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HomeMy WebLinkAboutDrainage Reports - 10/11/2000PROPERTY OF FORT COLLINS LT' nXrIES Fna! A proud. Report �• Da`. 10 DRAINAGE AND EROSION CONTROL CALCULATIONS TIMBERLINE ROAD / DRAKE ROAD IMPROVEMENTS J R ENGINEERING DRAINAGE AND EROSION CONTROL CALCULATIONS TIMBERLINE ROAD / DRAKE ROAD IMPROVEMENTS Prepared for: Rigden Farm, LLC and the City of Fort Collins Prepared by: JR Engineering 2620 East Prospect Road, Suite 190 Fort Collins, Colorado 80525 (970)491-9888 July 22, 1999 Revised March 23, 2000 Revised June 26, 2000 Revised August 31, 2000 Job Number 9164.03 I 11 1 1 1 1 1 1 August 31, 2000 Basil Hamdan City of Fort Collins Stormwater Utility P.O. Box 580 Fort Collins, CO 80522-0580 Re: Timberline Road/Drake Road Improvements — Drainage and Erosion Control Dear Basil, We are pleased to resubmit for your review, this Drainage and Erosion Control Plan and associated calculations for the Timberline Road and Drake Road Improvement Plan. All calculations have been completed in compliance with the City of Fort Collins Storm Drainage Design Criteria. Project Description The Timberline Road and Drake Road Improvements Plan is a joint project between Rigden Farm, LLC and the City of Fort Collins. The project includes the construction of Timberline Road to interim conditions (ie. a four -lane major arterial) between Vermont Drive and up to and including the intersection of Timberline Road and Drake Road. Drake Road shall be constructed to the ultimate arterial design between the Timberline Road/Drake Road intersection and the existing railroad tracks to the west. Timberline Road to the north and Drake Road to the east shall be transitioned from the new intersection design back to their existing configuration. The existing curb and gutter along the west side of Timberline Road and the south -side of Drake Road shall remain in place with this project. Portions of the roadway improvements will be constructed without curb and gutter at this time. This includes Timberline Road north of the intersection, the north side of Drake Road on both sides of the intersection, and the easterly portion of the south side of Drake Road east of the intersection. Runoff from these areas will sheet flow off the roadway as it has historically. Proposed Drainage Patterns Runoff from Timberline Road and Drake Road will generally follow existing flow patterns at close to historic rates. The enclosed Drainage Exhibit shows locations of proposed subbasins, which are described in the following paragraphs. Subbasins A, B and C were hydrologically analyzed using the Rational Method in order to size proposed drainage facilities. Subbasins D and E were not hydrologically evaluated since they are included in drainage reports and calculations for adjacent projects. ' Drainage Report Timberline Road/Drake Road Improvements Page 2 of 3 Timberline Road south of the Drake Road intersection is currently cross -sloped (ie. no ' centerline crown) and drains west to the Meadows East Pond via a series of storm drainage facilities. Runoff along the south side of Drake Road to the west of the Timberline Road/Drake Road intersection is also directed to the Meadows East Pond. The proposed ' widening of Timberline Road and Drake Road shall not increase the runoff to the Meadows East Pond; therefore, a detailed analysis of the existing drainage facilities to the west was not warranted. Runoff from the north side of Drake Road east of the intersection and the east side of Timberline Road north of the intersection will sheet flow off of the roadway as it has done ' historically. The existing private irrigation ditch that runs parallel and east of Timberline Road north of Drake Road will be relocated to the east. ' Subbasin A includes the area north of the Custer Drive entrance and south of Drake Road. Runoff will be directed to the proposed low point at flowline station 30+12.71. At this low point there is a proposed five-foot wide curb opening and sidewalk culvert which will direct ' runoff into an open channel that discharges into Rigden Farm Detention Pond 212. The receiving channel and storm drainage. easement have been provided as part of Rigden Farm ' Filing One. The curb opening and sidewalk culvert were designed to convey the peak 10-year runoff from Basin A. In the event of a 100-year storm, flow will overtop the sidewalk and will still be directed to the receiving channel. In the future when ultimate development ' Rigden Farm is complete, a storm sewer system may be needed to convey runoff from Timberline Road to Pond 212. A preliminary evaluation of a future system was completed and is included with this letter report. ' Subbasin B includes the area tributary to the approximately 530-feet of proposed curb and gutter along the south side of Drake Road immediately east of Timberline Road. Runoff from this area will discharge to an existing borrow ditch of adequate capacity and flow east. Riprap will be provided at the point where the curb and gutter ends. These flows will continue to the east eventually to the Fossil Creek Reservoir Inlet Ditch as they have historically. In the ' future these flows will be detained in detention facilities for Rigden Farm. Subbasin C includes the west side of Timberline Road north of the intersection and the north ' side of Drake Road west of the intersection. With this proposal runoff from this basin will sheet flow off of the roadway and into a roadside ditch that drains to a low point at design point C. A 24" RCP that connects to the North Tributary Storm Sewer is being installed with ' the Timberline Road improvements to avoid future pavement removal. This 24" RCP stub is being provided for connection to a future detention/storm sewer system for the basin northwest of the Timberline Road/Drake Road intersection. Runoff from the streets will be ' required to enter this future detention pond before entering the North Tributary Storm Sewer system to attenuate the flow and provide water quality. ' Subbasin D includes the east side of Timberline Road between the proposed Timberline Church northernmost entrance and Custer Drive. Runoff from this area will flow north to Custer Drive and then east on Custer Drive. The PDP drainage report for Rigden Farm ' Drainage Report Timberline Road/Drake Road Improvements Page 3 of 3 ' accounts for this runoff and directs it down Custer drive, into the storm sewer system under Custer Drive and into a water quality pond adjacent to the Foothills Basin Regional Channel. Subbasin E extends from the Timberline Church's northernmost entrance to the high point in Timberline Road at station 11+23.04. Runoff from this area flows north and will turn east into the Timberline Church site. The current plans for the Timberline Church show this storm runoff being directed through the Timberline Church site and into the detention and water quality pond on the Timberline Church site. From the detention and water quality pond on the Timberline Church site the runoff is released into the Foothills Basin Regional Channel. Erosion Control ' Erosion and sedimentation will be controlled during construction with silt fences, straw bale barriers, seeding and mulching. Silt fencing and straw bales barriers will be placed as ' necessary in the construction area, and will be maintained by the contractor. The contractor shall carry out proper measures as necessary to reduce dust nuisance, and to prevent dust nuisance that has originated from his operations from damaging crops, orchards, cultivated ' fields, and dwellings, or causing nuisance to persons. Soils exposed during land disturbing activity (stripping, grading, utility installations, stockpiling, filling, etc.) will be kept in a roughened condition by ripping or disking along land contours until mulch, vegetation or ' other permanent erosion control is installed. No soils in areas outside the project street rights of way shall remain exposed by land disturbing activity for more than thirty (30) days before required temporary or permanent erosion control (e.g. seed/ mulch, landscaping, etc.) is ' installed, unless otherwise approved by the Stormwater Utility. Vegetation will not be considered established until a ground cover is achieved which is demonstrated to be mature and stable enough to control soil erosion as specified in paragraph 11.3.10 of the City of Fort ' Collins Storm Drainage Construction Standards. An erosion control cost estimate and effectiveness calculations are included with this report. ' Permanent erosion control measures include the use of riprap at locations where stormwater runoff becomes concentrated and is warranted by the flow conditions. Riprap sizing calculations are included with this report. ' Conclusion ' The drainage plan presented herein is in compliance with the City of Fort Collins Storm Drainage Design Criteria. We appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. ' Sincerely, C33441 Robert Almirall, P.E. Project Manager Attachments JR Engineering 2620 E. Prospect Rd., Ste. 190, Fort Collins, CO 8525 RUNOFF COEFFICIENTS & % IMPERVIOUS LOCATION: TIMBERLINE & DRAKE PROJECT NO: 9164.03 COMPUTATIONS BY: J. ZUNG SUBMITTED BY: JR ENGINEERING DATE: 3/21/00 Recommended Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria Recommended % Impervious from Urban Storm Drainage Criteria Manual - Calculated C coefficients are area weighted Streets, parking lots (asphalt) Lawns (flat <2%, sandy soil) General multi -family area General Single-family area General commercial area Runoff % coefficient Impervious C 0.95 100 0.10 0 0.65 70 0.65 55 0.85 90 SUBBASIN DESIGNATION TOTAL AREA (ac.) TOTAL AREA (sQ ft) MULTI -FAMILY AREA (soft) COMMERCIAL AREA (sq.ft) SINGLE-FAMILY AREA (sq.ft) PAVED AREA (sq.ft) LANDSCAPE AREA (sq.ft) RUNOFF COEFF. (C) A 2.20 95,978 0 0 0 78,993 16,985 0.80 B 0.70 30,344 1 0 0 0 1 25,244 5,100 0.81 C 4.37 190,393 0 0 0 190,393 0 1 0.95 D 0.95 41,382 E 2.15 93,654 x:t916403-Rigden FannlacadlTimberilne DrakeWrainageUimberflowAs I .1 } ' O Z 0 y Z W O Z 00 ' V 0 LL a 0 u) W H 1 1 S A A � � O W W e= C W e � P _oN N W rn 0� U p 0 F )0.0 0 0 Y Q W C r m n J Z � G Oi tC E LL 4 M M O � E a o .. Y y o o m U 7 r m w U � 3 LL� •E � n ld e J W Z a> M m Q > m U m m m m C p r c m c c o 0 0 R c e o 0 0 H V V m 0 0 r= m o 0 J c° Q> J K Cl N O E 0 0 0 d fV fV N O o N O O N z ZQ c m m a � J v O H W O o 0 y v N fV O V z mQ m U m U) m z z 7 Q y a Q m U w y O � (0 7 c l0 c rn y G_ O U r LL O U O Cl) M N O] lLL O w c IZ N 3 11 1 N Zr 3 c7i c LL co 7 O rr w E N ,Y - Cl N O C 7 cp C V E n E o a to N 11 U Co O O a C e > �7 E c l6 m + J O U E Cl) E Z c p E ro ; n Q ._ D 0 w N X E JR Engineering 2620 E. Prospect Rd., Ste. 190. Fort Collins. CO 80525 RATIONAL METHOD PEAK RUNOFF Minor Storm for Commercial Areas (10-YEAR) LOCATION: TIMBERLINE & DRAKE PROJECT NO: 9164.03 COMPUTATIONS BY: J. ZUNG SUBMITTED BY: JR ENGINEERING DATE: 3/21/00 10 yr storm, CIF = 1.00 DIRECT RUNOFF CARRY OVER TOTAL REMARKS Design Point Tributary Sub -basin A (ac) C Cf tc (min) i (in/hr) Q (10) Ids) from Design Point Q (10) (ds) 0(10)tot (ds) A A 220 0.80 10.7 3.70 6.52 6.52 B B 0.70 0.81 9.9 3.81 2.14 2.14 C C 4.37 0.95 16.3 3.06 12.70 12.70 Q=CrCiA limberflow.xls Q = peak discharge (cfs) C = runoff coefficient Cf = frequency adjustment factor i = rainfall intensity (in/hr) from City of Fort Collins IDF curve (4/16/99) A = drainage area (acres) i = 41.44 / It0+tc)o' 7' I I I I I q I I � k 2k 0Z no k§ 2 w k LO - §\_ . /})C4 U) \im §/§r 2 [ LIJ y \ a.0 ) � ,�, z� \\ �§ § z {/2 aww !/E 2;; 00 ) | I JR Engineering 2620 E. Prospect Rd.. Ste. 190, Fort Collins, CO 80525 t 1 1 1 1 1 RATIONAL METHOD PEAK RUNOFF (100-YEAR) LOCATION: TIMBERLINE & DRAKE PROJECT NO: 9164.03 COMPUTATIONS BY: J. ZING SUBMITTED BY: JR ENGINEERING DATE: 3/2I/00 100 yr storm, Cf = 1.25 DIRECT RUNOFF CARRY OVER TOTAL REMARKS Des. Point Area Design. A (ac) C Cf tc (min) i (inrhr) Q (100) Ws) from Design Point Q (100) Ws) Q(100)tot (CIS) A A 220 1.00 8.5 8.28 18.23 18.2 B B 0.70 1.00 7.8 8.52 5.94 5.9 C C 4.37 1.00 15.8 6.34 27.71 27.7 Q=CiA Q = peak discharge (CIS) C = runoff coefficient i = rainfall intensity (in/hr) from City of Fort Collins IDF curve (4/16199) A = drainage area (acres) i = 84.682 / (10+ tcf°' 8mber0owAs ' OesI5n I?aigi IN ' Timberline Rd Curb Cut - 10-yr Storm Worksheet for Rectangular Channel Project Description Project File x:\916403 - rigden farm\drainage\projectl.fm2 ' Worksheet Flow Element Timberline curb cut Rectangular Channel Method Manning's Formula For Channel Depth tSolve Input Data Mannings Coefficient 0.012 Channel Slope 0.005000 ft/ft Bottom Width 5.00 ft ' Discharge r� 6.50 cfs Results t Depth 0.33 ft < O . S O,K . Flow Area 1.67 ft2 Wetted Perimeter 5.67 ft ' Top Width 5.00 ft Critical Depth 0.37 ft Critical Slope 0.003507 ft/ft ' Velocity 3.88 ft/s G 5'r+15 Ov— Velocity Head 0.23 ft Specific Energy 0.57 ft ' Froude Number 1.18 Flow is supercritical. 1 1 O6/28/00 FlowMaster v5.15 ' 09:31:50 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 ' DebiSn Vo;nt A ' Timberline Rd Curb Cut - 100-yr Storm Worksheet for Rectangular Channel ' Project Description Project File x:\916403 - rigden farm\drainage\projectl.fm2 ' Worksheet Flow Element Timberline curb cut Rectangular Channel Method Manning's Formula For Channel Depth tSolve Input Data ' Mannings Coefficient 0.012 Channel Slope 0.005000 fUft Bottom Width 5.00 ft Discharge 18.20 cfs = Qtoo yr Results ' Depth 0.65 ft ? p,5'-k - -now to*Ak Oveh-A-0p Flow Area 3.24 ftz cu-W GJAr— Wetted Perimeter 6.30 ft Top Width 5.00 ft Critical Depth 0.74 ft Critical Slope 0.003277 ft/ft ' Velocity 5.62 ft/s Velocity Head 0.49 ft Specific Energy 1.14 ft ' Froude Number 1.23 Flow is supercritical. 1 11 06/28/00 FlcwMaster v5.15 ' 09:32:09 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 vesi 5r k%AA- A Timberline Rd Curb Cut - Max. Capacity Worksheet for Rectangular Channel Project Description Project File x:\916403 - rigden farm\drainage\project1.fm2 Worksheet Timberline curb cut Flow Element Rectangular Channel Method Manning's Formula Solve For Discharge Input Data Mannings Coefficient 0.012 Channel Slope 0.005000 ft/ft Depth 0.50 ft Bottom Width 5.00 ft Results Discharge 12.21 cfs = Flow Area 2.50 ftz Wetted Perimeter 6.00 ft Top Width 5.00 ft Critical Depth 0.57 ft Critical Slope 0.003328 ft/ft Velocity 4.88 ft/s Velocity Head 0.37 ft Specific Energy 0.87 ft Froude Number 1.22 Flow is supercritical. MO,.x. Ccc�ac t 5' Gcsrh Gh�4 06/28/00 FlowMaster v5.15 ' 09:32:33 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 ' LOCATION: TIMBERLINE ROAD 6Jul-99 ITEM: OVERFLOW OVER SIDEWALK AT LOW POINT �O A COMPUTATIONS BY: JPZ ' SUBMITTED BY: JR ENGINEERING ' LP ON TIMBERLINE - Design Point a Design flow (100yr) = 18.2 cis Flow through 5' sidewalk chase = 12.2 cis, max capacity Flow needed over sidewalk = 6 cis ' Determine length of sidewalk where overtopping will occur and the height of water above the sidewalk by approximating the situation with weir flow. 1 Equation for flow over a weir: Q = KL sgrt(2g) 1-1312 Eq. 4-38, Hydraulic Engineering where K = flow coefficient of the weir N ' = 0.40 + 0.05 HIP, max HIP = 10 H = overflow height P P = height of weir L = length of the weir ' g = acceleration of gravity = 32.2 fVS2 set max. flow depth = 0.15 in, flow depth over walk ' P = 0.67 in, total sump depth K = 0.41 Take into account the geometry of the road - see cross section 30+00 for sidewalk elev. ' divide weir flow into discrete sections, each DL in length D Q A AQ = KAL sgrt(2g) H312 Total Q = E AQ ' PVT TBW =top back of walk 'Pro�i ve 1 1 1 1 1 Remarks station AL (ft) S full FL Elev. (ft) TBW Elev. (ft) Water elev. H (ft) Havg (ft) AQ (cfs) 29+52.73 -0.40% 31.70 32.80 32.75 -0.05 29+62.73 10.00 -0.40% 31.66 32.76 32.75 -0.01 -0.03 0.00 29+72.73 10.00 -0.40% 31.62 32.72 32.75 0.03 0.01 0.03 29+82.73 10.00 -0.40% 31.58 32.68 32.75 0.07 0.05 0.37 29+92.73 10.00 -0.40% 31.54 32.64 32.75 0.11 0.09 0.89 low point - PVI 30+02.73 10.00 -0.40% 31.50 32.60 32.75 0.15 0.13 1.55 30+12.73 10.00 0.47% 31.55 32.65 32.75 0.10 0.1265 1.48 30+22.73 10.00 0.40% 31.59 32.69 32.75 0.06 0.083 0.79 30+32.73 10.00 0.40% 31.63 32.73 32.75 0.02 0.043 0.29 30+42.73 10.00 0.40% 31.66 32.76 32.75 -0.01 0.07 0.61 30+52.73 10.00 0.40% 31.71 32.81 32.75 -0.06 0.023 0.12 130+62.731 10.00 1 0.40% 1 31.75 1 32.85 1 32.75 1 -0.10 1 -0.017 0.00 Total Q = 6.13 cfs carried over the sidewalk Actual Water elev = 32.75 ft Actual length of weir = 80 ft ponding depth at FL = 1.25 ft < 1.5 ft (18") max. allowable during 100-yr storm - o.k. ' overtopweir.XLS Swale K-K from DP a to Rigden Pond 212 ' Worksheet for Trapezoidal Channel ' Project Description Project File x:\916403 - rigden farm\drainage\swales.fm2 Worksheet Swale Timberline Rd. to Pond ' Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth 1 Input Data ' Mannings Coefficient 0.060 Channel Slope 0.007000 ft/ft Left Side Slope 4.000000 H : V ' Right Side Slope 4.000000 H : V Bottom Width 10.00 ft Discharge 24.20 cfs = 1-33% 1 Results Depth 1.00 ft ' Flow Area 13.95 ft2 Wetted Perimeter 18.23 ft Top Width 17.98 ft ' Critical Depth 0.53 ft Critical Slope 0.069376 ft/ft ' Velocity Velocity Head 1.73 ft/s 0.05 ft Specific Energy 1.04 ft Froude Number 0.35 ' Flow is subcritical. ' Notes: Q(100) x 133% ' Flow from Basins 107 and 108d For depths < 2.0' use "n" = 0.060 '05/05/00 FlowMaster v5.15 09:42:13 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 I 1 Swale from DP a to Rigden Pond 212 Cross Section for Trapezoidal Channel Project Description Project File x:\916403 - rigden farm\drainage\swales.fm2 Worksheet Swale Timberline Rd. to Pond Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Section Data ' Mannings Coefficient 0.060 Channel Slope 0.007000 ft/ft Depth 1.00 ft ' Left Side Slope 4.000000 H : V Right Side Slope 4.000000 H : V Bottom Width 10.00 ft ' Discharge 24.20 cfs 1 ' 10.00 ft 1.00 ft 1 L V H 1 NTS '05/05/00 09:42:27 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 FlowMaster v5.15 Page 1 of 1 Timberline irrigation swale Cross Section for Triangular Channel Project Description Project File x:\916403 - rigden farm\acad\timberline & drake\drainage\fm.fm2 ' Worksheet Flow Element sideroad swales Triangular Channel Method Manning's Formula Solve For Discharge ' 1 I 1 1 1 1 �J 1 0 1 1 1 Section Data Mannings Coefficient 0.060 Channel Slope 0.006000 ft/ft Depth 1.60 ft Left Side Slope 2.000000 H: V Right Side Slope 2.000000 H : V Discharge 7.86 cfs Saw,e oJ.eom-e,1Y1 � �OJI do C1 -WV1 1 .y C4s ivl ok 4-y t0-�Y Yv> 1 06/28/00 ' 09:26:37 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 1.60 ft 1 V L H 1 NTS FlowMaster v5.15 Page 1 of 1 TIMBERLINE SWALE Worksheet for Triangular Channel Project Description Project File x:\916403 - rigden farm\acad\timberline & drake\drainage\fm.fm2 ' Worksheet Flow Element sideroad swales Triangular Channel Method Manning's Formula Solve For Discharge ' Input Data ' Mannings Coefficient 0.060 Channel Slope 0.006000 ft/ft Depth 1.60 ft ' Left Side Slope 2.000000 H : V Right Side Slope 2.000000 H : V ' Results Discharge 7.86 cfs Flow Area 5.12 ft2 Wetted Perimeter 7.16 ft Top Width 6.40 ft Critical Depth 0.99 ft ' Critical Slope 0.076905 ft/ft Velocity 1.53 ft/s Velocity Head 0.04 ft ' Specific Energy 1.64 ft Froude Number 0.30 Flow is subcritical. 1 06/28/00 FlowMaster v5.15 ' 09:20:16 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Drake swale Cross Section for Triangular Channel Project Description Project File x:\916403 - rigden farm\acad\timberline & drake\drainage\fm.fm2 Worksheet sideroad swales ' Flow Element Triangular Channel Method Manning's Formula Solve For Discharge Section Data ' Mannings Coefficient 0.060 Channel Slope 0.006000 ft/ft Depth 2.00 ft Left Side Slope 4.000000 H : V ' Right Side Slope 4.000000 H : V Discharge 30.08 cfs 1 06/28/00 02:21:46 PM QS. 'LL 5 CbO-Si Vt ?J� cc,-Pac-�In Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 2.00 ft 1 V N H 1 NTS FlowMaster v5.15 Page 1 of 1 DRAKE SWALE ' Worksheet for Triangular Channel Project Description Project File x:\916403 - rigden farm\acad\timberline & drake\drainage\fm.fm2 Worksheet sideroad swales Flow Element Triangular Channel Method Manning's Formula Solve For Discharge Input Data ' Mannings Coefficient 0.060 Channel Slope 0.006000 ft/ft Depth 2.00 ft ' Left Side Slope 4.000000 H : V Right Side Slope 4.000000 H : V ' Results Discharge 30.08 cfs Flow Area 16.00 ftz ' Wetted Perimeter 16.49 ft Top Width 16.00 ft Critical Depth 1.29 ft ' Critical Slope 0.063289 ft/ft Velocity 1.88 ft/s ' Velocity Head Specific Energy 0.05 ft 2.05 ft Froude Number 0.33 Flow is subcritical. ' I 06/28/00 FlowMaster v5.15 02:21:38 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 6/28/00 RIPRAP CALCULATIONS LOCATION: TIMBERLINE & DRAKE PROJECT NO: 9164.03 COMPUTATIONS BY: J. ZUNG SUBMITTED BY: JR ENGINEERING DATE: 3/21 /00 Riprap requirements for a stable channel lining are based on the equation from Storm Drainage Design Criteria, City of Fort Collins, CO, May 1984 V So'17 = 5.8 (d5o) . (Ss - 1) . where: V = mean channel velocity (ftls) S = longitudinal channel slope (fUft) Ss = specific gravity of rock (minimum SS = 2.50) d5o = rock size in feet for which 50 percent of the riprap by weight is smaller Determine if riprap is required using Table 8-2 Design Point A - exit from sidewalk culvert V = 3.2 ft/s F = 0.78 S = 0.01 ft/ft F < 0.8 ? TRUE Ss = 2.5 V So." = 1.12 Using Table 8-2, Class 0 Riprap is required No riprap is required Design Point B - downstream of end of curb and gutter V = 5.1 ft/s F = 1.7 S = 0.2 ft/ft F < 0.8 ? FALSE Ss = 2.5 V S° 17 = 2.97 (S�s9- Using Table 8-2, Class 6 Riprap is required Use Class 12 Riprap since Frounde no. greater than 0.8. timberRIPRAPALS EXIT FROM SIDEWALK CULVERT DESIGN PNT A Worksheet for Trapezoidal Channel Project Description Project File x:\916403 - rigden farm\acad\timberline & drake\drainage\fm.fm2 Worksheet EXIT FROM SIDWALK CULVERT DESIGN POINT A Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth Input Data Mannings Coefficient 0.030 Channel Slope 0.010000 ft/ft Left Side Slope 4.000000 H : V ' Right Side Slope 4.000000 H : V Bottom Width 5.00 ft Discharge 18.20 cfs = R%00 1 [1 �J Results Depth 0.72 ft Flow Area 5.69 ftz Wetted Perimeter 10.95 ft Top Width 10.77 ft Critical Depth 0.62 ft Critical Slope 0.017230 ft/ft Velocity 3.20 ft/s — LkK 4vy Velocity Head 0.16 ft Specific Energy 0.88 ft Froude Number 0.78 �- Flow is subcritical. r 1prc p &,tc S . 06/28/00 FlowMaster v5.15 09:35:26 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 - Page 1 of 1 RUNDOWN FROM DESIGN POINT B ' Worksheet for Trapezoidal Channel ' Project Description Project File x:\916403 - rigden farm\acad\timberline & drake\drainage\fm.fm2 Worksheet RUNDOWN FROM DESIGN POINT B ' Flow Element Trapezoidal Channel Method Manning's Formula Solve For Channel Depth _ Input Data Mannings Coefficient 0.030 Channel Slope 0.200000 ft/ft Left Side Slope 10.000000 H : V ' Right Side Slope 10.000000 H : V Bottom Width 8.00 ft Discharge 6.00 cfs = Q too Results Depth 0.13 ft 1 Flow Area 1.17 ft2 Wetted Perimeter 10.54 ft Top Width 10.53 ft Critical Depth 0.23 ft Critical Slope 0.022831 ft/ft ' Velocity Velocity Head n 5.12 ft/s USL �� ro rap CC CS 0.41 ft / Specific Energy 0.53 ft Froude Number 2,71 Flow is supercritical. 1 06/28/00 FlowMaster v5.15 ' 09:35:39 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 PIPE AT DESIGN POINT C ' Worksheet for Circular Channel Project Description Project File x:\916403 - rigden farm\acad\timberline & drake\drainage\fm.fm2 Worksheet PIPE AT DESIGN POINT C ' Flow Element Circular Channel Method Manning's Formula Solve For Channel Depth Input Data ' Mannings Coefficient 0.013 Channel Slope 0.014000 ft/ft Diameter 24.00 in Discharge 28.00 cfs Results ' Depth 20.9 in Flow Area 2.90 ft2 Wetted Perimeter 4.80 ft Top Width 1.35 ft Critical Depth 1.83 ft Percent Full ' 86.88 Critical Slope 0.013343 ft/ft Velocity 9.66 ft/s ' Velocity Head Specific Energy 1.45 3.19 ft ft Froude Number 1.16 Maximum Discharge 28,79 cfs Full Flow Capacity 26.77 cfs Full Flow Slope 0.015321 ft/ft Flow is supercritical. 1 1 06/28/00 FlowMaster v5.15 09:35:54 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 Page 1 of 1 Ci44 04 Fort Co 1(1nS Table 8-1 CLASSIFICATION AND GRADATION OF ORDINARY RIPRAP 8 of Total Weight Smaller than the Stone Size dSA Riprap Designation Given Size (in pounds) (inches) 70 100 85 Class 6tt 50-70 35 35-50 10 6 2-10 <1 70-100 440 Class 12 50-70 275 35-50 85 12 2-10 3 100 1275 Class 18 50-70 655 35-50 275 18 2-10 10 100 3500 Class 24 50-70 1700 35-50 655 29 2-10 35 Table 8-2 RIPP.AP REQunua4F2IT5 FOR CEp-*Ih'EL I.ZI.Z2:GSj'f VS°'17/ (S -1) o.cct. Roc]c Typet-f 0 to 1.4 No Riprap Required 1.5 to 4.0 Class 6 Riprap 4.1 to 5.8 Class 12 Riprap 5.9 to 7.1 Class 18 Riprap 7.2 to 8.2 Class 24 Riprap t'Ose Sc=2.5 unless the source of rock and its.densities are known at the time of design. ttTable valid only for Froude number of 0.8 or less and side slopes no steeper than 2h_ly. I u 1 [1 1 DRAINAGE CRITERIA MANUAL MAJOR DRAINAGE Table 5-4 THICKNESS REQUIREMENTS FOR GRANULAR BEDDING Minimum Bedding Thickness (Inches) Riprap Fine Grained Soils* Designation Course Grained Soils** Ty pe I Type II Type 11 L, G, SM 4 4 6 M 4 4 6 H 4 6 8 VH 4 6 8 *May substitute one 12 inch layer of Type II bedding. Substitution of one layer of Type II bedding shall not be permitted at drop structures. Use of a combination of filter fabric and Type II bedding at drop structures is acceptable, see Section 5.3.2 for use of filter fabric at drop structures. **Fifty percent or more by weight retained on the #40 sieve. 5.3.2 Filter Fabric Filter fabric is not a complete substitute for granular bedding. Filter fabric provides filtering action only perpendicular to the fabric and has only a single equivalent pore opening between the channel bed and the riprap. Filter fabric has a relatively smooth surface which provides less resistance to stone movement. As a result, it is recommended the use of filter fabric be restricted to slopes no steeper than 2.5h to Iv. Tears in the fabric greatly reduce its effectiveness so that direct dumping of riprap on the filter fabric is not allowed and due care must be exercised during construction. None- theless, filter fabric has proven to be an adequate replacement for granular bedding in many instances. Filter fabric provides an ade- quate bedding for channel linings along uniform mild sloping channels where leaching forces are primarily perpendicular to the fabric. At drop structures and sloped channel drops, where seepage forces may run parallel with the fabric and cause piping along the bottom surface of the fabric, special care is required in the use of filter 11-15-82 ' JR Engineering, Ltd. 2620 E. Prospect Rd., Ste. 190, Fort Collins, CO 80525 1 11 RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: TIMBERLINE ROAD/DRAKE ROAD IMPROVEMENTS STANDARD FORM A COMPLETED BY: JPZ DATE: 05-May-00 DEVELOPED ERODIBD,r1'Y Asb Lsb Ssb At * LI Ai • S1 Lb Sb PS SUBBASIN(s) ZONE (AC) (FI) (%) (FI) (%) (%) A MODERATE 2.20 620 0.6 1364.0 1.2 B 0.70 570 0.6 399.0 0.4 C 4.37 1645 0.8 7188.7 3.6 Total 7.27 8951.65 5.23 1231 0.7 74.9% ' Asb = Sub -basin area Lsb = Sub -basin flow path length Ssb = Sub -basin slope Lb = Average flow path length = sum(Ai Li)/sum(Ai) Sb = Average slope = sum(Ai Si)/Sum (Ai) PS is taken from Table 8-a (Table 5.1, Erosion Control Reference Manual) by interpolation. An Erosion Control Plan will be developed to contain PS% of the rainfall sedimentation that would normally flow off a bare ground site during a 10-year, or less, precipitation event. 1 1 ' Erosion.xls JR Engineering 2620 E. Prospect Rd., Ste. 190, Fort Collins, CO 80525 EFFECTIVENESS CALCULATIONS PROJECT: TIMBERLINE ROAD/ DRAKE ROAD IMPROVEMENTS STANDARD FORM B COMPLETED BY: JPZ DATE: 05-May-00 EROSION CONTROL C-FACTOR P-FACTOR METHOD VALUE VALUE COMMENT BARE SOIL 1.00 1.00 SMOOTH CONDITION ROUGHENED GROUND 1.00 0.90 ROADS/WALKS 0.01 1.00 GRAVEL FILTERS 1.00 0.80 PLACED AT INLETS SILT FENCE 1.00 0.50 SEDIMENTTRAP 1.00 0.50 STRAW MULCH (S = 1-5%) 0.06 1.00 FROM TABLE 8B STRAW BARRIERS 1.00 0.80 EFF = (I-C*P)* 100 MAJOR SUB BASIN AREA EROSION CONTROL METHODS BASIN BASIN (Ac) A 2.20 ROADSIWALKS 1.80 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.40 Ac. SILT FENCE NET C-FACTOR 0.02 NET P-FACTOR 0.50 EFF = (1-C*P)*100 = 99.0'% B 0.70 ROADS/WALKS 0.58 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.12 Ac. SILT FENCE, STAW BARRIERS NET C-FACTOR 0.02 NET P-FACTOR 0.40 EFF = (I-C*P)* 100 = 99.3% C 4.37 ROADS/WALKS 4.37 Ac. ROUGHENED GR. 0.00 Ac. STRAW/MULCH 0.00 Ac. SILT FENCE, STAW BARRIERS NET C-FACTOR 0.01 NET P-FACTOR 0.40 EFF = (1-C*P)* 100 = 99.6% TOTAL AREA = 7.27 ac TOTAL EFF = 99.4% ( E (basin area * eff) / total area REQUIRED PS = 74.9'% Since 99.4 % > 74.9%, the proposed plan is o.k. TIMBEREROSION.XLS TIMBERLINE ROAD/DRAKE ROAD IMPROVEMENTS EROSION CONTROL COST ESTIMATE JOB NO. 9164.03 EROSION CONTROL MEASURES COMPLETED BY: RA ITEM DESCRIPTION UNITS I UNIT COST JQUANTITYI TOTAL COST 1 TEMPORARY SEED & MULCH ACRE $ 655.00 0.5 $ 340.60 2 SILT FENCE LF $ 3.00 1,600 $ 4,800.00 3 STRAW BALES BARRIER EACH $ 100.00 4 $ 400.00 4 INLET PROTECTION EACH $ 250.00 3 $ 750.00 COST $ 5,540.60 CITY RESEEDING COST FOR TOTAL SITE AREA ITEM DESCRIPTION UNITS I UNIT COST IQUANTITY I TOTAL COST 1 RESEEDULCH /M ACRE $ 615.00 7.3 $ 4,471.05 COST $ 4,471.05 SECURITY DEPOSIT $ 5,540.60 REQUIRED EROSION CONTROL SECURITY DEPOSIT WITH FACTOR OF 150% $ 8,310.90 Timberline Road 9164.03 Future Drainage Evaluation Timberline LP FL Elevation = 4,931.50 ft Approximate pipe length from Timberline to Pond = 1,650 ft Pond invert out = 4,919.72 ft (Rigden Pond 212) Run pipe from pond to Timberline at 0.3% slope, Resulting invert = 4,919.72 + 1,650*0.003 = 4,924.67 ft Room for pipe = 4,931.50 — 4,924.67 = 6.83 ft Set 2' clearance between FL elev and top of pipe leaves 4.83' for pipe 481, pipe = 4.4' including wall thickness. 481, pipe capacity = 92 cfs at 0.3%. 100 year runoff from basin 107 (from Rigden Farm Filing One PDP) = 50 cfs ----> should have adequate clearance and fall for future system XA916403 - Rigden Farm\Acad\Timberline & Drake\Drainage\Timberline Road9164.doc No Text