length of Riprap (ft) Y Tailwater Depth p ft ( ) Expansion Factor 1 /(2tanq) (From Figure MD-23or MD-24) Froude Parameter O/Das Max 6.0 or O/WH's Max 8.0 Urban Drainage MD pg -107 Spec Min. Width of Riprap (ft)(ft) Depth Depth of Riprap (ft) for L/2 Circular Box Culvert Dore Pipe Diameter H or H„ Culvert Height (ft) W. Culvert Width (ft) Y,/D O/D s " O!D Y,/H U5 p/yyH FM=t1N (ft) L _ i/(2tanq)' IAt/(ft) (h) Roof Drain Outfall Parking Lot Drain 4.00 2.10 0.83 1.25 0.33 0.50 0,40 0.40 5.26 1.50 6.32 1.20 N/A N/A N/A N/A 2.00 4.10 6.32 1.20 0,80 0.42 3,14 5.00 T e L Type L 4.00 5.00 4.00 5.00 1.5 1.5 • 0 ATTACHMENT 3 RIPRAP CALCULATIONS • Worksheet • Worksheet for Circular Channel Project Description Worksheet 4-INCH PVC CA Flow Element Circular Channe Method Manning's Formi Solve For Discharge Input Data Mannings Coeffic 0.013 Slope 005000 ft/ft Depth 0.33 ft Diameter 4 in Results Discharge 0.14 cfs Flow Area 0.1 ft' Wetted Perime 1.03 ft Top Width 0.02 ft Critical Depth 0.21 ft Percent Full 99.9 % Critical Slope 0.010176 ft/ft Velocity 1.56 ft/s Velocity Head 0.04 ft Specific Energ, 0.37 ft Froude Numbe 0.14 Maximum Disc 0.14 cfs Discharge Full 0.13 cfs Slope Full 0.005137 ft/ft Flow Type 3ubcritical Project Engineer: Northern Engineering Services c:\haestad\fmw\dummay.fm2 Northern Engineering Services FlowMaster v6.1 [614n] 08/10/10 03:40:13 PM O Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 PROJECT JOB FOR NORTHERN C MADE BY DATE ._SHEET BY FORT COLLINS, COLORADO 80521 Ati D�1 FIc 1 I•rL) 1 I � � I DeiFIc.e- 4- 1 Lp = C A- y! ZS7 or-1F=f a�5 Gas ------------ oo G� ­77-r4L FLOcJ oo(o 4- eoo:7- = ooZZc 6f �r t�✓C D 2,Q �i PE G . S ?o 4 G FS STAGE STORAGE TABLE ELEV AREA (sq. ft.) DEPTH (ft) AVG END INC. VOL. (cu. ft.) AVG END TOTAL VOL. (cu. ft.) CONIC INC. VOL. (cu. ft.) CONIC TOTAL VOL. (cu. ft.) 4,922.000 1.17 N/A N/A 0.00 N/A 0.00 4,922.200 64.81 0.200 6.60 6.60 4.98 4.98 4,922.400 220.36 0.200 28.52 35.11 26.98 31.96 4,922.600 398.50 0.200 61.89 97.00 61.01 92.97 4,922.800 580.20 0.200 97.87 194.87 97.30 190.27 4,923.000 766.02 0.200 134.62 329.49 134.19 324.47 4,923.200 958.23 0.200 172.43 501.92 172.07 496.53 4,923.400 1,157.13 0.200 211.54 713.45 211.22 707.76 4,923.600 1,365.75 0.200 252.29 965.74 252.00 959.76 4,923.800 1,584.04 0.200 294.98 1260.72 294.71 1254.46 4,924.000 1,813.30 0.200 339.73 1600.45 339.48 1593.94 0 • 7 I+20 Gv, FT- klSf-L "-m23.jo 0 LJ WATER QUALITY POND DESIGN CALCULATIONS Southeast Water Quality Pond - POND B Project: 236-002 By: ATC Date: 8.10.10 REQUIRED STORAGE & OUTLET WORKS: BASIN AREA = 0.830 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS PERCENT = 89.00 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS RATIO = 0.8900 <— CALCULATED WQCV (watershed inches) = 0.393 <-- CALCULATED from Figure EDB-2 WQCV (ac-ft) = 0.033 <-- CALCULATED from UDFCD DCM V.3 Section 6.5 WQ Depth (ft) = 2.000 <-- INPUT from stage -storage table AREA REQUIRED PER ROW, a (in2) = 0.083 <— CALCULATED from Figure ED13-3 CIRCULAR PERFORATION SIZING: dia (in) = 3/8 <-- INPUT from Figure 5 n = 1 <-- INPUT from Figure 5 t (in) = 1 /4 <-- INPUT from Figure 5 number of rows = 6 <-- CALCULATED from WQ Depth and row spacing STAGE STORAGE TABLE ELEV AREA (sq. ft.) DEPT H (ft) AVG END INC. VOL. (cu. ft.) AVG END TOTAL VOL. (cu. ft.) CONIC INC. VOL. (cu. ft.) CONIC TOTAL VOL. (cu. ft.) 4,920.600 12.62 N/A N/A 0.00 N/A 0.00 4,920.800 67.22 0.200 7.98 7.98 7.26 7.26 4,921.000 137.79 0.200 20.50 28.48 20.08 27.35 4,921.200 212.14 0.200 34.99 63.48 34.73 62.07 4,921.400 292.44 0.200 50.46 113.94 50.24 112.32 4,921.600 386.01 0.200 67.84 181.78 67.63 179.95 4,921.800 496.03 0.200 88.20 269.98 87.97 267.92 4,922.000 624.99 0.200 112.10 382.09 111.85 379.77 4,922.200 765.98 0.200 139.10 521.18 138.86 518.63 4,922.400 914.09 0.200 168.01 689.19 167.79 686.42 4,922.600 1,067.86 0.200 198.19 887.39 198.00 884.42 4,922.800 1,244.75 0.200 231.26 1118.65 231.03 1115.45 4,923.000 1,422.22 0.200 266.70 1385.34 266.50 1381.95 4,923.200 1,610.36 0.200 303.26 1688.60 303.06 1685.02 4,923.400 1,810.29 0.200 342.06 2030.67 341.87 2026.89 4,923.600 2,023.08 0.200 383.34 2414.00 383.14 2410.03 4,923.800 2,251.28 0.200 427.44 2841.44 427.23 2837.26 4,924.000 2,582.32 0.200 483.36 3324.80 482.98 3320.24 • VOL . 1-4-}Z Gv.tT • u WATER QUALITY POND DESIGN CALCULATIONS Southwest Water Quality Pond - POND A Project: 236-002 By: ATC Date: 8.10.10 REQUIRED STORAGE & OUTLET WORKS: BASIN AREA = 0.910 <--INPUT from impervious calcs BASIN IMPERVIOUSNESS PERCENT = 95.00 <— INPUT from impervious calcs BASIN IMPERVIOUSNESS RATIO = 0.9500 <--CALCULATED WQCV (watershed inches) = 0.447 <-- CALCULATED from Figure ED13-2 WQCV (ac-ft) = 0.041 <--CALCULATED from UDFCD DCM V.3 Section 6.5 WO Depth (ft) = 2.500 <-- INPUT from stage -storage table AREA REQUIRED PER ROW, a (in) = 0.077 <— CALCULATED from Figure EDB-3 CIRCULAR PERFORATION dia (in) = 5/16 <--INPUT from Figure 5 n = 1 <-- INPUT from Figure 5 t (in) = 1 /4 <— INPUT from Figure 5 number of rows = 4 <— CALCULATED from WQ Depth and row spacing 171 ATTACHMENT 2 WATER QUALITY POND CALCULATIONS DEVELOPED CONDITIONS RUNOFF COMPUTATIONS Project: 236-002 Date: 8.10.10 By: ATC Design Point Basins Area, A acres 2-yr Tc min 100-yr Tc min C2 C100 Intensity, 12 in/hr Intensity, 1100 in/hr) Flow, Q2 (cfs) Flow, Q100 (cfs 1 1 0.21 5.0 5.0 0.95 1.00 2.85 9.95 0.6 2.1 2 2 0.14 5.5 5.1 0.25 0.31 2.85 9.95 0.1 0.4 3 3 0.56 5.0 5.0 0.95 1.00 2.85 9.95 1.5 5.6 4 4 0.83 5.0 5.0 0.92 1.00 2.85 9.95 2.2 8.3 W • DEVELOPED CONDITIONS 100-YR TIME OF CONCENTRATION COMPUTATIONS Fort Collins, Colorado Overland Flow, Time of Concentration: T _ 1.87(1.1—C*Cf — Sy Gutter/Swale Flow. Time of Concentration: Tt=L/60V T, = Ti + Tt (Equation RO-2) Intensity, 1 From Figures 3.3.1-2 (Area II) Velocity (Gutter Flow), V = 20•S (Equation PO-4) Velocity (Swale Flow), V = 15•S Rational Equation: Q = CiA (Equation RO-1) Project: 236-002 Date: 8.10.10 By: ATC Overland Flow Gutter Flow Swale Flow Time of Concentration Design Point Basins C*Cf Length, L ft Slope, S % Ti min Slope, S % Velocity, V ft/s T, min Length, L ft Slope, S % Velocity, V ft/s Tt min 100-YR T. min 1 1 1.00 40 2.0 0.9 E60 0.6 1.55 0.6 0 0.0 0.00 N/A 5.0 2 2 0.31 30 4.0 5.10.0 0.00 N/A 0 0.0 0.00 N/A 5.1 3 3 1.00 156 0.5 2.90.0 0.00 N/A 0 0.0 0.00 N/A 5.0 4 4 1.00 150 0.5 2.8 0 1 0.0 0.00 N/A 0 0.0 0.00 N/A 5.0 a • DEVELOPED CONDITIONS 2-YR TIME OF CONCENTRATION COMPUTATIONS Fort Collins. Colorado Overland Flow, Time of Concentration: T - 1.87(1.1 - C * Cf)-JL S' X Gutter/Swale Flow, Time of Concentration: Tt=L/60V TC = T; + Tt (Equation RO-2) Intensity, I From Figures 3.3.1-2 (Area II) Velocity (Gutter Flow), V = 20•S (Equation RO-4) Velocity (Swale Flow), V = 15•S i Rational Equation: Q = CiA (Equation RO-1) Project: 236-002 Date: 8.10.10 By: ATC Overland Flow Gutter Flow Swale Flow Time of Concentration Design Point Basins C•Cf Length, L (ft) Slope, S N T, (min) Length, L (ft) Slope, S N Velocity, V (ft/s) T, (min) Length, L (ft) Slope, S N Velocity, V (ft/s) Tt (min) 2-YR T. (min) 1 1 0.95 40 2.0 1.4 60 0.6 1.55 0.6 0 0.0 0.00 N/A 5.0 2 2 0.25 30 4.0 5.5 0 0.0 0.00 N/A 0 0.0 0.00 N/A 5.5 3 3 0.95 156 0.5 4.3 0 0.0 0.00 N/A 0 0.0 0.00 N/A 5.0 4 4 0.92 1 150 0.5 1 5.1 0 1 0.0 0.00 1 N/A 0 0.0 0.00 N/A 5.0 DEVELOPED COND. COMPOSITE % IMPERVIOUSNESS AND RUNOFF COEFFICIENT CALCULATIONS Character of Surface Streets, Parking Lots, RoofS, Alleys, and Drives: Asphalt................................................................................. Concrete.............................................................................. Gravel.................................................................................. Roofs.................................................................................. Lawns and Landscaping SandySoil............................................................................ Clayey Soil............................................................................ Runoff Coefficient Percentage Imperviousness Project: 236-002 Date: 8.10.10 By: ATC 2-year c, = 1.00 100-year C, = 1.25 0.95 100 0.95 90 0.50 40 0.95 90 0.15 0 0.25 0 Runoff Coefficients are taken from the City of Fort Collins Storm Drainage Design Criteria and Construction Standards, Table 3-3 Basin ID Basin Area (s.f.) Basin Area (acres) Area of Asphalt Streets, Parking Lots, and Alleys (sf) Area of Roofs, Walks, and Driveways (sf) Area of Gravel Parking and Drives (sf) Area of Lawn and Landscape (sf) 2-year Composite Runoff Coefficient 100-year Composite Runoff Coefficient Composite % Impervious 1 9002 0.21 9002 0 0 0 0.95 1.00 100.00 2 6096 0.14 0 0 0 6096 0.25 0.31 0.00 3 1 24481 0.56 0 24481 0 0 0.95 1.00 90.00 4 36137 0.83 9300 25265 0 1572 0.92 1.00 88.66 •,--• ••,•,,,,,,,,,.,tea ••IIQ\IIOI GJVII0 L UI a UIMULV, 1 IUVU U=11 YIUUPUU LUYUL11U1 M LHU rwpndn column • 0 CJ 9 ATTACHMENT 1 DEVELOPED DRAINAGE CALCULATIONS 0 0 The base (100-year) flood elevation in the vicinity of the proposed structure is 4925.00 which is referenced to the City of Fort Collins NGVD 29. The finished floor of the proposed structure is at elevation 4929.42, allowing the regulatory flood protection elevation (minimum 2-feet above base flood elevation) to be met. All HVAC will also exceed the regulatory flood protection elevation. The proposed structure is located outside of the 100-year floodplain boundary. Proposed use of the structure is a warehouse facility. The structure's foundation will be of slab on grade construction; the outer wall of the structure will be supported by a spread footing. The regulatory half -foot floodway also encroaches the site and is delineated on the Drainage Exhibit. No fill is proposed within the half -foot floodway. A floodplain use permit will be required for each structure and each site construction element (water quality pond, bike path, parking lots, utilities, etc.) in the floodplain. Additionally, FEMA elevation certificates must be completed and approved for any structures in the floodplain prior to issuance of Certificate of Occupancy. The development will be in compliance with all applicable floodplain regulations per Chapter 10 of City Code. Please see attachments 1 through 4 for all pertinent drainage calculations for the proposed construction: Attachment 1 - Developed drainage calculations Attachment 2 - Water quality pond calculations Attachment 3 - Riprap calculations Attachment 4 - Erosion control surety deposit calculations Attachment 5 — Portion of FIRM panel 1003 If you should have any questions as you review this report, please feel free to contact us. HIRING SERVICES, INC. aron Cv r, PE UM!2" 1O: n� NORTHERN ADDRESS: PHONE: 970.221.4158 wEOSITE. 200 S. College Ave. Suite 100 E N G I N E E R I N G Fort Collins, C080524 FAX:970.221.4159 www.northernengineering.com August 27, 2010 City of Fort Collins Stormwater Utility 700 Wood Street Fort Collins, Colorado 80521 RE: Addendum to Final Drainage Report — Interchange Business Park Otterbox Warehouse Expansion Dear Staff: Northern Engineering is pleased to submit this Addendum to the Final Drainage Report for Interchange Business Park dated April 13, 2001. The Otterbox Warehouse Expansion will occur within Lots 10 and 11 of Interchange Business Park. The expansion will consist of the addition of warehouse space to the current Otterbox facility located within Lots 9 and 10 of Interchange Business Park. In addition to construction of the warehouse addition, associated parking space and utilities will be constructed with the expansion. Also, expansion/modification to the existing water quality pond, at the rear of the building, will be constructed. A new water quality pond will be constructed at the northwest corner of the property as well. The expanded/modified pond at the rear of the building will consist of the addition of volume by grading. Also a modified outlet structure, consisting of the addition of a standpipe with water quality holes, will be constructed. The new water quality pond at the northwest corner of the property will be constructed as a standard 40-hour extended detention basin. In conformance with the approved report for Interchange Business Park, water quality enhancement is required. However,'detention is not required with the Interchange Business Park development, due to its proximity to the Boxelder Creek major drainageway. The Boxelder Creek 100-year floodplain encroaches the project site and is delineated on the Drainage Exhibit (see back map pocket). FEMA FIRM Panel Number 1003 for Larimer County (LOMR dated 2/22/2010) is referenced in this study, and delineation of floodplain and floodway boundaries shown on the Drainage Exhibit are consistent with the FIRM.