Julia Bahen, Urban Strategies Inc.

Transcription

1 THE MUNICIPAL INFRASTRUCTURE GROUP LTD Dufferin Street, Suite 200 Vaughan, Ontario L4K 0C5 T F TECHNICAL MEMORANDUM DATE June 13, 2017 TO CC SUBJECT FROM PROJECT NUMBER Introduction Julia Bahen, Urban Strategies Inc. Bernard KDA Secondary Plan - Preliminary Servicing Analysis Kevin Brown, P.Eng. The Municipal Infrastructure Group Ltd. (TMIG) has been retained by Urban Strategies to conduct a servicing analysis to assess the existing sanitary sewer, storm sewer and watermain systems in the study area and the capacity for the potential redevelopment of the Bernard Key Development Area (KDA). As per the recommended development concept by Urban Strategies Inc., a preliminary servicing analysis was performed for the KDA. Background information for the servicing networks was obtained from the Town of Richmond Hill Urban MESP dated May The MESP InfoSewer models, InfoWater model and Town s design criteria were referenced for the analysis. A preliminary stormwater management analysis was completed to analyze the impact of development within the Bernard KDA as well as to understand the existing condition of the study area. Background information from the Richmond Hill Urban MESP dated May 2014, and governing agency s SWM criteria were referenced for the analysis. 2 Sanitary Collection System 2.1 Previous Richmond Hill Urban MESP Findings The development of the Bernard KDA was previously considered as part of the Richmond Hill Urban MESP (TMIG, 2014). The recommended MESP alternative was that the redevelopment within the area of the Bernard KDA could be serviced with combination of using available capacity in existing local sewers and diverting the excessive flows via new local sewers directly to the Regional trunk. 2.2 Proposed Sanitary Requirements The sanitary servicing requirements for the Bernard KDA have been calculated based on the recommended development densities by Urban Strategies dated May The proposed sanitary flow calculations are shown in Attachment Methodology The InfoSewer hydraulic model provided by the Town has been used to analyze the capacity of the existing sanitary collection system. Per the Town s design criteria, residential flows of 365 Lpcd and employment flows of 90,000 L/ha/day have been considered. Six existing sanitary sewer reaches were identified as having the potential to service the KDA. All of these reaches originate within or immediately adjacent to the Study Area, with only minor external flows from adjacent sanitary sub catchments as the analysis proceeds downstream. Attachment 2 shows the sanitary sewer reaches servicing the KDA lands. Future flows were simulated for Ultimate buildout sanitary design flows and infrastructure based on the Richmond Hill Urban MESP. The Ultimate buildout scenario was established at the time of the MESP, and the sanitary flows for the Bernard KDA were updated based on the recommended development densities (May 2017 concept plan). This method accounts for the future intensification flows from the nearby sub catchments external to the Bernard KDA, based on the projected future population and employment statistics available at the time of Richmond Hill MESP MEMO - Background Servicing Review

2 MEMORANDUM PAGE 2 of 4 JUNE 13, Results The modelling results indicate that there is sufficient existing and future reserve capacity in the current sanitary collection system, to service the North East, North West and SE1, SE2 and SE3 parcels of South East quadrants of the KDA. Sanitary Reach C servicing the South West quadrant of the KDA will surcharge under the full redevelopment of the Bernard KDA, and will need new local sewers connecting to the Regional trunk sewer on Yonge St. These results are consistent with the Richmond Hill MESP findings. The Hydraulic Grade line profile for the sanitary sewer reaches servicing the study area provided in Attachment Recommendations As per the Richmond Hill Urban MESP recommendation, Use the available capacity first, then build local sewers and connect directly to the Regional trunk at three existing manhole locations to collect the flows in excess of the available capacity. This option is particularly attractive because the Regional trunk is located on the east side of Yonge Street.. The Bernard KDA lands are serviceable through a combination of existing sewers east and west of the KDA and through new connections to the Yonge Street Regional Trunk Sewer. The First servicing alternative is to use the existing available capacity for the North East, North West and part of South East quadrants of the KDA. Then build local sewers along the Yonge Street frontage to service SE3 and SE4 and connect to Regional Trunk along Yonge St via existing the existing manhole. To service the South West quadrant, build local sewers along proposed new road, upgrade the existing sewers along the frontage of parcel SW5 and connect to Regional Trunk across Yonge St via the existing manhole. Preliminary sizing for new local sewers along the Yonge Street frontage to service SE3 and SE4 would be 375 mm at 0.5% slope, new local sewers of 250 mm along the proposed new roads at 0.5% slope, and upgrade the existing sewers to 375 mm along the frontage of parcel SW5 at the existing slope. This is a hybrid of recommendations 15-A and 15-B from the MESP, connecting one manhole south of what had been identified in the MESP. An alternate solution to be discussed with the Region is the possibility of installing a new manhole at the intersection of Yonge Street and the new East-West Street. The new local sewer along the proposed road could potentially connect to Regional Trunk along Yonge St via that new Manhole. This alternative would decrease the total length of new sewers required, but installing a new manhole onto the Regional sewer might not be feasible. A detailed review of the underground services at that proposed intersection would also have to be reviewed to determine whether the new sewer could cross Yonge Street. Attachment 4 shows the sanitary servicing alternatives for the KDA lands. 3 Water Analysis 3.1 Previous Richmond Hill Urban MESP Findings The development of Bernard KDA was previously considered as part of the Richmond Hill Urban MESP (TMIG, 2014). The capacity of the existing water distribution system was analyzed using InfoWater. Based on the MESP, the Town s existing water distribution system is generally sufficiently sized to accommodate the potential intensification within the area of the Bernard KDA. 3.2 Proposed Water Requirements The water servicing requirements for the Bernard KDA have been calculated based on the recommended development concept by Urban Strategies dated May The proposed water demand calculations are shown in Attachment Methodology The InfoWater hydraulic model provided by Town has been used to analyze the water distribution system, and its ability to deliver the required demands at the appropriate residual pressures, including an allowance for fire flows. Per Town s design criteria, residential flows of 365 Lpcd and employment flows of 90,000 L/ha/day have been considered. The fire flow requirements for the mixed use high rise buildings were calculated based on FUS methodology (Refer to the attachment 5). The specific fire flow requirements will be refined when building floor plates are established, at the Functional Servicing Stage. Two pressure districts, Pressure Districts 7 and 8 were identified to service the study area. Based on the recommended development concept plan, potential proposed 300 mm KDA watermains were added to the model. The North East and TMIG PROJECT NUMBER MEMO - Background Servicing Review

3 MEMORANDUM PAGE 3 of 4 JUNE 13, 2017 South East quadrants would be serviced via PD7 watermains. The North West quadrant of the KDA would be serviced by existing PD 8. There were two possible options identified to service the South West quadrant. In Option 1, PD 7 mains would be extended to Canyon Hill Avenue along the proposed road and connected east of the PD 7/8 zone valve. In Option 2, PD8 mains would be extended along the proposed road and looped back to Canyon Hill Ave at Yonge St. Creating a Zone 8 loop would require a new local water main to be installed within the properties fronting Yonge Street, and could result in pressures above 700 kpa (100 psi). The pressure profiles resulting from the modelling indicate that the PD7 option is viable and is therefore recommended. Future system pressures were simulated based on Ultimate Buildout water demands and infrastructure for both the options. The Ultimate Buildout scenario was established at the time of the MESP, and demands for the Bernard KDA were updated based on the recommended development densities based on concept plan dated May This method accounts for the future intensification demands, based on the projected future population and employment statistics available at the time of Richmond Hill MESP. Attachment 6 shows the water system for the Bernard KDA. 3.4 Results Preliminary simulations indicate that there is capacity for the water distribution system to support the intensification of the study area. The model was simulated for Peak Hour demand and Maximum Day Demand with Fire flow scenarios. Results show that there is enough pressure available within the system to service the KDA. The pressure range available in the system is provided in Table 3.1. Table 3.1 Modelled Water Distribution System Information Modeling Scenario Minimum Water System Requirements Modeling Results within KDA Peak Hour Demand Maximum Day Demand plus Fire Flow Recommended Normal Pressures within the System = 275 kpa to 690 kpa Employment Fire flow requirements per Town of Richmond Hill, Q f = 185 L/s to 480 L/s System Pressure = 281 kpa to 713 kpa Available Employment Design Fire Flow = 285 L/s to 850 L/s Note: The specific fire flow requirements will be refined when building floor plates are established. Fire flows in the order of 300 L/s will likely be required, and watermains will be identified for potential upgrades as required. 4 Stormwater Management Analysis 4.1 Previous Richmond Hill Urban MESP Findings The capacity of the existing storm sewer network was analyzed using InfoSewer in the Richmond Hill Urban MESP. Based on the MESP, no issues were identified within the area of the Bernard KDA. 4.2 Recommended Criteria for Redevelopment The runoff from the development are to be controlled to the Town and TRCA standards as well as the recommendations from the Richmond Hill Urban MESP, the Oak Ridges Moraine Conservation Plan, and the Source Protection Plan. The recommended criteria for re-development from the Urban MESP are as follows: Volume Control: The minimum volume control criterion is on-site retention of the first 5mm of precipitation. If the redevelopment requires a pond, then the retention of the 25mm storm for 48 hours is required. Water Quality: The minimum water quality criterion is to implement Level 1 (Enhanced) water quality control. Water Quantity: The minimum water quantity criterion is to control post-development peak flows to predevelopment levels for all storms up to and including the 100 year. If the redevelopment is 5ha or greater and drains to the Don River watershed, then the quantity requirement is based on the unit flow relationship. Water Balance: At minimum, the post to pre-development water balance is required to meet the policies of the Oak Ridges Moraine Conservation Plan and the Source Protection Plan. Infiltration, evapotranspiration and runoff should all be assessed. TMIG PROJECT NUMBER MEMO - Background Servicing Review

4 MEMORANDUM PAGE 4 of 4 JUNE 13, 2017 Details of the stormwater management strategy for each proposed development will be determined during the development application process as a functional servicing report is required to demonstrate conformity to the Urban MESP as well as Town and TRCA standards. As per the Urban MESP, The FSR should provide details of the proposed on-site measures for quality and quantity control, and volume control through the use of feasible LID measures. The FSR storm drainage and SWM analysis should be completed in accordance with Town and TRCA standards. Minor system drainage design sheets in accordance with Town standards shall be submitted at the detailed site plan design stage to verify system capacity. 4.3 Results Drainage areas for the study area has been delineated based on the existing drainage pattern and the recommended development plan provided by Urban Strategies Inc. in May The approximate outlet location of each drainage area as well as the required storm sewers along the proposed roadways have also been identified and are illustrated in Attachment 7. Based on the proposed development plan, new roads are proposed to provide additional connections within the key development area. As a result, additional storm sewers will be required to safely capture the runoff from the roadways to an appropriate outlet and to provide safe access of the roadways. The proposed storm sewers will be required to be designed to convey the 5-year design storm frequency as per the Town s standards. The outlet locations identified have been determined based on existing drainage patterns and the existing outlet locations. Two new outlets are proposed to discharge directly into the nearby watercourse and two new connections to the existing storm sewers are proposed. The Richmond Hill Urban MESP dated May 2014 did not identify any capacity issues of the existing storm sewer network. Additionally, the drainage area and outlet locations have been delineated based on existing drainage patterns. Thus, through the implementation of the required SWM controls, the existing system should have sufficient capacity to convey the runoff from the roadways. 5 Conclusion Overall, the major infrastructure currently servicing the Bernard KDA appears to have the capacity to accommodate additional development. There are a few infrastructure upgrades required to servicing future development at this time, based on the capacities of the City s existing systems. These findings are in consistent with the findings of the Richmond Urban MESP. Once the site plan details are defined, a more detailed analysis of the serviceability will be refined. Local sanitary sewer, storm sewer, or watermain upgrades or network extensions are required, many of which are anticipated within planned future roads. TMIG PROJECT NUMBER MEMO - Background Servicing Review

5 Project: Date: 19-May-17 Bernard KDA Draft plan Wastewater flows Sanitary Flows Attachment 1 High Rise = 2.7 ppu, Low to Mid rise = 3.5 ppu Avg Residential Sanitary Flows = 365 LPCD Avg Employment Sanitary Flows = L/ha/day Parcel Number JOBS RES UNITS RES PPU Res Pop Res Flow Peaking Factor Peak Res Flow Emp Flow Total Peak Flow D/S Reach MH NE D 106 NE E SA3379 NW1 Omitted Omitted A - NW A SA3013 NW B SA3011 SE G SA E SA3382 SE F SA3124 SE G SA4817 SE G SA4817 SE F SA3124 SW C SA8668 SW C SA C SA6843 SW C SA8668 SW C SA8668 SW C SA8668

6 Attachment 2

7 Attachment 3 Reach ID MAIN ID From MH To MH Diameter Full Flow Total Flow Reserve Capacity % Reserve Capacity B SL3106 SA3011 SA % B SL3080 SA3012 SA % A SL3081 SA3013 SA % 1

8 Attachment 3 Reach ID MAIN ID From MH To MH Diameter Full Flow Total Flow Potential Reserve Capacity % Potential Reserve Capacity C SL8644 SA8668 SA % C SL8645 SA8669 SA % C SL8646 SA8670 SA % C SL8334 SA4758 SA % C SL4635 SA8296 SA % C SL5389 SA4759 SA % C SL4636 SA5445 SA % C SL4637 SA4760 SA % C SL1320 SA1207 SA % 2

9 Attachment 3 Reach ID MAIN ID From MH To MH Diameter Full Flow Total Flow Potential Reserve Capacity % Potential Reserve Capacity D % D SA % 3

10 Attachment 3 Reach ID MAIN ID From MH To MH Diameter Full Flow Total Flow Potential Reserve Capacity % Potential Reserve Capacity E SL3442 SA3378 SA % E SL3443 SA3379 SA % E SL3444 SA3382 SA % E SL3445 SA3119 SA % E SL3446 SA3156 SA % E SL3447 SA3157 SA % E SL3448 SA3158 SA % E SL3449 SA3159 SA % E SL3450 SA3160 SA % E SL3476 SA3161 SA % E SL3477 SA3393 SA % E SL3478 SA3394 SA % 4

11 Attachment 3 Reach ID MAIN ID From MH To MH Diameter Full Flow Total Flow Potential Reserve Capacity % Potential Reserve Capacity F SL3413 SA3124 SA % F SL3414 SA3364 SA % F SL3415 SA3365 SA % F SL3416 SA3366 SA % F SL3485 SA3367 SA % F SL3481 SA3397 SA % F SL3482 SA3398 SA % F SL3479 SA3395 SA % F SL2937 SA2856 SA % F SL2938 SA2855 SA % F SL2939 SA2854 SA % F SL2942 SA2853 SA % F SL4638 SA2851 SA % F SL3396 SA3348 SA % F SL3395 SA3347 SA % 5

12 Attachment 3 Reach ID MAIN ID From MH To MH Diameter Full Flow Total Flow Potential Reserve Capacity % Potential Reserve Capacity Yonge St SL4705 SA4815 SA % Yonge St SL4706 SA4816 SA % Yonge St SL4707 SA4817 SA % Yonge St SL0345 SA0341 SA % 6

13 RIDGESTONE DRIVE BROOKGREENE CRESCENT ROTHBURY ROAD LEYBURN AVENUE Bernard KDA - Sanitary Servicing Alternatives Attachment 4 LAREDO DRIVE LOYAL BLUE CRESCENT ALADDIN CRESCENT BROOKSIDE ROAD SILVERWOOD AVENUE SQUIRE DRIVE A 1 STANCROFT DRIVE ABITIBI STREET B D NAUGHTON DRIVE DEBONAIR STREET LANE N E BERNARD AVENUE CANYON HILL AVENUE C F YORKLAND STREET LORRAINE STREET JUSTUS DRIVE COOPERAGE CRESCENT Legend Sanitary Sewer Other Ex. Sewers LEONARD STREET Alternative 1 - Upsize the Ex Sewers Prop-San-sewers Name Alternative 2: -Extend new sewers along new east-west street -Connect to a new MH on the Regional Trunk Drainage Alternative 2 Alternative 1 Alternative 1 & 2 YONGE STREET Manhole Other Ex. Manholes 2 Alternative 1: -Upgrade sewer along west side of Yonge St -New sewer along east side of Yonge St. -Connect to Existing Regional MH NEWMILL CRESCENT ELMPARK COURT Prop - MH Alternative 2 - NEW Regional MH Local new MH Ex. MH Connect New/Upgraded Sewers to Ex. Reg MH

14 Project: Date: 19-May-17 Bernard KDA Draft plan Water demand Calculations Attachment 5 High Rise = 2.7 ppu, Low to Mid rise = 3.5 ppu Average daily demand (ADD) = 365 LPCD Maximum daily demand (MDD) = 545 LPCD Peak Hour demand (PHD) = 910 LPCD Parcel Number Parcel Area JOBS RES UNITS RES PPU Res Pop Res ADD Water Demands Res Res Emp DMD MDD PHD Total MDD NE NE NW1 Omitted Omitted Omitted NW NW SE SE SE SE SE SW SW SW SW SW

15 Fire Flow Calculation Fire Underwriters Survey Methodology Bernard KDA Development-Block SE4 Project: By: VP Date: 8-Jun-17 Checked: KCB Attachment 5 Step 1: Fire Flow Formula F= 220 * C * A 0.5 C= Construction Coefficient C= Wood Framing 1.0 Ordinary - Brick Walls, Combustible Interior 0.8 Non-combustible (metal structure, masonry or metal walls) 0.6 Fire Resistive A= Total Floor Area in sq.meters A= 30,000 m² Step 2: Reduction/Surcharge for Occupancy Non Combustible Content -25% Limited Combustible -15% Combustible 0% Free Burning 15% Rapid Burning 25% F= 30,484 L/min Charge= -15% Revised F= 25,911 L/min Step 3: Reduction for Sprinkler System The Revised F value may be reduced up to: 50% for a complete automatic sprinkler system 30% for a sprinkler system conforming to NFPA 13 Reduction= 60% (Note 1) Reduction= 15,547 L/min Step 4: Exposure Surcharges 0 to 3.0 m 25% 3.1 to 10 m 20% 10.1 to 20 m 15% 20.1 to 30 m 10% 30.1 to 45 m 5% Unpierced Party Wall 10% The sum of all exposures must be less than 75% Direction Distance Charge % North 45 5% South 45 5% East Party Wall 10% West Party Wall 10% Total Charge= 30% Exposure Surcharge= 7,773 L/min Step 5: Design Fire Flow Min 2,000 L/min; Max 40,000 L/min (rounded to 1,000 L/min) Revised F= 18,000 L/min Revised F= 300 L/s Note 1: Additional credit of 10% is applied because the water supply will be standard for both the system and the fire department hose lines. (per "Water Supply for Public Fire Protection, FUS 1999) G:\Projects\2016\ USI - Bernard KDA\Design\ Water-Wastewater calculations Fire Flow -Building 6/13/2017

16 BERNARD KDA - Water System Attachment 6 BERNARD AVENUE Legend Junction AVAIL_FLOW < 75 L/s L/s L/s L/s > 480 L/s TRH_WAT_Valves ValveType, Status!U Relocated Zone Valve, Proposed PresureDistricts DISTRICT 7 8 Pipe Ex Pipes Proposed Pipes Proposed Pipes - PD7 Extension KDA_Study_Area

17 Bernard KDA - Storm Drainage Plan Attachment 7 Legend SWM Drainage Area Bernard KDA Study Area Culvert SWM Facility Watercourse Existing Storm MH Proposed Storm Sewer Existing Storm Sewer Ownership Private Regional Municipal Town of Richmond Hill 1 2