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HomeMy WebLinkAbout20081279.tiff • AG PRO PRO ■■ COMPLETE LAND & RESOURCE SOLUTIONS January 11, 2008 Hanna Hippely Weld County Planning 918 10 Street Greeley, CO 80631 RE: AgPro Job Number 1103-04, Weld County Amended USR#1405 Dear Hanna: Please find included the preliminary drainage report for the Aurora Milk Plant amended USR#1405. This is the plan and the specific details of the proposed improvements will not be developed until this project is approved by Weld County Planning Department. I have also provided a copy to Don Dunker in Public Works for his review. As always if either of you have any questions or concerns please done hesitate to contact me Sincerely, Ira _ertneky, EIT Agricultural Engineer • ENGINEERING, SURVEYING, PLANNING & CONSULTING 4350 Highway 66 Longmont,CO 80504 970.535.9318 / office 303.485.7838/metro 970.535.9854/fax www.agpros.com AGYROfp'sireaL,LLC 2008-1279 Preliminary Drainage Report (change of zone drainage report) Prepared for: Aurora Dairy Corporation Milk Plant Lot A of Pending RE - 4654 being part of the northeast 1/4 Section 30, Township 3 N, Range 67 W. Platteville, Colorado • January 11, 2008 Pre'ared b AG PRO • ENGINEERING, SURVEYING, PLANNING & CONSULTING 4350 Highway 66 Longmont, CO 80504 970.535.9318 /office 303.485.7838 /metro 970.535.9854/ fax www.agpros.com AGPRO(naionals,LLC Aurora Dairy Corporation Preliminary Drainage Report • TABLE OF CONTENTS CERTIFICATIONS 1 I. GENERAL LOCATION AND DESCRIPTION 2 A) PROJECT DESCRIPTION 2 B) LOCATION 2 C) DESCRIPTION OF PROPERTY 2 II. DRAINAGE BASINS AND SUB-BASINS 2 A) MAJOR BASIN DESCRIPTION 3 B) SUB-BASIN DESCRIPTION 3 III. DRAINAGE DESIGN CRITERIA 4 A) REGULATIONS 4 B) DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS 4 C) HYDROLOGICAL CRITERIA 4 D) HYDRAULIC CRITERIA 5 IV. DRAINAGE FACILITY DESIGN 5 • A) GENERAL CONCEPT 5 B) SPECIFIC DETAILS 6 V. CONCLUSIONS 7 A) COMPLIANCE WITH THE WCSDC 7 B) DRAINAGE CONCEPT 7 VI. REFERENCES 7 VII. APPENDICES 7 • 1/11/2008 AGPROfessionals, LLC ii Aurora Dairy Corporation Preliminary Drainage Report S Certifications I hereby certify that this report for the conceptual drainage design of Aurora Milk Plant was prepared under my direct supervision in accordance with the provisions of the Weld County storm drainage criteria for the owners thereof.•V . • / • Travis l rtneky, EIT Roger T. Sterling, P. E. • 1/11/2008 AGPROfessionals, LLC 1 Aurora Dairy Corporation Preliminary Drainage Report I. General Location and Description a) Project Description The Aurora Organic Dairy is proposing to expand their currently-operating milk processing facility located west of Platteville, Colorado. The existing facility consists of a milk processing plant surrounded by irrigated pasture. The proposed plan will expand the cold storage capabilities of the existing plant. Overall changes to the site including existing impervious areas will be minimal, Prior to the construction of the milk plant, the facility was operated as a feedlot with runoff generated from the site being collected in storm water retention ponds. The collected runoff was subsequently and-land applied to crop ground. Prior to the operation of the feedlot, the site appears to have been farmed as irrigated row crops. b) Location The physical address of the Aurora Dairy Milk Plant is 6788 Highway 66, Platteville, CO. The entrance to the facility located between CR 13 and CR 15.5 on the south side of Highway 66. The milk plant is located in the E'/ of the NE 1/4 of Section 30, Township 3 North, Range 67 West, of the 6th PM. The milk plant is approximately 1 mile north of the channel of the St. Vrain River,-and approximately 1.4 mile south east • of the Grand View Estates Subdivision. The USGS topographic map utilized for this report is based upon the NGVD-29 datum. Accordingly, the 2006 topographic data collected at the Aurora Dairy site must be raised 2.2 ft. to match the NGVD-29 datum. An existing irrigation ditch runs through the site and feeds three existing, private irrigation ponds. The first of those ponds is considerably large and is located east of the plant. The remaining ponds two irrigation ponds are under the control of Aurora Organic Dairy. c) Description of Property The milk plant property consists of approximately 19 acres and is located on the south side of Highway 66. Because the north property line of the site is located along the crest of a hill, run on to the site is inconsequential. The general topography of the site and adjacent areas drain directly to the St.Vrain River located approximately 1 mile south and at an elevation approximately 50ft lower than the lowest point on the site. This site surfacing is currently and will continue to be gravel, asphalt paving, roofed area and pasture. II. Drainage Basins and Sub-Basins The primary Drainage basin of this project is that of the St. Vrain River. The St. Vrain • is a tributary of the South Platte River. 1/11/2008 AGPROfessianals, LLC 2 Aurora Dairy Corporation Preliminary Drainage Report • a) Major Basin Description 1) Weld County Code: This site is a commercial development and all drainage plans and designs will conform to the Weld County Addendum to the Urban Storm Drainage Criteria Manuals. 2) Maior Basin Characteristics: The site is located in the major basin of the South Platte River and most directly the St. Vrain River. Both streams are mountain fed and maximum flows are typically observed during spring snowmelt. Peak rainfall events are usually of a short duration during the summer months. 3) Irrigation: As described previously in this report, a single small irrigation ditch bisects the subject site and feeds a number of privately owned and operated irrigation ponds. The first of those ponds is located east of the milk plant and provides irrigation water for land on the north side of Highway 66. That pond is not controlled by Aurora Dairy. Two additional ponds located on the property are under the direct control of Aurora Dairy. The first of those ponds is located adjacent to Highway 66 and is filled by mechanically pumping water into it. That pond is only used for short term storage to regulate flow from the ditch and to facilitate sprinkler irrigation. The second of those • ponds is located south and down-gradient from the milk plant. That pond is also utilized for irrigation storage while also receiving some stormwater runoff from the site. It is proposed that this pond be bisected with an earthen berm such that two impoundments will be created. One of those impoundments will be located on the south side of the berm and will serve as an irrigation pond. The southerly pond will be equipped with at pump station to deliver water to side roll sprinklers operated at the site. The impoundment located on the north side of the berm will be graded so as to provide stormwater retention for the site. 4) FEMA Flood Plain: No portion of this site lies within a mapped FEMA 100-yr floodplain. B) Sub-Basin Description 1) Historical Drainage Patterns: Historically, the subject site appears to have drained in a number of fashions. Currently, the site drains to a the previously-described irrigation pond located south of the milk plant or flows overland to the St. Vrain River. Prior to construction and operation of the milk plant, a feedlot was operated on the property with stormwater discharged to retention ponds. Prior to the operation of the feedlot, the site was farmed with irrigated row crops. It is proposed that stormwater released from the site be returned to native rangeland and vegetative filtering. • A minor portion of the site consisting mainly of the entry way to the property and located up-gradient from the irrigation ditch bisecting the site has historically drained into that ditch as well as to the previously-described irrigation pond not operated by Aurora Dairy. 1/11/2008 AGPROfessionals, LLC 3 Aurora Dairy Corporation Preliminary Drainage Report • 2) Off-site Drainage Flow Patterns: Because the site is located at the crest of a hill, it does not appear that there are any impacts to the property from off-site stormwater sources. III. Drainage Design Criteria A) Regulations The proposed Aurora Milk Plant expansion drainage plans will comply with Weld County design or performance requirements outlined in the Weld County Addendum to the Urban Drainage storm drainage criteria manual. B) Development Criteria Reference and Constraints Although some drainage infrastructure currently exists at the site, it does not appear that any previous studies have been conducted with respect to the property. The existing milk plant is guttered and has been constructed with a rudimentary storm sewer system to carry nuisance flows away from those areas immediately adjacent to the building. The existing storm sewer system drains to the previously-described irrigation pond located south of the milk plant. As described previously in this report, it is • proposed that this existing irrigation pond be modified to provide stormwater detention for the improved portions of the property in addition to maintaining an impoundment for irrigation storage. It is proposed that the existing storm water inlets to the pond remain in place and that the irrigation inlet be relocated to the south. The proposed retention pond will be over-designed to accommodate the runoff from the entrance area in the event that the adjacent properties are developed and the discharge path to the irrigation ditch is lost. C) Hydrological Criteria This site is located relatively close proximity to Denver and thus the UD&FCD maps may be used to determine the historic and proposed runoff criteria. The proposed system will be designed to capture the 100-year storm event and will release at the historic rate of the 5-year storm from the undeveloped site. The Urban Drainage/FAA rational method was used to determine design flows and storage capacities. Spreadsheets provided by the UDFCD were used to simplify the calculation of both the peak flows and detention requirement. Results were compared to NRCS (SCS) method TR-55 and NRCS (SCS) method EFH2. While the assumptions made for modeling by EFH2 may not be entirely valid in this case, it does serve to provide a comparison and check against the other methods employed to model runoff. • 1/11/2008 AGPROfessionals,LLC 4 Aurora Dairy Corporation Preliminary Drainage Report • D) Hydraulic Criteria The storm water detention design uses basic hydraulic models and calculations (e.g. Manning's Equation) that are well understood and do not require detailed description. The proposed detention ponds will be fitted with two different types of outlet structures. The northern detention pond capturing the entrance area runoff will utilize a perforated plate to retain the water quality control volume (WQCV). A weir located above the perforated plate will release at the 5-year event volume. The primary detention pond located south of the milk plant will utilize a drop box outlet incorporating an outlet structure consisting of an up-gradient perforated plate to retain the WQCV and a down-gradient orifice plate to discharge the 5-year event volume. Runoff volumes exceeding the 100-year event will be released over an emergency spillway sized to accommodate the 100-year runoff. IV. Drainage Facility Design A) General Concept For the purposes of this project, the property has been divided into two separate • drainages. The first of those drainages is the entry area to the site located above the irrigation ditch bisecting the property. The second primary drainage consists of the remaining portion of the site south of the irrigation ditch. The area above the irrigation ditch is relatively small and is identified as "entrance area" for the purposes of this discussion. It comprises less than 2 acres and storm water runoff will be controlled by creating a berm on the edge of the parking area and installing a flow control structure that will release water at a rate less than the 100-year peak volume resulting from the asphalted area. Because draining this area across the irrigation ditch may prove impractical, it is proposed to release runoff from the entrance area to the ditch as has historically occurred. In the event that the ditch is taken out of service in the future, the entrance area will drain in a southerly direction across the rest of this site and to the primary detention pond which will be sized to detain this additional runoff. The primary drainage area located below the entrance is approximately 13 acres in areal extent and does utilize some minor storm sewers to divert runoff to the existing pond located south of the milk plant. Those storm sewers catch the roof runoff and a small area adjacent to the building itself. It is proposed to create a detention pond for the site by berming off the southern-most end of the trailer parking area and extending that berm across the existing irrigation pond located south of the milk plant. The result will be to create a detention for stormwater exclusively. • Due to the physical features of the existing irrigation pond and truck parking area, it appears that the proposed detention pond will likely be much larger than would be required to retain a 100-year rainfall event. The proposed detention pond pond will 1/11/2008 AGPROfessionals, LLC 5 Aurora Dairy Corporation Preliminary Drainage Report • discharge across the pasture area located south of the pond and flow overland to the St. Vrain River. A distribution device will be constructed over the top of the berm to evenly apply the discharge across the pasture. Discharging across the pasture will allow for filtering of the runoff thereby reducing potential pollutants and reducing the discharge volume. It is not anticipated that any variances from the Weld county codes will be required at this time. Drawing DR-1 depicts the proposed site conditions and the locations of proposed structures. 8) Specific Details The proposed storm water management system will consist almost entirerly of overland flow to the detention pond. The proposed grading plan will ensure that positive drainage exists in all locations. No additional storm sewers or closed conveyances will be constructed. By conducting the anticipated runoff overland, maintenance issues associated with drainage facilities such as buried storm sewers will be precluded. Because a large portion of the site will be finished with gravel surfacing, buried conduits could prove to be problematic. It is anticipated that particulates resulting from erosion of the gravel surfacing will settle out in the over-sized detention basin. Because the detention basin will be oversized, it is not anticipated that sedimentation of pond will pose a significant issue. However, in the event that significant sedimentation does • occur, the design volume may be restored by excavation of those deposits. The interval of the detention basin requiring sediment removal has not been determined. The basin will remain under the same ownership of the milk plant and any required maintenance of the system will be conducted by the milk plant owner. The required volume of the proposed primary storm water detention pond has been calculated to be 2.2 acre feet. The grades shown on the attached drawing DR-1 reflect a capacity of 4.1 acre feet and may be downsized when the final design is complete. The discharge will be piped from the drop inlet structure to a location along the western edge of the facility where it will be released. This point of discharge is the beginning point of the proposed drainage easement. The discharge point will be constructed with a flat concrete distributor to evenly apply the runoff to the adjacent pasture as previously discussed. It cannot be guaranteed that this adjacent property will remain as a pasture, and under the control of Aurora Organic Dairy. A drainage easement will be established along the western most property line that will extend to the St. Vrain River. If the current pasture is developed in the future, the discharge can either be piped along the easement, or an open channel drainage can be established, whichever suites the eventual development. Due to the excess capacity of the detention pond we will likely release the discharge at a • rate less than the historic 5yr but will not release greater than that. An emergency spillway will be installed in this lower detention pond to protect against any potential storm overtopping and breaching the berm. The system will not have any functioning 1/11/2008 AGPROfessionals, LLC 6 Aurora Dairy Corporation Preliminary Drainage Report • components that will need maintenance in order to ensure the system is safe and functioning. The only maintenance required will be the control of vegetation on the detention basin and to ensure that the flow control inlets are clean. This site lies within the Denver area urban flood control district and therefore the precipitation depth duration frequency maps from the Urban Storm Drainage Criteria Manual will be used to determine the appropriate runoff volumes and rates. V. Conclusions A) Compliance with the WCSDC The proposed storm water drainage system was designed to with the guidelines or design standards outlined in the Weld County Storm Drainage criteria. B) Drainage Concept The proposed storm water drainage system will effectively control all runoff from the Aurora Organic Dairy milk plant. All runoff from the property will enter a detention basin that was sized using the Urban Drainage and Flood control District criteria. The runoff will be detained to reduce the pollutant loading and peak runoff rate. The detention basins are sized to have a capacity in excess of the 100-year storm and release • at a peak flow equal to the 5-year historic rate. The peak runoff from this site after the development will be substantially less than it has been since the site was originally settled. This decrease in peak runoff will lessen the downstream loading on both the St. Vrain and South Platte Rivers. VI. References A) Weld County Storm Drainage Criteria Addendum to the Urban Storm Drainage Criteria Manuals, October 2006 B) Urban Storm Drainage and Flood Control District Criteria Manual, revised June 2007 C) NRCS TR-55, Urban Hydrology for Small Watersheds, June 1986 VII. Appendices A) Runoff Design Summary Table B) Weighted Percent Impervious C) Calculation of Peak Runoff, Historical Conditions, Main D) Calculation of Peak Runoff, Historical Conditions, Entrance E) Detention Volume by FAA and Modified FAA Method, Main F) Detention Volume by FAA and Modified FAA Method, Entrance G) Runoff Model Comparison Table • H) Preliminary Report Drainage Report Drawing, DR-1 1/11/2008 AGPROfessionals,LLC 7 • Aurora Milk Plant 1/7/2008 Runoff Design Summary Proposed Main Area Entrance FAA FAA Area 13.0 ac 1.6 ac P2 0.95 in 0.95 in P5 1.35 in 1.35 in P10 1.63 in 1.63 in P100 2.65 in 2.65 in Percent Impery 72.42 % 58 % Avg s 0.05 ft/ft 0.015 fUft Tc 0.167 0.18 C10 0.55 0.37 C100 0.64 0.5 Q10 31.32 cfs 2.43 cfs Q100 59.82 cfs 5.35 cfs Storage Volume 2.201 ac-ft 0.191 ac-ft Historic Main Area Entrance FAA Pasture FAA Pasture Area 13.0 ac 13.0 ac P2 0.95 in 0.95 in • P5 1.35 in 1.35 in P10 1.63 in 1.63 in P100 2.65 in 2.65 in Percent Impery 2 °/ci 2 % Avg s 0.05 ft/ft 0.05 fUft Tc 14 14 Q5 2.32 cfs 0.35 cfs Q10 7.36 cfs cfs Q100 28.17 cfs cfs 411 • Weighted Percent Impervious Aurora Milk Plant 1/4/2008 Main Area I a Area(sf! Area ac Ia x a (la)weighted Roof 90 97,970 2.25 202.42 Pavement 100 324,122 7.44 744.08 Gravel 40 assume 0 0.00 0.00 Vegetated 0 147,209 3.38 0.00 Total 569,301 13.07 946.50 72.42 Main Area I a As fin Area(ac) (la)x(a),(la)weighted Pavement 100 22,769 0.52 52.27 Gravel 40 17,697 0.41 16.25 Vegetated 0 29,230 0.67 0.00 Total 69,696 1.60 68.52 42.83 ) • • • CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: Aurora Milk Plant,Historic Conditions Catchment ID: Main I. Catchment Hydrologic Data Catchment ID= Main Area= 13.07 Acres Percent Imperviousness= 2.00 NRCS Soil Type= B A, B,C,or D II. Rainfall Information I(inch/hr)=C1 •P1/(C2•Td)"C3 Design Storm Retum Period,Tr= 5 years (input return period for design storm) C1 = 28.50 (input the value of C1) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1= 1.35 inches (input one-hr precipitation--see Sheet"Design Info") III. Analysis of Flow Time(Time of Concentration)for a Catchmen Runoff Coefficient,C= 0.08 Overide Runoff Coefficient,C= (enter an overide C value if desired,or leave blank to accept calculated C.) 5-yr.Runoff Coefficient,C-5= 0.08 Overide 5-yr.Runoff Coefficient,C= (enter an overide C-5 value if desired,or leave blank to accept calculated C-5.) Illustration i •- clad • LEGEND Reach I flow Reach 2• O Beghming now Direction • E Catchment Reach Boundary NRCS Land Heavy Tillage/ Short Nearly Grassed Paved Areas S. Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways (Sheet Flow) I Conveyance IM 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ft/ft ft C-5 fps minutes input input output input output output Overland 0.0500 100 0.08 N/A 0.15 10.81 1 0.0500 600 2.50 0.56 17.89 2 3 4 5 Sum 700 Computed Tc= 28.70 Regional Tc= 13.89 User-Entered Tc= 13.89 IV. Peak Runoff Prediction Rainfall Intensity at Computed lc,I= 2.17 inch/hr Peak Flowrate, Op= 2.32 cfs Rainfall Intensity at Regional 1c, I= 3.18 inch/hr Peak Flowrate,Qp= 3.39 cfs • Rainfall Intensity at User-Defined 1c,I= 3.18 inch/hr Peak Flowrate,Op= 3.39 cfs UD-Rational v1.02a historic main.xls,Tc and PeakQ 1/4/2008,4:30 PM • CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Project Title: Aurora Milk Plant,Historic Conditions Catchment ID: Entrance I. Catchment Hydrologic Data Catchment ID= Entrance Area= 1.60 Acres Percent Imperviousness= 2.00 NRCS Soil Type= B A, B,C,or D II. Rainfall Information I(inch/hr)=C1 'P1/(C2+Td)AC3 Design Storm Return Period,Tr= 5 years (input return period for design storm) C1 = 28.50 (input the value of C1) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1= 1.35 inches (input one-hr precipitation--see Sheet"Design Info") III.Analysis of Flow Time(Time of Concentration)for a Catchmen Runoff Coefficient,C= 0.08 Overide Runoff Coefficient,C= (enter an overide C value if desired,or leave blank to accept calculated C.) 5-yr. Runoff Coefficient,C-5= 0.08 Overide 5-yr. Runoff Coefficient,C= (enter an overide C-5 value if desired,or leave blank to accept calculated C-5.) Illustration • overland • LEGEND Reach I flow Reach 2• O Begirmi d Flow Direction Catchnant Reach Boundary NRCS Land Heavy Tillage/ Short Nearly Grassed Paved Areas& Type Meadow Field Pasture/ Bare Swales/ Shallow Paved Swales Lawns Ground Waterways (Sheet Flow) Conveyance I 2.5 5 7 10 15 20 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ft/ft ft C-5 fps minutes input input output input output output Overland 0.0500 50 0.08 N/A 0.11 7.64 1 0.0500 400 2.50 0.56 11.93 2 3 4 5 Sum 450 Computed Tc= 19.57 Regional Tc= 12.50 User-Entered Tc= 12.50 IV. Peak Runoff Prediction Rainfall Intensity at Computed lc, I= 2.69 inch/hr Peak Flowrate,Qp= 0.35 cfs Rainfall Intensity at Regional lc,I= 3.33 inch/hr Peak Flowrate,Qp= 0.43 cfs • Rainfall Intensity at User-Defined-c,I= 3.33 inch/hr Peak Flowrate,Op= 0.43 cfs UD-Rational v1.02a historic Entrance.xls,Tc and PeakQ 1/4/2008,4:28 PM MINOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD • (See USDCM Volume I Runoff Chapter for description of method) Project:Aurora Milk Plant Basin ID:Main Basin (For catchments less than 160 acres only. For larger catchments,use hydrograph routing method) (Note:for catchments larger than 90 acres,CUHP hydrograph and routing are recommended) The user must fill In all of the blue cells for these sheets to function. Design Information(Input): Catchment Drainage Imperviousness I.= 72.42 percent Catchment Drainage Area A= 130700 acres Predevalopment MRCS Soil Group Type= 8 A,B,C,or D Return Period for Detention Control T= 10 years(2,5,10,25,50,or 100) Time of Concentration of Watershed Tc= 10 minutes Allowable Unit Release Rate(See Table A) q= 0.16 c(s/acre One-hour Precipitation PI= 163 inches Design Rainfall IDF Formula I=Cl'171/(C24Tcy.C3 Coefficient One CI= 2850 Coefficient Two 02= 10.00 Coefficient Three Cs= 0.79 —__I Determination of Average Outflow from the Basin(Calculated): Runoff Coefficient C= 0.55 Inflow Peak Runoff Op-in= 31.32 cis Allowable Peak Outflow Rate Op-out= 2.32 cis Ratio of Op-outlOp-in Ratio= 0.07 Determination of MINOR Detention Volume Using FAA&Modified FAA Method 5 r-Enter Rainfall Duration Incremental Increase Value Here(e.g_5 for 5-Minutes) Rainfall Rainfall Inflow Average Outflow Storage Adjustment Average Outflow Storage Duration Intensity Volume Outflow Volume Volume Factor Outflow Volume Volume minutes inches/hr cubic feet (FAA,cis) (FM,cf) (FAA,cO (Modified) (Mod,cfs) (Mod.ci (Mod cf (input) (output) (output) (Output) (output) (output) (output) (output) (output) (output) III 0 0.00 0 0.00 0 0 0.00 0.00 0 0 5 6.47 11,785 122 387 11,427 1.00 2.32 BBB 11,090 10 4.38 18,794 1.22 795 16,059 1.00 232 1,302 17,402 15 3.65 23,834 1.22 1,102 22,532 0.83 1.93 1,740 21,894 20 3.18 27,285 122 1,488 25.618 0.75 1.74 2,088 25,107 25 2.60 30,198 122 1,637 28,369 0.70 122 2,438 27,760 30 2.52 82207 1.22 2,204 30,403 0.67 1.55 2,784 29,823 35 2.30 34,8112 122 2,571 32,091 0.84 1.49 9,132 31,530 40 2.11 38,450 122 2,939 &3,511 0,83 1.45 3,480 22,970 45 1.98 38,032 1.22 3,306 34,728 0.81 1.42 3,828 34,204 50 1.53 39,450 1.22 3,873 35,777 080 1.30 4,176 35,274 55 1/2 40,738 122 4,041 311,696 029 1.97 4,524 38,212 80 1.82 41,013 122 4,408 37,606 0.58 1.85 4,872 37,041 85 1.59 42,097 1.22 4,775 38222 0.58 1.34 5,220 37,777 70 1.48 44,003 122 5,149 38,880 0.57 1.39 5,585 38,435 75 1.89 44,941 122 5,510 39,431 0,57 1.91 5,916 39,025 80 1.33 45,821 122 5,877 30,043 0.53 1.31 8,284 39257 e5 1.27 46,649 122 6245 40,404 0.58 1.30 8,812 40,037 90 122 47,431 122 8,812 40,819 026 129 8,080 40,471 95 1.18 48,178 122 6,979 41,104 025 126 7,308 40,885 100 1.13 48,879 1.22 7,347 41,632 095 128 7,556 41,223 105 1.09 49,552 122 7,714 41,838 025 1.27 8,004 41,546 110 1.08 50,195 122 5,081 42,114 025 127 8,352 41,643 115 1.02 60,811 122 8,449 42,383 0.54 126 8,700 42,111 120 0.99 51,403 122 8,818 42,557 024 125 9,048 42,855 125 088 51,972 122 0,153 42,789 024 125 9,396 42,576 130 0.94 52,520 122 9,551 42,999 0.54 1.25 9,744 42,778 135 0.91 53,049 122 9,918 43,131 0.54 125 10,092 42,957 140 0.89 53,580 122 10,265 43274 0.54 124 10,440 43,120 145 0.88 64,054 122 10,853 43,401 0.53 124 10,786 43,288 150 0.84 64,533 122 11,020 43,513 0.53 124 11,136 43,397 155 0.82 54,907 122 11,387 43,610 023 123 11,484 43,513 180 0.80 65,448 122 11,755 43,894 0.53 123 11,832 43,815 165 0.79 55,8B6 122 12,122 43,784 023 123 12,160 43,706 170 0.77 58,313 122 12,469 43,828 023 123 12,628 43,785 175 0.75 58,728 122 12,857 43,871 023 123 12,878 43,652 180 0.74 57,132 122 13,224 43,908 023 122 13,224 43,908 • FAA Minor Storage Volume(cubic ft.)= 43908 Mod,FAA Minor Storage Volume(cubic M1.)• 43,908 FAA Minor Storage Volume(acre-M1.)- 1.0080 Mod.FAA Minor Storage Volume(acre-n.)• 1.0080 UDFCD DETENTION VOLUME ESTIMATING YWRKBOOK Version 2.02,Released January 2007 UD-Delention_v2 02 main vls,Modified FAA 1/4/2008,4'.31 PM MINOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD • (See USDCM Volume I Runoff Chapter for description of method) Project: Aurora Milk Plant Basin ID: Main Basin Inflow and Outflow Volumes vs. Rainfall Duration Intersection of Modified and FAA Outflow Plots is at maximum detention volume 60,000 50,000 40,000 u o • u. 30,000 - - 20,000 "_ 10,000 - -1 - - 0 0 20 40 60 80 100 120 140 160 180 200 Duration(Minutes) f Inflow Volume —*—Modlfled Outflow Volume t FAA Outflow Volume • UDFCD DETENTION VOLUME ESTIMATING WORKBOOK Version 2.02,Released January 2007 11D-Detention v2 02 main uls,Modified FAA 1/4/2008,4.31 PM MAJOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD . (See USDCM Volume I Runoff Chapter for description of method) Project:Aurora Milk Plant Basin ID:Main Basin (For catchments less than 160 acres only. For larger catchments,use hydrograph routing method) (Note:for catchments larger than 90 acres,CUHP hydrograph and routing are recommended) The user must fill in all of the blue cells for these sheets to function. Design Information(Input): Catchment Drainage Imperviousness 1.= 7242 percent Catchment Drainage Area A= 13.0700 acres Predevelopment NRCS Soil Group Type= B A,B,C,or D Return Period for Detention Control T= 100 years(2,5,10,25,50,or 100) Time of Concentration of Watershed Tc= 10 minutes Allowable Unit Release Rate(See Table A) q= 0.18 cfs/acre One-hour Precipitation Pi= 2.68 inches Design Rainfall IOF Formula I•C1'P1/(C2+Tc)•C3 Coefficient One C,= 28.50 Coefficient Two Cr= 10.00 Coefficient Three 0,= 0.79 Determination of Average Outflow from the Basin(Calculated): Runoff Coefficient C= 0.64 Inflow Peak Runoff Op-in= 59.62 cfs Allowable Peak Outflow Rate Op-out= 2.32 cfs Ratio of Op-out/Op-in Ratio= 0.04 Determination of MAJOR Detention Volume Using FAA&Modified FAA Method 5 <-Enter Rainfall Duration Incremental Increase Value Here(e.g.5 for 5-Minutes) Rainfall Rainfall Inflow Average Outflow Storage Adjustment Average Outflow Storage Duration Intensity Volume Outflow Volume Volume Factor Outflow Volume Volume minutes inches I hr cubic feet (FAA,cos) (FAA,cf) (FAA,cf) (Modified) (Mod.cis) (Mod,of) (Mod,cf) liinPut) (output) (output) (outPul) (output) (output) (Output) (output) (output) (output) III 0 0.00 0 0.00 0 0 0.00 0.00 0 0 5 8.98 22.628 122 307 22,158 1.00 2.32 896 21,827 10 7.15 85,809 1.22 735 38,164 1.00 2.32 1,302 34,407 15 8.00 45,133 122 1,102 44,031 0.83 1.93 1,740 43,393 20 5.19 82,105 122 1,409 50,638 0.75 1.74 2,068 50,017 25 4.00 57,804 122 1,887 55,827 0.70 1.82 2,436 55228 30 4.14 02209 122 2204 00,055 0.67 1.55 2,784 89,485 35 3.77 85,192 122 2,571 83,821 0.94 149 3,132 63,060 40 3.47 69,606 122 2,930 85,868 0.83 1.45 3,480 88,128 45 322 72,823 1.22 3,308 89,322 0.81 1.42 3,820 85,000 50 3.00 75,387 122 3,873 71,683 0.80 1.39 4,175 71,161 55 2.82 77,792 122 4,041 73,752 0.59 1.37 4,524 73268 80 2.88 80,089 122 4,408 75,31 058 1.35 4,872 78,187 65 2.52 82,109 122 4,775 77,334 058 1,34 5,220 78,859 70 2,39 84,030 122 5,143 76,887 0.57 1.33 5,588 78,462 75 226 88,021 1.22 5,510 00,311 0.57 1.31 5,918 79,905 80 2.18 97,601 122 5,877 81,824 0.58 1.81 8284 51237 05 2.00 89,083 122 8,245 82,638 0.58 1.30 8,612 52,471 90 2.01 00,577 122 5,812 53,965 058 129 8,900 83,817 95 1.93 91,994 122 6,079 85,015 0.55 128 7,308 54,888 100 1.88 93,342 122 7,347 85,995 0.55 128 7,658 55,688 105 1.80 94,827 122 7,714 88,913 0.55 127 8,004 88,823 110 1.74 05,355 122 8,081 87,774 0.55 127 6,352 07,603 115 1.88 97,032 122 8,449 88,563 0.54 125 8,700 88,332 120 1.33 98,162 122 5,618 89,348 0.54 126 9,048 89,114 125 1.58 09248 122 9,183 90,085 0.54 125 9,328 89,852 130 1.54 100205 122 9,551 90,744 0.54 125 9,744 90,551 135 1.50 101,304 122 9,916 01,358 054 125 10,092 91,212 140 1.45 102230 122 10,285 01,995 0.54 124 10,440 91,840 145 1.42 103224 122 10,853 92,572 0.53 124 10,758 92,485 150 1.38 104,139 122 11,020 98,119 053 124 11,138 93,003 155 1.35 105,028 122 11,397 98,638 0.53 123 11,484 93,542 160 1.32 105,887 122 11,755 94,132 0.53 123 11,832 94,055 185 129 108,723 122 12,122 94,801 0.59 129 12,180 94,543 170 128 107,537 122 12,489 95,048 0.53 129 12,078 95,009 175 123 108,330 122 12,857 95,473 0.53 123 12,073 95,454 180 121 109,102 122 13224 95,878 0.59 122 13,224 95,678 • FAA Major Storage Volume(cubic ft.)- 95,878 Mod.FAA Major Storage Volume cubic fl.) 95,878 FAA Major Storage Volume(acrefl.)= 22011 Mod.FAA Major Storage Volume(aere4f.)= 22011 UDFCD DETENTION VOLUME ESTIMATING WORKBOOK Version 2.02,Released January 2007 UD-Delention_v2.02 main.els,Modified FAA 1/4/2008,431 PM MAJOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD • (See USDCM Volume I Runoff Chapter for description of method) Project: Aurora Milk Plant Basin ID: Main Basin Inflow and Outflow Volumes vs. Rainfall Duration Intersection of Modified and FAA Outflow Plots is et maximum detention volume 120,000 • 100,000 - - 1 80,000 e u.O .0 e, so,cloo 40,000 20,000 0 I 0 20 40 60 80 100 120 140 160 180 200 Duration(Minutes) t Inflow Volume f Modified Outflow Volume +FAA Outflow Volume • UDFCD DETENTION VOLUME ESTIMATING WORKBOOK Version 2.02,Released January 2007 UD-Detention_v2 mainsls,Modified FAA 1I4/2006,4:31 PM • r MINOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD (See USDCM Volume I Runoff Chapter for description of method) Project:Aurora Milk Plant Basin ID:Entrance (For catchments less than 160 acres only. For larger catchments,use hydrograph routing method) (Note:for catchments larger than 90 acres,CUHP hydrograph and routing are recommended) The user must fill in all of the blue cells for these sheets to function. Design Information(Input): Catchment Drainage Imperviousness I. 42.83 percent Catchment Drainage Area A= 1.6000 acres Predevelopmenl NRCS Soil Group Type= B A,B,C,or D Return Period for Detention Control T= 10 years(2,5,10,25,50,or 100) Time of Concentration of Watershed Tc= 12 minutes Allowable Unit Release Rate(See Table A) q= 0.22 ors/acre One-hour Precipitation P,= 163 inches Design Rainfall IDF Formula I=C1'P1582+Tc)•53 Coefficient One CI= 28.50 Coefficient Two C2= 10.00 Coefficient Three Cs= 0.79 Determination of Average Outflow from the Basin(Calculated): Runoff Coefficient C= 0.37 Inflow Peak Runoff Op-in= 2.43 cis Allowable Peak Outflow Rate Op-out= 0.35 cfs Ratio of OpouVOp-in Ratio= 0.14 Determination of MINOR Detention Volume Using FAA&Modified FAA Method 5 <-Enter Rainfall Duration Incremental Increase Value Here(e g.5 for 5-Minutes) Rainfall Rainfall Inflow Average Outflow Storage Adjustment Average Outflow Storage Duration Intensity Volume Outflow Volume Volume Factor Outflow Volume Volume minutes inches I hr cubic feel (FAA,cis) (FAA,cI) (FAA,cf) (Modified) (Mod.cfs) (Mod.op (Mod cp (input) (output) (output) (output) (output) (output) (output) (output) (Output) (output) • 0 0.00 0 0.00 0 0 0.00 0.00 0 0 5 5.47 971 0.19 58 918 1.00 0.85 105 898 10 4.86 1,548 0.19 119 1,492 1.59 0.85 210 1,388 15 3.85 1,948 0.19 174 1,772 0.88 001 27B 1,688 20 3.18 2,247 0.19 232 2,015 0.79 028 331 1,918 25 2.80 2,487 0.19 290 2,197 0.73 028 384 2,103 30 2.52 2,885 0.19 348 2,387 0.89 0.24 436 2249 85 2.30 2,855 0.19 406 2,449 008 023 489 2,389 40 2.11 3,002 019 484 2,538 0.84 023 541 2.481 45 1.96 4192 0.19 522 2,810 0.83 0.22 594 2,539 50 1.88 9249 0.19 580 2,659 0.82 0.22 848 2,803 55 1.72 9,355 0.19 838 2,717 0.80 021 869 2,658 80 1.62 3,452 0.19 898 2,755 0.80 021 751 2,701 a5 1.53 3,641 0.19 754 2,787 0.59 021 804 2,737 70 1.48 9,824 0.19 812 2,812 0.58 020 B56 2,788 75 1.39 8.701 0.19 870 2,831 0.58 020 909 2,792 BO 1.33 3,773 0.19 928 2,845 0.57 020 981 2,312 85 127 8,842 0.19 988 2,858 0.57 0.20 1,014 2,828 90 122 3,906 0.18 1,044 2,852 0.58 020 1,086 2,840 95 1.18 8,987 0.19 1,102 2,885 0.58 020 1,119 2,849 100 1.18 4,025 0.19 1,180 2,886 0.58 020 1,171 2,854 105 1.09 4,081 0.19 1218 2,883 005 0.19 1224 2,857 11D 1.06 4,134 0.19 1278 2,858 0.55 0.19 1278 2,858 115 1.02 4,186 0.19 1,334 2,850 0.55 0.19 1,329 2,856 120 0.99 4,233 0.19 1,392 2,841 0.55 0.19 1,881 2,852 125 0.98 4,280 0.19 1,450 2,830 0.55 0.19 1,434 2,847 130 0.94 4,325 0.19 1,508 2,917 0.54 0.19 1,485 2,839 135 0.91 4,359 0.19 1,588 2,003 0.54 0.19 1,589 2,830 140 0.89 4,411 0.19 1,824 2,757 0.54 0.19 1,591 2,820 145 0.88 4,452 0.19 1,882 2,759 0.54 0.19 1,844 2,808 150 0.84 4,491 0.19 1,740 2,751 0.64 0.19 1,596 2,795 155 0.82 4,829 0.19 1,798 2,731 0.54 0.19 1,749 2,781 190 0.80 4,588 0.19 1,858 2,710 0.54 0.19 1,801 2,785 185 0.79 4,592 0.19 1,814 2,688 0.63 0.19 1,854 2,749 170 0.77 4,898 0.19 1,972 2,585 0.53 0.19 1,908 2,731 175 0.75 4,872 0.19 2,030 2,642 0.59 0.19 1,959 2,713 150 0.74 4,705 0.19 2,088 2,517 _ 0.53 0.19 2,011 2,894 • FAA Minor Storage Volume(cubic ft.)= 2,885 Mod FAA Minor Storage Volume(cubic fl.)= 2,558 FAA Minor Storage Volume(acreA)= 00556 Mod.FAA Minor Storage Volume(acre-f.)= 0.0858 UOFCD DETENTION VOLUME ESTIMATING WORKBOOK Version 2.02,Released January 2007 UD-Detention_v2.02 entrance.als,Modified FM 1/4/2008,428 PM MINOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD • (See USDCM Volume I Runoff Chapter for description of method) Project: Aurora Milk Plant Basin ID: Enhance Inflow and Outflow Volumes vs. Rainfall Duration Intersection of Modified and FAA Outflow Plots is at maximum detention volume 5,000 i 4,500 4,000 3,500 3,000 - - e e IL V , 2.500 -. 2,000 1,500 -S 1,000 500 0 0 20 40 60 80 100 120 140 160 180 200 Duration(Minutes) f Inflow Volume —a—Modified Outflow Volume +FAA Outflow Volume • UDFCD DETENTION VOLUME ESTIMATING VVORKBOOK Version 2.02,Released January 2007 UD-Detention v2 02 entrance xls.Modified FM 1/4/2008,4'.28 PM MAJOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD • (See USDCM Volume I Runoff Chapter for description of method) Project:Aurora Milk Plant Basin ID: Entrance (For catchments less than 160 acres only. For larger catchments,use hydrograph routing method) (Note:for catchments larger than 90 acres,CUHP hydrograph and routing are recommended) The user must fill in all of the blue cells for these sheets to function. Design Information(Input): Catchment Drainage Imperviousness I.= 42.83 percent Catchment Drainage Area A= 1.6000 acres Predevelopment NRCS Soil Group Type= e A.B,C,or D Return Period for Detention Control T= 100 years(2,5,10.25,50,or 100) 'Time of Concentration of Watershed Tc= 12 minutes Allowable Unit Release Rate(See Table A) q= 0.22 cfs/acre One-hour Precipitation P,= 2.65 inches Design Rainfall IDF Formula I=C1'P1I(C2*Tc)"C3 Coeffciert One C, 28.50 Coefficient Two C2= 10.00 Coefficient Three Cs= 0.79 Determination of Average Outflow from the Basin(Calculated): Runcfr Coefficient C- 0.50 !nfow Peak R.moff Cp-in- 5.35 cfs Allowable Peak Outflow Rate Op-our= 0.35 cfs Ratio of Op-out/Op-in Ratio- 0.07 Determination of MAJOR Detention Volume Using FAA&Modified FAA Method 5 <-E-re'Rainfall Duration Incremental Increase Value here(e.g 5 for 5-Min„!es) - Rainfall Rainfall Inflow Average Outflow Storage Adjustment Average Outflow Storage Duration Intensity Volume Outflow Volume Volume Factor Outflow Volume Volume minutes inches/hr cubic feet (FAA,cfs) ;FAA.cf) (FAA,of) (Modified) (Mod,cfs) (Mod,cf) (Mod,of) .rum!) (output) (output) teuiaut: 'outh (output loutpun _(outputt output) (output) • 0 0.00 0 0.00 0 0 1.00 0.00 0 0 6 8.89 2,134 0.19 68 2,076 1.00 - 0.95 108 2,028 10 7.08 fi 9,400 0.13 112 9,288 1.00 0.35 211 9,189 i 15 5.94 4276 0.19 110 4,108 0.88 0.31 280 3,698 20 6.14 . 4,937 0.19 225 4,712 0.79 028 333 4,604 25 4.55 5,463 0.19 281 6,182 0.73 028 368 5,078 30 4.10 5,800 I 0.19 337 5,683 0.69 024 439 5,481 95 3.73 8271 { 0.19 393 5,878 0.88 023 491 5,780 40 8.43 8,596 0.19 449 8,146 0.84 023 544 6,051 45 3.19 8,681 0.19 506 8,375 0.83 D22 597 8,284 50 2.97 7,138 j 0.19 862 8,576 0.62 D22 550 8,488 _ 55 2.79 7,370 0.19 818 8,752 0.80 021 703 8,858 60 2.83 7,583 0.10 874 8,000 0.80 D21 765 8,526 85 2.49 7,779 0.19 790 7,049 0.59 0.21 808 8,071 70 2.37 7,961 0.19 787 7,175 0.58 020 861 7,100 75 228 6,131 0.19 643 7268 0.68 020 914 7,217 80 2.18 8,290 0.19 899 7,391 0.67 020 987 7,324 _ 85 2.07 8,440 0.19 968 7,485 0.57 020 1,019 7,421 90 1.99 8,582 0.19 1,011 7,670 0.58 0.20 1,072 7,510 95 1.91 8,718 0.19 1,067 7,649 0.66 020 1,125 7,591 100 1.84 8,844 0.19 1,124 7,720 0.58 0.20 1,17s 7,888 105 1.76 8,065 0.19 1,180 7,788 0.65 020 1,231 7,736 110 1.72 9,061 0.19 1288 7,848 0.55 0.18 1283 7,708 115 1.87 9,193 0.19 1,292 7,601 0.55 0.19 1,336 7,857 120 1.81 9,300 0.19 1,348 7,052 0.55 0.19 1,389 7,911 125 1.57 9,403 0.19 1,406 7,999 0.65 0.19 1,442 7,982 130 1.52 9,502 0.19 1,481 8,042 0.54 0.18 1,495 8,008 135 1.48 9,698 0.19 1,617 8,081 0.64 0.19 1,547 8,061 140 1.44 9,891 0.19 1,573 8,117 0.54 0.19 1,800 8,090 145 1.41 9,780 0.19 1,629 8,151 0.54 _ 0.19 1,853 6,127 150 1.37 9,867 0.19 1,686 8,181 0.54 0.19 1,706 6,161 155 1.34 9,951 0.13 1,742 8,209 0.54 _ 0.19 1,759 6,192 180 1.31 10,032 0.13 1,796 8,234 0.54 0,19 1,811 8,221 165 128 10,112 0.19 1,854 8,257 0.59 0.19 1,864 8,247 170 _ 125 10,189 0.19 1,910 8,278 0.63 0.19 1,917 8,272 175 1.22 10264 0.19 1,986 8,257 0.63 0.18 1,970 8294 I 180 120 10,337 0.18 2,023 8,314 0.53 0.19 2,023 8,314 I • FAA Major Storage Volume(cubic ft.)- 8,314 Mod.FAA Major Storage Volume(cubic R.)- 8,314 FAA Major Storage Volume(acre-ft.). 0.1909 Mod.FAA Major Storage Volume(acre-ft.)= 0.1808 UDFCD DETENTION VOLUME ESTIMATING WJRKB00K Version 2.02.Released January 2007 UD-Delent,or_v2 A2 entrance acs,Modified FAA ':4:2008.4 28 PV MAJOR DETENTION VOLUME BY FAA&MODIFIED FAA METHOD • (See USDCM Volume I Runoff Chapter for description of method) Project: Aurora Milk Plant Basin ID: Entrance Inflow and Outflow Volumes vs. Rainfall Duration Intersection of Modified and FAA Outflow Plots is at maximum detention volume 12,000 10,000 8,000 _.. - _ __ _ _._._ ._. . _ _ -Iu. ._.. m a y • U 6000 o I 0 4,000 2,000 0 0 20 40 60 80 100 120 140 160 180 200 Duration(Minutes) f Inflow Volume -A-Modlfled Outflow Volume +FAA Outflow Volume • UDFCD DETENTION VOLUME ESTIMATING WORKBOOK Version 2.02,Released January 2007 UDDetention v2 02 entrance xis.Modified FAA 1/4/2008,438 PM • Aurora Milk Plant 1/7/2008 Runoff Model Comparison Proposed Main Area Entrance TR-55 EFH2 FAA Full Spect FAA Full Spect Area (ac) 13.0 13.0 13.0 13.0 1.6 1.6 P2 (in) 2.1 2.1 0.95 0.95 P5(in) 2.7 2.7 1.35 1.35 P10 (in) 3.2 3.2 1.63 1.63 P25 (in) 4.0 4.0 P100 (in) 5.2 5.2 2.65 2.65 Coefficient 88 88 72.42 72.42 58 58 s (ft/ft) 0.05 0.05 0.05 0.015 Tc 0.10 0.14 0.167 0.18 C10 0.55 0.37 C100 0.64 0.5 Q5(cfs) 31.1 29.0 Q10 (CFS) 40.0 37.0 31.32 2.43 Q100 (CFS) 75.0 72.0 59.82 5.35 * coefficient type CN CN % impery % impery % impery % impery Historic Main Area Entrance TR-55 • Row TR-55 EFH2 FAA FAA Crops Pasture Pasture Pasture Table SO-1 Pasture Table SO-1 Area (ac) 13.0 13.0 13.0 13.0 13.0 P2 (in) 2.1 2.1 2.1 0.95 0.95 P5 (in) 2.7 2.7 2.7 1.35 1.35 P10 (in) 3.2 3.2 3.2 1.63 1.63 P25 (in) 4.0 4.0 4.0 P100(in) 5.2 5.2 5.2 2.65 2.65 Coefficient 78 61 61 2 2 s (ftlft) 0.05 0.05 0.05 0.05 0.05 Tc 0.10 0.19 0.12 14 14 Q5(cfs) 17.9 2.7 35.0 2.32 1.69 0.35 0.208 Q10 (CFS) 25.2 5.9 44.0 7.36 2.99 0.368 Q100 (CFS) 57.7 25.2 81.0 28.17 11.05 1.36 * coefficient type CN CN CN % impery % impery • Hello