PRELIMINARY MUNICIPAL SERVICING REPORT NORTHWOODS SUBDIVISION. Prepared for: North Grassie Properties Inc.

Transcription

1 PRELIMINARY MUNICIPAL SERVICING REPORT SUBDIVISION Prepared for: North Grassie Properties Inc. Prepared by: Stantec Consulting Ltd. 905 Waverley St. Winnipeg, MB R3T 5P4 July 2012 File:

2 SUBDIVISION Table of Contents 1.0 INTRODUCTION WATER SYSTEM WASTEWATER SEWER SYSTEM LAND DRAINAGE SEWER BACKGROUND DESIGN CRITERIA AND DETAILED ANALYSIS Retention Lakes Land Drainage Sewers... 6 LIST OF FIGURES Figure 2.1 Water Supply Concept Figure 3.1 Wastewater Sewer Concept Figure 4.1 Land Drainage Sewer Concept \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc i

3 1.0 Introduction This brief has been prepared for submission to the City of Winnipeg as a requirement of their development review and subsequent approval on behalf of the developer, North Grassie Properties Inc. The brief covers the conceptual servicing options for this proposed subdivision. The proposed development encompasses approximately 77.4 hectares and is ultimately bounded: - on the north by Gunn Road, - on the east by the Perimeter Highway, - on the south by a Hydro Transmission Line ROW and the Cordite Drain. - and on the west by a Hydro Transmission Line ROW. \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc 1

4 2.0 Water System The water service area is shown on Figure 2.1. The system will have two feedpoints that are located at: - Redonda Street and Paulley Drive off an existing 250 watermain, - Fairview Drive and Millbrook Road off an existing 150 watermain. The systems performance was analyzed under various operating conditions using EPA NET 2.0, a computer simulation program produced by the Environmental Protection Agency (EPA). For our analysis, the City of Winnipeg s Water and Waste Department provided us with simulated conditions at the above feedpoints that were inputted into our model. The simulated feedpoint pressures were representative of maximum day demand conditions in the distribution system. The following design criteria and assumptions were used in the analysis of the watermains: 1. Hazen-Williams coefficient of friction ( C value) for all pipe diameters was assumed to be Population based on 3.05 persons per single family dwelling unit and 2.30 persons per multi family dwelling unit. 3. The number of dwelling units served by each node was calculated based on the concept plan shown in Figure The average daily per capita consumption used was 270 L. 5. The assumed peak daily consumption for: - Commercial is 28,100 l/day/ha. - Industrial is 37,600 l/day/ha. 6. The maximum day demand used was 1.6 x average day rate. 7. The peak hour multiplier used was For analysis purposes, the watermains were assumed to be at a constant elevation considering the subdivision s ground elevations vary slightly. The watermain system was tied into feedpoint nodes where simulated hydrant flow test data was provided by the City of Winnipeg. 9. Hydrant losses were accounted for by calculating available fire flows using 25 psi as opposed to 20 psi. Based on the above conditions, the proposed watermain system can meet the required operating criteria of: \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc 2

5 Water System July A minimum pressure of 207 kpa (30 psi) under maximum hour consumption. - The minimum fire flow specified above at 140 kpa (20 psi) with maximum day consumption. Required City of Winnipeg design fire flows with maximum day demand on the system are to be 100 l/s or greater for single family, 200 l/s or greater for multifamily and 250 l/s or greater for commercial and industrial based on the FUS method. By connecting to the two feedpoints mentioned above, we are able to achieve the single family fire flow requirement. The northeast corner of the Development is planned to be multifamily (combination of 4- plexes and medium density 6 storey buildings). This location is the furthest from the feed points and therefore has the lowest available fire flow protection, which is approximately 110 l/s. Standard City of Winnipeg FUS design for these MF Buildings will not achieve the required 200 l/s fire flow in this area. City Engineers were consulted with to determine if a feeder main extension into east Transcona would improve the hydraulics in the area. They determined that it would only marginally improve the fire flow capacity as a result of the long distance between the development area and the existing feeder main network / pumping station. It was concluded that the high cost for little benefit would not be justifiable. It is possible to reduce the required fire flow in this MF area through building / site design adjustments. Some things to consider will be; building separation, building size, construction materials, possibility of sprinkler systems, fire walls, etc. The calculations will have to conform to the FUS (Fire Underwriters Survey) and will have to be reviewed and approved by City Engineers and the Fire Department. For example, a wood framed 4 plex unit with a 5000 sq.ft floor area with side separation of 3.1m 10.0m and rear/front separation of 10.1m 20m would require 150 l/s fire flow protection. By changing the construction to Ordinary (ie. Brick or masonry walls) the required fire flow protection drops to 100 l/s which we are able to achieve. If the above is satisfactory to the City Engineers and the Fire Department it will be critical for this requirement to be flagged with the property. We suggest that a caveat be placed with the properties specifying the need for alternate building / site design to meet the available fire flows. md \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc 3

6 3.0 Wastewater Sewer System The proposed development is located in a new proposed Sewer District north of the Transcona Sewer District that will discharge to a new 750 mm Interceptor sewer that will be extended north on Plessis Rd. from the intersection of Plessis & Devonshire. The proposed Interceptor would turn east on Gunn Rd. and terminate at Day St. North Grassie Properties will be responsible to extend a wastewater sewer from the Development and tie it into the Interceptor. This sewer district will be conveyed to the North End Pollution Control Centre via existing Interceptor Sewers. A schematic of the wastewater sewer system for this Development is shown in Figure 3.1. The design criteria below will be used to design wastewater sewer system for this Development: 1. Peak Design Flow = domestic sewage x peaking factor plus extraneous flow. The extraneous flows include groundwater infiltration and manhole cover inflow. 2. Domestic Sewage (Residential) Average Flow: 270 L/capita/day Peaking Factor: Harman s = /(4+p 0.5 ) Population/dwelling = 3.05 persons (single family) = 2.30 persons (multi family) Dwelling Density = based on single family lotting plan and densities provided by planners for Multi Family 3. Peak Commercial Flow: 28,100 L/ha/day Peak Light Industrial Flow: 37,600 L/ha/day 4. Extraneous Flow a) Groundwater Infiltration: 2200 L/ha/day b) Manhole Infiltration: 12 L/min/manhole Manhole Spacing: 1.6 Manholes/ha 5. Pipe selection was based on full flow pipe with Manning s N = and minimum velocity of 0.6 m/sec (2.0 ft/sec). Adequate pipe cover and slope will be demonstrated on the detailed design drawings. \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc 4

7 4.0 Land Drainage Sewer 4.1 BACKGROUND The proposed 77.4 hectare development is located within Area F of the Bunn s Creek Drainage Area. 4.2 DESIGN CRITERIA AND DETAILED ANALYSIS Retention Lakes The specific City of Winnipeg criteria guidelines applicable to the Retention Lakes are as follows: m lake rise for a 25 year storm (maximum). - Freeboard Elevation (0.90 m above 100 year level) - 4:1 side slopes below water and 7:1 side slopes above normal water level and 3.0 m horizontally into the water m water depth. The typical retention lake cross section is as follows: InfoWorks CS software will be used to simulate the City of Winnipeg 25 yr, 100 yr and the May 2010 design storms on the Retention Lakes and interconnecting pipe system to confirm the storage availability and operation of the system. \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc 5

8 Land Drainage Sewer July 2012 The retention lake will be modeled as storage nodes with 7H:1V side slopes from 0.43m below the normal water level up to 1.5 m above N.W.L. The N.W.L. elevation in the retention lakes will be maintained by a Weir in a Manhole. For this model, the retention lake and the interconnecting land drainage sewers were configured and run in the EXTRAN block and the subcatchments were run in the RUNOFF block. The Rainfall / Intensity Values for the 25 and 100 year storms were calculated by the following Intensity Duration Formulas: i 25yr = i 100yr = 72.5 (t + 9) ^ (t + 8) ^ (MacLaren 1974) (Acres 1978) In discussions with City Engineers, it was decided that two options would be evaluated for storm water discharge. The first option would look at discharging to the Cordite Drain either by gravity or pumping. The second option would look at discharging by gravity via an outfall pipe to the Floodway on the east side of the Perimeter Highway. These options will be evaluated in detail during the design phase of this project Land Drainage Sewers This section details the design criteria, parameters, and assumptions that will be used in the design of the land drainage sewers for this Development. The piped system will be designed using the Rational Design method and will be based on the following criteria: 5 year storm intensity equation I = 47.2/(t+8) > (MacLaren 1974). Pipe friction factor (Manning s n): (Concrete and PVC). Minimum full flow velocity: 3 ft /s. Maximum full flow velocity: 10 ft /s. The 1:5 year return frequency was used for the design of the storm sewer system. Runoff Design Criteria The rational design method was used to estimate rainfall runoff to be handled by the piped system: Q = CiA Where: md \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc 6

9 Land Drainage Sewer July 2012 Q = runoff (CFS) C = runoff coefficient i = rainfall intensity (in/hr) A = area (acres) The drainage catchments will include single family, multi-family and commercial zoning, which reflect runoff coefficients ( C values) of 0.50, 0.70 and 0.70, respectively. System Design Criteria The land drainage sewers in this subdivision will be designed as surcharged pipe systems that will accommodate the calculated runoffs. The surcharge level of the system will be designed to be at a minimum of 0.15m below the proposed gutter elevations. The Manning s Equation with an N = for concrete or PVC pipe will be used to determine pipe sizes and hydraulic losses within the system. md \\cd1201-f02\work_group\1168\active\ \northwoods\rpt_municipalservicing_northwoods_jul1912.doc 7

10 \\CD1201-F02\work_group\1168\active\ \\Precinct I Plan.dwg 11/3/ :10:38 AM PLAN No HYDRO TRANSMISSION LINE PLAN No HYDRO TRANSMISSION LINE PLAN No AC. POND 2.82± AC. GUNN ROAD RIGHT OF WAY 4 3 C2 block 1 block 4 block 6 block 13 block 16 block 15 block 5 block 7 block 2 block 3 block 8 block 9 block 11 block 12 block 25 block 26 block 35 block 27 block 28 block 36 block 32 block 34 block 29 block 23 block 40 ROAD 11 block 39 block 17 block 33 block 18 block 19 block 20 block 37 block 41 ROAD 9 block 31 ROAD 6 ROAD 20 ROAD 7 ROAD 21 ROAD 14 block 30 INTERSECTION SIGNALIZED ROAD 19 ROAD 16 ROAD 15 block 24 block 38 ROAD 25 ROAD 8 block 10 block 14 3 AC. POND block 43 block 42 ROAD 17 CMU N LEGEND: -PROPOSED WATERMAIN -EXISTING WATERMAIN CLOSED WATER CONTROL WORK (CORDITE DITCH) PLAN No ROAD 18 ROAD 22 ROAD 23 ROAD 16 PLAN No TEMPORARY ACCESS TO GUNN ROAD GUNN ROAD ROAD 24 CMU REDONDA STREET ROAD 2 ROAD 10 ROAD 1 HYDRO TRANSMISSION LINE ROAD 3 ROAD 4 block 21 block 22 CMU ROAD 5 ROAD 26 LAND TO BE ACQUIRED BY HMQ MANITOBA PROPOSED LOOPING EX 150 WM EX 150 WM PRECINCT I PLAN FIGURE 2.1 WATER SUPPLY CONCEPT ROAD 12 CERTIFICATE OF TITLE No REGISTERED OWNER: HMQ MANITOBA 5.32± AC. CERTIFICATE OF TITLE No REGISTERED OWNER: HMQ MANITOBA (SUBJECT TO RIGHT OF WAY) PERIMETER HIGHWAY

11 \\CD1201-F02\work_group\1168\active\ \\Precinct I Plan.dwg 11/3/ :10:38 AM PLAN No REGISTERED OWNER: HMQ MANITOBA CERTIFICATE OF TITLE No ± AC. RIGHT OF WAY block 16 7 AC. POND block 5 block 6 block ± AC C2 1 block 1 block 4 block 7 block 2 block 3 block 8 block 9 block 11 block 13 block 32 block 35 block 27 block 26 block 28 block 25 block 36 block 37 block 29 block 39 block 17 block 12 block 18 block 40 block 34 block 33 block 41 ROAD 9 block 31 ROAD 8 ROAD 6 ROAD 7 ROAD 14 block 30 ROAD 16 INTERSECTION SIGNALIZED ROAD 19 ROAD 15 block 10 block 14 block 24 block 38 3 AC. POND block 21 block 22 block 43 block 42 ROAD 17 ROAD 25 TEMPORARY ACCESS TO GUNN ROAD block 23 CMU GUNN ROAD GUNN ROAD N LEGEND: -PROPOSED WASTEWATER INTERCEPTOR SEWER -EXISTING WASTEWATER INTERCEPTOR SEWER -PROPOSED WASTEWATER SEWER HYDRO TRANSMISSION LINE PLAN No HYDRO TRANSMISSION LINE PLAN No ROAD 20 ROAD 21 CLOSED WATER CONTROL WORK (CORDITE DITCH) PLAN No ROAD 18 ROAD 22 ROAD 23 ROAD 16 PLAN No ROAD 24 CMU REDONDA STREET HYDRO TRANSMISSION LINE ROAD 11 ROAD 10 ROAD 12 ROAD 2 ROAD 3 ROAD 5 ROAD 4 CERTIFICATE OF TITLE No REGISTERED OWNER: HMQ MANITOBA (SUBJECT TO RIGHT OF WAY) PERIMETER HIGHWAY ROAD 1 ROAD 26 block 19 block 20 CMU PRECINCT I PLAN FIGURE 3.1 WASTEWATER SEWER CONCEPT LAND TO BE ACQUIRED BY HMQ MANITOBA

12 \\CD1201-F02\work_group\1168\active\ \\Precinct I Plan.dwg 11/3/ :10:38 AM PLAN No block 16 7 AC. POND 2.82± AC. GUNN ROAD RIGHT OF WAY C2 block 1 block 5 block 4 block 6 block 15 block 7 block 2 block 3 block 8 block 9 block 11 block 13 block 26 block 35 block 32 block 36 block 12 block 25 block 27 block 28 block 39 block 17 block 29 block 37 block 40 block 34 ROAD 11 block 33 block 41 ROAD 9 block 31 ROAD 6 block 38 ROAD 16 ROAD 14 INTERSECTION SIGNALIZED ROAD 19 ROAD 25 ROAD 8 ROAD 7 block 18 block 19 block 20 block 30 ROAD 15 block 10 block 14 block 23 block 24 block 43 block 42 ROAD 17 CMU N LEGEND: -PROPOSED LAND DRAINAGE SEWER -OUTFALL OPTION #1 -OUTFALL OPTION #2 HYDRO TRANSMISSION LINE PLAN No HYDRO TRANSMISSION LINE PLAN No CLOSED WATER CONTROL WORK (CORDITE DITCH) PLAN No ROAD 18 ROAD 24 3 AC. POND ROAD 20 ROAD 22 ROAD 23 ROAD 21 ROAD 16 PLAN No TEMPORARY ACCESS TO GUNN ROAD CMU GUNN ROAD REDONDA STREET ROAD 2 ROAD 10 ROAD 1 HYDRO TRANSMISSION LINE ROAD 3 ROAD 4 block 21 block 22 ROAD 12 CERTIFICATE OF TITLE No REGISTERED OWNER: HMQ MANITOBA TO FLOODWAY OUTLET TO CORDITE DRAIN PRECINCT I PLAN FIGURE 4.1 LAND DRAINAGE SEWER CONCEPT ROAD ± AC. CERTIFICATE OF TITLE No REGISTERED OWNER: HMQ MANITOBA (SUBJECT TO RIGHT OF WAY) PERIMETER HIGHWAY ROAD 26 CMU LAND TO BE ACQUIRED BY HMQ MANITOBA