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Drainage Reports - 08/30/2018
City'of -Collins rov Plans ;Approved By "Date a . FINAL DRAINAGE REPORT Harmony Commons Subdivision Lot 5 Prepared for: Capital Real Estate, Inc. 50 South Sixth Street, Suite 1480 Minneapolis, MN 55402 (612)313-0126 Prepared by: Interwest Consulting Group 1218 West Ash, Suite A Windsor, Colorado 80550 (970)674-3300 May 31, 2018 Job Number 1339-178-00 INTERWEST M CONSULTING G R O U P May 31, 2018 Mr. Wes Lamarque City of Fort Collins Stormwater 700 Wood Street Fort Collins, CO 80522-0580 RE: Final Drainage Report for Harmony Commons Subdivision — Lot 5 Dear Wes, I am pleased to submit for your review and approval, this Final Drainage Report for the Harmony Commons Subdivision — Lot 5 development. 1 certify that this report for the drainage design was prepared in accordance with the criteria in the City of Fort Collins Storm Drainage Manual. I appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. Sincerely, Reviewed By: Erika Schneider, P.E. Colorado Professional Engineer No. 41777 121E WEST ASH, SUITE C WINDSOR, COLORADO 80550 TEL. 970.674.3300 • TAX. 970.674.3303 Michael Oberlander, P.E., LEED AP Colorado Professional Engineer No. 34288 TABLE OF CONTENTS TABLEOF CONTENTS............................................................................................................ iii ' 1. GENERAL LOCATION AND DESCRIPTION................................................................ 1 1.1 Location...........................................................................................................................1 1.2 Description of Property................................................................................................. 1 1.3 Floodplain Submittal Requirements............................................................................. 1 2. DRAINAGE BASINS AND SUB-BASINS.......................................................................... 2 2.1 Major Basin Description................................................................................................ 2 2.2 Sub -basin Description.................................................................................................... 2 3. DRAINAGE DESIGN CRITERIA...................................................................................... 2 3.1 Regulations......................................................................................................................2 3.2 Directly Connected Impervious Area (DCIA) Discussion .......................................... 2 3.3 Development Criteria Reference and Constraints...................................................... 4 3.4 Hydrological Criteria..................................................................................................... 4 3.5 Hydraulic Criteria.......................................................................................................... 5 3.6 Floodplain Regulations Compliance............................................................................. 5 3.7 Modifications of Criteria............................................................................................... 5 4. DRAINAGE FACILITY DESIGN....................................................................................... 5 ' 4.1 General Concept............................................................................................................. 5 4.2 Specific Details................................................................................................................ 5 ' 5. CONCLUSIONS....................................................................................................................7 5.1 Compliance with Standards.......................................................................................... 7 5.2 Drainage Concept........................................................................................................... 7 ' 6. REFERENCES...................................................................................................................... 8 ' APPENDIX VICINITY MAP AND DRAINAGE PLAN.............................................................................. A HYDROLOGIC COMPUTATIONS..........................................................................................B ' HYDRAULIC COMPUTATIONS..............................................................................................0 WATER QUALITY AND LID INFORMATION.................................................................... D EXCERPTS FROM REFERENCE REPORTS......................................................................... E 1. GENERAL LOCATION AND DESCRIPTION 1.1 Location The Harmony Commons Subdivision — Lot 5 is located in the Northwest Quarter of Section 4, Township 6 North, Range 68 West of the Sixth Principal Meridian, in the City of Fort Collins, Larimer County, Colorado. Please refer to the vicinity map in Appendix A. The project site is located at the northwest corner of Timberwood Drive and Lady Moon Drive. Lady Moon Drive bounds the property on the east, Lot 6 of Harmony Commons on the west and Lot 4 of Harmony Commons on the north and Timberwood Drive on the south. 1 1.2 Description of Property The property consists of about 1.85 acres of land and will consist of a new building, new parking and drive aisles. The site generally slopes in a westerly direction at approximately 0.5% to 1.0%. It was overlot graded with the development of Lots 3 and 4. The land is currently being used as overflow parking with a recycled asphalt surface. According to FEMA Panel 08069C0994F there are no mapped FEMA Floodways on this property. 1.3 Floodplain Submittal Requirements 1 Because the project is not within any FEMA or City of Fort Collins mapped floodway, a Floodplain Submittal is not required and a "City of Fort Collins Floodplain Review Checklist for 100% Submittals" has not been included with this report. 1 ' 2. DRAINAGE BASINS AND SUB -BASINS ' 2.1 Major Basin Description The proposed development lies within the McClellands Basin and McClellands Creek Master Drainage Plan. The overall development has been designed with a master plan by Stantec Consulting, Inc. and titled "Final Drainage and Erosion Control Study Harmony Technology Park Site Master Plan", dated May 19, 2008. The area was also designed with a drainage report by Interwest Consulting Group, Inc. and titled "Final Drainage Report Harmony Commons Subdivision", dated March 11, 2016 and approved by the City on May 16, 2016. 2.2 Sub -basin Description Historically, the site drained to the storm system in Lady Moon Drive and Rock Creek Drive and eventually reaches the Fossil Creek Reservoir Inlet Ditch (FCRID). With the Harmony Commons development, the majority of the site drains west to south to a new regional detention pond. 3. DRAINAGE DESIGN CRITERIA 3.1 Regulations ' This report was prepared to meet or exceed the "City of Fort Collins Storm Drainage Design Criteria Manual' specifications. Where applicable, the criteria established in the ' "Urban Storm Drainage Criteria Manual' (UDFCD), developed by the Denver Regional Council of Governments, has been used. ' 3.2 Directly Connected Impervious Area (DCIA) Discussion Urban Drainage and Flood Control District (UDFCD) recommends a Four Step Process for receiving water protection that focuses on reducing runoff volumes, treating the water quality capture volume (WQCV), stabilizing drainageways and implementing long-term source controls. The Four Step Process applies to the management of smaller, frequently occurring events. 2 Step 1: Employ Runoff Reduction Practices To reduce runoff peaks, volumes, and pollutant loads from urbanizing areas, implement Low Impact Development (LID) strategies, including Minimizing Directly Connected Impervious Areas (MDCIA). Runoff from the building's roof, parking lot and surrounding sidewalks shall drain directly into a sand filtration system thereby slowing runoff and also promoting infiltration Step 2: Implement BMPs that Provide a Water Quality Capture Volume with Slow Release Once runoff has been minimized, the remaining runoff shall be treated through the sand filtration system. The sand filtration system allows for settlement of sediments. Step 3: Stabilize Drainageways Natural Drainageways are subject to bed and bank erosion due to increases in frequency, duration, rate and volume of runoff during and following development. Because the site drains to the master planned regional water quality and detention pond, bank stabilization is unnecessary with this project. Step 4: Implement Site Specific and Other Source Control BMPs Proactively controlling pollutants at their source by preventing pollution rather than removing contaminants once they have entered the stormwater system or receiving waters is important when protecting storm systems and receiving waters. This can be accomplished through site specific needs such as construction site runoff control, post - construction runoff control and pollution prevention / good housekeeping. It will be the responsibility of the contractor to develop a procedural best management practice for the site. 3 3.3 Development Criteria Reference and Constraints ' The runoff from this site has been routed to conform to the requirements of the City Stormwater Department and the approved Harmony Technology and Harmony Commons ' drainage plans. Because water quality capture volume from this site will be provided for in the downstream regional detention and water quality pond 301, water quality facilities ' are not required for the site. However, City LID requirements are necessary therefore; additional water quality will be accomplished through the use of the sand filtration system ' that includes 1,204 cf of water quality capture volume. The impervious area for the site has also already been accounted for in Pond 301 and was assumed to have a C value of 0.80 and an impervious value of 80%. Please refer to supporting documentation in ' Appendix E. Runoff reduction practices (LID techniques) are also required. No less than seventy five percent of any newly developed or redeveloped area, and any modification on a previously developed area for which a construction permit is required under City codes and regulations, must be treated using one or a combination of LID techniques. The project adds 53,894 sf of new impervious area. Using the sand filtration LID technique, 41,735 sf of new impervious area (77%) will be treated which exceeds the 75% requirement. Please refer to Appendix D for LID calculations and information. 3.4 Hydrologic Criteria Runoff computations were prepared for the 10-year minor and 100-year major storm frequency utilizing the rational method. All hydrologic calculations associated with the basins are included in Appendix B of this report. Standard Form 8 (SF-8) provides time of concentration calculations for all sub - basins. Standard Form 9 (SF-9) provides a summary of the design flows for all Sub - basins and Design Points associated with this site. Water quality capture volume and detention has been provided for in the downstream regional detention and water quality pond 301. 4 3.5 Hydraulic Criteria All hydraulic calculations are presented in Appendix C of this report and are prepared in accordance with the City of Fort Collins Drainage Criteria. Hydraulic calculations include inlet capacity spreadsheets and StormCAD calculations. 3.6 Floodplain Regulations Compliance The project is not within any FEMA or City of Fort Collins mapped floodway; therefore, Floodplain Regulations Compliance is not required. 3.7 Modifications of Criteria There are no Modifications of Criteria for this development. 4. DRAINAGE FACILITY DESIGN 4.1 General Concept The majority of the proposed development will be collected and conveyed to the proposed storm drain system via the sand filtration system before being conveyed under Timberwood Drive to Pond 301. A small portion of the site (play area to the north of the building) will be collected in the existing storm system located in drive aisle to the north. 4.2 Specific Details A summary of the drainage patterns within each basin is provided in the following paragraphs. Please refer to Appendix A for the drainage plan. 5 PROPOSED DEVELOPMENT (LOT 5) Basin Al contains the roof of the daycare and is calculated to have a 10-year discharge of 1.3 cfs and a 100-year discharge of 2.8 cfs. Flows from Basin Al are captured by a proposed roof drain storm system that will discharge to the sand filtration system in basin B 1 and then to the existing system to the west of the development. This system releases into the existing double 5'x2' box culvert under Timberwood Drive. This culvert directs flow south to Pond 301. Basin A2 contains the play yard located to the west of the daycare and is calculated to have a 10-year discharge of 0.3 cfs and a 100-year discharge of 0.8 cfs. Flows from Basin A2 are captured by a proposed storm system under the play area that will discharge to the sand filtration system in basin B 1 and then to the existing system to the west of the development. This system releases into the existing double 5'x2' box culvert under Timberwood Drive. This culvert directs flow south to Pond 301. Basin B1 is calculated to have a 10-year discharge of 3.1 cfs and a 100-year discharge of 7.9 cfs. Basin B1 contains the parking lot, drive aisle and adjacent sidewalks. Flows from Basin B1 are captured by the sand filtration system via area inlets. The sand filtration system will incorporate 12" of flood control depth above the water quality capture volume where the 100-year flow will be detained and reduced to 5.7 cfs with an orifice plate on the 15" RCP discharge pipe. ' An underdrain system will release this flow from the sand filtration system into the ' proposed 15" RCP system that discharges to the existing storm system discussed above. Basin D3 is calculated to have a 10-year discharge of 0.3 cfs and a 100-year discharge of 0.7 cfs. This basin contains the sidewalk and southern half of the drive aisle located to the north of the proposed building. Flows from this area will drain to the existing 5' Type R inlet and storm system located at design point D3. This existing storm system releases into the existing double 5'x2' box culvert under Timberwood Drive. 2 Basin D4 is calculated to have a 10-year discharge of 0.3 cfs and a 100-year discharge of 0.8 cfs. This basin contains the play area to the north of the proposed building of Lot 5. Flows from this area will be collected in a 4 inch under drain system that will drain to the existing storm system located in the north drive aisle at design point D3. This existing storm system releases into the existing double 5'x2' box culvert under Timberwood Drive. The weighted average C value of the site is 0.75 which is below the Harmony Tech Park model assumption of 0.80; therefore, detention is not required on -site and is provided for in the regional Pond 301 located south of the site. Please refer to Appendix E for excerpts from the Harmony Tech Park design. i 5. CONCLUSIONS ' 5.1 Compliance with Standards ' All computations that have been completed within this report are in compliance with the City of Fort Collins Storm Drainage Design Criteria Manual. 5.2 Drainage Concept ' The proposed drainage concepts presented in this report and on the construction plans ' adequately provides for stormwater quantity and quality treatment of proposed impervious areas. Conveyance elements have been designed to pass required flows and to minimize future maintenance. If, at the time of construction, groundwater is encountered, a Colorado Department of Health Construction Dewatering Permit will be required. 7 6. REFERENCES r 1. Interwest Consulting Group, "Final Drainage Report Harmony Commons Subdivision', dated March 11, 2016. 2. City of Fort Collins, "Fort Collins Stormwater Criteria Manual Amendments to the Urban Drainage and Flood Control District Criteria Manual", adopted December 2011. 3. Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria Manual", Volumes 1 and 2, dated June 2001, and Volume 3 dated November 2010. 4. JR Engineering, "Final Drainage and Erosion Control Report Harmony Technology Park Second Filing", dated June 20, 2001. 5. Stantec Consulting, Inc., "Final Drainage and Erosion Control Study Harmony Technology Park Site Master Plan', dated May 19, 2008. 8 I 0 n n 0 APPENDIX A VICINITY MAP AND DRAINAGE PLAN A E HARMONY RD Y � w w O OJ 0 O Z _w w TIMBERWOOD DR o O r 0 a J SITE PRECISION DR ROCK CREEK DR HARMONY COMMONS, LOT 5 SCALE: t "=SOOT DRAINAGE SUMMARY TABLE W. n 71Rw1 Me. C(Im Clio) 6 IP 10 100) cgl im" Bua•bealn MiUl(3 FbMI Irl minl mMl Ida) Id>) AI Al 025 oV. 1,00 53 8.0 19 28 ROOF STORM SYSTEM TO SAND FILTER A2 A2 0.1s 0N5 058 8.7 73 0.3 0T PLAYGROUND STORM SYSTEM TO SAND FILTER B1 B' OM 01C. 095 5) 30 3.1 79 SANDFILTER m Cl e2 W 021 001 032 059 IN OS? 5.) 8.3 30 5o 0.8 03 20 07 EX S TYPE R SIMP DIET EXSTYPE R SUMP DIET rw Oa aT: 0a obe 8.3 0.3 03 e3 PLAYGROUND STORM SYSTEM TO EX S TYPE RMET PONDWRAMARYTABLE -�-� Im....elW DA..IIun TWIG $l Slo Sb a SIN e (0) Icub) (cu4) IW4 TOP SAND FILTER 11.0 11.5 480 480 WO OVERFLOW12.0 E38W 927 0 14D7 12.5 1158 lies 2575 FLOOD 13.0 1393 2W2 39a 13.s 1e63 4215 U21 SPILLOVERWALK 13.7 74D 4954 6361 I LD VOLUME REQUIRED • 1,2D4 cull .._... .. _._ . __ LID .DEIENIION VCLLWE PROVIDED •. VOIA.ME REIXIIRED • __. _.1,407 3545 cub_..__ cub -- ----- OElEN110N - -�OIOU VOLLME PROVIDED • RELEASE RATE - _ 2,502 - 6.7 cull cls �f LOTS . A912=-�,� f I q/' f 4.. 1u I -T n R.RE% � 1� 217 a � !I 9 � QN WALL AT WADE �1 I C LOT 8 / 001101 N9016 M TO 40MO (q I .'.:1 ' • .e. I I �� k , 0.10 D.BC F AREA NET I LOTS I 0 , ! 20 10 O 20 40 FF=4916.5 i SCALE: r- 20' DEVELOPER'S COMPLETED II OF THE FIRST ------ -- ---------________ \ _ _ — k I 1 LEGEND 'XXXX- EXISTINGMINORCONTOUR 'RXYX� E STINGMA RCON70UR PROPOSEDMINOROONTOUR PROPOSEDMAIORCONTOUR PROPOSED DIRECNON OF OVERLAND FLOW FASTING DRAINAGE BASIN DIVIDE UNE A FA STING DRAINAGE BASIN ID MINOR STORM RUNOFF COEFFICIENT DRAINAGE BASIN AREA. ACRES PROPOSI�DDRAIBASINDIVIDE LINAGE A PROPOSEDDRMNAGEBAMNID aj MINOR STORM RUNOFF COEFFICIENT DRAINAGE BASIN ARE0. ACRES QDESIGN POINT O m a U Z w WLOID t NON ID O ILL Z m O W W f m W ~�~ T tiJ J N i — W Sa to haw IL a NW0 t Iz= IL U In 0 If) I A V 111A 1. NVIV Rr/IIN (3 CENTER OF COLORADO o a� 2 811 m u 6 f,6L1 2 2-SRIESS DAYS N ADVANCE w WI0 BEFORE YON DIG E. OR EXCAVATE N $ W W FOR TINE MARKNG OF UNDERGROUND q Z ER y MDIBUTILITIES 0 u F a b W CITY OF FORT COLLINS. COLORADO O O t=) UTILITY PLAN APPROVAL R[QA I' APPROVED: siCA CITY [NQIEERR DATE bn CHECKED BY: 34m WRIER • WASTEWER ATUR1O DATE CHECKED BY:•�' ` STMWAUR UWTY DATE FOVAL CHECKED BY: TARNS • REQ¢AR011 DALE PROD. 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N 0 0 0 0 0 0 LL LL O Z a z m = m Q QO] aN000 U y W 2 C �+ c .� N 'moo d co c0 .0 0 C n + o_ m� za U a LL n 0 ._ N O U 0 LL O o U m E w O` N N L N N C cap l9 f0 � c6 N N U N V N _N O C C y 0, N _ Co N C N C ca II II II ` II (3 U U .° Q n 0 0 CD c S Cl) 0 O U 0 a� m c LL ^ U. O� Z r N m V Q o W O a T G W O� = O W U J O o Q— Z p > A Q V rn v 0 E E 0 U T 0 O 000 O M O M rn n U � y � F O E"wa U O F a u Q Y S Q LU W R 0 o w co cornornco O N O r N 0 0 Q C7 O f O O N U ♦Y d W C } E m C ♦r O N O w o a Q U O y OD CO 0) O Il c0 U N O fn N O O Q t in in LO LO CM_ Onrnrnmrn O C O m 0 0 0 m E ui ui ui ui co 0coinonrn U ONrnoco(o U o o o 0 U Q ttt N— cco N O 7 O O O O O O LL LL O O N Q Q Q m m ❑ ❑ F ❑ U W cc m Cli Cl) 0 ao -0 Q U II 0 in n m 0 o (D .F T p d cm OD 0 OD LL n p •- N C O U 0 0 LL O U O w N L_ d U ` L U r lC co w c fu 1 U N �C cu O c�0 N =3 C Q. L p II II ` II 0C) Q N X a LL U) H 0 O LL U LL OD O7) 4 of exceedance every year). In some instances the 100-year storm routing of runoff will not be the same as that for the 2-year storm. (3) A new Section 1.2 is added, to read as follows: 1.2 Minor (2-Year) Storm Provisions The objectives of such drainage system planning are to minimize inconvenience, to protect against recurring minor damage and to reduce maintenance costs in order to create an orderly drainage system at a reasonable cost. The 2- year storm drainage system may include such facilities as curb and gutter, storm sewer, open channels, drainageways, ponds, rivers, streams, and detention facilities. (4) Anew Section 1.3 is added, to read as follows: 1.3 Manor (100-Year) Storm Provisions The objectives of the 100-year storm drainage system planning are to eliminate substantial loss of life or property damage. Major drainage systems may include storm sewers, open channels, drainageways, ponds, rivers, streams, and detention facilities. The correlation between the minor and major storm system must be analyzed to ensure that a well coordinated drainage system is designed and constructed. (5) Section 2.0 is deleted in its entirety. (6) Section 2.1 is deleted in its entirety. (7) Section 2.2 is deleted in its entirety. (8) Section 3.0 is deleted in its entirety. (9) Section 3.1 is deleted in its entirety. (10) Section 3.2 is deleted in its entirety. (11) Section 4.0 is amended to read as follows: 4.0 Intensity -Duration -Frequency Curves for Rational Method The one -hour rainfall Intensity -Duration -Frequency tables for use with the Rational Method of runoff analysis are provided in Table RA-7 and in Table RA-8. Table RA-7 City of Fort Collins Rainfall Intensity -Duration -Frequency Table for Use With the Rational Method (5 minutes to 30 minutes) Duration (min) 2-Year Intensity (in/hr) 10- Year Intensity rn/hr) 100-Year Intensity rn/hr) 5 2.85 4.87 9.95 6 2.67 4.56 9.31 7 2.52 4.31 8.8 8 2A 4.1 8.38 9 2.3 3.93 8.03 10 2.21 3.78 7.72 11 2.13 3.63 7.42 12 2.05 3.5 7.16 13 1.98 3.39 6.92 14 1.92 3.29 6.71 15 1 1.87 3.19 6.52 16 1.81 3.08 6.3 17 1.75 2.99 6.1 18 1.7 2.9 5.92 19 1.65 2.82 5.75 20 1.61 2.74 5.6 21 1.56 2.67 5.46 22 1.53 2.61 5.32 23 23 1.49 2.55 52 24 1.46 2.49 5.09 25 1.43 2.44 4.98 26 1.4 2.39 4.87 27 1.37 2.34 4.78 28 1.34 1 2.29 1 4.69 29 1.32 2.25 4.6 30 1.3 2.21 4.52 Table RA-8 City of Fort Collins Rainfall Intensity -Duration -Frequency Table for Use with the Rational Method (31 minutes to 60 minutes) Duration (min) 2-Year Intensity (in/hr) 10-Year Intensity (in/hr) 100-Year Intensity (b✓hr) 31 1.27 2.16 4.42 32 124 2.12 4.33 33 1.22 2.08 4.24 34 1.19 2.04 4.16 35 1.17 2.0 4.08 36 . 1.15 1.96 4.01 37 1.16 1.93 3.93 38 1.11 1.89 3.87 39 1.09 1.86 3.8 40 1.07 1.83 3.74 41 1.05 1.8 3.68 42 1.04 1.77 3.62 43 1.02 1.74 3.56 44 1.01 1.72 3.51 45 .099 1.69 3.46 46 0.98 1.67 3AI 47 1 0.96 1.64 3.36 48 0.95 1.62 3.31 49 0.94 1.6 327 50 0.92 1.58 3.23 51 0.91 1.56 3.18 52 0.9 1.54 3.14 53 0.89 1.52 3.1 54 0.88 1.5 3.07 55 0.87 1.48 3.03 56 0.86 1.47 2.99 57 0.85 1.45 12.96 58 0.84 1.43 2.96 59 0.83 1.42 2.89 60 0.82 1.4 2.86 (12) A new Section 4.1 is added, to read as follows: 4.1 Intensity -Duration -Frequency Curves for SWMM: The hyetograph input option must be selected when creating SWMM input files. Hyetographs for the 2-, 5-, 10-, 25-, 50- and 100-year City of Fort Collins rainfall events are provided in Table RA-9. 24 APPENDIX C HYDRAULIC CALCULATIONS C Interwest Consulting Group 1218 W. Ash, Suite C Windsor, CO 80550 Inlet Flow Calculation for Area Inlet Project: Harmony Commons Lot 5 1 Job Number: 1254-045-01 Calculations by: es Date : 1 /25/2017 1 Objective: to find the number of grates required for area inlets in grassy areas WSEL ' Geometry at inlet Grate Open Area and information: Square Feet Open (A): 2.66 sf Deeter Foundry Grate 3435 ' Reduction Factor (F): 50% Grate Flow: Use the orifice equation Q; = C*A*SQRT(2*g*H) to find the ideal inlet capacity.* 'See Hydraulic Design Handbook by McGraw-Hill for verificaiton of equation use and C value C = Orifice discharge coefficient= 0.67 A = Orifice area (ft) - open area of grate g = gravitational constant = 32.2 ft/s2 H = head on grate centroid, ponding depth (feet) Then multiply by the reduction factor for the allowable capacity. ' OG = Qi * (1-F) DP B1 Q = 4 cfs Q100/2 (Two Inlets, split basin) H = 0.5 It A= 2.66 ftZ Qi = C*A*SQRT(2*g*H) 10.11 cfs Qo= Qi*F _ _ = 5.06 cfs OK Pagel 1 1EDeeterFOUNDRY 1 Square & Rectangular Frames & Grates 1 3203-3451 1 SQUARE AND RECTANGULAR DRAINAGE GRATES Heavy Duty , 1 1. When ordering specify whether grate only is required or whether grate with frame is required. 2. Note asterisk where angle frames also available. H —I --� 1 1 1 �o - �o 0000a ��oo�o�o 0 o aao 0 0 0 a o aao t� o DDDDD aoa sAne A sb%a sw c S" D 1 SQUARE HEAVY DUTY 1 catalog No. A B G H Style Open Area Sq. In. ' 3203 18x18 1112 1 x71/16 1 A 113 1 3209 21 3/4 x 21 3/4 11 /2 1 1 /2 x 19 1 B 228 3224 26 x 26 11/4 1 x 4 7/8 1 A 234 1 3224-A 271/4 X271/4 2 1X5 1 A 240 3226 273/4 x 273/4 2 21 /2 x 2 1 /2 1318 - 225 1 3227 27 x 27 2 21 /2 x 5 118 1 B 359 3227-A 29 x 29 17/16 13/8 x 8 1 /8 11 /8 A 382 1 3233 30 x 30 13/4 2 3/8 x 113/4 1112 A 390 3237 34 x 34 21/8 2 x 141 /2 11 /8 A 580 3450 281/4x281/4 11/4 1 x121/4 11/4 A 294 1 RECTANGULAR HEAVY DUTY 1 ' Catalog No. A B G H Style Open Area Sq. In. 3167 14 1/2 x 27 13/8 3/8 x 5 1/2 1 P 95 ' 3297 10 x 17 1/2 13/4 13/4 x 3 1/2 1 A 74 3306 10 1 /4 x 24 15/8 11/2 x 3 1 /8 1 A 84 ' 3309 10 1 /4 x 33 1 1/2 1 5/8 x 7 3/4 11/4 B 139 3310 111/2 x24 11/2 1 x6 1 C 90 ' 3311 11 1/2 x 23 7 /8 1 1/2 x 4 3/4 5/8 C 90 3321 13 x 24 13/8 1 x 5 1 A 110 ' 3336 14 x 24 2 1 x 5 1/2 1 A 99 3339 14 x 24 2 11/16 x 5 1/2 1 A 129 3345 14 1/2 x 28 2 2114 x 4 1 C 180 ' 3351 15 x 27 2 15/8 x 6 1 A 195 ' 3354 151/2 x285/8 2 21/2 x81/16 11/8 C 242 ' ' 3363 16 x 24 13/4 19/16 x 6 1/2 1 A 183 ' 3381 18 x 24 3/4 2 x 4 1 A 168 ' ' 3384 18 x 24 11/2 11 /8 x 10 11/4 A 158 3387 18 x 30 21/2 11/2 x 13 1/4 7/8 C 278 ' 3390 18 x 36 2 13/4 x 6 1/2 11 /8 C 228 3392 191/2x211/2 2 11/2x8 1 A 192 ' 3393 191/2 x24 11/2 11/2 x8 1 A 216 ' ' 3400 20 1/2 x 36 2 21 /8 x 7 7/16 1 C 379 ' 3401 21 x 341 /4 2 2 x 8 5/8 1 A 379 3403 22 x 37 2 2 x 8 5/8 1 C 448 ' 3406 22 112 x28 1/2 11/2 11/4 x 17 1 B 234 ' 3421 23 3/4 x 35 3/4 2 1 x 33 3/4 1 D 371 ' 3431 24 x 28 2 13/4 x 20 3/8 13/8 C 285 3433 24x30 11/2 11/2 x41/4 11/4 C 255 ' ' 3434 24 x 30 21 /4 1 1/2 x 6 1 C 243 ' 3435 24 x 33 2 115/16 x 14 1/8 11/4 A 383 ' 3437 24 x 36 2 2118 x 4 1/2 11 /8 C 382 3438 24 x 36 13/4 1 x 9 7/8 1 B 336 ' 3439 24 x 38 13/4 15/8 x 8 13/16 C 416 0 2018 Deeter Foundry, all rights reserved E c CE iv Vl Z ID O I-t n m Ol Ol N Ill 00 N Ol N IT m V' ID N M M Vl 111 m .+ .-i I\ ✓1 O O N ID tt V m M 00 ti ID N M M In Ih N m 00 .-+ .+ M 00 N V ID N O In r, n. .-i !V N O O O1 O -4 .+ .+ N N .-I -4 ti N N N N M N N N f\ m V M N 1l1 m N m ID V1 Ol Ol Ifl M Vl ID m m 'T V1 n m Ol O .-+ Ol O M n n m .-i n Ol '7 ON M n. 01 N n m m m .-� .-� m Ill .-� m Nr f� m n Ill n n N 0 0 .-+ QI 6 .-+ .-+ .-+ .-+ .-+ N N N N N rV N M rV N N 00 It m O m V' 7 N N M M v m m O m O O O m M M M Ill '+ ID ID N Ol m M N r• n m m n .+ N IT N m V N I\ Ol O O m O .4 .4 .4 .} .-i N N -4 rV N N N N N N N m y ID m 10 m ID n to Ir m ID N Ill m Vl N N m Nr N Ol Ill m IT N O O O o m IO IT t\ v ID Ol m O N Ol �t h n m m .-� .+ 111 Ill O— M Ill m ID m N I\ Ol O Ol cD fV N .i .-4 N N N N N M N N N . .4 .d .ti .-1 . .-1 .1 . .d .ti . 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CO CRETE BAIO■.11 CLMe [X te' RW e- ■N T0P�K11.00 S-3O8 I L"LF OFY7N NM.A00e. EX 1 ]0'XB• BAIT." WASHED 5-1.238 CONCRETE 70P-4110II.00� NWAR06B0 BAMM CYRB GPi11F PLATE N-,2 i ETA 1za21.e FOB Ia W FLoao CONTROL �IX e• SS WPO W00 N)F00 ,D120 10F10 t0a00 IW00 1N00 1N20 w 11ae0 12.00 INW 12440 I i t I II 11110 I--- -- _- -------L_1I II II 0 )Y➢CRMET OJ_ CX Fw-491JT7 a>. IAX E((.X9gA 4> A ORLL 5 > CX 4' / S1N NN CX Nw-19r32 CX a- wP (C)-490 w A EX 6' WV EW)-49GY11>M Z0 CX 6• wV /Nf-49R2 - - - - - - - - - - - - - - �__ - -- IL __----__-- - --- ----------- 20 10 0 20 HORIZONTAL SCALE 20' VERTICAL SCALE'. I"- 4' 40 �I I I CALL UTILITY NOTIFICATION E I CENTER OF COLORADO 811 I QML 2-BU91AM DAYS NI ADVANCE I BEFORE YDU M. ORATE. M EXCAVATE fGR 111E YARKNG DF UNDENGROU1m MEMBER UMTES I NOTES: 1 ALL STORM SEWER ANDWATERCONSTRUCTION.AS WELL AS POWER AND OTHER 'DRY" lm WN INSTALUllONS. SHALL CONFORM 10 THE I CITY OF FORT GOWNS STANDARDS AND S'ECIFICATIWiSCURRENi Ar 111E DATE OF APRgVAL OF THE PUNS BY THE LGCAL ENGINEER 2. STORM SEWER RPE SHALL BE RCP Cq SIXt 35 PVC WfIH WATER I TMiHIJO1NT5 AS SPECIFlED ON THE PLAN ALL STORM SEW ER SHALL I BE INSPECTED BV THE CRY OF FORTCOLLNTS I 3. LENGTH OF %PE IS MEASURED FROM CENTER OF SilAlC1UFE TO CENTER OF STRU(:TURE I 4. NORTHING HING AND EASi1NG5 AND STATIONING$ ARE CENTER OF I STRUCTURE UNLESS OTHERWCSE NOIID. 1I 6. ANY DAMAGED CURB. GUTI£R AND 90EWALK EXISNNG PRNM TO I CONSHS, DEW. DAMAG CX4 R IDEWALK ECURBSAND GUTTERS DESN OTHIS PMAGED OR REMWED W E TO CONSTRUCTION OF OT NSf7TANO. SHALL THE CI VELO OR REXPE NSE TO CRY OF FORT COWNS STANDARDS ATTHE DEVELOPER'S EXPENSE I PRIOR TO THE ACCEPTANCE OF GOMFLETEDNIPROV OF OR roR I PRTO THE ISSUANCE OF THE FIRSTCERRFICATE OF OCCUPANCY Iz Eli I I� o 10 17 I>. 113 IQ I �I I I I 1 I 1 I I I I I I I I I I I 0) a (.) WZ F NO 'D It F n N N L, Zm W W Wpm � J N J N LL W S 0 K I D w 4 <�WO t a:Z = � on(. U U) O N 8 J II ZZ Yy m \1 z W yu�ji Y£1 ,C1 w ( CITY OF FORT COLLINS COLORADO ET YI S = U NOTE: ALL STORM SEWERS ARE PRIVATELY OWNED AND MAINTAINED UTILITY PLAN APPROVAL yo RE01s APPROVED: �!y CIDATE G CHECKED BY: 3420 MA1ER A WASTEWATER YTIUTY DATE CHECKED BY: ` SlORY11A1E11 UTILITYDALE FOiAL CHECKED BY: PARKS R RECREATNII DATE PROJ. NO. 133W I75 CHECKED BY: RIAii1C ENGrcEx DATE 10 CHECKED BY: EMxRwERTu PLIMCR DATE AS -BUILT SURVEY LOTS 3,4 AND 5 OF HARMONY COMMONS, LOCATED IN THE NORTHWEST QUARTER OF SECTION 4, TOWNSHIP 6 NORTH, RANGE 68 WEST OF THE 6TH PRINCIPLE MERIDIAN, CITY OF FORT COLLINS, COUNTY OF LARIMER, STATE OF COLORADO W RM • w,].M 1 W • 1af0,1 W IPM . m1 aJ L+u.:nunuPf +f.. maol � I N. • +IBBH RAN SnIICTVRL TOP . m\. BB-T / INS . +EW BS 1 R. [ • +ae.w SANITARY AND STORI.1 DET nlL — A0, 0 40' 80' N ENS LEEK WATER .AL r Ff-t MYDR:NT (� S.WIT.RY Mf NNOLE CLEAN OUT G AREA DRAIN ® STCRMDRAIN MANHOLE n LIGHT POLE ..,CMTP'� al.Nlf.�'fYl C Pp FyfNLyM1�M1L�PB5.e uT .nl PMu, R M�lypiM�vw P: FIWW, f945M11Nf� �YPIMIVLNif'tlWID SW�:\ • YMpJ9gyPN IROIE55M1Ywt LwD SM.:YpI ue NOTICE ACCORDING TO COLCRADO LFW YOU Mv'T COMMENCE ANY LEGAL ACTION BASED UFJN ANY C:FECTS IN THIS CONDOMINIUM MAP W1TMN THFEE YEARS ..FTER Yf'U FIRST DSCC •ER SUCH DEFECT IN NO E'.YNT, MAY ANY ACTION BASED U" ANY DEFECT IN THIS ' UR,2Y BE CCF.WIENCED MORE THAN TEN YEARS AFTER THE DATE OF THE CERTWIC.TION SHOWN HEPEON. AS -BUILT ELNAT AAL "W AN A5-BUNT SURxY M T\R WIT PRETORM ON X7MR I+, "Id �jy� www.WashbumSuFveying.com ` Washburn 402$ Automation Wa>• Suite C4 LAND SURVEYING FDEI CCilinS, CO 80525 970-232-045 SKIM 1 Pf 1 PMIIHI I: 20]bOM DMB: MmJI 21. aPq SnM: i ^SB' Tn :CDR e u u u 1 APPENDIX D WATER QUALITY AND LID INFORMATION co G TV NdIN _�11 r�!-,� �q.■�r,���!� ��_; /ems u� is I, .i ------------------=-------------------- TIMBERWOOD DRIVE ---------- - ' On -She Tregernent by OD Requirement New Impervious Area S3,894 am/sq. ft. Required Minimum Impervious Area to be Treated 4,421 acre/sq. ft. Pavement Area Treated by LID Treatment (Sand Filte r) 26,017 acre/sq. ft. Other impervious Area TreatedLID Treatment Sand Filter 15718 ane s .ft. Total Impervious Area Treated 41,738 acre/sq. ft. ACual %OmSite Treated by LID A % LEGEND ` PAVEMENT AREA TREATED BY LID OTHER IMPERVIOUS AREA TREATED BY LID 60 30 0 60 120 SCALE. I _ HARMONY COMMONS LOT 5 LID EXHIBIT LID Table 7S% On -Site Treatment by LID Requirement New Impervious Area 53,894 acre/sq. ft. Required Minimum Impervious Area to be Treated 40,421 acre/sq. ft. Pavement Area Treated by LID Treatment (Sand Filter) 26,017 acre/sq. ft. Other Impervious Area Treatedby LID Treatment (Sand Filter) 15,718 acre/sq. ft. Total Impervious Area Treated 41,735 acre/sq.ft. Actual % On -Site Treated by LID 77 % II Design Procedure Form: Sand Filter (SF) II ' Sheet 1 of 2 Designer: MPO Company: Interwest Consulting Group Date: April 12, 2018 ' Project: Harmony Commons, Lot 5 Location: Harmony and Lady Moon I. Basin Storage Volume A) Effective Imperviousness of Tributary Area. I, i 73.0 (1009/6 it all paved and rooted areas upstream of sand filter) B) Tributary Area's Imperviousness Ratio (i - 1./100) = 0.730 C) Water Quality Capture Volume (WCCV) Based on 12-hour Drain Time WOCV = 0.26 watershed inches WOCV. 0.9' (0.91' i'- 1.19 - i?+ 0.78. 1) D) Contributing Watershed Area (including sandfilter area) Area = 55.490 sq it E) Water Quality Capture Volume (WOCV) Design Volume Vwocv = 1.204 Cu fl Vwocv - WQCV / 12' Area F) For Watersheds Outside of the Denver Region, Depth of dill = in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, Vwocv OTHEH - CU a Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WOCV) Design Volume Vwocv usra - Cu If (Only if a different WOCV Design Volume is desired) 2. Basin Geometry A) WOCV Depth Dwocv = 1.0 It B) Sand Filter Side Slopes (Horizontal distance per unit vertical, Z = 20.00 ft / ff 4:1 or flatter preferred). Use'0' tt sand filter has vertical walls, C) Mimimum Fitter Area (Flat Surface Area) AM,,, = 268 sq ft D) Actual Filter Area A,,,, , = 390 sq h E) Volume Provided V, = 1407 CU ft Choose One 3. Fitter Material Q 18" CDOT Class C Filter Material Q Other (Explain): 4. Untlerdrain System A) Are underdrains provided'r ff100se one ® YES ONO B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage Y = 3.3 ft Volume to the Center of the Orifice City of Fort Collins does ii) Volume to Drain in 12 Hours vu,'` 1,204 cu If not require an orifice for iii) Orifice Diameter. 3/8' Minimum D„ = 11 / 16 in Sand Filters. 1 4-10-18 SF UDFCD.xlsm, SF 4/12/2018, 9:02 AM Design Procedure Form: Sand Filter (SF) sheet 2 of 2 Designer: MPO Company: Interwest Consulting Group Date: April 12. 2018 Project: Harmony Commons. Lot 5 Location: Harmony and Lady Moon 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? Choose one Q YES Q NO 6 7. Inlet / Outlet Works A) Describe the type of energy dissipation at inlet points and means of conveying flows in excess of the WOCV through the outlet Notes: 1 4-10-18 SF UDFCD.xlsm, SF 4/12/2018, 9:02 AM J FLOW REDUCTION CALCULATIONS BASED ON PAVER VOLUME Rational Volumetric (FAA) Method OVERALL 100-Year Event 9.3 cis Masai on actual release of LOCATION: HC Lot 5 Basin Al, A2 AND III basin A, B1 and D4 (8.1 cis) from PROJECT NO: 1339-179.00 'Final Drainage Report Harmony COMPUTATIONS BY: es Commons Subdlv4ion'. dated 3-11-16 DATE: 4/9F2018 by Infervest Consulling Group minus Lot basin D4(0.8 cis)divened north Eouations: Area lrlb. to RG . 55490 at Developed flow = Oo = CIA C (100) - 0.95 Vol. In . Vi - T C IA -TO, Developed C A . 52716 at Vol. Out - Vo -K On T Release rate, On = 7.3 efa' storage = S - Vi- Vo K - 0.9 Rainfall intensity from City of Fort Collins IDF Curve with (3.67') rainfall Storm Rainfall Oo Vol. In Vol. Out Storage Duration, T min Intensity, I inif (Ma) Vi (ft) Vo (to) S (ft) 5 9.95 12.0 3612 1971 1641 6 9.31 11.3 4056 2365 1691 7 8.80 10.6 4473 2759 1713 8 8.38 10.1 4868 3154 1714 9 8.03 9.7 5248 3548 1700 10 7.72 9.3 5606 3942 1664 11 7.42 9.0 5927 4336 1590 12 7.16 8.7 6239 4730 1508 13 6.92 8.4 6532 5125 1407 14 6.71 8.1 6821 5519 13D2 15 652 7.9 7101 5913 1188 16 6.30 7.6 7319 6307 1012 17 6.10 7.4 7530 6701 828 18 5.92 7.2 7737 7096 642 19 5.75 7.0 7933 7490 443 20 1 5.60 6.8 1 8132 7884 1 248 21 5.46 6.6 8326 $278 47 22 5.32 6.4 8498 8672 -174 23 5.20 6.3 8684 9067 -382 24 5.09 6.2 8670 9461 -591 25 4.98 6.0 9040 9855 -815 26 4.87 5.9 9194 10249 -1055 27 4.78 5.8 9371 10643 -1272 28 4.69 5.7 9535 1103E -1502 29 4.60 5.6 9686 11432 -1746 30 4.52 5.5 9846 11826 .1980 31 4.42 5.3 9949 12220 -2271 32 4.33 5.2 1OD61 12614 -2553 33 4.24 5.1 10160 13009 -2849 34 4A6 5.0 10270 13403 -3133 35 4.08 4.9 10369 13797 -3428 36 4.01 4.9 10482 14191 -3709 37 3.93 4.8 10556 14585 .4027 38 3.87 4.7 10678 14980 -4301 39 3.80 4.6 10761 15374 -4613 40 3.74 4.5 1Dam 15768 4905 41 3.68 4.5 10956 16162 -5207 42 3.62 4.4 11040 16556 -5517 43 3.56 4.3 11115 16951 -5835 44 3.51 4.2 11214 17345 -6131 45 3.46 4.2 11306 M39 -6433 46 3.41 4.1 11390 18133 -6743 47 3.36 4.1 11467 18527 -7D61 48 3.31 4.0 11536 18922 .7385 49 327 4.0 11634 19316 -7681 50 3.23 3.9 11727 19710 -7983 51 3.18 3.8 11776 20104 -8328 52 3.14 3.8 11856 20498 -8642 63 3.10 3.8 11930 20893 -8963 54 3.07 3.7 12037 21287 .9249 55 3.03 3.7 12101 21681 -9580 56 2.99 3.6 12158 22075 -9917 57 2.96 3.6 12251 22469 -10218 58 2.96 3.6 12466 22864 1 -10398 59 2.89 3.5 12381 23256 -10877 60 1 2.86 3.5 12460 23652 -11192 Storage Volume for Design If 1714 fta 1 4-9-18 FAA POND SF FLOW REDUCTION 1 FT DEEP.:Is,LOT 5 MAX RELEASE RATE 4) cm cc L. O F+ N lC 'O c O a a 00 -. cq c O ° N roo V C1 W O a O L. >. z o° zz¢ 0 U w a o°rx0Q .a Q. U A (� m=00 O n LO Co T T +-� f6 O I, CD N (D O U co cm CO fn W � v c O N C C� n w a) CD O w � y 0 N i 7 c O 7 U D O a) N 0) U M CD o aa) o m _ 4) wca c — Q CD E = a)m CLds Q Q N O f1'C H U fa fa N + > O m N 7 Q „ „ „ a m a>-0Q v N a) rn ~ T II CDO 1 m > 3 a O I,INIcIa) NMM M.M. Y. u�lolfnlolfnll� T NN coo co T T T T T T cr 1 w o LL LL CC O O Z o o a: LU 0 O IL 3 O O J LL d (n w w w w U U U U U n N 4 Lq In r r N N 0000w W W W W ,. cc O LE O Q 5 > Z:) > 0000w ,.,_,¢worm Eraoro_Q w W w w J g222w i J J J Q o o o OO ozz0 �::i00 z z w w 00 FLOW REDUCTION CALCULATIONS BASED ON PAVER VOLUME Rational Volumetric (FAA) Method OVERALL 10D-Year Event LOCATION: HC Lot 5 Basin At, A2 AND Bl PROJECT NO: 1339-178.00 COMPUTATIONS BY: es DATE: 4/9/2018 Ecfuations: Area Ind. to RG = 55490 sf Developed flow = 00 = CIA C (100) = 0.95 Vol. In = Vi = T C I A = T On Developed C A = 52716 sf Vol. Out = Vo =K 0Po T Release rate, Ovo = 5.7 cis storage = S = Vi- Vo K = 0.9 Rainfall intensity from City of Fort Collins OF Curve with (3.67) rainfall Storm Rainfall OD Vol. In Vol. Out Storage Duration, T (min) Intensity, I (in/hr) (cfs) Vi (ft') Vo (tt') S (tt') 5 9.95 12.0 3612 1539 2073 6 9.31 11.3 4056 1847 2209 7 8.80 10.6 4473 2155 2318 8 8.38 10.1 4868 2462 2405 9 8.03 9.7 5248 2770 2477 10 7.72 9.3 5606 3078 2528 11 7.42 9.0 5927 3386 2541 12 7.16 8.7 6239 3694 2545 13 6.92 8.4 6532 4001 2531 14 6.71 8.1 6821 4309 2512 15 6.52 7.9 7101 4617 2484 16 6.30 7.6 7319 4925 2394 17 6.10 7.4 7530 5233 2297 18 5.92 7.2 7737 5540 2197 19 5.75 7.0 7933 5848 2085 20 1 5.60 6.8 1 8132 6156 1 1976 21 5.46 6.6 8326 6464 1862 22 5.32 6.4 8498 6772 1727 23 5.20 6.3 8684 7079 1605 24 5.09 6.2 8870 7387 1483 25 4.98 6.0 9040 7695 1345 26 4.87 5.9 9194 8003 1191 27 4.78 5.8 9371 8311 1061 28 4.69 5.7 9535 8618 917 29 4.60 5.6 9686 8926 760 30 1 4.52 5.5 1 9846 9234 1 612 31 4A2 5.3 9949 9542 407 32 4.33 5.2 10061 9850 211 33 4.24 5.1 10160 10157 2 34 4.16 5.0 10270 10465 -195 35 4.08 4.9 10369 10773 -404 36 4.01 4.9 10482 11081 -599 37 3.93 4.8 10558 11389 -830 38 3.87 4.7 10678 11696 -1018 39 3.80 4.6 10761 12004 -1243 40 3.74 4.5 10863 12312 -1449 41 3.68 4.5 10956 12620 1 -1664 42 3.62 4.4 11040 12928 -1888 43 3.56 4.3 11115 13235 -2120 44 3.51 4.2 11214 13543 -2329 45 3.46 4.2 11306 13851 -2545 46 3.41 4.1 11390 14159 -2769 47 3.36 4.1 11467 14467 -3000 48 3.31 4.0 11536 14774 -3238 49 3.27 4.0 11634 15082 -3448 50 323 3.9 11727 15390 -3663 51 3.18 3.8 11776 15698 -3922 52 3.14 3.8 11856 16006 -4150 53 3.10 3.8 11930 16313 -4383 54 3.07 3.7 12037 16621 -4584 55 3.03 3.7 12101 16929 -4828 56 2.99 3.6 12158 17237 .5079 57 2.96 3.6 12251 17545 -52E 58 2.96 3.6 12466 17852 -5387 59 2.89 3.5 12381 18160 -5779 60 2.86 3.5 12460 18468 -6008 Storage Volume for Design 1 2545 h' 1 4-9-18 FAA POND SF FLOW REDUCTION 1FT DEEP.zIs,LOT 5 MAX STORAGE VOL ' BASIN 131 100-yr Event, Outlet Sizing LOCATION: HARMONY COMMONS, LOT 5 ' PROJECT NO: 1339-178-00 COMPUTATIONS BY: es SUBMITTED BY: INTERWEST CONSULTING GROUP tDATE: 4/10/2018 Submerged Orifice Outlet: ' release rate is described by the orifice equation, Qo = COAO sqrt( 2g(h-E,)) where Q,, = orifice ouff low (cfs) ' Co = orifice discharge coefficient g = gravitational acceleration = 32.20 ft/s Ao = effective area of the orifice (W) ' Eo = greater of geometric center elevation of the orifice or d/s HGL (ft) h = water surface elevation (ft) Qo = 5.70 cfs outlet pipe dia = D = 15.0 in ' Invert elev. = 4908.50 ft (inv. "D" on outlet structure) Eo = 4911.24 ft (downstream HGL for peak 100 yr flow - from FlowMaster) h = 4913.00 ft - 100 yr WSEL ' Co = 0.65 solve for effective area of orifice using the orifice equation ' A. = 0.824 ft` 118.6 in` orifice dia. = d = 12.29 in Check orifice discharge coefficient using Figure 5-21 (Hydraulic Engineering) d/ D = 0.82 kinematic viscosity, v = 1.22E-05 ft2/s Reynolds no. = Red = 40/(7rdv) = 5.81 E+05 Co = (K in figure) = 0.65 check Use d = 12.25 in Ao= 0.818 n`= Qmax = 5.66 cfs 117.86 in` 131 orifice - 100yr, 4-10-18 orifice.xls /.1wiiD►113We I EXCERPTS FROM REFERENCE REPORTS E City of Ft. Collins phi ed Plans Approved By Date FINAL DRAINAGE REPORT Harmony Commons Subdivision Prepared for: Brinkman Partners 3528 Precision Drive, Suite 100 Fort Collins, CO 80528 (970) 667-0954 Prepared by: Interwest Consulting Group 1218 West Ash, Suite A Windsor, Colorado 80550 (970)674-3300 March 11, 2016 Job Number 1254-045-M SNOWWODANOWHVH ............................. .. . ....... --------------------------------- ................... (L 0 .. ... ....... . < < MICROCOSMS! 111111:011:11:1111: 3111101111:211111; BRIMMINSMISM ZME113111311111 aiiiiiiiiiiiiiiiiii 11111:01:111131111 IVIk�bL-- I Pao Ost WB¢ 0n PROVIDED R'GFTI REOWROD 41L'-ATI WBFL ('n WocV PafD •100 MTENTKN Pap 1 49(ti L 1279 I Mn 1 4904.70 1 3.59 DRA69r BDOItl® '1NAD 11e0 fAlIC t00 R16E1 2T0' •' d 10� 12.0' ♦0' 120' *SWALE A -A GROSS SECTION --yroe AT• a-• 2O .•Hm..a......w... mra I•ose+ 6A6BIe IIFMMRN NaAA•mR cV4Iw aR I a bl 1 I ay to Br Na L t to am ON •]I a a an on OM •m N N ON Om ON 2N I a am ta, on am 1 T am Om 02, ON a a it" ON ,40 SON a I 2T6 ON 21l, ,2A1 M N 2" ON 271 1220 at at Noo DNAINAGE BASIN BOUNDARY LINE _ PROPOSED DRAINAGE BASIN ID ACRESIt'VALVE 4 7 erua 1'•,N a tar 200' 1) POD l00 (COMBINED SW M PONDS 101, al awl) HAS BEEN SIZED TO PROVIDE WATER DUALITY AND OE1tENT1ON FOR a6. w ACRES, INCLUDING THE 21 Be ACRES (BABY/S 12)FOR ONSTE MOOFFSITE &-.SINS SNOAN IN THE HTP ROADWAY AND UTILITY INFRASTRUCTURE PROJECT, AS WELL AS THE REMNNING, EXISTING BASIN MEM CONTAINED WITHIN SWAY BASINS 401. W AND SOOT OF THE HIP WAS TERPLM REPORT. AND THE REMUNING EASTERN HALF -WIDTH OF OF TECHNOLOGY PARKWAY (TOTAL OF a60 ACRES) THEREFORE, POND 100 VALL REPLACE AND PROV DE DETENTION AND LATER OUALITY FOR WHAT WAS PREVIOUSLY SHOWN AS PONDS 101. SW, AND 301 OF THE HTP MASTERPLAN SWMM MODEL. TO ALLOW FOR FUTURE DEVELOPMEM OF THE REMAINING PARCEL AREAS, AT A LATER DATE. 2) FUTURE DEVELOPMENT &ORG 111E EAST WE OF TROHMMOGY PARKWAY SOUTH OF nMBERWOOO DRIVE) SHALL CONVEY RUNOFF FROM THE EASTERN HALF-WDTH OF TI CMIOLOGY PARKWAY EAST AND W TO POND M 0) TWO OUTFALL STRUCTURES ME PROPOSED FOR POND 100 THE EASTERN WATER QUALITY/ DETENTION POND OUTLET STRUCTURE NULL PROVIDE FOR A CONTROLLED RELEASE RATE OF 12 CFS (PER HTP MASTERPIAR SWIN MODEL FOR MEVIO IS POND 1111) THE W:STETRN OUTLET STRUCTURE W LL PROVIDE FOR A CONTROLLED RELEASE RATE OF S CFS (PER HTP MASTER" SWUM MODEL FOR PREVIOUS POND I01) THE DRAINAGE BASINS SHOWN ON THIS EXHNT ACCOUNT FOR 21 OS ACRES OF TOTAL ONNSTIE AND OFFSITE BASIN AREAS ATTRIBUTABLE TO THE HTP SIXTH FANG THESE BASIN AREAS. ALONG WITH RATIONAL C' VALUES SHOWN BELOW AND IN THE NATIONAL CALCULATIONS HAVE BEEN UnL12FD TO SIZE THE STORM SEWER INFNASTRUCTURE SHOWN W THESE PLANS AND THE HTP INFRASTRUCTURE IMPROVEMENTS PROJECT, AS WELL AS TO SI2F SW LEA FOR TtIM PROECT. FUTURE DEVELOPMENT OF BASINS 1 AND I SHALL MEET THE 00N IMPERVIOUS RATIO FOR THE SAID BASMS(C VALUES FOR FUTURE DEVELOPMENT SHALL ADHERE TO CORRESPONDING IMPERVIOUS RATIO OF wK IMPERVIOUSNESS. NOT CVALUE OF 0.SO) SHOULD THE DEVELOPED CONDITION OF BASINS 1 AND 6 EXCEED AN 60%, IMPERVIOUSNESS NATIO. ADDITIONAL WATER QALIT AND DETENTION WILL BE REQUIRED. BEYOND THAT SHI IN THE HTP SW MM MODEL. a) W THE INTERN CONDITION. BASINS 1 AND 6 WILL RFM< W THEIR HISTORIC CONDITION. WHICH IS EXISTING. PLARTEDAGRICFORTHEEN11RS FUTURE DEVELOPMENT SHALL CONVEYED E FDR THE PROPOSED YY OF BASINS 1 MD B FIFI CONVEYED TOTHE PROPOSEDSTORM DRAINAGE WFRASTUCTUREHISPLAN SHOWN! (EACH PLAN MOBILE IN AND HD CORRESPONDING EACHATTRIBUTABLEBASIN AND THE CIXRRESPDIpNG DESIGN PONT FOR EACH BASIN, 6) THE INTERIM COBBLE PITSAJISCHARGE POINTS (LOCATED SOUTH OF TIMBERWOOD DRIVE) ME PROWOED FOR THE BfTFAW CONDITION ONLY. LID AND BMP MEASURES FOR BASINS I THROUGH 10 SHALL BE PROW DD BY OTHERS WITH FUTURE DEVELOPMENT. 6) SEE MTKJNAL METHOD CALCUUI%1RS FOR COMBINED, ATTENUATED FLOW FROM COMBINED BASINS FOR STORM SEWER STALE SIZING 7)17 OF COOT CLASS'A' BEDDING MATERIAL STALL BE PLACED UNDER ALL RIPRM SHOWN. ALL RIPRM SHALL BE COVERED WIN V OF TOPSOIL. 6) SEE SHEET ASP2 FOR MASTER LEGEND 2) FUTURE DEVELOPMENT EAST/ SOUTHEAST OF THE REGIONAL DETENTION POND SHALL BE DESIGNED TO ENSURE A POSHIVE OVERFLOW PATH TO THE EAST AND INTO LADY MOON DRIVE. City of Fort Collins, Colorado UTILITY PLAN APPROVAL APPROVED: City Engineer Dote - CHECKED BY: Rater h Wosteaalm Utility Dote CHECKED BY: Slam•der DUST, Date CHECKED BY;—_ Parks t Reueatim Date QPROPOSED DRAINAGE DESIGN FONT CHECKED RY: Tmffc EngiI,em Doe —� PROPOSED DRAINAGE FLOW PATH CHECKED — 105 — PROPOSED INDEX CONTOUR - 6 FT INTERVAL EnvOonmenid Pbnror DOM — 106 — PROPOSED INTERMEDIATE CONTOUR-1 FT INTERVAL THESE PINS HAVE BEEN REVIEWED BY THE LO!L — 4910 — OUSONG INDEX CONTOUR-6 FT INTERVAL ENT" FOR CONCEPT ONLY. THE REVIEW DOES NOT IMPLY RESPONSIBILITY BY THE RENEWNG — — 4911 — — EXISTING INTERMEDIATE CONTOUR-1 FT NTERVAI DEPARTMENT THE LOCAL ENTITY ENC►EER. OR THE LOCAL EARN FOR ACCURACY AND CORRECTNESS OF THE CALCULATIONS. FLURTHEROM, THE REVIEW DOES CALL UTILITY NOTIFICATION NOT IMPLY THAT WAHDIES OF ITEMS ON THE %.INS CENTEROFCCLORADO ARE THE FINAL QUANTITIES RFEW OURED. THE REVI 1-800-922-1987 � NOT BE DDNS,NED IN ANY SON A5 rWLR w.wMUala NAovArce ACCEPTANCE OF FROMM RESPON OKM BY THE M Myotmna M "D VAM LOCAL ENITIY FOR ADDITIONAL DIA ITIES OF ME w111E1�°'MN1pI OWM p SHOWN THAT MAY BE REOtOW DURM THE CONSTRUCTION PRISE. E i CHECKED BY. J� DE6K23DBY &M DRAWN BY &W� D RE Q L�` NNWMXCTWX 1000111 "To Tnoilo SHEET NO: ASPS s Or 9 ���- --- :r -3 L_ lit- INTEL ,I R \ -------- (14 PON tt `u i i - HP KARMONY ROAD' �:1Nf1I■1■ ' i'..r _----_� - - - I !----�PROPOSA,, 00 J h 101 .lo =sas PROPOSED STORM OUTLET SL \ ° PRopOBED,S SI 205 QT=10cfs f s I { \ O -HARMONY TECHNOLOGY PMK, ��� ■� / \ I 6 � I \ \ ( / I \� I P z- \ I 1 01 l\ / - 501 PROPOSED 1W STORM OUTLET / STORM STORM / i / ; - - - ----1 - -- - -�-- E)OSTING 30• STORM STORM OUTLET �{905 RG M' STORM ABANDONED LEGEND —(wu)— RmTs■smirunloult-sns,1■NK ---- (w1b)---- E1�IN9 NR■1mlAT6 COlIIOIR • t f'T NIERVK 100 SWot/fAs►1 ao DETEwnoN °oto 0 IIODE stesAsa COMC'OON sm ROUTO G MEMEM - — sAss.slsraseT ■i.: F.LS S'� `.A�!1fi:'!I}Y� t�bY���!![?.ice E[^.-� iF6� ■ } �i1(t .lA .fit RLG�lA:.�l:Ildt•�j'�j'�•' ■ lY �i■t v.�t� {R\f![.\1•tR'•t•�a('!�(:>•S1�j'F1' ■- '. ■r;■■t 1C r'.1•fi w;.t•lcs�tliR�1_iR��t•T.)♦ ■i: .. [� �■f=: }: o:�iltt�ihr ffiA ;.l•t••A:.f�llf.i�E[j'iDi�� PROPOSED STORM OUTLET 41 TOEWBTING ABANDONED � � � To BE AeA„DosED I I I '�-EGBTMS 3W SPDRM OPOSED 4S• STORM EmTMG 3a• STORM TO BE ASMIDOIED EXISTING 36• STORM EXISTING 53• X sr ELUPTICAL STORM r a rL �W � a m � s Pmdsd EMBIT ROTFM COVIBTRUCrQH E..I.A - 1 ti IIw° t■YJC..�.m-�hol u ,v Rs aua ft*Q a SWMM RBW$b SIRR loll EXISTING t+ 4 INLET AND 15" •r ��— HP STORM PIPE too, 20 -HARMONY ROAD ===ram — EXISTjNG ROADWAY II EX5 1 ^ rj f I I I \ EXISTING I GATION I DRAINAGE DITCH / asuc IIII f� PLAPY IPE & DIT l \ I III Mato 113Le,r 1 C4 � I l 1 I ^ r l !I! awft I / ,e� / i • �— q EXISTING DETENTION r ! , 1 l I / 1 EXISTING 24" STORM i 1 r I � / Y A/ 1 /r I 21" OVERFLOW ST,0K�M PIPE mr/ ♦ i mupowALSTING/15RIVATE 0 000,I DITCH ^� I MAC �V I � / \ e RMONY TECHNOLOGY PARK _ S-1woopwoo \ 40 \ I \ / / AASTOL / I 1 n / \ h / EXISTING 24"4910) y a EXISTING 24" STORM EXISTING 15" STORM — EXISTING DETENTION EXISTING 30" STORM EXISTING 36" STORM - EXISTING 36" STORM EXISTING 30" STORM EXISTING 53" X 83" � \III ELLIPTICAL STORM EXISTING 36" STORM