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PROSPECT RIDGE MULTIFAMILY - PDP230015 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT
kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 October 25th, 2023 Dan Mogen City of Fort Collins Stormwater Engineering 281 N. College Ave. Fort Collins, CO 80524 RE:Prospect Ridge Multifamily Drainage Compliance Letter Dear Dan Mogen: The purpose of this drainage letter is to demonstrate that the proposed drainage design for Prospect Ridge Multifamily (the "Project") conforms to the drainage patterns set forth by the master drainage report on file with the City of Fort Collins (the "City") that was approved with the overall Rudolph Farms Subdivision (the “Master Development”). The previous drainage report, "Final Drainage Report – Rudolph Farm" was prepared by Northern Engineering in June of 2023 (“Master Drainage Report”). Excerpts from the Master Drainage Report are attached to this letter as Appendix E. The Project is located south of Prospect Ridge Drive and north of Prospect Road, on Lot 1 of Rudolph Farms (the "Site"). The Project is located in the Southwest ¼ of Section 15, Township 7 North, Range 68 West of the 6th Principal Meridian within the City of Fort Collins, State of Colorado. The Site has an area of 6.80 acres (296,274 square feet) and is currently an undeveloped parcel with an existing groundcover consisting of short grasses. The proposed project consists of six residential buildings, an office building, a pool, and associated infrastructure including site grading, utility service installation, parking, sidewalk, and landscaping. Existing Conditions – Master Plan Information The project area is within Basin 1 of the Master Development as shown in the Master Drainage Map, which is attached to this letter as Appendix A. Basin 1 has a total area of 6.80 acres and an assumed imperviousness of 80% based on its commercial zoning. Per the Master Drainage Report, flows from this basin sheet flow south to Rain Garden 1, which provides Low Impact Development (LID) for Basin 1. Detention and water quality for Basin 1 is provided by Pond 1 and Rain Garden 1 southwest of the Site. Proposed Conditions The Project has been divided into three types of basins: Sub-Basins A-F are on-site basins that flow into Rain Garden 1 via sheet flow, pans, and swales; Sub-Basin OS1 is an on-site basin that sheet flows off-site to Lake Canal; and Sub-Basin OF1 is an off-site basin that flows on-site to a swale that routes to Rain Garden 1. See Appendix B for the Proposed Drainage Map. Sub-Basin A Sub-Basin A is 1.30 acres and consists of proposed building areas, a pool area, sidewalk, and landscaping. Flows from Sub-Basin A are collected via area drains and captured by proposed storm Page 2 kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 sewer infrastructure. The proposed storm sewer infrastructure outfalls into Rain Garden 1 by proposed forebay D1 southwest of the Site, which routes to Pond 1. Sub-Basin B Sub-Basin B is 0.63 acres and consists of the northwest parking lot area, sidewalk, and landscaping. Flows from Sub-Basin B are conveyed southwest via a 4’ concrete pan, sidewalk chase, and concrete- lined swale A-A. Flows outfall into Rain Garden 1 by proposed forebay D2 southwest of the Site, which routes to Pond 1. Sub-Basin C Sub-Basin C is 1.61 acres and consists of the north parking lot area, sidewalk, and landscaping. Flows from Sub-Basin C are conveyed southwest via a 4’ concrete pan along the drive aisle and grass swale in the landscaping area. Flows outfall into Rain Garden 1 by a proposed forebay D2 southwest of the Site, which routes to Pond 1. Sub-Basin D Sub-Basin D is 2.01 acres and consists of the north access drive, building area, parking lot area, sidewalk, and landscaping. Flows from Sub-Basin D sheet flow southwest to Rain Garden 1 as well as via grass swales and concrete pans. Flows outfall into Rain Garden 1 by a proposed forebay D1 southwest of the Site, which routes to Pond 1. Sub-Basin E Sub-Basin E is 1.01 acres and consists of the south access drive, parking lot area, sidewalk, and landscaping. Flows from Sub-Basin E are conveyed south via a 4’ concrete pan, sidewalk chase, and grass swale. Flows outfall into Rain Garden 1 by a proposed forebay E south of the Site, which routes to Pond 1. Sub-Basin F Sub-Basin F is 0.15 acres and consists of a portion of the proposed access drive to the north. Flows from Sub-Basin F sheet flow east and are conveyed south via an existing grass swale provided by the Master Development. Flows outfall into Rain Garden 1 by existing forebay RG1.2 southeast of the Site, which routes to Pond 1. Sub-Basin OS1 Sub-Basin OS1 is 0.09 acres and consists of a portion of the landscaping area to the northwest. Flows from Sub-Basin OS1 sheet flow off-site northeast to the Lake Canal box culverts. The Lake Canal box culverts have a carrying capacity of 158 cfs. The Master Drainage Report accounts for basins DC1, DC2, and DC3 with a total runoff of 19.35 cfs in the major event as outlined in Appendix E – Excerpts from Master Drainage Report. Basin OS1 is proposed to add 0.11 cfs. This addition of flow is minor in comparison to the allowable 158 cfs. Sub-Basin OF1 Sub-Basin OF1 is 0.05 acres and consists of an existing landscape area and community trail west of the Site. Sub-Basin OF1 captures off-site flows draining onto the proposed Site. A grass buffer swale is proposed in the Master Development to flow to Rain Garden 1. These flows are captured onsite and routed by a concrete pan with Swale A-A via proposed forebay D2 to Rain Garden 1 and outfalls into the existing Pond 1. Page 3 kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 The Project maintains the Master Drainage Report drainage patterns with runoff from each basin directed to Rain Garden 1, the exception being runoff from OS1 (0.09 acres) that has on-site drainage flowing north off-site into Lake Canal box culverts. Per the Master Drainage Plan, detention and LID treatment are provided offsite. As such, no detention or water quality are being proposed onsite. The on-site total area directed to Master Drainage Report Pond 1 is 6.71 acres with an imperviousness of 75%. The off-site total area directed to Master Drainage Report Pond 1 is 0.50 acres with an imperviousness of 2%. The on-site total area directed off-site to Lake Canal is 0.09 acres with an imperviousness of 2%. With the proposed improvements, the Site is proposing less impervious area than anticipated in the Master Drainage Report. Rational method calculations are attached to this letter in Appendix C. Conclusion The Master Drainage Report shows the project area as Basin 1 with an assumed imperviousness of 80%. The proposed project will have an impervious value of on 74%, which is less than what was assumed. As such, the proposed project conforms with the original assumptions and conclusions of the Master Drainage plan. Please contact us with any questions or concerns. Thank You, KIMLEY-HORN AND ASSOCIATES, INC. Emily Felton, P.E. Appendices A – Master Drainage Map (Existing Conditions) B – Proposed Drainage Map C – Rational Method Calculations & Hydraulic Calculations D – FEMA Flood Map and NRCS Soil Report E – Excerpts from Master Drainage Report kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 EXHIBIT A – Master Drainage Map FES V.P.F ES DD D GAS / / / / / / / / X X X X G G / / / / / / / / / / / / / / / / / / / / / / / / X X X X X B MB M C CT C CT TC C T C util LID F ES FES D D CT V CT V FESFES D D D D DD MM / / / / / / / / X / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / G G G G X CABLEG GCTV / / / / / / / // / / / / / / / / / / / / / / / / / / / / / / // / / / / / / / U D UD UD UD UD UD UD FO S S H2O H2O H2O H2O H2O H2O H2O WV WV W S C C C W CCW E CABLE MM C W M H2O WVWV W W W W SS SS SS SS SS SS CS CONTROLIRR V.P. V.P. V.P.V.P. CABLE MM C S MMM W T H2O M 1 2 3 4 5 G 0 G 4 3 2 1 1 2 3 4 5 G 0 G 4 3 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NO P A R K I N G NO P A R K I N G / / / / / / / // / / / / / / / / / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / / SB SB SB SB 8" S S 8" S S 8" S S G G G G G G G G G G G G G G G G G G 8" W 8" W 12 " S S G G TT T T G G G 12" SS 12" SS 12 " S S TSALPOLYNDUCTILEIRON TSALPOLYNDUCTILEIRON TSALPOLYN DUCTILEIRON TSALPOLYNDUCTILEIRON TSALPOLYN DUCTILEIRON 8" W 8" W 8" W 8" W 8" W 8" W 8" W 8" W W W W TSALPOLYNDUCTILEIRON 8" W 8" W 8" W 8" W TSALPOLYNDUCTILEIRON WF FW 1 2 " S S 1 2 " S S T 8" W 8" W LOT 1 LOT 2 LOT 3 LOT 4 LOT 6 LOT 5 LOT 11 LOT 8 LOT 9 LOT 10 LOT 12 LOT 13 LOT 7 r1 r2 r5 r6 r3 r4 POND 2 (HYDRAULICALLY CONNECTED) RAIN GARDEN 2 FLAT AREA = 24,349 SQ. FT. VOLUME = 26,422 CU. FT. RAIN GARDEN 3 FLAT AREA = 16,617 SQ. FT. VOLUME = 19,079 CU. FT. RAIN GARDEN 4 FLAT AREA = 18,589 SQ. FT. VOLUME = 20,211 CU. FT. RAIN GARDEN 5 FLAT AREA = 4,164 SQ. FT. VOLUME = 4,918 CU. FT. RAIN GARDEN 1 FLAT AREA = 15,780 SQ. FT. VOLUME = 19,709 CU. CT. PRO S P E C T R I D G E D R I V E V I X E N D R I V E CAR R I A G E P A R K W A Y r7 r8 SWALE BEHIND LOTS 8 AND 9 os7 OVERTOPPING EXTENTS DURING 100-YR EVENT 16. 3 9 100-YEAR BOXELDER FLOODPLAIN SWALE SWALE BOXELDER FLOODWAY 11 1 2 6 5 4A R1 R2 9B R4 R6 R5 OS1 OS3 DC1 DC2 DC3 7 OS4 OS5 8B R3 10 13 12 3 8A 9A R7 R8 OS6 OS7 R9 R10 R11 r9 r10 r11 POND OUTLET 1 SEE SHEET ST6 POND OUTLET 2 SEE SHEET ST6 STORM DRAIN C SEE SHEET ST3 STORM DRAIN E SEE SHEET ST4 CULVERT H SEE SHEET ST7 POND CULVERT 1 SEE SHEET ST7 STORM DRAIN D SEE SHEET ST4 STORM DRAIN A SEE SHEET ST1 STORM DRAIN B SEE SHEET ST2 STORM DRAIN I SEE SHEET ST3 GREGG S SCHMIDTKE 4607 KITCHELL WAY, FORT COLLINS POUDRE SCHOOL DISTRICT PROSPECT 6-12 SCHOOLS PROSPECT ROAD IN T E R S T A T E 2 5 THOMAS J SKILLMAN 4608 KITCHELL WAY, FORT COLLINS CDOT 1012 SE FRONTAGE RD, FORT COLLINS FOX GROVE HOA 4345 FOX GROVE DR, FORT COLLINS OS2 STORM DRAIN F SEE SHEET ST5 STORM DRAIN G SEE SHEET ST5 LAKE CANAL CULVERT A SEE SHEET LC2 LAKE CANAL CULVERT B SEE SHEET LC3 LAKE CANAL CULVERT C SEE SHEET LC3 TRIC CULVERT A SEE SHEET TRIC1 TRIC CULVERT B SEE SHEET TRIC1 RAIN GARDEN 2 OVERTOPPING (150 LF WEIR) RAIN GARDEN 3 OVERTOPPING (100 LF WEIR) RAIN GARDEN 4 OVERTOPPING (123 LF WEIR) RAIN GARDEN 5 OVERTOPPING (50 LF WEIR) RAIN GARDEN 1 OVERTOPPING (242 LF WEIR) EROSION BUFFER LIMITS 1 6 . 6 7 16.6 8 1 6 . 6 7 16. 6 8 OVERTOPPING EXTENTS DURING 100-YR EVENT POND 1 POND 2 POND 3 POND 3 (HYDRAULICALLY CONNECTED) R12 R13 r12 r13 4B FG1 SWALE (BETWEEN LOT 1 AND 2) 100-YR WSEL 100-YR WSEL 100-YR WSEL 100-YR WSEL 100-YR WSEL 100-YR WSEL DRAINAGE EASEMENT POND 3 OVERTOPPING LOCATION POND 2 OVERTOPPING LOCATION 24 . 7 8 24 . 7 8 23.93 POND 4 15. 6 8 Sheet RU D O L P H F A R M Th e s e d r a w i n g s a r e in s t r u m e n t s o f s e r v i c e pr o v i d e d b y N o r t h e r n En g i n e e r i n g S e r v i c e s , I n c . an d a r e n o t t o b e u s e d f o r an y t y p e o f c o n s t r u c t i o n un l e s s s i g n e d a n d s e a l e d b y a P r o f e s s i o n a l E n g i n e e r i n th e e m p l o y o f N o r t h e r n En g i n e e r i n g S e r v i c e s , I n c . N O T F O R C O N S T R U C T I O N R E V I E W S E T of 158 PROPOSED CONTOUR PROPOSED STORM SEWER PROPOSED SWALE EXISTING CONTOUR PROPOSED CURB & GUTTER PROPERTY BOUNDARY PROPOSED INLET A DESIGN POINT FLOW ARROW DRAINAGE BASIN BOUNDARY RUNOFF SUMMARY: 1.REFER TO THE RUDOLPH FARM - FINAL DRAINAGE REPORT FOR ADDITIONAL INFORMATION. 2.ALL RAIN GARDENS WILL OVERTOP THE 100-YR EVENT INTO THEIR ADJACENT PONDS. REFER TO EROSION CONTROL SHEET FOR EROSION PROTECTION INFORMATION. 3.POND LINERS FOR POND1, POND 2, AND POND 3 ARE DESIGNED BY OTHERS. LEGEND: BASIN AREA A BASIN ID BASIN MINOR AND MAJOR C COEFFICIENTS NOTES: NORTH DR1 DR A I N A G E E X H I B I T 147 ( IN FEET ) 1 inch = ft. Feet0150150 150 300 450 BASIN TOTAL AREA (acres) Tc2 (min) Tc100 (min) C2 C100 Q2 (cfs) Q100 (cfs) 1 6.80 7.5 5.0 0.85 1.00 14.22 67.68 2 1.47 7.5 5.0 0.85 1.00 3.07 14.60 3 1.43 7.5 5.0 0.85 1.00 2.99 14.22 4A 1.43 7.2 5.0 0.85 1.00 3.05 14.18 4B 0.99 7.2 5.0 0.85 1.00 2.12 9.87 5 1.10 7.4 5.0 0.85 1.00 2.37 10.99 6 2.59 7.4 5.0 0.85 1.00 5.54 25.74 7 6.67 11.7 11.7 0.27 0.34 3.76 16.41 8A 5.74 5.0 5.0 0.95 1.00 15.53 57.07 8B 2.16 5.0 5.0 0.95 1.00 5.86 21.54 9A 10.76 5.4 5.0 0.95 1.00 29.14 107.09 9B 3.97 5.4 5.0 0.95 1.00 10.74 39.48 10 9.47 6.0 5.0 0.95 1.00 24.84 94.27 11 3.28 5.0 5.0 0.95 1.00 8.87 32.61 12 13.50 6.3 5.0 0.95 1.00 34.25 134.35 13 8.85 12.8 12.8 0.30 0.38 5.35 23.37 R1 1.31 8.4 7.3 0.81 1.00 2.55 11.54 R2 1.36 5.0 5.0 0.84 1.00 3.26 13.54 R3 1.44 13.1 12.0 0.79 0.99 2.26 10.39 R4 1.11 7.9 6.8 0.80 1.00 2.17 10.01 R5 2.83 13.9 12.9 0.78 0.98 4.30 19.40 R6 1.98 13.9 12.9 0.78 0.98 3.01 13.60 R7 0.94 5.0 5.0 0.85 1.00 2.27 9.33 R8 0.86 6.1 5.0 0.71 0.89 1.62 7.56 R9 0.40 5.0 5.0 0.80 1.00 0.91 3.98 R10 0.27 5.0 5.0 0.80 1.00 0.62 2.72 R11 0.24 5.0 5.0 0.78 0.98 0.53 2.30 R12 0.59 5.0 5.0 0.80 1.00 1.35 5.88 R13 0.54 5.0 5.0 0.80 1.00 1.22 5.34 OS1 5.16 9.0 8.4 0.24 0.30 2.85 12.98 OS2 1.33 5.0 5.0 0.86 1.00 3.27 13.27 OS3 3.76 11.2 11.2 0.20 0.25 1.60 6.97 OS4 5.55 8.9 8.3 0.25 0.31 3.26 14.54 OS5 3.10 9.4 8.9 0.20 0.25 1.43 6.36 OS6 1.23 5.4 5.2 0.20 0.25 0.70 3.06 OS7 0.42 5.0 5.0 0.20 0.25 0.24 1.04 DC1 2.02 5.2 5.0 0.20 0.25 1.15 5.03 DC2 2.21 5.2 5.0 0.20 0.25 1.26 5.50 DC3 3.54 5.2 5.0 0.20 0.25 2.02 8.82 FG1 0.27 5.0 5.0 0.78 0.98 0.60 2.63 Pond Summary Pond ID WQCV (cu. ft.)WQCV WSEL 100-YR Volume (cu. ft.)100-YR WSEL Max Release Rate (cfs) 1 10,241 4904.41 201,893 4908.43 14.68 2 22,638 4911.25 618,699 4915.66 7 3 N/A N/A 197,769 4921.97 7 4 2,100 4911.46 31,231 4913.07 3.69 PROPOSED SITE RAIN GARDEN 1 OVERTOPPING (242 LF WEIR) kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 EXHIBIT B – Proposed Drainage Map TH I S D O C U M E N T , T O G E T H E R W I T H T H E C O N C E P T S A N D D E S I G N S P R E S E N T E D H E R E I N , A S A N I N S T R U M E N T O F S E R V I C E , I S I N T E N D E D O N L Y F O R T H E S P E C I F I C P U R P O S E A N D C L I E N T F O R W H I C H I T W A S P R E P A R E D . R E U S E O F A N D I M P R O P E R R E L I A N C E O N T H I S D O C U M E N T W I T H O U T W R I T T E N A U T H O R I Z A T I O N A N D A D A P T A T I O N B Y K I M L E Y - H O R N A N D A S S O C I A T E S , I N C . S H A L L B E W I T H O U T L I A B I L I T Y T O K I M L E Y - H O R N A N D A S S O C I A T E S , I N C . R Know what's below. Call before you dig. DESIGNED BY: DRAWN BY: CHECKED BY: DATE: NO . RE V I S I O N BY DA T E © 2 0 2 3 K I M L E Y - H O R N A N D A S S O C I A T E S , I N C . 38 0 1 A U T O M A T I O N W A Y , S U I T E 2 1 0 FO R T C O L L I N S , C O L O R A D O 8 0 5 2 5 ( 9 7 0 ) 8 2 2 - 7 9 1 1 FOR REVIEW ONLY NOT FOR Kimley-Horn and Associates, Inc. CONSTRUCTION K: \ N C O _ C i v i l \ 1 9 6 3 9 5 0 0 3 _ P r o s p e c t R i d g e M u l t i f a m i l y \ C A D D \ P l a n S h e e t s \ C - D M A P . d w g PROJECT NO. SHEET 10/25/2023 AGR MH HPC OF 15 196395003 PR O S P E C T R I D G E M U L T I F A M I L Y PR E L I M I N A R Y C O N S T R U C T I O N P L A N S NORTH XXXX XXXX XXXX XXXX PROPERTY LINE EASEMENT LINE SETBACK/BUILD-TO LINE PROPOSED ASPHALT PAVEMENT PROPOSED LANDSCAPE AREA CONCRETE PAVEMENT/SIDEWALK PROPOSED MAJOR CONTOUR PROPOSED MINOR CONTOUR EXISTING MAJOR CONTOUR EXISTING MINOR CONTOUR DRAINAGE BASIN BOUNDARY PROPOSED FLOW ARROW OVERFLOW PATH ARROW A = BASIN ID B = BASIN AREA (AC) C = BASIN IMPERVIOUSNESS DESIGN POINT 15 PR O P O S E D D R A I N A G E P L A N NORTH LEGEND SWALE CROSS SECTION A-A N.T.S. (SWALE WIDTH VARIES) TS U D U D U D U D U D U D U D UD U D U D UD UD UD UD UD UD TC T VAULT F.O. C FO CT V T T T T T T VAN VAN 4 9 1 6 49 1 6 49 1 5 4913 49 1 3 49 1 4 4 9 1 5 491 1 4912 4913 49 1 4 4 9 1 6 4 9 1 7 4 9 1 8 4 9 1 8 49 1 5 49 1 1 4911 491 2 49 1 2 4 9 1 2 4 9 1 3 49 1 4 491 6 49 1 7 49 1 5 4 9 1 5 4915 4 9 1 5 4 9 1 6 4 9 1 7 4 9 1 8 4 9 1 9 4 9 1 9 49 1 9 491 7 49 1 7 4918 491 5 4914 491 6 49 1 7 4 9 1 5 4 9 1 5 491 3 4 9 1 4 4 9 1 6 49 1 6 49 1 5 4913 49 1 3 49 1 4 4 9 1 5 491 1 4912 4913 49 1 4 4 9 1 6 4 9 1 7 4 9 1 8 4 9 1 8 49 1 5 49 1 1 4911 491 2 49 1 2 4 9 1 2 4 9 1 3 49 1 4 491 6 49 1 7 49 1 5 4 9 1 5 4915 4 9 1 5 4 9 1 6 4 9 1 7 4 9 1 8 4 9 1 9 4 9 1 9 49 1 9 491 7 49 1 7 4918 491 5 4914 491 6 49 1 7 4 9 1 5 4 9 1 5 491 3 4 9 1 4 49 1 0 49 1 5 49 1 1 49 1 2 49 1 3 49 1 4 49 1 6 49 1 6 4917 49 1 7 491 5 4912 4913 491 4 49 1 6 49 1 7 4 9 1 5 4911 4912 4 9 1 3 4 9 1 4 4916 4917 4917 4 9 0 5 4 9 1 0 4 9 0 4 4 9 0 6 4 9 0 7 4 9 0 8 49 0 8 4 9 0 8 4 9 0 9 4900 4896 4897 4898 4899 4901 4902 4903 4 9 1 6 4 9 1 7 4 9 1 6 4917 491 8 491 9 491 7 491 8 49 1 9 4 9 1 8 4 9 1 7 4 9 1 8 49 1 9 4917 BUILDING 4 BUILDING 6 BUILDING 3 BUILDING 2 BUILDING 5 BUILDING 1 SOUTH LEASING PROPOSED SITE DRAINAGE TO RAIN GARDEN WITH FOREBAY E EXISTING RUDOLPH FARM RAIN GARDEN 1 (LID TREATMENT PROVIDED WITH MASTER DRAINAGE PLAN) TRACT E RUDOLPH FARM POND 1 LOT 2 1.46 AC. T R A C T E TI M N A T H R E S E R V O I R I N L E T C A N A L FOREBAY D2 PROPOSED 1' CURB CUT 2' SIDEWALK CHASE PROPOSED STORM LINE - SEE UTILITY PLANS 9. 0 ' E X . U T I L . E S M T 10 . 0 ' E X . D R N G E S M T 4.0' CO N C . P A N 2.0 ' C O N C . P A N PROPOSED SWALE 2' SIDEWALK CHASE 4. 0 ' C O N C . P A N 20' UTIL. ESMT. 24' UTIL. & EMER. ACCESS ESMT 30' UT I L . ESMT. 2 6 ' E M E R . A C C E S S E S M T 30' U T I L . ESM T . PROPOSED AREA DRAIN (TYP.) PROPOSED 2' CURB CUT EXISTING FOREBAY RG1.2 LOT 1 6.80 AC. PROPOSED CONCRETE-LINED SWALE SEE CROSS SECTION A-A FOREBAY D1 PR O S P E C T R I D G E D R . L A K E C A N A L PROSPECT RIDGE DR. LOT 4 2.38 AC. BUILDING 1 NORTH 4.0' C O N C R E T E - L I N E D S W A L E PROPOSED SIDEWALK PROPERTY LINE EXISTING S L O P E S ~ 3 % MAX CROSS SLOPE 2% 4' CONCRETE PAN kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 EXHIBIT C – Rational Method & Hydraulic Calculations TIME 2 YR 10 YR 100 YR 5 2.85 4.87 9.95 6 2.67 4.56 9.31 7 2.52 4.31 8.80 8 2.40 4.10 8.38 9 2.30 3.93 8.03 10 2.21 3.78 7.72 11 2.13 3.63 7.42 12 2.05 3.50 7.16 13 1.98 3.39 6.92 14 1.92 3.29 6.71 15 1.87 3.19 6.52 20 1.61 2.74 5.60 25 1.43 2.44 4.98 30 1.30 2.21 4.52 40 1.07 1.83 3.74 50 0.92 1.58 3.23 60 0.82 1.40 2.86 120 0.49 0.86 1.84 Note: Time Intensity Frequency Tabulation Intensity values from the City of Fort Collins Intensity-Duration-Frequency Tables; Chapter 5, Section 3.4 of the Fort Collins Stormwater Criteria Manual, 2018 Edition. RAINFALL INTENSITY K:\NCO_Civil\196395003_Prospect Ridge Multifamily\Project Files\Eng\Drainage\Calcs\PR CIA Calcs.xlsx PROJECT NAME: Prospect Ridge Multifamily 10/25/2023 PROJECT NUMBER: 196395003 CALCULATED BY: MH CHECKED BY:HPC SOIL: GROUP B Lawns, Sandy Soil Rooftop Asphalt, Concrete LAND USE:AREA AREA AREA 2-YEAR COEFF.0.10 0.95 0.95 100-YEAR COEFF.0.10 0.95 0.95 IMPERVIOUS %2%90%100% Lawns, Sandy Soil Rooftop Asphalt, Concrete TOTAL DESIGN DESIGN AREA AREA AREA AREA BASIN POINT (AC)(AC)(AC)(AC)C(2)C(100)Imp % A A 0.36 0.82 0.12 1.30 0.72 0.89 67% B B 0.18 0.00 0.44 0.63 0.70 0.88 71% C C 0.18 0.00 1.43 1.61 0.86 1.07 89% D D 0.53 0.83 0.65 2.01 0.73 0.91 70% E E 0.12 0.00 0.90 1.01 0.85 1.07 89% F F 0.15 0.00 0.00 0.15 0.10 0.13 2% 1.51 1.65 3.54 6.71 0.76 0.95 75% 23%25%53% OS1 OS1 0.09 0.00 0.00 0.09 0.10 0.13 2% 0.09 0.00 0.00 0.09 0.10 0.13 2% 100%0%0% OF1 OF1 0.50 0.00 0.00 0.50 0.10 0.13 2% 0.50 0.00 0.00 0.50 0.10 0.13 2% 100%0%0% TOTAL DISTURBED AREA 1.60 1.65 3.54 6.80 74% TOTAL TO RAIN GARDEN 1 2.02 1.65 3.54 7.21 70% TOTAL TO LAKE CANAL 0.09 0.00 0.00 0.09 2% Notes: 1. Imperviousness, I, values per UDFCD Criteria Manual Volume 1, Table 6-3 2. Runoff Coefficient values are from the City of Fort Collins Runoff Coefficient Tables 3.2-2 and 3.2-3; Chapter 5, Section 3.2 of the Fort Collins Stormwater Criteria Manual, 2018 Edition. Frequency adjustment factor has been applied to composite C values per Table 3.2-3. BASIN SUBTOTAL BASIN SUBTOTAL On-Site Basins Flowing On-site Off-Site Basins Flowing On-Site RUNOFF COEFFICIENTS - IMPERVIOUS CALCULATION On-Site Basins Flowing Off-site BASIN SUBTOTAL K:\NCO_Civil\196395003_Prospect Ridge Multifamily\Project Files\Eng\Drainage\Calcs\PR CIA Calcs.xlsx Prospect Ridge Multifamily DATE: 10/25/2023 196395003 MH HPC FINAL Tc DESIGN AREA C2 LENGTH SLOPE Ti LENGTH SLOPE R VEL Tt COMP.TOTAL TOTAL TOTAL Tc BASIN Ac Ft %Min.Ft.%fps Min.tc LENGTH SLOPE IMP.Min.Min. A 1.30 0.72 245 2.0%8.9 295 1.0%0.195 3.9 1.3 10.2 540 1.5%67%13.0 10.2 B 0.63 0.70 92 2.1%5.6 184 0.6%0.195 2.9 1.1 6.7 275 1.1%71%11.5 6.7 C 1.61 0.86 159 2.5%4.2 85 0.9%0.195 3.6 0.4 4.6 244 1.9%89%11.4 5.0 D 2.01 0.73 72 3.8%3.8 187 3.4%0.195 7.1 0.4 4.2 258 3.5%70%11.4 5.0 E 1.01 0.85 59 3.8%2.3 296 1.9%0.195 5.3 0.9 3.2 355 2.2%89%12.0 5.0 F 0.15 0.10 16 10.1%3.5 290 2.0%0.195 5.5 0.9 4.3 306 2.4%2%11.7 5.0 OS1 0.09 0.10 8 6.6%2.8 0 0.0%0.195 0.0 0.0 2.8 8 6.6%0%10.0 5.0 OF1 0.50 0.10 73 1.9%13.0 630 1.0%0.195 3.9 2.7 15.7 702 1.1%2%13.9 13.9 On-Site Basins Flowing Off-Site CHECKED BY: On-Site Basins Off-Site Basins Flowing On-Site 2-Year Time of Concentration Tc CHECK (URBANIZED BASINS) PROJECT NAME: PROJECT NUMBER: DATA INITIAL TIME (Ti) TRAVEL TIME (Tt) SUB-BASIN CALCULATED BY: K:\NCO_Civil\196395003_Prospect Ridge Multifamily\Project Files\Eng\Drainage\Calcs\PR CIA Calcs.xlsx Prospect Ridge Multifamily DATE: 10/25/2023 196395003 MH HPC FINAL Tc DESIGN AREA C100 LENGTH SLOPE Ti LENGTH SLOPE R VEL Tt COMP.TOTAL TOTAL TOTAL Tc BASIN Ac Ft %Min.Ft.%fps Min.tc LENGTH SLOPE IMP.Min.Min. A 1.30 0.89 245 2.0%4.8 295 1.0%0.195 3.9 1.3 6.1 540 1.5%67%13.0 6.1 B 0.63 0.88 92 2.1%3.2 184 0.6%0.195 2.9 1.1 4.2 275 1.1%71%11.5 5.0 C 1.61 1.07 159 2.5%0.5 85 0.9%0.195 3.6 0.4 0.9 244 1.9%89%11.4 5.0 D 2.01 0.91 72 3.8%1.9 187 3.4%0.195 7.1 0.4 2.4 258 3.5%70%11.4 5.0 E 1.01 1.07 59 3.8%0.3 296 1.9%0.195 5.3 0.9 1.2 355 2.2%89%12.0 5.0 F 0.15 0.13 16 10.1%3.4 290 2.0%0.195 5.5 0.9 4.3 306 2.4%2%11.7 5.0 OS1 0.09 0.13 8 6.6%2.8 0 0.0%0.195 0.0 0.0 2.8 8 6.6%0%10.0 5.0 OF1 0.50 0.13 73 1.9%12.6 630 1.0%0.195 3.9 2.7 15.3 702 1.1%2%13.9 13.9 CHECKED BY: 100-Year Time of Concentration PROJECT NAME: PROJECT NUMBER: CALCULATED BY: On-Site Basins Off-Site Basins Flowing On-Site SUB-BASIN INITIAL TRAVEL TIME Tc CHECK DATA TIME (Ti)(Tt)(URBANIZED BASINS) On-Site Basins Flowing Off-Site K:\NCO_Civil\196395003_Prospect Ridge Multifamily\Project Files\Eng\Drainage\Calcs\PR CIA Calcs.xlsx DATE: 10/25/2023 Prospect Ridge Multifamily 196395003 MH P1 (1-Hour Rainfall) =0.82 HPC REMARKS DESIGN POINT AREA (AC) RUNOFF COEFF tc (min) C*A(ac) I (in/hr) Q (cfs) A 1.30 0.72 10.22 0.93 2.20 2.05 Flows south to Rain Garden 1 via storm sewer B 0.63 0.70 6.68 0.44 2.56 1.12 Flows southwest to Rain Garden 1 via Forebay D2 C 1.61 0.86 5.00 1.38 2.78 3.84 Flows southwest to Rain Garden 1 via Forebay D2 D 2.01 0.73 5.00 1.46 2.78 4.06 Flows southwest to Rain Garden 1 via Forebay D1 E 1.01 0.85 5.00 0.86 2.78 2.40 Flows south to Rain Garden 1 via Forebay E F 0.15 0.10 5.00 0.02 2.78 0.04 Flows south to Rain Garden 1 via existing Forebay RG 1.2 OS1 0.09 0.10 5.00 0.01 2.78 0.03 Flows North to Lake Canal OF1 0.50 0.10 13.90 0.05 1.93 0.10 Flows south to Rain Garden 1 via Forebay D2 On-Site Basins Off-Site Basins Flowing On-Site E F C D OF1 On-Site Basins Flowing Off-Site OS1 STORM DRAINAGE DESIGN - RATIONAL METHOD 2 YEAR EVENT PROJECT NAME: PROJECT NUMBER: CALCULATED BY: CHECKED BY: DESGIN BASIN A B K:\NCO_Civil\196395003_Prospect Ridge Multifamily\Project Files\Eng\Drainage\Calcs\PR CIA Calcs.xlsx DATE: 10/25/2023 Prospect Ridge Multifamily 196395003 MH P1 (1-Hour Rainfall) =2.86 HPC REMARKS DESIGN POINT AREA (AC) RUNOFF COEFF tc (min) C*A(ac) I (in/hr) Q (cfs) A 1.30 0.89 10.22 1.16 7.67 8.93 Flows south to Rain Garden 1 via storm sewer B 0.63 0.88 6.68 0.55 8.92 4.89 Flows southwest to Rain Garden 1 via Forebay D2 C 1.61 1.07 5.00 1.72 9.70 16.72 Flows southwest to Rain Garden 1 via Forebay D2 D 2.01 0.91 5.00 1.83 9.70 17.71 Flows southwest to Rain Garden 1 via Forebay D1 E 1.01 1.07 5.00 1.08 9.70 10.48 Flows south to Rain Garden 1 via Forebay E F 0.15 0.13 5.00 0.02 9.70 0.18 Flows south to Rain Garden 1 via existing Forebay RG 1.2 OS1 0.09 0.13 5.00 0.01 9.70 0.11 Flows North to Lake Canal OF1 0.50 0.13 13.90 0.06 6.73 0.42 Flows south to Rain Garden 1 via Forebay D2 CHECKED BY: CALCULATED BY: STORM DRAINAGE DESIGN - RATIONAL METHOD 100 YEAR EVENT PROJECT NAME: PROJECT NUMBER: On-Site Basins Off-Site Basins Flowing On-Site A B C D F E OF1 On-Site Basins Flowing Off-Site OS1 DESIGN BASIN K:\NCO_Civil\196395003_Prospect Ridge Multifamily\Project Files\Eng\Drainage\Calcs\PR CIA Calcs.xlsx PROJECT NAME:Prospect Ridge Multifamily DATE: 10/25/2023 PROJECT NUMBER: 196395003 CALCULATED BY:MH CHECKED BY: HPC IMPERVIOUSNESS %Q2 Q100 A A 1.30 67%2.05 8.93 B B 0.63 71%1.12 4.89 C C 1.61 89%3.84 16.72 D D 2.01 70%4.06 17.71 E E 1.01 89%2.40 10.48 F F 0.15 2%0.04 0.18 6.71 75%13.51 58.92 OS1 OS1 0.09 2%0.03 0.11 0.09 2%0.03 0.11 OF1 OF1 0.50 2%0.10 0.42 0.50 2%0.10 0.42 Forebay D1 A, D 3.31 69%6.11 26.64 Forebay D2 B, C, OF1 2.74 69%5.05 22.03 Forebay E E 1.01 89%2.40 10.48 Existing Forebay RG1.2 F 0.15 0.02 0.04 0.18 7.21 74%13.61 59.34 Sheet Flow OS1 0.09 2%0.03 0.11 0.09 2%0.03 0.11 TOTAL Off-Site Basins Flowing On-Site On-Site Basins Flowing On-Site DESIGN POINT On-Site Basins Flowing Off-Site TOTAL RATIONAL CALCULATIONS SUMMARY TRIBUTARY BASINS TRIBUTARY AREA (AC) PEAK FLOWS (CFS) TOTAL TOTAL Routed Flows - to Pond 1 Routed Flows - to Lake Canal Box Culverts TOTAL K:\NCO_Civil\196395003_Prospect Ridge Multifamily\Project Files\Eng\Drainage\Calcs\PR CIA Calcs.xlsx Cross Section for Forebay D1 Project Description Manning FormulaFriction Method DischargeSolve For Input Data 0.013Roughness Coefficient %2.000Channel Slope in6.0Normal Depth ft0.30Bottom Width cfs0.57Discharge Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/18/2023 FlowMaster [10.03.00.03] Bentley Systems, Inc. Haestad Methods Solution CenterHydraulic Calcs.fm8 > 0.53 cfs = 2% of 100-year flow from Sub-Basin A + D Cross Section for Forebay D2 Project Description Manning FormulaFriction Method DischargeSolve For Input Data 0.013Roughness Coefficient %2.500Channel Slope in6.0Normal Depth ft0.25Bottom Width cfs0.49Discharge Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/18/2023 FlowMaster [10.03.00.03] Bentley Systems, Inc. Haestad Methods Solution CenterHydraulic Calcs.fm8 > 0.47 cfs = 2% of 100-year flow from Sub-Basins B, C, & OF1 Cross Section for Forebay E Project Description Manning FormulaFriction Method DischargeSolve For Input Data 0.013Roughness Coefficient %2.000Channel Slope in6.0Normal Depth ft0.25Bottom Width cfs0.44Discharge Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 10/18/2023 FlowMaster [10.03.00.03] Bentley Systems, Inc. Haestad Methods Solution CenterHydraulic Calcs.fm8 > 0.21 cfs = 2% of 100-year flow from Sub-Basin E kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 EXHIBIT D – FEMA Flood Map & NRCS Soil Report National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 9/25/2023 at 6:10 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. 1:6,000 105°0'17"W 40°34'17"N 104°59'40"W 40°33'50"N Basemap Imagery Source: USGS National Map 2023 United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Larimer County Area, ColoradoNatural Resources Conservation Service October 17, 2023 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Larimer County Area, Colorado......................................................................13 24—Connerton-Barnum complex, 0 to 3 percent slopes............................13 35—Fort Collins loam, 0 to 3 percent slopes..............................................14 40—Garrett loam, 0 to 1 percent slopes.....................................................16 References............................................................................................................18 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 44 9 0 6 8 0 44 9 0 7 3 0 44 9 0 7 8 0 44 9 0 8 3 0 44 9 0 8 8 0 44 9 0 9 3 0 44 9 0 9 8 0 44 9 1 0 3 0 44 9 0 6 8 0 44 9 0 7 3 0 44 9 0 7 8 0 44 9 0 8 3 0 44 9 0 8 8 0 44 9 0 9 3 0 44 9 0 9 8 0 44 9 1 0 3 0 499900 499950 500000 500050 500100 500150 500200 499900 499950 500000 500050 500100 500150 500200 40° 34' 13'' N 10 5 ° 0 ' 4 ' ' W 40° 34' 13'' N 10 4 ° 5 9 ' 5 1 ' ' W 40° 34' 0'' N 10 5 ° 0 ' 4 ' ' W 40° 34' 0'' N 10 4 ° 5 9 ' 5 1 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 50 100 200 300 Feet 0 25 50 100 150 Meters Map Scale: 1:1,970 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Survey Area Data: Version 18, Aug 24, 2023 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 2, 2021—Aug 25, 2021 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 24 Connerton-Barnum complex, 0 to 3 percent slopes 0.0 0.5% 35 Fort Collins loam, 0 to 3 percent slopes 1.8 25.2% 40 Garrett loam, 0 to 1 percent slopes 5.4 74.4% Totals for Area of Interest 7.2 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or Custom Soil Resource Report 11 landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Larimer County Area, Colorado 24—Connerton-Barnum complex, 0 to 3 percent slopes Map Unit Setting National map unit symbol: jpvw Elevation: 5,000 to 6,000 feet Mean annual precipitation: 15 to 18 inches Mean annual air temperature: 47 to 49 degrees F Frost-free period: 115 to 130 days Farmland classification: Prime farmland if irrigated Map Unit Composition Connerton and similar soils:50 percent Barnum and similar soils:40 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Connerton Setting Landform:Fans, flood plains, stream terraces Landform position (three-dimensional):Base slope, tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Mixed alluvium derived from sandstone and shale Typical profile H1 - 0 to 8 inches: fine sandy loam H2 - 8 to 60 inches: loam Properties and qualities Slope:1 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately high (0.20 to 0.60 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water supply, 0 to 60 inches: Moderate (about 8.8 inches) Interpretive groups Land capability classification (irrigated): 2e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Ecological site: R049XB202CO - Loamy Foothill Hydric soil rating: No Description of Barnum Setting Landform:Fans, terraces, valleys Custom Soil Resource Report 13 Landform position (three-dimensional):Base slope, tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Mixed alluvium derived from sandstone and shale Typical profile H1 - 0 to 10 inches: loam H2 - 10 to 60 inches: stratified loamy fine sand to clay loam Properties and qualities Slope:0 to 1 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.60 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:OccasionalNone Frequency of ponding:None Calcium carbonate, maximum content:5 percent Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water supply, 0 to 60 inches: High (about 9.7 inches) Interpretive groups Land capability classification (irrigated): 2e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Ecological site: R049XY036CO - Overflow Hydric soil rating: No Minor Components Garrett Percent of map unit:5 percent Hydric soil rating: No Otero Percent of map unit:5 percent Hydric soil rating: No 35—Fort Collins loam, 0 to 3 percent slopes Map Unit Setting National map unit symbol: 2tlnc Elevation: 4,020 to 6,730 feet Mean annual precipitation: 14 to 16 inches Mean annual air temperature: 46 to 48 degrees F Frost-free period: 135 to 160 days Farmland classification: Prime farmland if irrigated Custom Soil Resource Report 14 Map Unit Composition Fort collins and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Fort Collins Setting Landform:Interfluves, stream terraces Landform position (three-dimensional):Interfluve, tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Pleistocene or older alluvium and/or eolian deposits Typical profile Ap - 0 to 4 inches: loam Bt1 - 4 to 9 inches: clay loam Bt2 - 9 to 16 inches: clay loam Bk1 - 16 to 29 inches: loam Bk2 - 29 to 80 inches: loam Properties and qualities Slope:0 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.20 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:12 percent Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm) Available water supply, 0 to 60 inches: High (about 9.1 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: C Ecological site: R067BY002CO - Loamy Plains Hydric soil rating: No Minor Components Nunn Percent of map unit:10 percent Landform:Stream terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY002CO - Loamy Plains Hydric soil rating: No Vona Percent of map unit:5 percent Landform:Interfluves Custom Soil Resource Report 15 Landform position (three-dimensional):Interfluve, side slope Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY024CO - Sandy Plains Hydric soil rating: No 40—Garrett loam, 0 to 1 percent slopes Map Unit Setting National map unit symbol: jpwg Elevation: 5,200 to 6,000 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Prime farmland if irrigated Map Unit Composition Garrett and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Garrett Setting Landform:Fans, terraces Landform position (three-dimensional):Base slope, tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Alluvium derived from sandstone and shale Typical profile H1 - 0 to 8 inches: loam H2 - 8 to 39 inches: sandy clay loam H3 - 39 to 60 inches: sandy loam Properties and qualities Slope:0 to 1 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.60 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:10 percent Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water supply, 0 to 60 inches: Moderate (about 8.3 inches) Interpretive groups Land capability classification (irrigated): 2w Custom Soil Resource Report 16 Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Ecological site: R049XY036CO - Overflow Hydric soil rating: No Minor Components Harlan Percent of map unit:6 percent Ecological site:R067BY002CO - Loamy Plains Hydric soil rating: No Barnum Percent of map unit:5 percent Ecological site:R067BY036CO - Overflow Hydric soil rating: No Connerton Percent of map unit:4 percent Ecological site:R067BY002CO - Loamy Plains Hydric soil rating: No Custom Soil Resource Report 17 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 18 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 19 kimley-horn.com 3801 Automation Way, Suite 210, Fort Collins, CO 80525 970 986 6807 EXHIBIT E – Excerpts From Master Report FINAL DRAINAGE REPORT RUDOLPH FARM FORT COLLINS, COLORADO JUNE 22, 2023 NORTHERNENGINEERING.COM 970.221.4158 FORT COLLINS GREELEY NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: RUDOLPH FARM FORT COLLINS | GREELEY 8 | 17 that drains to the Lake Canal. A Stormwater Discharge Agreement with Lake Canal and New Cache will be provided at final recordation. All drainage facilities proposed with the Rudolph Farm project are designed in accordance with criteria outlined in the FCSCM and Timnath Stormwater Master Plan. As stated in Section I.C.1 above, the subject property has a small portion of regulatory floodplain restrictions and development code at the northeast corner of the site. However, no development is proposed to take place in this area. Rudolph Farm will be providing full standard water quality and LID for all future developments. Future developments cannot exceed the assumed percent impervious values. See Section I.VA of this report for additional clarification. F. FLOODPLAIN REGULATIONS COMPLIANCE No occupied structures are being proposed with the Rudolph Farm project. G. MODIFICATIONS OF CRITERIA Rudolph Farm is seeking a modifications to criteria. Rudolph Farm is seeking to utilize a discharge rate of 7 cfs for the northern portion of the site which follows the Timnath Master Plan. This discharge rate is below the historic 2-year rate as shown in Appendix A. This will improve downstream function of the TRIC and alleviate some of the overtopping. An updated exhibit and memo “TRIC Analysis for Rudolph Farm Development” by Galloway showing the reduction to downstream overtopping spills has been included at the start of Appendix C. Confirmation and agreement from the Town of Timnath that Rudolph Farm is not adversely impacting the TRIC downstream from the site is required prior to approval/construction. The Town of Timnath will be signing the development plans to indicate their approval. DRAINAGE FACILITY DESIGN A. GENERAL CONCEPT The main objectives of Rudolph Farm are to provide detention, water quality, and LID for the proposed infrastructure package as well as all future developments. Excluding the TRIC and Lake Canal, there are minor off-site flows draining onto the existing property from Prospect Road. These flows are being routed to Pond 1 for standard water quality and detention. A list of tables and figures used within this report can be found in the Table of Contents at the front of the document. The tables and figures are located within the sections to which the content best applies. Rudolph Farm project comprises forty (40) drainage basins, designated as Basins 1-13, R1-R13, OS1-OS7, FG1, and DC1-DC3. The drainage patterns for each basin are described below. Basin 1 Basin 1 is at the southwest corner of the project site. It is zoned as commercial and thus has an assumed percent impervious of 80%. Detention for Basin 1 is provided in Pond 1. Rain Garden 1 provides LID for Basin 1. Basin 2 NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: RUDOLPH FARM FORT COLLINS | GREELEY 15 | 17 Additionally, there is an LID exhibit in Appendix C that shows where all the rain gardens are located. Table 2 - WQCV AND LID SUMMARY Pond 1 provides standard water quality for Basins 5, 6, OS1, and OS2. Pond 1 provides detention for Basins 1-6, R1, R2, OS1, and OS2. Pond 1 has a maximum release rate of 14.68 cfs, which is the historic 2-year runoff (Basin EX1). Pond 2 provides standard water quality for Basins 8B, 9B, 11, R6, R7, R8, R9, R10, R11, OS4, OS5, OS6, and OS7. Pond 2 provides detention for Basins 8-11, R3-R11, OS4, OS5, OS6, and OS7. Pond 2 has a maximum release rate of 7.00 cfs as described in Section II.A of this report. Pond 3 provides detention for Basins 12 and 13. Pond 3 does not have standard water quality because Basins 12 and 13 are both receiving 100% WQCV via LID treatments. Pond 3 discharges into Pond 2. In order to minimize the footprint of Pond 2, Pond 3 has a maximum release rate of 7.00 cfs which matches the maximum release rate of Pond 2. A fourth pond was sized for Lot 7 in the SWMM analysis as shown in Appendix B.3. Pond 4 has a maximum release rate of 3.69 cfs, which is the historic 2-year rate (Basin EX2). Interim Pond 4 is getting constructed with this development. When Lot 7 is developed it must follow all of the criteria set forth in FCSCM for the ultimate Pond 4 configuration using the maximum release rate set in this report. At the time of the ultimate configuration of Pond 4, the developer/engineer of Lot 7 will need to re-register the pond with the state based on the modifactions. Pond ID Max Release Rate (cfs) Max Volume (1000 cu. ft.) 1 14.68 201.893 2 7.00 618.699 3 7.00 197.769 4 3.69 31.231 Table 3 - Pond Summary Ponds 1, 2, and 3 will all be used as combination retention ponds, irrigation ponds, and detention ponds. Hines, INC. is responsible for designing the retention ponds and irrigation ponds and a memo has been supplied describing how these retention/irrigation ponds interact below the detention ponds. Essentially, the retention/irrigation ponds working surface elevation is the Design Point (Basin Id)1 Total Area (ac) Treatment Method Area Treated (ac) Percent Impervious (%) Area of Impervious (ac)2 Required Standard Water Quality (cu. ft.) Required LID (cu. ft.) Provided LID (cu. ft.) RG1 14.57 Rain Garden 14.57 80% 11.66 N/A 13,892 19,709 Standard WQ Pond 1 11.55 Standard WQ 11.55 49% 5.66 10,241 N/A RG 2 17.94 Rain Garden 17.94 89% 15.97 N/A 20,481 26,422 RG 3 13.41 Rain Garden 13.41 86% 11.53 N/A 14,389 19,079 Standard WQ Pond 2 24.54 Standard WQ 24.54 52% 12.76 22,638 N/A RG 4 13.50 Rain Garden 13.50 90% 12.15 N/A 15,740 20,211 RG 5 8.85 Rain Garden 8.85 30% 2.66 N/A 3,893 4,918 Percent of Impervious Area Standard WQ Totals 36.09 Standard WQ 36.09 N/A 18.42 25% Rain Garden Totals 68.27 Rain Garden 68.27 N/A 53.96 75% Standard Water Quality and LID Summary Table NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: RUDOLPH FARM FORT COLLINS | GREELEY 16 | 17 invert of the detention pond. There is going to be a series of pumps and floats that pull water from surrounding wells that will maintain this working surface elevation during irrigation operations and account for evaporation losses for the retention pond. At no point shall stormwater ever be used for irrigation or retention purposes. Refer to Appendix B.3 for the memo from Hines Inc. Standard water quality depths were calculated and input as initial depth within the SWMM model so the ponds would be adequately sized for both detention and water quality. Additionally, the rating curves for each pond incorporated the 40-hour drain time for the WQCV. For additional insight into how these volumes were calculated, please refer to the SWMM results found in Appendix B. Lot 7 will be developed to an interim condition. The interim condition includes Pond 4 which will provide detention and standard water quality. Once Lot 7 developes to it’s ultimate condition it will need to reevaluate Pond 4 as well as include LID treatment for onsite runoff and a portion of runoff generated in Prospect Road along it’s frontage. The ultimate design of Lot 7 will need to follow FCSCM. Pond 1 has no emergency spillway location because it is located at the lowest point in the entire drainage basin. If it backs up due to poor maintenance of the outlet structure it will cause backwater conditions along Prospect Road. Pond 2 has an emergency spill location located near the outlet structure. The trail along the north side of the TRIC was designed to stabilize this overtopping location. If Pond 2 begins to overtop the runoff will overtop the southern bank of Pond 2 and discharge into the TRIC. No weir is needed to direct emergency flows to the south into the TRIC. Pond 3 has an emergency spill location at the northwest corner of Vixen Drive and Carriage Parkway. A berm was designed on the eastern portion of the pond, south of Lot 13, so that all overtopping occurs at the intersection and does not discharge into adjacent properties. The sidwalk along the right-of-way will serve as the stablazing spillway location. No weir is needed to direct emergency flows to the northwest corner of Vixen Drive and Carriage Parkway. All the rain gardens have designed overflow weirs. The drainage exhibit should be used as a reference as to where these weirs are located. However, for additional clarity on these weirs please refer to sheets RG1-RG4 in the utility plans. For finish grade elevations please refer to the sheets G1-G9 of the utility plans. All spill locations associated with either the ponds or rain gardens have also been reinforced with a turf reinforcement that has been designed to handle all the 100-year flows. The turf reinforcement has a warranty of 10+ years. CONCLUSIONS A. COMPLIANCE WITH STANDARDS The drainage design proposed with the Rudolph Farm project does comply with the City of Fort Collins Stormwater Criteria Manual, Timnath Stormwater Master Plan, and Mile High Flood Control District Criteria Manual. There are regulatory floodplains associated with the Rudolph Farm development. However, the floodplains will be unaltered by this development. NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: GATEWAY TO PROSPECT FORT COLLINS | GREELEY APPENDIX APPENDIX A HYDROLOGIC COMPUTATIONS (EXISTING SWMM AND RATIONAL) Project:Rudolph Farm Calculations By:B. Mathisen Date:May 1, 2023 CHARACTER OF SURFACE1: Percentage Impervious 2-yr Runoff Coefficient 100-yr Runoff Coefficient Streets, Parking Lots, Roofs, Alleys, and Drives: Asphalt ……....……………...……….....…...……………….….…………………………..………………………………………………………………………………………………………..100%0.95 1.00 Concrete …….......……………….….……….…….…………………………..…………………………………………………………..….……………………………………………………..100%0.95 1.00 Gravel ……….…………………….….…………………………..……………………………………………….…………………………..………………………………………………………40%0.50 0.63 Roofs …….…….………………..……………….…………………………………………………………………...............................................………90%0.95 1.00 Lawns and Landscaping Sandy Soil - Avg. Slope (2% - 7%)…...................................................................................................................................2%0.15 0.19 Clayey Soil - Avg. Slope (2% - 7%)…........................................................................................................................2%0.25 0.31 ROW Width Asphalt Concrete Area Landscaped Area Percent Impervious LF LF LF SF % ROW (Collector w/ Parking 84' ROW)84 54 10 20 77% 0.78 0.98 ROW (Collector 118' ROW - Prospect Intersection)118 91 10 17 86% 0.85 1.00 ROW (Commercail Local 77' ROW)77 50 10 17 78% 0.80 0.99 ROW (Industrial Local 71' ROW)71 44 10 17 77% 0.78 0.98 ROW (Prospect Frontage (Half ROW))72 57.5 6 8.5 88%0.87 1.00 UPDATED TO FCSCM 2018 RUNOFF COEFFICIENT (FROM CHAPTER 3 OF FCSCM) SITE SPECIFIC % IMPERVIOUSNESS Right of Way Classification C2 C100 5/1/202310:40 AM P:\1896-001\Drainage\Hydrology\1896-001_Proposed Rational Calcs.xlsx CHARACTER OF SURFACE1: Percentage Impervious 2-yr Runoff Coefficient 100-yr Runoff Coefficient Developed ROW (Collector w/ Parking 84' ROW).…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………77%0.78 0.98 ROW (Collector 118' ROW - Prospect Intersection).…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………86%0.85 1.00 ROW (Commercail Local 77' ROW).…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………78%0.80 0.99 ROW (Industrial Local 71' ROW).…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………77%0.78 0.98 ROW (Prospect Frontage (Half ROW)).…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………88%0.87 1.00 Urban Estate .…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………30%0.30 0.38 Commercial .…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………80%0.85 1.00 Industrial .…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………90%0.95 1.00 Concrete and Asphalt .…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………100%0.95 1.00 Unimproved Areas Undeveloped, Greenbelts, agricultural .…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………2%0.20 0.25 Lawns Sandy Soil .…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..……………………………………………….…………………………..………………………………………………2%0.20 0.25 Notes: Basin ID Basin Area (ac) Area of Collector 84' R.O.W (ac) Area of Collector 110' R.O.W (ac) Area of Commercial 77' R.O.W (ac) Area of Industrial 71' R.O.W (ac) Area of Urban Estate (ac) Area of Commercial (ac) Area of Industrial (ac) Area of Half ROW Prospect (ac) Area of Concrete/A sphalt (ac) Area of Undeveloped, Greenbelts, Agricultural (ac) Composite % Imperv. 2-year Composite Runoff Coefficient 100-year Composite Runoff Coefficient 1 6.80 0.00 0.00 0.00 0.00 0.00 6.80 0.00 0.00 0.00 0.00 80% 0.85 1.00 2 1.47 0.00 0.00 0.00 0.00 0.00 1.47 0.00 0.00 0.00 0.00 80% 0.85 1.00 3 1.43 0.00 0.00 0.00 0.00 0.00 1.43 0.00 0.00 0.00 0.00 80% 0.85 1.00 4A 1.43 0.00 0.00 0.00 0.00 0.00 1.43 0.00 0.00 0.00 0.00 80% 0.85 1.00 4B 0.99 0.00 0.00 0.00 0.00 0.00 0.99 0.00 0.00 0.00 0.00 80% 0.85 1.00 5 1.10 0.00 0.00 0.00 0.00 0.00 1.10 0.00 0.00 0.00 0.00 80% 0.85 1.00 6 2.59 0.00 0.00 0.00 0.00 0.00 2.59 0.00 0.00 0.00 0.00 80%0.85 1.00 7 6.67 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.73 0.00 5.94 11% 0.27 0.34 8A 5.74 0.00 0.00 0.00 0.00 0.00 0.00 5.74 0.00 0.00 0.00 90% 0.95 1.00 8B 2.16 0.00 0.00 0.00 0.00 0.00 0.00 2.16 0.00 0.00 0.00 90% 0.95 1.00 9A 10.76 0.00 0.00 0.00 0.00 0.00 0.00 10.76 0.00 0.00 0.00 90% 0.95 1.00 9B 3.97 0.00 0.00 0.00 0.00 0.00 0.00 3.97 0.00 0.00 0.00 90% 0.95 1.00 10 9.47 0.00 0.00 0.00 0.00 0.00 0.00 9.47 0.00 0.00 0.00 90% 0.95 1.00 11 3.28 0.00 0.00 0.00 0.00 0.00 0.00 3.28 0.00 0.00 0.00 90% 0.95 1.00 12 13.50 0.00 0.00 0.00 0.00 0.00 0.00 13.50 0.00 0.00 0.00 90% 0.95 1.00 13 8.85 0.00 0.00 0.00 0.00 8.85 0.00 0.00 0.00 0.00 0.00 30% 0.30 0.38 R1 1.31 0.39 0.42 0.51 0.00 0.00 0.00 0.00 0.00 0.00 0.00 80% 0.81 1.00 R2 1.36 0.41 0.46 0.00 0.00 0.00 0.00 0.00 0.50 0.00 0.00 84% 0.84 1.00 R3 1.44 0.00 0.00 1.01 0.43 0.00 0.00 0.00 0.00 0.00 0.00 78% 0.79 0.99 R4 1.11 0.00 0.00 1.11 0.00 0.00 0.00 0.00 0.00 0.00 0.00 78% 0.80 1.00 R5 2.83 1.73 0.00 0.00 1.09 0.00 0.00 0.00 0.00 0.00 0.00 77% 0.78 0.98 R6 1.98 1.98 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 77% 0.78 0.98 R7 0.94 0.00 0.00 0.00 0.57 0.00 0.00 0.37 0.00 0.00 0.00 82% 0.85 1.00 R8 0.86 0.44 0.00 0.00 0.00 0.21 0.00 0.21 0.00 0.00 0.00 69% 0.71 0.89 R9 0.40 0.00 0.00 0.40 0.00 0.00 0.00 0.00 0.00 0.00 0.00 78% 0.80 1.00 R10 0.27 0.00 0.00 0.27 0.00 0.00 0.00 0.00 0.00 0.00 0.00 78% 0.80 1.00 R11 0.24 0.24 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 77% 0.78 0.98 R12 0.59 0.00 0.00 0.59 0.00 0.00 0.00 0.00 0.00 0.00 0.00 78% 0.80 1.00 R13 0.54 0.00 0.00 0.54 0.00 0.00 0.00 0.00 0.00 0.00 0.00 78% 0.80 1.00 OS1 5.16 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.27 4.89 7% 0.24 0.30 OS2 1.33 0.00 0.18 0.00 0.00 0.00 0.00 0.00 1.15 0.00 0.00 88% 0.86 1.00 OS3 3.76 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.76 2% 0.20 0.25 OS4 5.55 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.35 5.20 8% 0.25 0.31 OS5 3.10 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.10 2% 0.20 0.25 OS6 1.23 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.23 2% 0.20 0.25 OS7 0.42 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.42 2% 0.20 0.25 DC1 2.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.02 2% 0.20 0.25 DC2 2.21 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.21 2% 0.20 0.25 DC3 3.54 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.54 2% 0.20 0.25 FG1 0.27 0.27 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 77% 0.78 0.98 DP r1 (Basin 4B and R1)2.30 0.39 0.42 0.51 0.00 0.00 0.99 0.00 0.00 0.00 0.00 80%0.83 1.00 DP r2 (Basin 5, 6 & R2)5.05 0.41 0.46 0.00 0.00 0.00 3.69 0.00 0.50 0.00 0.00 81%0.85 1.00 RG 1 (Basin 1-4, R1, R12, & R13)14.56 0.39 0.42 1.64 0.00 0.00 11.12 0.00 0.99 0.00 0.00 80%0.84 1.00 Standard WQ Pond 1 (Basin 5, 6, R2, OS1, & OS2)11.55 0.41 0.64 0.00 0.00 0.00 3.69 0 1.65 0.27 4.89 49% 0.58 0.73 DP r3 (Basin 9A & R3)12.21 0.00 0.00 1.01 0.43 0.00 0.00 10.76 0.00 0.00 0.00 89%0.93 1.00 RG 2 (Basin 8A, 9A, & R3)17.94 0.00 0.00 1.01 0.43 0.00 0.00 16.50 0.00 0.00 0.00 89%0.94 1.00 RG 3 (Basin 10, R4, & R5)13.41 1.73 0.00 1.11 1.09 0.00 0.00 9.47 0.00 0.00 0.00 86%0.90 1.00 Standard WQ Pond 2 (Basin 8B, 9B, 11, R6, R7, R8, R9, R10, R11, OS4, OS5, OS6, & OS7)24.39 2.66 0.00 0.67 0.57 0.21 0.00 9.98 0.00 0.35 9.94 52% 0.61 0.76 DP r9 (Basin 9A, R3, & R9)12.61 0.00 0.00 1.41 0.43 0.00 0.00 10.76 0.00 0.00 0.00 88%0.93 1.00 DP r10 (Basin R4 & R10)1.38 0.00 0.00 1.38 0.00 0.00 0.00 0.00 0.00 0.00 0.00 78%0.80 1.00 DP r11 (Basin R5 & R11)3.06 1.97 0.00 0.00 1.09 0.00 0.00 0.00 0.00 0.00 0.00 77%0.78 0.98 DP r13 (Basin R13 & 4A) 1.96 0.00 0.00 0.54 0.00 0.00 1.43 0.00 0.00 0.00 0.00 80% 0.84 1.00 PROPOSED BASIN % IMPERVIOUSNESS AND RUNOFF COEFFICIENT CALCULATIONS 2) Runoff Coefficients are taken from the Fort Collins Stormwater Criteria Manual, Chapter 3. Table 3.2-1 and 3.2-2 1) Percentage impervious taken from the Fort Collins Stormwater Criteria Manual, Chapter 5, Table 4.1-2 and Table 4.1-3 Combined Basins Overland Flow, Time of Concentration:Total Time of Concentration : Channelized Flow, Time of Concentration:T c is the lesser of the values of Tc calculated using T c = T i + T t C2 C100 Length, L (ft) Slope, S (%) Ti2 Ti100 Length, L (ft) Slope, S (%) Roughness Coefficient Assumed Hydraulic Radius Velocity, V (ft/s) Tt (min)Tc (Eq. 3.3-5) Tc2 = Ti +Tt Tc100 = Ti +Tt Tc2 Tc100 1 0.85 1.00 260 1.00%7.5 3.0 0 N/A N/A N/A N/A N/A 11.4 7.5 3.0 7.5 5.0 2 0.85 1.00 260 1.00%7.5 3.0 0 N/A N/A N/A N/A N/A 11.4 7.5 3.0 7.5 5.0 3 0.85 1.00 260 1.00%7.5 3.0 0 N/A N/A N/A N/A N/A 11.4 7.5 3.0 7.5 5.0 4A 0.85 1.00 240 1.00%7.2 2.9 0 N/A N/A N/A N/A N/A 11.3 7.2 2.9 7.2 5.0 4B 0.85 1.00 240 1.00%7.2 2.9 0 N/A N/A N/A N/A N/A 11.3 7.2 2.9 7.2 5.0 5 0.85 1.00 250 1.00%7.4 3.0 0 N/A N/A N/A N/A N/A 11.4 7.4 3.0 7.4 5.0 6 0.85 1.00 250 1.00%7.4 3.0 0 N/A N/A N/A N/A N/A 11.4 7.4 3.0 7.4 5.0 Pond 4 & RG 6 7 0.27 0.34 150 2.00%15.1 13.9 150 1.00%0.012 0.15 3.51 0.7 11.7 15.8 14.6 11.7 11.7 8A 0.95 1.00 200 2.00%3.1 2.1 0 N/A N/A N/A N/A N/A 11.1 3.1 2.1 5.0 5.0 8B 0.95 1.00 200 2.00%3.1 2.1 0 N/A N/A 0.15 N/A N/A 11.1 3.1 2.1 5.0 5.0 9A 0.95 1.00 500 1.60%5.4 3.6 0 N/A N/A N/A N/A N/A 12.8 5.4 3.6 5.4 5.0 9B 0.95 1.00 500 1.60%5.4 3.6 0 N/A N/A N/A N/A N/A 12.8 5.4 3.6 5.4 5.0 10 0.95 1.00 450 1.00%6.0 4.0 0 N/A N/A N/A N/A N/A 12.5 6.0 4.0 6.0 5.0 11 0.95 1.00 320 1.00%5.0 3.3 0 N/A N/A N/A N/A N/A 11.8 5.0 3.3 5.0 5.0 RG 4 12 0.95 1.00 500 1.00%6.3 4.2 0 N/A N/A N/A N/A N/A 12.8 6.3 4.2 6.3 5.0 RG 5 13 0.30 0.38 500 1.00%33.5 30.3 0 N/A N/A N/A N/A N/A 12.8 33.5 30.3 12.8 12.8 R1 0.81 1.00 14 2.00%1.6 0.5 1200 0.70%0.012 0.15 2.94 6.8 16.7 8.4 7.3 8.4 7.3 R2 0.84 1.00 14 2.00%1.4 0.5 450 1.11%0.012 0.15 3.69 2.0 12.6 3.4 2.6 5.0 5.0 R3 0.79 0.99 14 2.00%1.7 0.6 2000 0.70%0.012 0.15 2.93 11.4 21.2 13.1 12.0 13.1 12.0 r4 R4 0.80 1.00 14 2.00%1.6 0.5 1100 0.70%0.012 0.15 2.93 6.3 16.2 7.9 6.8 7.9 6.8 r5 R5 0.78 0.98 14 2.00%1.7 0.7 1980 0.60%0.012 0.15 2.71 12.2 21.1 13.9 12.9 13.9 12.9 r6 R6 0.78 0.98 14 2.00%1.7 0.7 1980 0.60%0.012 0.15 2.71 12.2 21.1 13.9 12.9 13.9 12.9 r7 R7 0.85 1.00 90 2.00%3.5 1.4 180 1.00%0.012 0.15 3.51 0.9 11.5 4.4 2.3 5.0 5.0 r8 R8 0.71 0.89 90 2.00%5.5 3.0 180 2.25%0.012 0.15 5.26 0.6 11.5 6.1 3.6 6.1 5.0 R9 0.80 1.00 14 2.00%1.6 0.5 350 1.40%0.012 0.15 4.15 1.4 12.0 3.0 2.0 5.0 5.0 R10 0.80 1.00 14 2.00%1.6 0.5 180 2.25%0.012 0.15 5.26 0.6 11.1 2.2 1.1 5.0 5.0 R11 0.78 0.98 14 2.00%1.7 0.7 150 0.60%0.012 0.15 2.72 0.9 10.9 2.7 1.6 5.0 5.0 r12 R12 0.80 1.00 14 2.00%1.6 0.5 500 0.50%0.012 0.15 2.48 3.4 12.9 5.0 3.9 5.0 5.0 R13 0.80 1.00 14 2.00%1.6 0.5 500 0.50%0.012 0.15 2.48 3.4 12.9 5.0 3.9 5.0 5.0 OS1 0.24 0.30 50 2.00%9.0 8.4 0 N/A N/A N/A N/A N/A 10.3 9.0 8.4 9.0 8.4 OS2 0.86 1.00 45 2.24%2.3 1.0 0 N/A N/A N/A N/A N/A 10.3 2.3 1.0 5.0 5.0 OS3 0.20 0.25 210 0.60%29.0 27.4 0 N/A N/A N/A N/A N/A 11.2 29.0 27.4 11.2 11.2 OS4 0.25 0.31 50 2.00%8.9 8.3 0 N/A N/A N/A N/A N/A 10.3 8.9 8.3 8.9 8.3 OS5 0.20 0.25 50 2.00%9.4 8.9 0 N/A N/A N/A N/A N/A 10.3 9.4 8.9 9.4 8.9 os6 OS6 0.20 0.25 25 20.00%3.1 2.9 1000 0.50%0.012 0.77 7.38 2.3 15.7 5.4 5.2 5.4 5.2 os7 OS7 0.20 0.25 25 20.00%3.1 2.9 350 0.50%0.012 0.77 7.38 0.8 12.1 3.9 3.7 5.0 5.0 DC1 0.20 0.25 50 22.00%4.2 4.0 333 0.13%0.025 4.40 5.68 1.0 12.1 5.2 5.0 5.2 5.0 DC2 0.20 0.25 50 22.00%4.2 4.0 333 0.13%0.025 4.40 5.68 1.0 12.1 5.2 5.0 5.2 5.0 DC3 0.20 0.25 50 22.00%4.2 4.0 333 0.13%0.025 4.40 5.68 1.0 12.1 5.2 5.0 5.2 5.0 FG1 0.78 0.98 20 2.00% 2.1 0.8 150 0.50% 0.025 4.40 11.32 0.2 10.9 2.3 1.1 5.0 5.0 r1 DP r1 (Basin 4B and R1)0.83 1.00 240 1.00%7.8 2.9 1200 0.70%0.012 0.15 2.94 6.8 18.0 14.6 9.7 14.6 9.7 r2 DP r2 (Basin 5, 6 & R2)0.85 1.00 250 1.00%7.4 3.0 750 0.67%0.012 0.15 2.86 4.4 15.6 11.8 7.3 11.8 7.3 RG 1 RG 1 (Basin 1-4, R1, R12, & R13)0.84 1.00 250 1.00%7.7 3.0 1200 0.70%0.012 0.15 2.94 6.8 18.1 14.5 9.8 14.5 9.8 Pond 1 Standard WQ Pond 1 (Basin 5, 6, R2, OS1, & OS2)0.58 0.73 250 1.00% 15.4 11.1 1200 0.70% 0.012 0.15 2.94 6.8 18.1 22.2 17.9 18.1 17.9 r3 DP r3 (Basin 9A & R3)0.93 1.00 500 1.60%6.1 3.6 2000 0.70%0.012 0.15 2.93 11.4 23.9 17.4 14.9 17.4 14.9 RG 2 RG 2 (Basin 8A, 9A, & R3)0.94 1.00 500 1.60%5.7 3.6 2000 0.70%0.012 0.15 2.93 11.4 23.9 17.1 14.9 17.1 14.9 RG 3 RG 3 (Basin 10, R4, & R5)0.90 1.00 450 1.00%7.9 4.0 1980 0.60%0.012 0.15 2.71 12.2 23.5 20.1 16.2 20.1 16.2 Pond 2 Standard WQ Pond 2 (Basin 8B, 9B, 11, R6, R7, R8, R9, R10, R11, OS4, OS5, OS6, & OS7) 0.61 0.76 500 1.60% 17.5 12.1 1980 0.60% 0.012 0.15 2.71 12.2 23.8 29.7 24.3 23.8 23.8 r9 DP r9 (Basin 9A, R3, & R9)0.93 1.00 14 2.00%0.9 0.5 2000 0.70%0.012 0.15 2.93 11.4 21.2 12.3 11.9 12.3 11.9 r10 DP r10 (Basin R4 & R10)0.80 1.00 14 2.00%1.6 0.5 1100 0.70%0.012 0.15 2.93 6.3 16.2 7.9 6.8 7.9 6.8 r11 DP r11 (Basin R5 & R11)0.78 0.98 14 2.00%1.7 0.7 1980 0.60%0.012 0.15 2.71 12.2 21.1 13.9 12.9 13.9 12.9 r13 DP r13 (Basin R13 & 4A) 0.84 1.00 240 1.00% 7.5 2.9 500 0.50% 0.012 0.15 2.48 3.4 14.1 10.9 6.3 10.9 6.3 Combined Basins PROPOSED DEVELOPED DIRECT TIME OF CONCENTRATION Channelized Flow Design Point Basin Overland Flow Time of Concentration (Equation 3.3-2 FCSCM) (Equation 5-5 FCSCM) (Equation 5-4 FCSCM) (Equation 3.3-5 FCSCM) Rational Method Equation: Rainfall Intensity: 1 6.80 7.5 5.0 0.85 1.00 2.46 9.95 14.22 67.68 2 1.47 7.5 5.0 0.85 1.00 2.46 9.95 3.07 14.60 3 1.43 7.5 5.0 0.85 1.00 2.46 9.95 2.99 14.22 4A 1.43 7.2 5.0 0.85 1.00 2.52 9.95 3.05 14.18 4B 0.99 7.2 5.0 0.85 1.00 2.52 9.95 2.12 9.87 5 1.10 7.4 5.0 0.85 1.00 2.52 9.95 2.37 10.99 6 2.59 7.4 5.0 0.85 1.00 2.52 9.95 5.54 25.74 Pond 4 & RG 6 7 6.67 11.7 11.7 0.27 0.34 2.09 7.29 3.76 16.41 8A 5.74 5.0 5.0 0.95 1.00 2.85 9.95 15.53 57.07 8B 2.16 5.0 5.0 0.95 1.00 2.85 9.95 5.86 21.54 9A 10.76 5.4 5.0 0.95 1.00 2.85 9.95 29.14 107.09 9B 3.97 5.4 5.0 0.95 1.00 2.85 9.95 10.74 39.48 10 9.47 6.0 5.0 0.95 1.00 2.76 9.95 24.84 94.27 11 3.28 5.0 5.0 0.95 1.00 2.85 9.95 8.87 32.61 RG 4 12 13.50 6.3 5.0 0.95 1.00 2.67 9.95 34.25 134.35 RG 5 13 8.85 12.8 12.8 0.30 0.38 2.02 7.04 5.35 23.37 R1 1.31 8.4 7.3 0.81 1.00 2.40 8.80 2.55 11.54 R2 1.36 5.0 5.0 0.84 1.00 2.85 9.95 3.26 13.54 R3 1.44 13.1 12.0 0.79 0.99 1.98 7.29 2.26 10.39 r4 R4 1.11 7.9 6.8 0.80 1.00 2.46 9.06 2.17 10.01 r5 R5 2.83 13.9 12.9 0.78 0.98 1.95 7.04 4.30 19.40 r6 R6 1.98 13.9 12.9 0.78 0.98 1.95 7.04 3.01 13.60 r7 R7 0.94 5.0 5.0 0.85 1.00 2.85 9.95 2.27 9.33 r8 R8 0.86 6.1 5.0 0.71 0.89 2.67 9.95 1.62 7.56 R9 0.40 5.0 5.0 0.80 1.00 2.85 9.95 0.91 3.98 R10 0.27 5.0 5.0 0.80 1.00 2.85 9.95 0.62 2.72 R11 0.24 5.0 5.0 0.78 0.98 2.85 9.95 0.53 2.30 r12 R12 0.59 5.0 5.0 0.80 1.00 2.85 9.95 1.35 5.88 R13 0.54 5.0 5.0 0.80 1.00 2.85 9.95 1.22 5.34 OS1 5.16 9.0 8.4 0.24 0.30 2.30 8.38 2.85 12.98 OS2 1.33 5.0 5.0 0.86 1.00 2.85 9.95 3.27 13.27 OS3 3.76 11.2 11.2 0.20 0.25 2.13 7.42 1.60 6.97 OS4 5.55 8.9 8.3 0.25 0.31 2.35 8.38 3.26 14.54 OS5 3.10 9.4 8.9 0.20 0.25 2.30 8.21 1.43 6.36 os6 OS6 1.23 5.4 5.2 0.20 0.25 2.85 9.95 0.70 3.06 os7 OS7 0.42 5.0 5.0 0.20 0.25 2.85 9.95 0.24 1.04 DC1 2.02 5.2 5.0 0.20 0.25 2.85 9.95 1.15 5.03 DC2 2.21 5.2 5.0 0.20 0.25 2.85 9.95 1.26 5.50 DC3 3.54 5.2 5.0 0.20 0.25 2.85 9.95 2.02 8.82 FG1 0.27 5.0 5.0 0.78 0.98 2.85 9.95 0.60 2.63 r1 DP r1 (Basin 4B and R1)2.30 14.6 9.7 0.83 1.00 1.90 7.88 3.62 18.14 r2 DP r2 (Basin 5, 6 & R2)5.05 11.8 7.3 0.85 1.00 2.09 8.80 8.98 44.47 RG 1 RG 1 (Basin 1-4, R1, R12, & R13)14.56 14.5 9.8 0.84 1.00 1.92 7.88 23.47 114.62 Pond 1 Standard WQ Pond 1 (Basin 5, 6, R2, OS1, & OS2)11.55 18.1 17.9 0.58 0.73 1.70 6.01 11.39 50.32 r3 DP r3 (Basin 9A & R3)12.21 17.4 14.9 0.93 1.00 1.75 6.62 19.86 80.74 RG 2 RG 2 (Basin 8A, 9A, & R3)17.94 17.1 14.9 0.94 1.00 1.75 6.62 29.51 118.68 RG 3 RG 3 (Basin 10, R4, & R5)13.41 20.1 16.2 0.90 1.00 1.61 6.30 19.43 84.46 Pond 2 Standard WQ Pond 2 (Basin 8B, 9B, 11, R6, R7, R8, R9, R10, R11, OS4, OS5, OS6, & OS7) 24.39 23.8 23.8 0.61 0.76 1.48 5.15 21.95 95.69 r9 DP r9 (Basin 9A, R3, & R9)12.61 12.3 11.9 0.93 1.00 2.05 7.29 24.03 91.89 r10 DP r10 (Basin R4 & R10)1.38 7.9 6.8 0.80 1.00 2.46 9.06 2.71 12.49 r11 DP r11 (Basin R5 & R11)3.06 13.9 12.9 0.78 0.98 1.95 7.04 4.66 21.03 r13 DP r13 (Basin R13 & 4A) 1.96 10.9 6.3 0.84 1.00 2.17 9.31 3.58 18.27 PROPOSED DEVELOPED RUNOFF COMPUTATIONS Design Point Basin(s)Area, A (acres) Tc2 (min) Flow, Q2 (cfs) Flow, Q100 (cfs) C2 C100 IDF Table for Rational Method - Table 3.4-1 FCSCM Combined Basins Tc100 (min) Intensity, i2 (in/hr) Intensity, i100 (in/hr) ()()()AiCCQf= BASIN TOTAL AREA (acres) Tc2 (min) Tc100 (min) C2 C100 Q2 (cfs) Q100 (cfs) 1 6.80 7.5 5.0 0.85 1.00 14.22 67.68 2 1.47 7.5 5.0 0.85 1.00 3.07 14.60 3 1.43 7.5 5.0 0.85 1.00 2.99 14.22 4A 1.43 7.2 5.0 0.85 1.00 3.05 14.18 4B 0.99 7.2 5.0 0.85 1.00 2.12 9.87 5 1.10 7.4 5.0 0.85 1.00 2.37 10.99 6 2.59 7.4 5.0 0.85 1.00 5.54 25.74 7 6.67 11.7 11.7 0.27 0.34 3.76 16.41 8A 5.74 5.0 5.0 0.95 1.00 15.53 57.07 8B 2.16 5.0 5.0 0.95 1.00 5.86 21.54 9A 10.76 5.4 5.0 0.95 1.00 29.14 107.09 9B 3.97 5.4 5.0 0.95 1.00 10.74 39.48 10 9.47 6.0 5.0 0.95 1.00 24.84 94.27 11 3.28 5.0 5.0 0.95 1.00 8.87 32.61 12 13.50 6.3 5.0 0.95 1.00 34.25 134.35 13 8.85 12.8 12.8 0.30 0.38 5.35 23.37 R1 1.31 8.4 7.3 0.81 1.00 2.55 11.54 R2 1.36 5.0 5.0 0.84 1.00 3.26 13.54 R3 1.44 13.1 12.0 0.79 0.99 2.26 10.39 R4 1.11 7.9 6.8 0.80 1.00 2.17 10.01 R5 2.83 13.9 12.9 0.78 0.98 4.30 19.40 R6 1.98 13.9 12.9 0.78 0.98 3.01 13.60 R7 0.94 5.0 5.0 0.85 1.00 2.27 9.33 R8 0.86 6.1 5.0 0.71 0.89 1.62 7.56 R9 0.40 5.0 5.0 0.80 1.00 0.91 3.98 R10 0.27 5.0 5.0 0.80 1.00 0.62 2.72 R11 0.24 5.0 5.0 0.78 0.98 0.53 2.30 R12 0.59 5.0 5.0 0.80 1.00 1.35 5.88 R13 0.54 5.0 5.0 0.80 1.00 1.22 5.34 OS1 5.16 9.0 8.4 0.24 0.30 2.85 12.98 OS2 1.33 5.0 5.0 0.86 1.00 3.27 13.27 OS3 3.76 11.2 11.2 0.20 0.25 1.60 6.97 OS4 5.55 8.9 8.3 0.25 0.31 3.26 14.54 OS5 3.10 9.4 8.9 0.20 0.25 1.43 6.36 OS6 1.23 5.4 5.2 0.20 0.25 0.70 3.06 OS7 0.42 5.0 5.0 0.20 0.25 0.24 1.04 DC1 2.02 5.2 5.0 0.20 0.25 1.15 5.03 DC2 2.21 5.2 5.0 0.20 0.25 1.26 5.50 DC3 3.54 5.2 5.0 0.20 0.25 2.02 8.82 FG1 0.27 5.0 5.0 0.78 0.98 0.60 2.63 DP r1 (Basin 4B and R1)2.30 14.6 9.7 0.83 1.00 3.62 18.14 DP r2 (Basin 5, 6 & R2)5.05 11.8 7.3 0.85 1.00 8.98 44.47 RG 1 (Basin 1-4, R1, R12, & R13)14.56 14.5 9.8 0.84 1.00 23.47 114.62 Standard WQ Pond 1 (Basin 5, 6, R2, OS1, & OS2)11.55 18.1 17.9 0.58 0.73 11.39 50.32 DP r3 (Basin 9A & R3)12.21 17.4 14.9 0.93 1.00 19.86 80.74 RG 2 (Basin 8A, 9A, & R3)17.94 17.1 14.9 0.94 1.00 29.51 118.68 RG 3 (Basin 10, R4, & R5)13.41 20.1 16.2 0.90 1.00 19.43 84.46 Standard WQ Pond 2 (Basin 8B, 9B, 11, R6, R7, R8, R9, R10, R11, OS4, OS5, OS6, & OS7)24.39 23.8 23.8 0.61 0.76 21.95 95.69 DP r9 (Basin 9A, R3, & R9)12.61 12.3 11.9 0.93 1.00 24.03 91.89 DP r10 (Basin R4 & R10)1.38 7.9 6.8 0.80 1.00 2.71 12.49 DP r11 (Basin R5 & R11)3.06 13.9 12.9 0.78 0.98 4.66 21.03 DP r13 (Basin R13 & 4A) 1.96 10.9 6.3 0.84 1.00 3.58 18.27 Rational Flow Summary |Proposed Developed Basin Flow Rates Combined Basins 5/1/202310:40 AM P:\1896-001\Drainage\Hydrology\1896-001_Proposed Rational Calcs.xlsx\Summary Tables Major event flows to Lake Canal: Q100 from DC1-DC3 = 19.35 cfs NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: RUDOLPH FARM FORT COLLINS | GREELEY APPENDIX APPENDIX B HYDRAULIC COMPUTATIONS B.1 – STORM SEWERS AND BOX CULVERTS 1 Blaine Mathisen From:Andy Reese Sent:Tuesday, October 4, 2022 4:49 PM To:Blaine Mathisen Subject:FW: Rudolph Submittal - 2.0 Follow Up Flag:Follow up Flag Status:Flagged Hey – can you follow up with Scott on Rudolph/Lake Canal? Andy Reese Director of Land Development/Vice-President Please note that I will be out of the office 10/7 – 10/12, and returning 10/14. Survey | Municipal | Land Development D: 970.568.5403 | O: 970.221.4158 From: Scott Parker <Scott.Parker@acewater.com> Sent: Tuesday, October 4, 2022 4:46 PM To: Andy Reese <andy@northernengineering.com> Subject: RE: Rudolph Submittal - 2.0 Andy, What was the maximum design discharge for the proposed box culverts on Lake Canal? I noticed in the drainage report that the maximum design discharge in the HY-8 model was 200 CFS, which included a 50 CFS safety factor over the 150 CFS maximum discharge provided by the ditch company. This was accomplished in Lake Canal Crossing A with a design slope of 0.0004 ft/ft over 780 feet of culvert (page 81 of the PDF). The proposed plans show a slope of 0.0002 ft/ft over 862 feet of culvert on Crossing A (sheets LC1 and LC2). The decree for the ditch company is 158 CFS, which would be the maximum discharge I would have recommended. Can you confirm that the culverts as shown on the design plans will carry at least the 150 CFS discharge noted or, preferably, the 158 CFS decree, with reasonable freeboard upstream? Feel free to call if you would like to discuss, I should be in the office most of the day tomorrow. Regards, Scott R. Parker, P.E. Anderson Consulting Engineers, Inc. 375 E. Horsetooth Rd., Bldg. 5 Fort Collins, CO 80525 Ph. 970-226-0120 From: Andy Reese <andy@northernengineering.com> Sent: Monday, October 03, 2022 4:22 PM To: Scott Parker <Scott.Parker@acewater.com> Subject: Rudolph Submittal - 2.0 This email shows the basis for the 158 cfs for the Lake Canal culvert sizing. We are working with Scott Parker, from Anderson Consulting, for the Lake Canal culverts. 2 Hey Scott – It looks like our system just isn’t going to send the files, so I’ve created a different share using OneDrive. Here is a link to the files: Round 1 Final The folder contains our Utility Plans, Plat and Drainage Report. I’ve also included a conceptual land use file that shows the current thinking for the various parcels out there. Those are definitely subject to change! Sorry for the trouble with Newforma – hopefully this gets you what you need! Andy Reese Director of Land Development/Vice-President Survey | Municipal | Land Development D: 970.568.5403 | O: 970.221.4158 HY-8 Culvert Analysis Report Crossing Discharge Data Discharge Selection Method: Specify Minimum, Design, and Maximum Flow Minimum Flow: 10.00 cfs Design Flow: 158.00 cfs Maximum Flow: 158.00 cfs Table 1 - Summary of Culvert Flows at Crossing: PROSPECT ROAD Headwater Elevation (ft) Total Discharge (cfs) LAKE CANAL-A Discharge (cfs) Roadway Discharge (cfs) Iterations 11.16 10.00 10.00 0.00 1 11.70 24.80 24.80 0.00 1 12.10 39.60 39.60 0.00 1 12.44 54.40 54.40 0.00 1 12.74 69.20 69.20 0.00 1 13.01 84.00 84.00 0.00 1 13.26 98.80 98.80 0.00 1 13.49 113.60 113.60 0.00 1 13.71 128.40 128.40 0.00 1 13.92 143.20 143.20 0.00 1 14.11 158.00 158.00 0.00 1 16.82 320.40 320.40 0.00 Overtopping LAKE CANAL - CROSSING A Rating Curve Plot for Crossing: PROSPECT ROAD Culvert Data: LAKE CANAL-A Table 2 - Culvert Summary Table: LAKE CANAL-A Total Discharge (cfs) Culvert Discharge (cfs) Headwater Elevation (ft) Inlet Control Depth (ft) Outlet Control Depth (ft) Normal Depth (ft) Critical Depth (ft) Outlet Depth (ft) Tailwater Depth (ft) Outlet Velocity (ft/s) Tailwater Velocity (ft/s) 10.00 cfs 10.00 cfs 11.16 0.37 0.683 0.60 0.24 0.73 0.73 0.91 0.71 24.80 cfs 24.80 cfs 11.70 0.68 1.215 1.05 0.44 1.24 1.24 1.34 0.97 39.60 cfs 39.60 cfs 12.10 0.92 1.619 1.42 0.60 1.61 1.61 1.64 1.13 54.40 cfs 54.40 cfs 12.44 1.14 1.958 1.74 0.74 1.92 1.92 1.89 1.24 69.20 cfs 69.20 cfs 12.74 1.34 2.258 2.04 0.87 2.19 2.19 2.10 1.34 84.00 cfs 84.00 cfs 13.01 1.52 2.529 2.31 0.99 2.44 2.44 2.30 1.42 98.80 cfs 98.80 cfs 13.26 1.70 2.778 2.58 1.10 2.66 2.66 2.48 1.49 113.60 cfs 113.60 cfs 13.49 1.86 3.011 2.83 1.21 2.86 2.86 2.65 1.55 128.40 cfs 128.40 cfs 13.71 2.02 3.230 3.08 1.32 3.06 3.06 2.80 1.61 143.20 cfs 143.20 cfs 13.92 2.18 3.437 3.31 1.41 3.24 3.24 2.95 1.66 158.00 cfs 158.00 cfs 14.11 2.33 3.634 3.54 1.51 3.41 3.41 3.09 1.70 Culvert Barrel Data Culvert Barrel Type Straight Culvert Inlet Elevation (invert): 10.48 ft, Outlet Elevation (invert): 10.30 ft Culvert Length: 862.47 ft, Culvert Slope: 0.0002 Culvert Performance Curve Plot: LAKE CANAL-A Water Surface Profile Plot for Culvert: LAKE CANAL-A Site Data - LAKE CANAL-A Site Data Option: Culvert Invert Data Inlet Station: 0.00 ft Inlet Elevation: 10.48 ft Outlet Station: 862.47 ft Outlet Elevation: 10.30 ft Number of Barrels: 1 Culvert Data Summary - LAKE CANAL-A Barrel Shape: Concrete Box Barrel Span: 15.00 ft Barrel Rise: 4.00 ft Barrel Material: Concrete Embedment: 0.00 in NORTHERNENGINEERING.COM | 970.221.4158 FINAL DRAINAGE REPORT: RUDOLPH FARM FORT COLLINS | GREELEY APPENDIX APPENDIX D STANDARD WATER QUALITY AND LID Design Point (Basin Id)1 Total Area (ac) Treatment Method Area Treated (ac) Percent Impervious (%) Area of Impervious (ac)2 Required Standard Water Quality (cu. ft.) Required LID (cu. ft.) Provided LID (cu. ft.) RG1 14.57 Rain Garden 14.57 80%11.66 N/A 13,892 19,709 Standard WQ Pond 1 11.55 Standard WQ 11.55 49%5.66 10,241 N/A RG 2 17.94 Rain Garden 17.94 89%15.97 N/A 20,481 26,422 RG 3 13.41 Rain Garden 13.41 86%11.53 N/A 14,389 19,079 Standard WQ Pond 2 24.54 Standard WQ 24.54 52%12.76 22,638 N/A RG 4 13.50 Rain Garden 13.50 90%12.15 N/A 15,740 20,211 RG 5 8.85 Rain Garden 8.85 30%2.66 N/A 3,893 4,918 Impervious Area Treated Standard WQ Totals 36.09 Standard WQ 36.09 N/A 18.42 25% Rain Garden Totals 68.27 Rain Garden 68.27 N/A 53.96 75% 1. Refer to Rational Calculations for additional clarification. Some are stand alone basins and some are part of combined basins. * indicates a combined basin. 2. Calculated by multiplying the percent impervious by area treated 3. RG = Raingarden WQ = Water Quality Standard Water Quality and LID Summary Table S H2O H2O H2O H2O H2OH2O H2O WV WV W S C C C W CCW E CABLE H2O WVWV W W SS V.P. V.P. V.P.V.P. CABLE MM C S MMM W T H2O M 1 2 3 4 5 G 0 G 4 3 2 1 1 2 3 4 5 G 0 G 4 3 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NO P A R K I N G NO P A R K I N G / / / / / / / / SB SB KIT DEN DR.HUNTSMAN DR. 8" S S G G G G G G G T G 12" SS TSALPOLYN DUCTILEIRON 8" W 8" W 8" W F F 1 2 " S S T 8" W F E S FES DD B MB M util LID F ES F ES D D FESFES D D D D DD MM / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / UD U D FO POND 1 - DETENTION AND STANDARD WATER QUALITY RAIN GARDEN 1 POND 2 - DETENTION AND STANDARD WATER QUALITY RAIN GARDEN 2 RAIN GARDEN 4 RAIN GARDEN 5 POND 3 - DETENTION ONLY RAIN GARDEN 3 LOT 1 LOT 2 LOT 3 LOT 4 LOT 6 LOT 5 LOT 11 LOT 8 LOT 9 LOT 10 LOT 12 LOT 13 LOT 7 PRO S P E C T R I D G E D R I V E V I X E N D R I V E CARR I A G E P A R K W A Y PROSPECT ROAD LID EXHIBIT FORT COLLINS, CO RUDOLPH FARM E N G I N E E R N GI EHTRON R N 02.22.2023 P:\1896-001\DWG\SHEETS\DRAINAGE\1896-001_LID.DWG Design Point Area of Impervious (ac) RG1 11.66 Standard WQ Pond 1 5.66 RG 2 15.97 RG 3 11.53 Standard WQ Pond 2 12.76 RG 4 12.15 RG 5 2.66 Standard WQ Totals 18.42 25% Rain Garden Totals 53.96 75% TOTAL AREA (ac) PERCENTAGE OF IMPERVIOUS AREA NOTES: 1.Refer to Rudolph Farm Utility Plans for additional clarification on basin breakdowns, grading, and utility sizing. 2.Refer to Rudolph Farm Drainage Report for additional clarification on basin break downs, LID and standard water quality calculations. LID SUMMARY AND LEGEND: NORTH ( IN FEET ) 0 1 INCH = 300 FEET 300 300 600 900 LOT 7 WILL PROVIDE INTERIM WATER QUALITY BUT AT THE TIME OF FUTURE DEVELOPMENT LOT 7 WILL BE REQUIRED TO PROVIDE LID Project: Date: Pond No.: 4,904.10 10,241.00 cu. ft. 4,904.41 4,904.41 10,241.00 cu. ft.0.31 ft. 4,909.10 201,893 cu. ft. 4,908.43 Max. Elev. Min. Elev. cu. ft. acre ft cu. ft. acre ft 4,904.10 N/A 30,217 0.00 0.00 0.00 0.00 0.00 4,905.00 4,904.10 35,797 0.90 29,706.30 0.68 29,706.30 0.68 4,906.00 4,905.00 42,273 1.00 39,035.00 0.90 68,741.30 1.58 4,907.00 4,906.00 49,041 1.00 45,657.00 1.05 114,398.30 2.63 4,908.00 4,907.00 56,098 1.00 52,569.50 1.21 166,967.80 3.83 4,909.10 4,908.00 64,188 1.10 66,157.30 1.52 233,125.10 5.35 STAGE STORAGE CURVE Contour Contour Surface Area (ft2) Depth (ft) Incremental Volume Cummalitive Volume Pond Stage Storage Curve 1896-001 Fort Collins, CO B. Mathisen Elev at WQ Volume: Rudolph Farm May 10, 2023 Pond Outlet and Volume Data Outlet Elevation:Water Quality Volume: Elev at 100-yr Volume: Crest of Pond Elev.: Volume at Grate: Grate Elevation: Storage and Water Quality Pond 1 Project Number: Project Location: Calculations By:1 Water Quality Depth: 100-yr Volume: 1 Project: Calc. By: Date: 11.55 <-- INPUT from impervious calcs 49%<-- INPUT from impervious calcs 0.49 <-- CALCULATED 40 hours <-- from FCSM Figure 5.4-1 1.00 <-- from FCSM Figure 5.4-1 0.20 <-- FCSCM Equation 7-1 0.24 <-- FCSCM Equation 7-2 10,241 <-- Calculated from above 0.31 <-- INPUT from stage-storage table 0.95 <-- CALCULATED from FCSCM Equation 6-7 dia (in) =6/8 number of columns=2.00 number of rows =2.00 number of holes =4.00 Area Per Row =0.93 Total Outlet Area (in2) =1.86 <-- CALCULATED from total number of holes WQCV (ac-ft) = WQ Depth (ft) = Area Required Per Row, a (in2) = Circular Perforation Sizing WQCV (cu. ft.) = WQCV (watershed inches) = WATER QUALITY POND DESIGN CALCULATIONS Standard Water Quality Pond 1 Rudolph Farm B. Mathisen October 25, 2022 Required Storage & Outlet Works Basin Area (acres) = Basin Percent Imperviousness = Basin Imperviousness Ratio = Drain Time = Drain Time Coefficient = NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Project: Calc. By: Date: 14.57 <-- INPUT from impervious calcs & footprint of RG 80%<-- INPUT from impervious calcs 0.80 <-- CALCULATED 12 hours <-- from FCSCM Figure 5.4-1 0.80 <-- from FCSCM Figure 5.4-1 0.26 <-- FCSCM Equation 7-1 0.32 13,892 <-- Calculated from above WQCV (ac-ft) = WQCV (cu. ft.) = Basin Area (acres) = Basin Percent Imperviousness = Basin Imperviousness Ratio = Drain Time = Drain Time Coefficient = WQCV (watershed inches) = Required Storage & Outlet Works WATER QUALITY POND DESIGN CALCULATIONS Rain Garden 1 Rudolph Farm B. Mathisen May 10, 2023 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia =80.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100)i = 0.800 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.26 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area) Area = 634,729 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV =cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 =0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER =cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER =13,892 cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum)DWQCV =12 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 4.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin =10156 sq ft D) Actual Flat Surface Area AActual =15780 sq ft E) Area at Design Depth (Top Surface Area)ATop =23637 sq ft F) Rain Garden Total Volume VT=19,709 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided?1 B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y =ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 =cu ft iii) Orifice Diameter, 3/8" Minimum DO = in Design Procedure Form: Rain Garden (RG) Blaine Mathisen Northern Engineering May 10, 2023 Rudolph Farm Rain Garden 1 UD-BMP (Version 3.07, March 2018) Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO Raingarden 1.xlsm, RG 5/10/2023, 3:41 PM Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation A) Will the rain garden be irrigated? Notes: Design Procedure Form: Rain Garden (RG) Blaine Mathisen Northern Engineering May 10, 2023 Rudolph Farm Rain Garden 1 Choose One Choose One Choose One Sheet Flow- No Energy Dissipation Required Concentrated Flow- Energy Dissipation Provided Plantings Seed (Plan for frequent weed control) Sand Grown or Other High Infiltration Sod Choose One YES NO YES NO Raingarden 1.xlsm, RG 5/10/2023, 3:41 PM Forebay ID WQCV (cu. ft.) 1% WQCV (cu. ft.) DEPTH (in) Length (ft) Width (ft) Volume (cu. ft.)Notes RG 1 16,670 166.70 12 21 8 168 Design Point RG 1 RG 1.2 2,920 29.20 12 9.5 4 38 WQCV for RG1.2 was calculated by taking the weighted average from design points r12 and r13 (the areas going to this forebay) against the total area going to Rain Garden 1 (design point RG 1). Calculation is...((.59+1.96)/14.56)*16,670)=2,920 cu. ft. Refer to rational calcs and drainage exhibit for additinal clarification RG 2 24,577 245.77 12 21 12 252 Design Point RG 2 RG 3 - dp 4 8,634 86.34 12 22 4 88 Half of Rain Garden 3's volume. This is still conservative because Basin 10 will not be routed to this forebay. RG 3 - dp 5 8,634 86.34 12 22 4 88 Half of Rain Garden 3's volume. This is still conservative because Basin 10 will not be routed to this forebay. Forebay Summary