DERRY GREEN BUSINESS PARK WATER AND WASTEWATER SERVICING AREA SERVICING PLAN

Transcription

1 DERRY GREEN BUSINESS PARK WATER AND WASTEWATER SERVICING AREA SERVICING PLAN Submitted to: Town of Milton Regional Municipality of Halton Submitted by: AMEC Earth & Environmental 3215 North Service Road Burlington, ON L7N 3G2 Tel: (905) Fax: (905) AMEC Project No.:

2 September, 2010 TABLE OF CONTENTS PAGE 1.0 INTRODUCTION WASTEWATER SERVICING ANALYSIS Design Criteria Wastewater Servicing Analysis Results Servicing Scheme System Overflow WATER SERVICING ANALYSIS Design Criteria Water Servicing Analysis Results Servicing Scheme PHASING CONSTRUCTION OF UNDERGROUND SERVICES SUMMARY LIST OF TABLES Table 1 Wastewater Benchmark Costs... 3 Table 1A Wastewater Servicing Analysis Phasing... 3 Table 2 South Halton Master Plan Update - Water Distribution System Connection Points for Milton Business Park Phase Table 3 Design Criteria Water Distribution System... 6 Table 4 Water Servicing Analysis Results... 7 Table 4A Water Servicing Analysis Phasing... 7 LIST OF APPENDICES Appendix A Appendix B Appendix C Appendix D Appendix E Appendix F Preferred Land Use Sanitary Sewer Design Figures and Calculations Water System Model Output Proposed Phasing Plan Interim Servicing - Wastewater System Overflow G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page i

3 1.0 INTRODUCTION water and wastewater services will require the extension of water distribution and wastewater collection facilities by the Region of Halton into the Study Area. The water and wastewater servicing requirements have been determined by the Region as part of the Water and Wastewater Master Plan Update, 2008 (Master Plan). Further, an Amendment to the Master Plan for the wastewater system to reduce the number of pumping stations has been undertaken. This was completed by AMEC on behalf of Halton Region and is presented in the EA Addendum to the South Halton Water and Wastewater Plan Update, Relocation of Pumping Station ID 5898, Given that the water transmission and wastewater collection facilities have been identified in the Master Plan and are being planned for requirements, AMEC has examined water and wastewater servicing based on the preferred land use option provided by the Study Team (refer to Appendix A). The process used in the preparation of the water and wastewater servicing plan is as follows: i) Water and wastewater models developed based on background information assembled as in the Background Report. ii) iii) Through consultation with the Region and the Consulting Engineer responsible for the Region of Halton Water and Wastewater Master Plans, key information, such as pumping station location, forcemain outlets, water pressure and flow, the water and wastewater models were calibrated for use. Analysis of the preferred land use option was undertaken and the output data provided to the Region of Halton for review. The Water and Wastewater Servicing Report, which follows, provides the details necessary to address servicing requirements for the. Construction of the water and wastewater infrastructure identified as the responsibility of Halton Region to service are contingent on the approval by Halton Region Council of an acceptable financial and implementation plan. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 1

4 2.0 WASTEWATER SERVICING ANALYSIS 2.1 Design Criteria Future peak wastewater flows were calculated based on an equivalent population density as identified in the Region of Halton Water & Wastewater Design Guidelines and the Town of Milton Derry Green Corporate Business Park Secondary Plan Options Report dated February A light commercial design flow of m 3 /ha/day was utilized in determining the required sizing of the proposed wastewater mains. The wastewater collection system has been designed based on an employment density of 45 jobs per hectare. The pumping station (ID 5898) has been designed based on 45 jobs per hectare. A common L/s/ha inflow/infiltration flow rate and a Harmon peaking factor were also used in assessing the system. Proposed drainage areas and corresponding road patterns are identified in Appendix A. The wastewater design calculation sheets are located in Appendix B. This information has been taken from the Addendum to the South Halton Water and Wastewater Plan Update, December For the purposes of this study, it has been assumed that the proposed Regional wastewater pumping station and associated works will be sized to accommodate the business park flows and will be installed prior to the construction of the wastewater mains servicing this area. The tentative timing for the construction of this pumping station and associated infrastructure as outlined by the documents and included in the and from the South Halton Water and Wastewater Master Plan Update Development Community Technical Workshop, dated June 2008, as amended, are: ID 5898 Pumping Station Fifth Line at South-West of Union Gas Corridor: 2010 ID 5894 ID 6112 ID mm to 600 mm diameter wastewater mains on Fifth Line from Main Street to PS ID 5898: 2010 Temporary forcemain from PS ID 5898 to existing trunk wastewater main on Bennett Avenue: 2010 Permanent forcemain from PS ID 5898 to proposed 525 mm wastewater trunk on Fifth Line: 2010 Dates are contingent on the approval of a Financial Plan by Halton Region Council for this area. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 2

5 2.2 Wastewater Servicing Analysis Results Appendix B illustrates the proposed wastewater collection system for the preferred road pattern. A summary of the unit costs for the wastewater system is provided in Table 1. The unit costs are based on the unit costs developed for the Water and Wastewater Master Plan Update, adjusted to 2010 values. Table 1 Wastewater Benchmark Costs Diameter 5 m Depth 10 m Depth 300 mm $446 N/A 375 mm $624 $2, mm $672 $2, mm $726 $2, mm $828 $3, mm $1,067 $3, mm $1,204 $3, mm $1,305 $3, mm $1,436 $3,806 The development of the will be phased and the Town of Milton has identified a phasing plan for the lands. The Phasing Plan is discussed in Section 4.0. Table 1A presents the cost of wastewater servicing by Phase, as represented on the Phasing Plan in Appendix D. The Sanitary Sewer Calculation Sheet used to derive these values is available in Appendix B. Table 1A Wastewater Servicing Analysis Phasing Phase Linear System < 375 mm > 375 mm Pumping Station Forcemain 1 $2,149,737 $12,996,628 $10,800,000 $4,200,000 2 $975,467 $999,950 $12,060,000 $4,244,000 3 $506,088 $ Servicing Scheme The wastewater service shall be constructed within existing or proposed rights-of-way in the standard location, as defined by Town of Milton and Region of Halton standards. The pumping station locations identified in Section 2.1 shall be located outside of the right-of-way on land to be acquired by the Region of Halton. The primary wastewater trunk system outletting to Pumping Station ID 5898 shall be constructed on Fifth Line. A schematic of the servicing plan is provided in Appendix B. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 3

6 The pumping station will require the construction of a discharge forcemain. The forcemain shall be located within the existing and proposed rights-of-way. For pumping station ID 5898, a temporary forcemain will be constructed in the Union Gas corridor and discharge to the wastewater main at Bennett Avenue. There is no standard location for forcemains and, therefore, each will be subject to a detailed assessment of optimal locations. The ultimate approval will be through Halton Region Halton Region requires the provision of an overflow to protect against basement flooding. The design of the overflow must consider the estimated elevation of the lowest basement, time for Operations to respond to a power outage or generator failure and location of an acceptable outlet. The provision of an overflow shall be addressed during detailed design. 2.4 System Overflow Halton Region policy requires the wastewater collection system to have a system by-pass in order to protect private property in case of back-ups. Generally, the most effective method of achieving a by-pass is to provide an outlet from the pumping station to a watercourse/pond. For Derry Green, the usual method is not easily achievable due to the depth of the pumping station and the watercourses within the area. Pumping Station ID 5898 is the outlet for all lands north of the utility corridor. The area has substantially different elevations, with the north and west areas in excess of m elevation and lands near Sixth Line at m elevation. Based on these constraints, by-pass for Pumping Station ID 5898 would need to be set at m (i.e. 3.0 m below the minimum floor elevation) assuming slab-on-grade construction. The watercourse within Derry Green Phase 1 which has the lowest creek elevation crosses Sixth Line south of the utility corridor and is at approximately 182 m. This does not enable an overflow to be constructed. Therefore, based on our review of the constraints in Derry Green, the following is recommended in order to achieve system by-pass: 1. Lands adjacent to Sixth Line shall be restricted to a first floor elevation of m. Development below this level can only be accommodated through wastewater pumping to the collection system, and will be the responsibility of the Owner. The Town of Milton has considered this and are prepared to work within the restriction. 2. A system overflow for lands north of Derry Road and for lands adjacent to Sixth Line may be provided through a piped system outletting to the Middle Tributary of Sixteen Mile Creek at Sixth Line, south of the Hydro Corridor. The outlet elevation shall be set at m, which is the 5 year Water Surface Elevation (WSEL). The cost for the overflow is estimated at $4,200,000. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 4

7 3. A pumping station overflow, which essentially protects the pumping station and lands from Derry Road to the Utility (Hydro) Corridor, shall be constructed south along Fifth Line through the Boyne Survey to Britannia Road and on Britannia Road to the Sixteen Mile Creek. The overflow has been designed to pass flows in excess of the system overflows, plus a factor of safety. The overflow is sized for 100 l/sec. This overflow may be sized to provide by-pass for Pumping Station ID 5069 proposed for Britannia Road in addition to Pumping Station ID The system by-pass for north of Derry Road should be in place when Phase 1 is available for development. The pumping station by-pass may be deferred until development occurs in the area serviced south of the Utility (Hydro) Corridor. A schematic of the System Overflows are provided in Appendix F. 3.0 WATER SERVICING ANALYSIS The water servicing was undertaken utilizing information for the developed as part of the Master Plan. The Region (and their consultants) provided AMEC with maximum daily operating pressures at four (4) perimeter connection points near the Derry Green Business Park. Derry Green will be serviced by connection points located in Region of Halton Zones ML4 (proposed) and ML5 (existing). The connection points are summarized in the following table. Table 2 South Halton Master Plan Update Water Distribution System Connection Points for Milton Business Park Phase 2 Perimeter Connection Point Location Connection to the existing 900 mm feedermain at James Snow Parkway and Main Street Connection to the existing 900 mm feedermain at 4th Line and Derry Connection to the future 900 mm feedermain at the future booster pumping station at 4th Line and Louis St. Laurent Avenue Connection to the future 900 mm at 6th Line and Derry Road Zone Maximum Daily Operating Pressure (psi) Proposed Completion Date The business park development areas for the looped area (Fourth Line, Derry Road, Fifth Line, Main Street) will be serviced by the Zone ML5 water distributions system, while the development areas south of Main Street will ultimately be serviced by Zone ML4 water distribution system. The areas serviced by the Zone ML4 and ML5 water distribution systems are presented in Appendix C. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 5

8 Watermains identified in the Master Plan for include the following: ID 5860 ID 5861 ID 5862 ID 5863 ID 5864 ID 3846 ID mm watermain on Louis St. Laurent Avenue from Fourth Line to Fifth Line and north on Fifth Line to Clark Boulevard: mm watermain on Fifth Line, from Clark Boulevard to approximately 2300 m north: mm watermain loop through : mm watermain on Fifth Line from Derry Road to Main Street: mm on Main Street from Fifth Line to Fourth Line: mm watermain on Derry Road from Fifth Line to Fourth Line: mm watermain on Derry Road from Trafalgar Road westerly: 2013 As can be determined, a majority of the projects are scheduled for construction commencing in Dates are contingent on the approval of a Financial Plan by Halton Region Council for this area. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 6

9 3.1 Design Criteria The following design criteria have been utilized in the hydraulic modeling: Table 3 Design Criteria - Water Distribution System Operating Pressures Maximum daily flow conditions 350 kpa (50 psi) to 550 kpa (80 psi) MOE Peak hour not less than 275 kpa (40 psi) Region of Halton Maximum pressure 690 kpa (100 psi) Region of Halton Simultaneous maximum day and Region of Halton not less than 140 kpa (20 psi) fire flow Equivalent Population Density Light Commercial Areas 45 persons/ha (12.375m 3 /ha/day) Region of Halton Demand Average Day Service Demands 275 L/person/day Region of Halton Maximum Day Factor 2.25 Region of Halton Peak Factor 2.00 Region of Halton Fire Flows (As per Water Supply for Public Fire Protection, Fire Underwriter s Survey, 1999) Undeveloped Commercial Area 250 L/sec As required by the Region of Halton, the minimum watermain pipe diameter specified was 300 mm, and hydrants are to be located at maximum 100 m intervals. 3.2 Water Servicing Analysis Results AMEC created the model using Infowater 5.0, and the operating pressures and available fire flows determined by the model for this report were run for a steady state scenario at the maximum daily operation pressure of the existing water system. The modeling results are provided in Appendix C. The modeling of the water system has been completed for system pressures using average day, maximum day and peak hour as well as fire flow. Figures 3 and 4 illustrate the results. The output indicates the proposed system will meet the water supply requirements of the Study Area. A summary of the costing for water servicing to is provided in Table 4: Table 4 Water Servicing Analysis Results Diameter Total Length Unit Cost 300 mm 10,763 m $ mm 3,300 m $ mm 7,100 m $1, mm 2,700 m $2,128 G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 7

10 As discussed previously, the development of shall be phased. The watermain cost by phase is presented in Table 4A, as represented in the Phasing Plan in Appendix D. Table 4A Water Servicing Analysis Phasing Phase Piping Local Piping Region 1 $4,318,380 $7,926,336 2 $3,074,693 $12,483,950 3 $598,455 It is understood that Piping Local refers to all watermains used entirely for localized areas sized at 300mm. 3.3 Servicing Scheme The water services shall be placed within existing or proposed rights of way in the standard location as defined by the Town of Milton standards. The Region of Halton has identified two (2) 750 mm diameter watermains for the Derry Green Business Park area on Fifth Line. The right of way width for Fifth Line is proposed to be 30 m. Based on this right of way width, the 750 mm diameter watermains can be accommodated within the right of way, in accordance with Figure 3.1. The separation from the wastewater and stormwater mains will need to affect a minimum separation of 2.5 m, vertically and horizontally, to meet MOE standards. The Region of Halton Development Charges Policy identifies watermains 400 mm and greater as Regional facilities. All other watermains shall be constructed as part of development works. 4.0 PHASING The development of lands within the may proceed as services become available. To that end, the Town of Milton has adopted a Phasing Plan which suggests the development of three (3) phases. Phase 1 includes lands bounded by James Snow Parkway on the west, the Utility (Hydro) Corridor on the north and lands fronting on Fifth Line from the Union Gas Corridor to the south limit of. The Phase 1 land area is ha. Phase 2 includes lands bounded by the east limit of the Business Park, Phase 1 lands on the west, and the Utility (Hydro) Corridor on the north, and to the north limit of the Union Gas Corridor. The Phase 2 land area is ha. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 8

11 Phase 3 includes the remaining lands north and east of the Utility (Hydro) Corridor and south of the Union Gas Corridor. The ultimate servicing will not be available for Phase 1, therefore, in order for these lands to proceed, initial servicing works by Halton Region will be required. The Phasing Plan and associated areas are provided in Appendix D. The following tables present modified water and wastewater programs; showing updated project descriptions, original 2007 Master Plan budgets, as well as estimated new budgets. Water ID # Description Zone mm Main St. JSP to Fifth Line Zone mm Fifth Line Main St. to Clark Rd. Zone mm Fifth Line Clarke Blvd. to approx m north Zone mm Fifth Line / Derry Loop Zone mm - Derry Rd. Fourth Line to Fifth Line Zone mm Louis St. Laurent Fourth Line to Fifth Line; and Fifth Line Louis St. Laurent to Clarke Blvd. Zone mm Derry Road - Fifth Line to Trafalgar Road Costs Currently in the Budget Master Plan 2009 Budget Year Value Year Value AMEC ASP 2008 $2,540K $2,394K 2008 $3,998K $3,055K 2016 $4,331K $3,798K 2016 $3,928K $2,940K Design 2011 $2,835K $2,477K 2013 $6,031K $5,476K On an interim basis, in order to provide water servicing to the, Projects 5864, 5863 and 3846 should be implemented. These projects provide a looped Zone ML5 system to the Business Park. In addition, Halton Region is providing for Projects 5861 and 5862, which is the Zone ML4 loop for the Business Park. There is no current Zone ML4 supply identified until 2011 (ID 5860). In order to service Derry Green at this time, an interconnection between Zone ML5 and Zone ML4 is required. The optimum location for the interconnection is on Derry Road at Fifth Line, between Projects 5863 and For Derry Green to utilize Zone ML5 supply for Zone ML4, system pressures should be reduced to Zone ML4 levels and two pressure reducing valves (PRV) are required to regulate pressures in the system. The PRV will be set at 80 psi to regulate system pressures to Zone ML4. Appendix C includes the system pressures for the interim condition. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 9

12 Wastewater ID # PHASE New PHASE 1 TOTAL * 5897* 5069* New* New* D Design C Construction Description 375 mm WWM on Fifth Line from Main St. to Trudeau Dr.; 450 mm WWM on Fifth Line from Trudeau Dr. to Derry Rd. W. (MIL); & 600 mm WWM on Fifth Line from Derry Rd. to new PS (ID 5898) New 25 MLD wastewater pumping station on Fifth Line approx. 750 m south of Derry Rd. West (MIL) System overflow for new pumping station (IPFS #5898) Phase mm Temporary WWFM on Union Gas ROW from Fifth Line to Ex. Trunk Sewer at Bennet Blvd. Permanent 2x200 mm WW Forcemain from new PS (IPFS #5898) to Fifth Line (MIL) 675 mm WWM on Fifth Line from PS (IPFS #5898 to Louis St. Laurent (include the connection of the permanent FM (IPFS #5899) (MIL) 675 mm WWM on Louis St. Laurent from Fifth Line to James Snow Parkway (MIL) 675 mm WWM on James Snow Parkway from Louis St. Laurent to Britannia Rd. (MIL) 675 mm on Britannia Rd. from James Snow Parkway to PS (IPFS #5069) (MIL) New 52 MLD sewage pumping station on Britannia Rd. approx. 300 m west of Third Line (MIL) System overflow for new pumping station (IPFS #5069) System overflow for new pumping station (IPFS #5898) Phase 2 2x400 mm WW Forcemain from new PS (IPFS #5069) to R. R. 25 (MIL) Decommission temporary FM (IPFS #6112) Halton Region Budget Costing Year Value Year Value $129K (Design) $461K (D) $173K (D) $233K (D) $996K (D) $1,690K (D) $1,031K (D) $1,166K (Const.) $4,144K $1,557K $2,099K $8,966K $1,716K $864K $1,800K $5,808K $6,853K $1,000K AMEC ASP 2010 $5,579K $10,800K $4,200K $4,200K $120K $24,899K $2,095K $2,361K $6,330K $7,728K $12,060K $304K $2,000K $4,124K $1,000K * These projects shall impact servicing for Boyne Neighbourhood as well as. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 10

13 In order to provide service for Phase 1 of the, Projects 5898, 6112, 5899, 5894 and the system overflow are required. These projects will provide approximately 187 l/s of wastewater capacity for the. The lands identified as Phase 1 have a capacity requirement of l/s. This calculation is based on the need of 0.9 l/s/ha of wastewater capacity. For all of the Phase 1 lands to be included for development, a temporary sanitary sewer will be required on Louis St. Laurent Avenue from Fourth Line to Fifth Line, and on Fifth Line from Louis St. Laurent Avenue to Pumping Station This temporary sanitary sewer will utilize capacity at Pumping Station 5898 until such time as the gravity system from south of the Union Gas corridor to the future Britannia Road Pumping Station (Halton Region ID 5069) is constructed. At that time, the temporary sanitary sewer will be abandoned and service connections will be connected to the gravity system, Project 5066, 5067, 6116 and It is noted that the temporary system will not be constructed by Halton Region as the wastewater mains are less than 375 mm diameter. In addition, the routing of the temporary sewers shall be developed in consultation with the Town and Region to ensure corridors are retained for the future ID 5066 and ID 6116 which form the trunk system. A schematic of the temporary wastewater system is provided in Appendix E. For Phase 2 and Phase 3 to move ahead, Projects 5066, 6116, 5064 and 5067 are required. In addition, the gravity sewer on Britannia Road, Project 5897, pumping station 5069 and associated forcemain will also be required to enable the ultimate development of Derry Green. These projects are currently scheduled for CONSTRUCTION OF UNDERGROUND SERVICES The water and wastewater servicing for the will be constructed utilizing conventional open cut methods. Excavation by open cut shall be undertaken in accordance with OPSS 514 Construction Specification for Trenching, Backfilling and Compacting and the Ontario Occupational Health and Safety Act, R.S.O and Ontario Regulation 213/91. Although a geotechnical investigation was not undertaken, it is expected that rock will be encountered for some linear services as well as the Pumping Station 5898, OPSS 515 Construction Specification for Rock Excavation for Pipelines, Utilities and Associated Structures in Open Cut, shall govern. The has significant National Heritage features. The area is traversed by three watercourse and the temporary forcemain from Pumping Station 5898 to Bennett Avenue traverses one watercourse, as well as a hedgerow and a swamp area east of James Snow Parkway. The construction method used through National Heritage lands shall be determined during detail design, in consultation with the Town of Milton, Halton Region and Conservation Halton. Generally, an attempt should be made to avoid the Natural Heritage lands where possible. If this is not possible, a requirement to use trenchless technology (i.e. tunneling, jack and bore, etc.) and maintain a minimum setback from the features should be proposed. G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 11

14 Any construction through lands regulated by Conservation Halton through Ontario Regulation 162/06 will require a permit from Conservation Halton. This includes the Union Gas corridor which has been designated as an Environmental Linkage Area. 6.0 SUMMARY The Water and Wastewater Servicing for the has been prepared based on the preferred land use as developed for the Secondary Plan. The employment density used for the study was 45 person per hectare. The basis of the water and wastewater design is from the Halton region Water and Wastewater Master Plan Update, 2008 as amended by the EA Addendum to the South Halton Water and Wastewater Plan Update, Relocation of Pumping Station ID 5898, The wastewater system Phase 1 design and construction reflected in Figure 1 is proposed for the, at a cost of $24,899,000. The water system design reflected in Figure 2, for all three (3) phases is proposed for the Derry Green Business Park, at a cost of $28,402,000. The project phasing has been developed to utilize existing capacity in the wastewater system. This strategy will enable the development of ha in Phase 1, subject to construction of facilities under design by the Region. PDS/kf G:\Work\107134\Corr\Report\ServicingPlan\10-12 Text.docx Page 12