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HomeMy WebLinkAboutDrainage Reports - 02/11/1998ebted THE SEAR -BROWN GROUP `1 �a FULL -SERVICE DESIGN PROFESSIONALS FORMERLY RBD, INC. 209 SOUTH MELDRUM FORT COLLINS, COLORADO 80521-2603 970-482-5922 FAX:970-482-6368 L1 rR LE o IE MAR 21998 February 11, 1998 1` Mr. Basil Hamden City of Fort Collins Utility Services Stormwater 235 Mathews Fort Collins, Colorado 80522 Subject: Addendum to the Final Drainage and Erosion Control Study for the Oakridge Business Park Seventeenth Filing Dear Basil: We are submitting to you, for your review and approval, this addendum to the Final Drainage and Erosion Control Study for the Oakridge Business Park Seventeenth Filing. All computations and figures within this report are in compliance with the City of Fort Collins Storm Drainage Design Criteria. This addendum pertains to the southeast section of the original site. The building pad has been expanded but it still fits the features of the site and falls within the easements. Sidewalks are proposed for the north and east side of the building and curb and gutter will be located around the perimeter of the site. In order to maximize the back lot area on the east.side of the .building, the two existing 247 storm sewer pipes will be extended to the north and south. The curb and gutter along the east side of the back lot is located approximately above the culverts allowing for a maximum of 3:1 slope down to the railroad easement. In the vicinity of the electrical pole, the curb and gutter will run along the railroad easement in order to meet the electric company's requirement of a 25-foot radius of clearance. The historic drainage patterns of flow from west to•east have remained. Generally, the 10 and 100 year. developed flows will be routed through the parking lots and along the curb and gutter into the open channel that runs along the south and east side of the building. This channel outlets into the existing regional detention pond which was previously designed to accommodate the runoff from this site. NEW YORK•PENNSYLVAN]A COLORADO•UTAH STANDARDS IN EXCELLENCE EQUAL OPPORTUNITY EMPLOYER 1r, SEAR -BROWN Specifically, the back lot flows have been directed southeast through the lot and along the curb and gutter to the outlet into the open channel. The flows to the north side of the building will be directed to the culvert on the east side of the site. There will be riprap at the inlet and outlet of the culvert for erosion control. (See attached riprap and HY8 calculations) The flows to the west side of the building will be directed to the south into the open channel. We appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. Respectfully, The Sear -Brown Group Engineering Consultants zze';'e' aL - fro m Allen-Morely ject Manager CURRENT DATE: 02-11-1998 CURRENT TIME: 11:31:54 FHWA CULVERT ANALYSIS HY-8, VERSION 6.0 1 FILE DATE: 02-11-1998 FILE NAME: MERIT C SITE DATA CULVERT SHAPE, MATERIAL, INLET U L INLET OUTLET CULVERT BARRELS V ELEV. ELEV. LENGTH SHAPE SPAN RISE MANNING INLET NO. (ft) (ft) (ft) MATERIAL (ft) (ft) n TYPE 1 60.39 59.83 159.58 2 RCP 2.00 2.00 .013 CONVENTIONAL 2 3 4 5 6 SUMMARY OF CULVERT FLOWS (cfs) FILE: MERIT DATE: 02-11-1998 ELEV (ft) TOTAL 1 2 3 4 5 6 ROADWAY ITR 0.00 20.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 62.44 23.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 62.59 26.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 62.98 29.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 63.23 32.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 63.11 35.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 63.24 38.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 63.41 41.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 63.47 41.8 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 63.93 47.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 64.22 50.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0 0.00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 OVERTOPPING SUMMARY OF ITERATIVE SOLUTION ERRORS FILE: MERIT DATE: 02-11-1998 HEAD HEAD TOTAL FLOW % FLOW ELEV (ft) ERROR (ft) FLOW (cfs) ERROR (cfs) ERROR 0.00 0.000 20.00 0.00 0.00 62.44 0.000 23.00 0.00 0.00 62.59 0.000 26.00 0.00 0.00 62.98 0.000 29.00 0.00 0.00 63.23 0.000 32.00 0.00 0.00 63.11 0.000 35.00 0.00 0.00 63.24 0.000 38.00 0.00 0.00 63.41 0.000 41.00 0.00 0.00 63.47 0.000 41.77 0.00 0.00 63.93 0.000 47.00 0.00 0.00 64.22 0.000 50.00 0.00 0.00 <1> TOLERANCE (ft) = 0.010 <2> TOLERANCE (Y,) = 1.000 CURRENT DATE: 02-11-1998 FILE DATE: 02-11-1998 CURRENT TIME: 11:31:54 FILE NAME: MERIT PERFORMANCE CURVE FOR CULVERT 1 - 2( 2.00 (ft) BY 2.00 (ft)) RCP DIS- HEAD- INLET OUTLET CHARGE WATER CONTROL CONTROL FLOW NORMAL CRIT. OUTLET TW OUTLET TW FLOW ELEV. DEPTH DEPTH TYPE DEPTH DEPTH DEPTH DEPTH VEL. VEL. (cfs) (ft) (ft) (ft) <F4> (ft) (ft) (ft) (ft) (fps) (fps) 20.00 62.21 1.70 1.82 3-M1t 1.29 1.13 1.65 1.65 3.61 1.59 23.00 62.44 1.86 2.05 3-M1t 1.43 1.22 1.75 1.75 3.95 1.64 26.00 62.59 2.03 2.20 3-M1t 1.59 1.29 1.84 1.84 4.29 1.69 29.00 62.98 2.20 2.59 3-M2t 2.00 1.37 1.92 1.92 4.71 1.74 32.00 63.23 2.38 2.84 3-M2t 2.00 1.44 2.00 2.00 5.10 1.78 35.00 63.11 2.57 2.72 3-M1f 2.00 1.50 2.00 2.07 5.57 1.82 38.00 63.24 2.79 2.85 3-M1f 2.00 1.56 2.00 2.14 6.05 1.86 41.00 63.41 3.02 2.99 3-M1f 2.00 1.62 2.00 2.20 6.53 1.90 41.77 63.47 3.08 3.03 3-M1f 2.00 1.63 2.00 2.22 6.65 A 1.91 5Y1 >41 }3 aA E1K,r QxweQ OF 47.00 63.93 3.54 3.30 3-M1f 2.00 1.71 2.00 2.32 7.48 1.96 50.00 64.22 3.83 3.47 3-MIf 2.00 1.75 2.00 2.38 7.96 1.99 El. inlet face invert 60.39 ft El. outlet invert 59.83 ft El. inlet throat invert 0.00 ft El. inlet crest 0.00 ft ***** SITE DATA ***** CULVERT INVERT ************** INLET STATION 159.58 ft INLET ELEVATION 60.39 ft OUTLET STATION 0.00 ft OUTLET ELEVATION 59.83 ft NUMBER OF BARRELS 2 SLOPE (V/H) 0.0035 CULVERT LENGTH ALONG SLOPE 159.58 ft ***** CULVERT DATA SUMMARY ************************ BARREL SHAPE CIRCULAR BARREL DIAMETER 2.00 ft BARREL MATERIAL CONCRETE BARREL MANNING'S n 0.013 INLET TYPE CONVENTIONAL INLET EDGE AND WALL SQUARE EDGE WITH HEADWALL INLET DEPRESSION NONE CURRENT DATE: 02-11-1998 CURRENT TIME: 11:31:54 TAILWATER ******* REGULAR CHANNEL CROSS SECTION **************** 3 FILE DATE: 02-11-1998 FILE NAME: MERIT BOTTOM WIDTH 1.00 ft SIDE SLOPE H/V (X:1) 4.0 CHANNEL SLOPE V/H (ft/ft) 0.005 MANNING'S n (.01-0.1) 0.060 CHANNEL INVERT ELEVATION 59.83 ft CULVERT NO.1 OUTLET INVERT ELEVATION 59.83 ft ******* UNIFORM FLOW RATING CURVE FOR DOWNSTREAM CHANNEL FLOW W.S.E. FROUDE DEPTH VEL. SHEAR (cfs) (ft) NUMBER (ft) (f/s) (psf) 20.00 61.49 0.217 1.65 1.59 0.52 23.00 61.58 0.219 1.75 1.64 0.55 26.00 61.67 0.220 1.84 1.69 0.57 29.00 61.75 0.221 1.92 1.74 0.60 32.00 61.83 0.222 2.00 1.78 0.62 35.00 61.90 0.223 2.07 1.82 0.65 38.00 61.97 0.224 2.14 1.86 0.67 41.00 62.03 0.225 2.20 1.90 0.69 41.77 62.05 0.226 2.22 1.91 0.69 47.00 62.15 0.227 2.32 1.96 0.73 50.00 62.21 0.228 2.38 1.99 0.74 ROADWAY OVERTOPPING DATA ROADWAY SURFACE PAVED EMBANKMENT TOP WIDTH 0.00 ft CREST LENGTH 130.00 ft OVERTOPPING CREST ELEVATION 63.00 ft SEcrioo F DRAINAGE DITCH WORKSHEET Worksheet for Trapezoidal Channel 14tOO =10. 01;) Project Description Project File untitled.fm2 Worksheet DRAINAGE DITCH Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.060 Channel Slope 0.005000 ft/ft Left Side Slope 4.000000 H : V Right Side Slope 3.000000 H : V Bottom Width 1.00 ft Discharge 13.39 cfs Results Depth 1.47 ft Flow Area 9.08 ftZ Wetted Perimeter 11.74 ft Top Width 11.32 ft Critical Depth 0.85 ft Critical Slope 0.069821 ft/ft Velocity 1.48 ft/s Velocity Head 0.03 ft Specific Energy 1.51 ft Froude Number 0.29 Flow is subcritical. D15c"atc _ 100) = I&39 LF 5 02/12/98 FlowMaster v5.15 12:04:29 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Cross Section-F Cross Section for Trapezoidal Channel Project Description Project File untitled.fm2 Worksheet DRAINAGE DITCH Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Section Data Mannings Coefficient 0.060 Channel Slope 0.005000 ft/ft Depth. 1.47 ft Left Side Slope 4.000000 H : V Right Side Slope 3.000000 H: V Bottom Width 1.00 ft Discharge 13.39 cfs 1.00 ft 1.47 ft 1 vL�, H 1 NTS 02/12/98 12:04:34 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 FlowMaster v5.15 Page 1 of 1 DRAINAGE DITCH WORKSHEET Worksheet for Trapezoidal Channel 010 % 425 cFs Project Description Project File untitled.fm2 Worksheet DRAINAGE DITCH Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.060 Channel Slope 0.005000 ft/ft Left Side Slope 4.000000 H : V Right Side Slope 3.000000 H : V Bottom Width 1.00 ft Discharge 5.65 cfs Results Depth 1.03 ft Flow Area 4.76 ft2 Wetted Perimeter 8.52 ft Top Width 8.22 ft Critical Depth 0.57 ft Critical Slope 0.078310 ft/ft Velocity 1.19 ft/s Velocity Head 0.02 ft Specific Energy 1.05 ft Froude Number 0.28 Flow is subcritical. Olx►w4"=(1-33XQID)' 6.65 02/12/98 FlowMaster v5.15 12:04:58 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Cross Section - F Cross Section for Trapezoidal Channel Project Description Project File untitled.fm2 Worksheet DRAINAGE DITCH Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Section Data Mannings Coefficient 0.060 Channel Slope 0.005000 ft/ft Depth 1.03 ft Left Side Slope 4.000000 H : V Right Side Slope 3.000000 H: V Bottom Width 1.00 ft Discharge 5.65 cfs 1.00 ft 1.03 ft VD H 1 NTS 02/12/98 12:05:07 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 FlowMaster v5.15 Page 1 of 1 The Sear -Brown Group Riprap Design Project: Merit building Designer: J Allen-M Project #: 807-001 Date: 02/11 /98 Location: south outfall Pipe dia.: 24 in Discharge 20.89 cfs 1. Required riprap type Tailwater: 2.2 ft Max. V: 5 ft/s Q/D^2.5 = 3.69 < 6 --> use design charts D = 2.00 ft Yt/D = 1.10 Q/DA1.5 = 7.39 d50 = in ----> Use Class 6 riprap 2. Expansion factor. 1 / [2 tan(theta)] = 4.4 3. Riprap length: At=QN= L = 1/[2tan(theta)]'(At/Yt - D) _ 4. Governing limits: L>3D= 6 ft L<10D= 20 ft 5. Maximum depth: Depth = 2d50 = 2 (0 in / 12) _ 4.178 ft2 ft increase length to 6 ft _> Oft --> OK 1ft 6. Bedding: Use 1 ft thick layer of Type II (CDOT Class A) bedding material. 7. Riprap width: Width = 3D = 3 (24 in /12) _ Summary Class 6 riprap Length = 6 ft Depth = 1 ft Width = 6 ft C:1fii Use Class 6 Riprap as minimu 11-Feb-98