6 STOREY CONDOMINIUM 7480 DERRY ROAD WEST, MILTON

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1 6 STOREY CONDOMINIUM 7480 DERRY ROAD WEST, MILTON STORM WATER MANAGEMENT DESIGN BRIEF NEW DEVELOPMENT DRAINAGE SYSTEM REV 0 August 29, 2017 PREPARED BY: HALLEX PROJECT # HALLEX NIAGARA HALLEX HAMILTON 4999 VICTORIA AVENUE 745 SOUTH SERVICE ROAD, UNIT 205 NIAGARA FALLS, ON L2E 4C9 STONEY CREEK, ON L8E 5Z2

2 6 Storey Condominium Hallex Project # Derry Road West, Milton Issued for Site Plan Approval TABLE OF CONTENTS Page 1. PRE-DEVELOPMENT CONDITIONS LOCATION DRAINAGE PATTERN PROPOSED WORK GRADING DRAINAGE DESIGN CONSIDERATIONS SITE DRAINAGE Pre-development... 1 A. Peak Runoff... 1 B. Quantity... 2 C. Quality Post Development... 2 A. Peak Runoff... 2 B. Quantity... 3 C. Quality... 3 D. Maintenance Recommendations... 3 PRE-DEVELOPMENT CATCHMENT AREA PLAN POST-DEVELOPMENT CATCHMENT AREA PLAN EXHIBITS Storm Water Management Design APPENDIX A Stormceptor STC-750 Sizing Calculations & Schematic HALLEX ENGINEERING LTD.

3 6 Storey Condominium Hallex Project # Derry Road West, Milton Issued for Site Plan Approval 1. PRE-DEVELOPMENT CONDITIONS 1.1 LOCATION The proposed 6 storey condominium is located at 7480 Derry Road West, being between Farmstead Drive and Santa Maria Boulevard on the southerly side of Derry Road, in Milton, ON. 1.2 DRAINAGE PATTERN The current drainage path for the site consists primarily of overland sheet flow to the existing DICB located at the south east corner of the site and some areas draining to the adjacent street. The existing sewer at the south east corner of the site has been designed according to the 100 year storm event. 2. PROPOSED WORK 2.1 GRADING The objective of the design is to utilize the existing natural slope and achieve the minimum and maximum slopes in the grading of the asphalt surface. This will ensure the asphalt surface not only drains as per the design, but is not too steep. The grading of the site also ensures that the storm water flow will mostly drain through the onsite storm sewer system for storm water quality control. 2.2 DRAINAGE The proposed design requires metres of solid main storm sewer, 3 parking structure roof drains, a trench drain complete with sump pump chamber, four precast catchbasin manholes, metres of perforated HDPE sub-drain, 6 turf drains and a Stormceptor STC-750 oil/grit separator. 3. DESIGN CONSIDERATIONS 3.1 SITE DRAINAGE Pre-development A. Peak Runoff The total drainage area for the subject site is hectares with an existing runoff coefficient of 0.64 based on existing roof, paved, gravel and grass surface areas. The time of concentration is determined to be 10 minutes to the start of the sewer as required by the Town of Milton Municipal Standards. Using the Rational Method, the peak flow rates are Q = CiA 360 HALLEX ENGINEERING LTD. Page 1 of 4

4 6 Storey Condominium Hallex Project # Derry Road West, Milton Issued for Site Plan Approval Subcatchment Description Draining to Area, ha Tc, min Area.1 Sheet flow XDICB For 5-year Storm A,ha C i,mm/h Q, L/s Area For 100-year Storm A,ha C i,mm/h Q, L/s Area B. Quantity There is no known storm quantity control measure in place for the pre-development condition. C. Quality There is no known storm quality control measure in place for the pre-development condition Post Development A. Peak Runoff The proposed 6 storey residential development consists of the construction of a new building and parking structure. The resulting runoff coefficient is The post development site will drain via new storm sewers to the existing double inlet catchbasin at located at the south east corner of the site. The site s storm sewer pipes are designed according to the 5 year minor storm. The grassed boulevard fronting the proposed building will continue to drain to the adjacent street via sheet flow. Utilizing the minimum recommended time of concentration of 10 minutes, the time for storm water to flow from the farthest pipe to the existing municipal sewer, as outlined in Exhibit #1, is calculated to be minutes. Using the Rational Method, the peak flow rates are as follows: HALLEX ENGINEERING LTD. Page 2 of 4

5 6 Storey Condominium Hallex Project # Derry Road West, Milton Issued for Site Plan Approval Subcatchment Description Draining to Area, ha Tc, min Area.1 Sheet flow Street Sewer Sewer flow Street For 5-year Storm A,ha C i,mm/h Q, L/s Area Sewer TOTAL For 100-year Storm A,ha C i,mm/h Q, L/s Area Sewer TOTAL The flows and other design information are contained in Exhibit #1 for the 5 year storm and Exhibit #2 for the 100 year storm at the end of the design brief. B. Quantity The post-development storm water runoff for the subject site has increased by only 14.0L/s for the five year storm and 23.1L/s for the one hundred year storm. As such, no further the storm water quantity controls are proposed for the site. In the 100 year storm event, some of the proposed pipes will surcharge during the peak flow. The required head heights for the surcharged pipes to meet these peak flows are calculated to ensure the storm water will be fully contained within the storm sewer system. The flows, head heights and other design information are contained in Exhibit #3-9 for the surcharged pipes at Drain.2, RWL, CBMH.1, CBMH.2, CBMH.3, CBMH.4 and OGS respectively. C. Quality The storm water collected in the proposed development passes through a Stormceptor STC-750, which achieves a total suspended solids removal of at least 77%. This value equal to the required Normal treatment of 70% as indicated in the MOE Stormwater Management Planning and Design Manual, dated March 2003 (refer to Chapter 3: Environmental Design Criteria, Section Level of Protection). The design calculations from the manufacturer as well as the drawings for the unit are included in Appendix A of this report. D. Maintenance Recommendations The storm sewer system includes pipes, parking structure roof drains, a trench drain complete with sump pump chamber, precast catchbasin manholes, turf drains and an oil/grit separator. It is important to regularly inspect the elements to ensure that storm water is flowing as originally designed. Debris and sediment commonly clog the system and reduce the overall effectiveness. HALLEX ENGINEERING LTD. Page 3 of 4

6 6 Storey Condominium Hallex Project # Derry Road West, Milton Issued for Site Plan Approval The following maintenance and inspection tasks should be done: 1. Inspect the inlet pipes and outlet pipes for structural integrity. (Annually) Check inlet/ outlet pipes for structural integrity to ensure they aren t crumbling or broken. 2. Conduct routine inspections for trash or other debris that may be blocking the inlet and outlet pipes. (Monthly and after rain events) Remove all trash and debris. 3. Inspect and clean the storm sewer system (Every 5 years or as needed). Catchbasins to be inspected annually and debris removed when the debris reaches a depth of ½ from the bottom of the sump to the bottom of the pipe. 4. Inspect for sediment accumulation at pipes (Semi-annually and after rain events). It is important to clean out sediment that might be restricting water flow. 5. Do not dump any materials in the storm sewer system. 6. Inspect the Stormceptor Oil/Grit Separator (Annually). Procedures for inspection are provided in the Stormceptor Owner s Manual. A vacuum truck is to be used for maintenance of the Stormceptor. Yours truly, HALLEX ENGINEERING LTD Jim Halucha P.Eng Civil/Structural Engineer Jonathan Skinner, C.E.T., B.Tech Civil Technologist HALLEX ENGINEERING LTD. Page 4 of 4

7 AREA LEGEND CATCHMENT AREA AREA (HECTARES) AVERAGE RUNOFF COEFFICIENT PROJECT: 6 STOREY CONDOMINIUM 7480 DERRY ROAD WEST, MILTON, ON. SHEET TITLE: PRE-DEVELOPMENT CATCHMENT AREA PLAN DATE: 08/29/2017 JOB No.: SCALE: 1:600 DWG. REV. DR. BY: JS CH. BY: JH

8 AREA TD.4 DRAIN TD.3 DRAIN.2 RWL TD TD DRAIN.3 TD.5 TD.6 TRENCH DRAIN.3 CBMH.4 TD.2 DRAIN.1 DRAIN TD CBMH TRENCH CBMH.1 TD.1 CBMH CBMH.2 TD.2 CBMH CBMH.3 TD.3 TD.6 XDICB.1 OGS CBMH.4 LEGEND CATCHMENT AREA AREA (HECTARES) AVERAGE RUNOFF COEFFICIENT PROJECT: 6 STOREY CONDOMINIUM 7480 DERRY ROAD WEST, MILTON, ON. SHEET TITLE: POST-DEVELOPMENT CATCHMENT AREA PLAN DATE: 07/20/2017 JOB No.: SCALE: 1:600 DWG. REV. DR. BY: JS CH. BY: JH 08/29/2017 0

9 7480 Derry Road West, Milton Exhibit #1-5 Year Post - Development Calculations 8/29/2017 Job: Rainfall Intensity Values = A= manning's n = PVC Pipe ref# 37 B= Conc Pipe C= Corr. Stl Pipe Grass Swale Location Area Flow Time Design Flows Sewer Design Invert Elevations Length Rainfall Unit rate Increment Total Upper Section Flow Full Full meter stream stream Cum To In Cum of Pipe Intensity of Runoff Cum Flow Slope Capacity Velocity Dia- Up- Down- Pipe From Node To Node (m) (ha) (ha) (min) (min) mm/hr m 3 /ha*day (m 3 /d) (m 3 /s) (m/m) (m 3 /s) (m/s) (m) (m) (m) 1 Area 1 Street N/A N/A N/A N/A N/A N/A N/A N/A Paved Grass Drain. 1 Drain Paved Grass Trench Sump Paved Sump Drain. 2 N/A N/A N/A N/A N/A N/A 5 Drain. 2 CBMH Paved Grass CBMH. 1 CBMH Paved Grass RWL CBMH Roof Drain. 3 CBMH Paved Grass CBMH. 2 CBMH Paved Grass CBMH. 3 CBMH Paved Grass TD. 1 TD Grass TD. 2 TD Grass TD. 3 CBMH Grass Victoria Avenue Niagara Falls, ON L2E 4C9 1 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

10 7480 Derry Road West, Milton Exhibit #1-5 Year Post - Development Calculations 8/29/2017 Job: Location Area Flow Time Design Flows Sewer Design Invert Elevations Length Rainfall Unit rate Increment Total Upper Section Flow Full Full meter stream stream Cum To In Cum of Pipe Intensity of Runoff Slope Capacity Velocity Dia- Up- Down- Cum Flow Pipe From Node To Node (m) (ha) (ha) (min) (min) mm/hr m 3 /ha*day (m 3 /d) (m 3 /s) (m/m) (m 3 /s) (m/s) (m) (m) (m) 14 TD. 4 TD Paved Grass TD. 5 TD Grass TD. 6 CBMH Paved Grass CBMH. 4 OGS Grass OGS XDICB Run-off Coefficients Used: Velocity Range: Time of Concentration: Roof Structure C = 0.95 Minimum Velocity = 0.75 m/s Time of Concentration = 10 min Paved Surface C = 0.90 Maximum Velocity = 6.00 m/s Grass Surface C = Victoria Avenue Niagara Falls, ON L2E 4C9 2 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

11 7480 Derry Road West, Milton Exhibit #2-100 Year Post - Development Calculations 8/29/2017 Job: Rainfall Intensity Values = A= manning's n = PVC Pipe ref# 41 B= Conc Pipe C= Corr. Stl Pipe Grass Swale Location Area Flow Time Design Flows Sewer Design Invert Elevations Length Rainfall Unit rate Increment Total Upper Section Flow Full Full meter stream stream Cum To In Cum of Pipe Intensity of Runoff Cum Flow Slope Capacity Velocity Dia- Up- Down- Pipe From Node To Node (m) (ha) (ha) (min) (min) mm/hr m 3 /ha*day (m 3 /d) (m 3 /s) (m/m) (m 3 /s) (m/s) (m) (m) (m) 1 Area 1 Street N/A N/A N/A N/A N/A N/A N/A N/A Grass Drain. 1 Drain Paved Grass Trench Sump Paved Sump Drain. 2 N/A N/A N/A N/A N/A N/A 5 Drain. 2 CBMH Paved Grass CBMH. 1 CBMH Paved Grass RWL CBMH Roof Drain. 3 CBMH Paved Grass CBMH. 2 CBMH Paved Grass CBMH. 3 CBMH Paved Grass TD. 1 TD Grass TD. 2 TD Grass TD. 3 CBMH Grass Victoria Avenue Niagara Falls, ON L2E 4C9 3 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

12 7480 Derry Road West, Milton Exhibit #2-100 Year Post - Development Calculations 8/29/2017 Job: Location Area Flow Time Design Flows Sewer Design Invert Elevations Length Rainfall Unit rate Increment Total Upper Section Flow Full Full meter stream stream Cum To In Cum of Pipe Intensity of Runoff Slope Capacity Velocity Dia- Up- Down- Cum Flow Pipe From Node To Node (m) (ha) (ha) (min) (min) mm/hr m 3 /ha*day (m 3 /d) (m 3 /s) (m/m) (m 3 /s) (m/s) (m) (m) (m) 14 TD. 4 TD Paved Grass TD. 5 TD Grass TD. 6 CBMH Paved Grass CBMH. 4 OGS Grass OGS XDICB Run-off Coefficients Used: Velocity Range: Time of Concentration: Roof Structure C = 0.95 Minimum Velocity = 0.75 m/s Time of Concentration = 10 min Paved Surface C = 0.90 Maximum Velocity = 6.00 m/s Grass Surface C = Victoria Avenue Niagara Falls, ON L2E 4C9 4 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

13 7480 Derry Road West, Milton Exhibit #3 - RWL 100 Year Head Height Calcs 8/29/2017 Job: Site Data Flow Site Discharge (m 3 /s) Pipe Capacity Year Flow Control Node Data Pipe Storm Control Node Pipe Size Invert Elev. Orifice (m) (m) (m) 5 Drain Head Height 0.26 m Storm Retention Elev. Check m Flow Rate for Pipe (Q=Cd*A*sqrt(2*g*h)) Coefficient of Discharge Cd = 0.8 (tube) 0.62 Sharp Orifice coefficient of discharge Dia of Pipe dia = 200 mm 0.80 Tube coefficient of discharge Area of Pipe A = 0.03 m 2 Force of Gravity g = 9.81 m/s/s Head Height h = 0.26 m Flow Rate through Pip Q = m 3 /s 4999 Victoria Avenue Niagara Falls, ON L2E 4C9 5 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

14 7480 Derry Road West, Milton Exhibit #4 - Drain Year Head Height Calcs 8/29/2017 Job: Site Data Flow Site Discharge (m 3 /s) Pipe Capacity Year Flow Control Node Data Pipe Storm Control Node Pipe Size Invert Elev. Orifice (m) (m) (m) 7 RWL Head Height 0.28 m Storm Retention Elev. Check m Flow Rate for Pipe (Q=Cd*A*sqrt(2*g*h)) Coefficient of Discharge Cd = 0.8 (tube) 0.62 Sharp Orifice coefficient of discharge Dia of Pipe dia = 300 mm 0.80 Tube coefficient of discharge Area of Pipe A = 0.07 m 2 Force of Gravity g = 9.81 m/s/s Head Height h = 0.28 m Flow Rate through Pip Q = m 3 /s 4999 Victoria Avenue Niagara Falls, ON L2E 4C9 6 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

15 7480 Derry Road West, Milton Exhibit #5 - CBMH Year Head Height Calcs 8/29/2017 Job: Site Data Flow Site Discharge (m 3 /s) Pipe Capacity Year Flow Control Node Data Pipe Storm Control Node Pipe Size Invert Elev. Orifice (m) (m) (m) 6 CBMH Head Height 0.19 m Storm Retention Elev. Check m Flow Rate for Pipe (Q=Cd*A*sqrt(2*g*h)) Coefficient of Discharge Cd = 0.8 (tube) 0.62 Sharp Orifice coefficient of discharge Dia of Pipe dia = 250 mm 0.80 Tube coefficient of discharge Area of Pipe A = 0.05 m 2 Force of Gravity g = 9.81 m/s/s Head Height h = 0.19 m Flow Rate through Pip Q = m 3 /s 4999 Victoria Avenue Niagara Falls, ON L2E 4C9 7 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

16 7480 Derry Road West, Milton Exhibit #6 - CBMH Year Head Height Calcs 8/29/2017 Job: Site Data Flow Site Discharge (m 3 /s) Pipe Capacity Year Flow Control Node Data Pipe Storm Control Node Pipe Size Invert Elev. Orifice (m) (m) (m) 9 CBMH Head Height 0.41 m Storm Retention Elev. Check m Flow Rate for Pipe (Q=Cd*A*sqrt(2*g*h)) Coefficient of Discharge Cd = 0.8 (tube) 0.62 Sharp Orifice coefficient of discharge Dia of Pipe dia = 375 mm 0.80 Tube coefficient of discharge Area of Pipe A = 0.11 m 2 Force of Gravity g = 9.81 m/s/s Head Height h = 0.41 m Flow Rate through Pip Q = m 3 /s 4999 Victoria Avenue Niagara Falls, ON L2E 4C9 8 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

17 7480 Derry Road West, Milton Exhibit #7 - CBMH Year Head Height Calcs 8/29/2017 Job: Site Data Flow Site Discharge (m 3 /s) Pipe Capacity Year Flow Control Node Data Pipe Storm Control Node Pipe Size Invert Elev. Orifice (m) (m) (m) 10 CBMH Head Height 0.50 m Storm Retention Elev. Check m Flow Rate for Pipe (Q=Cd*A*sqrt(2*g*h)) Coefficient of Discharge Cd = 0.8 (tube) 0.62 Sharp Orifice coefficient of discharge Dia of Pipe dia = 375 mm 0.80 Tube coefficient of discharge Area of Pipe A = 0.11 m 2 Force of Gravity g = 9.81 m/s/s Head Height h = 0.50 m Flow Rate through Pip Q = m 3 /s 4999 Victoria Avenue Niagara Falls, ON L2E 4C9 9 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

18 7480 Derry Road West, Milton Exhibit #8 - CBMH Year Head Height Calcs 8/29/2017 Job: Site Data Flow Site Discharge (m 3 /s) Pipe Capacity Year Flow Control Node Data Pipe Storm Control Node Pipe Size Invert Elev. Orifice (m) (m) (m) 17 CBMH Head Height 0.54 m Storm Retention Elev. Check m Flow Rate for Pipe (Q=Cd*A*sqrt(2*g*h)) Coefficient of Discharge Cd = 0.8 (tube) 0.62 Sharp Orifice coefficient of discharge Dia of Pipe dia = 375 mm 0.80 Tube coefficient of discharge Area of Pipe A = 0.11 m 2 Force of Gravity g = 9.81 m/s/s Head Height h = 0.54 m Flow Rate through Pip Q = m 3 /s 4999 Victoria Avenue Niagara Falls, ON L2E 4C9 10 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

19 7480 Derry Road West, Milton Exhibit #9 - OGS 100 Year Head Height Calcs 8/29/2017 Job: Site Data Flow Site Discharge (m 3 /s) Pipe Capacity Year Flow Control Node Data Pipe Storm Control Node Pipe Size Invert Elev. Orifice (m) (m) (m) 18 OGS Head Height 0.54 m Storm Retention Elev. Check m Flow Rate for Pipe (Q=Cd*A*sqrt(2*g*h)) Coefficient of Discharge Cd = 0.8 (tube) 0.62 Sharp Orifice coefficient of discharge Dia of Pipe dia = 375 mm 0.80 Tube coefficient of discharge Area of Pipe A = 0.11 m 2 Force of Gravity g = 9.81 m/s/s Head Height h = 0.54 m Flow Rate through Pip Q = m 3 /s 4999 Victoria Avenue Niagara Falls, ON L2E 4C9 11 of South Service Road, Unit 205 Stoney Creek, ON L8E 5Z2

20 APPENDIX A Stormceptor STC-750 Sizing Calculations and Schematic HALLEX ENGINEERING LTD.

21 Detailed Stormceptor Sizing Report 7480 Derry Road West, Milton Project Information & Location Project Name 7480 Derry Road West, Milton Project Number City Milton State/ Province Ontario Country Canada Date 8/28/2017 Designer Information EOR Information (optional) Name Jon Skinner Name Company Hallex Engineering Ltd Company Phone # Phone # jskinner@hallex.ca Stormwater Treatment Recommendation The recommended Stormceptor Model(s) which achieve or exceed the user defined water quality objective for each site within the project are listed in the below Sizing Summary table. Site Name Recommended Stormceptor Model STC 750 Target TSS Removal (%) 70.0 TSS Removal (%) Provided 77 PSD Rainfall Station Fine Distribution TORONTO CENTRAL The recommended Stormceptor model achieves the water quality objectives based on the selected inputs, historical rainfall records and selected particle size distribution. Stormceptor Sizing Summary Stormceptor Model % TSS Removal Provided STC STC STC STC STC STC STC STC STC STC STC STC StormceptorMAX Custom Stormceptor Detailed Sizing Report Page 1 of 8

22 Stormceptor The Stormceptor oil and sediment separator is sized to treat stormwater runoff by removing pollutants through gravity separation and flotation. Stormceptor s patented design generates positive TSS removal for each rainfall event, including large storms. Significant levels of pollutants such as heavy metals, free oils and nutrients are prevented from entering natural water resources and the re-suspension of previously captured sediment (scour) does not occur. Stormceptor provides a high level of TSS removal for small frequent storm events that represent the majority of annual rainfall volume and pollutant load. Positive treatment continues for large infrequent events, however, such events have little impact on the average annual TSS removal as they represent a small percentage of the total runoff volume and pollutant load. Design Methodology Stormceptor is sized using PCSWMM for Stormceptor, a continuous simulation model based on US EPA SWMM. The program calculates hydrology using local historical rainfall data and specified site parameters. With US EPA SWMM s precision, every Stormceptor unit is designed to achieve a defined water quality objective. The TSS removal data presented follows US EPA guidelines to reduce the average annual TSS load. The Stormceptor s unit process for TSS removal is settling. The settling model calculates TSS removal by analyzing: Site parameters Continuous historical rainfall data, including duration, distribution, peaks & inter-event dry periods Particle size distribution, and associated settling velocities (Stokes Law, corrected for drag) TSS load Detention time of the system Hydrology Analysis PCSWMM for Stormceptor calculates annual hydrology with the US EPA SWMM and local continuous historical rainfall data. Performance calculations of Stormceptor are based on the average annual removal of TSS for the selected site parameters. The Stormceptor is engineered to capture sediment particles by treating the required average annual runoff volume, ensuring positive removal efficiency is maintained during each rainfall event, and preventing negative removal efficiency (scour). Smaller recurring storms account for the majority of rainfall events and average annual runoff volume, as observed in the historical rainfall data analyses presented in this section. Rainfall Station State/Province Ontario Total Number of Rainfall Events 3329 Rainfall Station Name TORONTO CENTRAL Total Rainfall (mm) Station ID # 0100 Average Annual Rainfall (mm) Coordinates 45 30'N, 90 30'W Total Evaporation (mm) Elevation (ft) 328 Total Infiltration (mm) Years of Rainfall Data 18 Total Rainfall that is Runoff (mm) Notes Stormceptor performance estimates are based on simulations using PCSWMM for Stormceptor, which uses the EPA Rainfall and Runoff modules. Design estimates listed are only representative of specific project requirements based on total suspended solids (TSS) removal defined by the selected PSD, and based on stable site conditions only, after construction is completed. For submerged applications or sites specific to spill control, please contact your local Stormceptor representative for further design assistance. Stormceptor Detailed Sizing Report Page 2 of 8

23 Drainage Area Total Area (ha) Imperviousness % 73.5 Water Quality Objective TSS Removal (%) 70.0 Runoff Volume Capture (%) Oil Spill Capture Volume (L) Peak Conveyed Flow Rate (L/s) Water Quality Flow Rate (L/s) Up Stream Storage Storage (ha-m) Discharge (cms) Up Stream Flow Diversion Max. Flow to Stormceptor (cms) Design Details Stormceptor Inlet Invert Elev (m) Stormceptor Invert Elev (m) Stormceptor Rim Elev (m) Normal Water Level Elevation (m) Pipe Diameter (mm) Pipe Material Multiple Inlets (Y/N) No Grate Inlet (Y/N) No Particle Size Distribution (PSD) Removing the smallest fraction of particulates from runoff ensures the majority of pollutants, such as metals, hydrocarbons and nutrients are captured. The table below identifies the Particle Size Distribution (PSD) that was selected to define TSS removal for the Stormceptor design. Particle Diameter (microns) Fine Distribution Distribution % Specific Gravity Stormceptor Detailed Sizing Report Page 3 of 8

24 Site Name Site Details Drainage Area Total Area (ha) Imperviousness % 73.5 Surface Characteristics Width (m) Slope % 2 Impervious Depression Storage (mm) Pervious Depression Storage (mm) 5.08 Impervious Manning s n Pervious Manning s n 0.25 Maintenance Frequency Maintenance Frequency (months) > 12 Infiltration Parameters Horton s equation is used to estimate infiltration Max. Infiltration Rate (mm/hr) Min. Infiltration Rate (mm/hr) Decay Rate (1/sec) Regeneration Rate (1/sec) 0.01 Evaporation Daily Evaporation Rate (mm/day) 2.54 Dry Weather Flow Dry Weather Flow (lps) 0 Winter Months Winter Infiltration 0 TSS Loading Function TSS Loading Parameters Buildup/Wash-off Parameters Target Event Mean Conc. (EMC) mg/l Exponential Buildup Power Exponential Washoff Exponent TSS Availability Parameters Availability Constant A Availability Factor B Availability Exponent C Min. Particle Size Affected by Availability (micron) Stormceptor Detailed Sizing Report Page 4 of 8

25 Cumulative Runoff Volume by Runoff Rate Cumulative Runoff Volume Runoff Rate (L/s) Runoff Volume (m³) Volume Over (m³) (%) Stormceptor Detailed Sizing Report Page 5 of 8

26 Stormceptor Detailed Sizing Report Page 6 of 8

27 Rainfall Depth (mm) No. of Events Rainfall Event Analysis Percentage of Total Events (%) Total Volume (mm) Percentage of Annual Volume (%) Stormceptor Detailed Sizing Report Page 7 of 8

28 For Stormceptor Specifications and Drawings Please Visit: Stormceptor Detailed Sizing Report Page 8 of 8

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