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HomeMy WebLinkAboutDTS-09-116 - Class Environmental Assessment - Springdale sanitary pumping station replacementJ KITC~~R De~elopment& Technical5ervrces REPORT T0: Development and Technical Services Committee DATE OF MEETING: August 10, 2009 SUBMITTED BY: K. Grant Murphy, P.Eng., Director of Engineering Services PREPARED BY: Kevin Mick, P. Eng., Design and Approvals Engineer WARD(S) INVOLVED: Ward 1 DATE OF REPORT: July 31, 2009 REPORT NO.: DTS 09-116 SUBJECT: SPRINGDALE SANITARY PUMPING STATION REPLACEMENT -CLASS ENVIRONMENTAL ASSESSMENT (EA) STUDY RECOMMENDATION: THAT the Springdale Sanitary Pumping Station Replacement Class Environmental Assessment Report prepared by MTE Consultants Inc., dated July 2009 be received; and That the Springdale Sanitary Pumping Station Replacement Class Environmental Assessment Report be filed with the Ontario Ministry of the Environment for the mandatory thirty (30) day review period as required by the Environmental Assessment Act; and further; That staff be directed to commence the implementation of the recommendations of the Class EA, following the thirty (30) day mandatory review period and Ontario Ministry of the Environment acceptance of the study, through the Lift Station Replacement Account. EXECUTIVE SUMMARY The City initiated a Class Environmental Assessment study in 2008 to explore alternatives and prepare a preliminary design that addresses the operational issues that currently exist at the Springdale Sanitary Pumping Station (SPS). The study explored various solutions and evaluated each on defined criteria to determine a preferred alternative. The preferred alternative for the Springdale SPS is Alternative 3 -Gravity Sewer from Springdale Drive to General Drive. The main features of this alternative are the installation of a new gravity sewer using trenchless technologies, the removal of the existing SPS and the abandonment of the existing forcemain. io-i BACKGROUND: The Springdale Sanitary Pumping Station (SPS) is located at 8 Springdale Drive in the City of Kitchener. Springdale Drive is located in the City of Kitchener, in the north-eastern reaches of the City limits bordering the City of Waterloo. The Springdale SPS was constructed in the early 1960's to service Springdale Drive, a portion of Lang Crescent, a portion of Bridgeport Road and Horizon Court. The catchment area covers approximately 17 ha primarily comprised of residential zoning. The Springdale SPS is located within hazard land zone. The hazard zone is generally located between Springdale Drive, Lang Crescent and General Drive and is a mature forested area with a creek running through it. The station is comprised of prefabricated steel or "canned" pumping station with air operated sewage ejector pumps. Access to the pumping station is via a hatch through the top of the station. The station consists of an upper dry section and a lower wet well which houses the ejectors. The station is a vertical steel tube with access ladder and ventilation ducts. This station does not have standby power but could be configured to operate on temporary standby power. Sewage pumping stations of this nature were common in the 1960s and 1970s but are generally not constructed today. Many aspects of the station do not meet the City's current design standards for sewage pumping stations. City staff have noted some of the following issues associated with the Springdale SPS: the presence of grit, gravel and grease in the influent coming from the station, the existing pump has a very small operating range, sewage regularly backs up into the manhole on the street and there is no generator for operations during power failure. The lower wet well section is likely full of sludge and should be cleaned out. However, access to the lower section is very constrained and the deteriorated condition of the steel chamber won't permit safe entry and re-sealing of the lower compartment. As a result of the above mentioned issues, it is not possible to properly maintain the station. If the station fails to operate and repairs and mitigation measures cannot be implemented in time, the result would be a discharge of sanitary effluent to the nearby creek and eventually Laurel Creek and the Grand River leading to fines from the Ministry of the Environment. Due to the operational deficiencies identified at the Springdale SPS, the City has initiated a Class Environmental Assessment for the replacement or removal of the pumping station. REPORT: The City initiated a Class Environmental Assessment study to explore alternatives and prepare a preliminary design that addresses the operational issues that exist at the Springdale SPS, in a manner that complies with Ontario's Environmental Assessment Act. A project team was formed and comprised of City staff and Consultant staff with expertise in different fields, such that the project could be evaluated from multiple standpoints. The main objective of the study is to determine a preferred option for Springdale SPS with respect to operational issues, while taking into account: • Natural and physical components of the environment • Affects on residents and neighbourhoods Costs io-2 • Operations and maintenance • Constructability • Land requirements • Ability to Implement The Municipal Class Environmental Assessment Document (June 2000, as amended in 2007) defines "alternative solutions" as: "feasible alternative ways of solving an identified problem (deficiency) or addressing an opportunity, from which a preferred solution is selected". Based on the opportunities and constraints analysis, alternative solutions were identified and evaluated on project-specific evaluation criteria which covered four criteria categories as follows: • Technical environment • Natural environment • Social/Cultural environment • EconomiclFinancial environments • Legal/Jurisdictional environments Alternatives Solutions The following alternative solutions were identified as being feasible ways of addressing the operational and maintenance issues associated with the pumping station. Alternative 0 - Do Nothing As part of the Class EA process, the "Do Nothing" alternative solution must be considered. For this project, "Do Nothing" would involve leaving the existing pumping station in place with no upgrades. Alternative 1 -Replace Existing Station and use Existing Forcemain This alternative involves: • Existing pumping station on Springdale Drive to be replaced with a new station • New pumping station will utilize new pumping technologies increasing the station footprint and changing the layout • New station will include standby power • Preliminary construction cost - $900,000 Alternative 2A -Replace Existing Station and Install a New Forcemain from Lanq Cr. to Hnri~nn Ca This alternative involves: 10-3 • Existing forcemain that runs to Hammel would be abandoned and the new forcemain routed to Lang Cr. at Horizon Ct. • Existing pumping station on Springdale Drive to be replaced with new station • New station will utilize newer pumping technologies increasing the station footprint and changing the layout • New station will include standby power • Preliminary construction cost - $1,050,000 Alternative 2B -Replace Existing Station and Install a New Forcemain from Leander PI. to Hamel ~t This alternative involves: • Existing forcemain that runs to Hammel would be abandoned and the new forcemain routed along Lang • Existing pumping station on Springdale Drive to be replaced with a new station • New pumping station will utilize newer pumping technologies increasing the station footprint and changing the layout • New station will include standby power • Preliminary construction cost - $1,100,000 Alternative 3 -Gravity Sewer from Springdale Dr. to General Dr. (Preferred Alternative) This alternative involves: • This option would eliminate the need for a pumping station on Springdale Drive • The gravity sewer would be installed utilizing trenchless technology to minimize disruption to natural area • Easements from two private property owners would be required for the new sewer alignment • The existing pumping station would be removed completely • The existing forcemain would be abandoned in place • Preliminary construction cost - $450,000 Each of the above alternatives were evaluated based on their benefits in the five criteria categories (technical, natural, social/cultural, economic/financial and legalljurisdictional) and were rated numerically to determine the preferred solution. Using the numerical ratings the preferred solution for Springdale Sanitary Pumping Station is Alternative 3 -Gravity Sewer from Springdale Dr. to General Dr. This alternative provides the following benefits: • Improves the long term environmental impact since it eliminates the potential for sewage overflow into the creek during extreme wet weather or station failure • Improves the aesthetics of the neighbourhood as it eliminates the need for any above ground structure 10-4 • Lowest cost when taking into account capital, operation and maintenance costs since there is no pumping station to construct andlor maintain • Very low operation and maintenance requirements Proposed Sequence of Implementation City staff is proposing the following sequence for the implementation of the recommendations: • Completion of 30-day review • Easement acquisition • Detailed design • Permitting • Construction of new gravity sewer (Late 2009) • Removal of existing pumping station and abandonment offorcemain FINANCIAL IMPLICATIONS: Work completed to date on the Class EA has been accommodated in the Lift Station Replacement Account. The estimated cost of implementing recommendations of the study is $500,000. This amount includes construction costs and consulting fees, but does not include cost associated with easement acquisitions. The funding required for this work would also be funded from the Lift Station Replacement Account. The Lift Station Replacement Account was created to address replacement and upgrades associated with sanitary pumping stations that occur on an ongoing basis. This includes station replacement, new pumps and forcemain replacements. Each year, funds are allocated to this capital account in order to pay for these works. COMMUNICATIONS: A Notice of Commencement was published in the KW Record and was sent to a mailing list of interested individuals. Two Public Information Centres (PIC) were held as part of this project. The first PIC was held in January 2009 and the second in June 2009. The PIC's were advertised through newspaper and invitations were delivered to area residents and businesses. The first PIC wash held at Bridgeport Public School and the second PIC was held at City Hall. Input was also solicited from various utilities and government agencies through written correspondence and telephone conversations. 10-5 CONCLUSION: The completion of the Springdale SPS Class Environmental Assessment study has established a preferred alternative to address the operational and maintenance issues that exist the station. The preferred alternative is identified as Alternative 3 -Gravity Sewer from Springdale Dr. to General Dr. The main features of this alternative are the installation of a new gravity sewer using trenchless technologies, the removal of the existing SPS and the abandonment of the existing forcemain. Timing for the implementation of the recommendations will commence upon completion of the thirty (30) day mandatory review period and Ontario Ministry of the Environment acceptance of the study. ACKNOWLEDGED BY: Jeff Willmer General Manager, Development and Technical Services 10-6 E.0 EXECUTIVE SUMMARY AND RECOMMENDATIONS E1.0 Executive Summary In September 2008, the City of Kitchener initiated a Schedule "B" Class Environmental Assessment Study for the replacement and/or modernization of the existing Springdale Sanitary Pumping Station ASPS) located beside a GRCA regulated area. The Terms of Reference for this project were developed by the City and MTE Consultants Inc. was engaged to assist in completing the study. The Study Area for this Class EA project consists of the Springdale Sanitary Pumping Station (SPS) located at 8 Springdale Drive in the City of Kitchener and its associated sanitary catchment area located in the north-eastern reaches of the City of Kitchener limits bordering the City of Waterloo. The Springdale SPS was constructed in the early 1960's and is in a deteriorating condition. Minimal information is available regarding the initial design and construction of the existing station. The pumping station lacks emergency backup power allowing for the potential of a spill-over into the nearby creek. The pumping station is a continuing maintenance concern and because of the age, deteriorated condition and design of the station proper maintenance and repair is no longer possible. The Municipal Class EA addresses the following problem statement: "The Springdale Pumping station was installed in the early 1960's utilizing now out of date pumping technology. The station is a constant maintenance concern as it is subject to repeated failures and replacement parts for the station are no longer available for purchase. " The primary objective of this Class EA Study is to identify the Preferred Alternative for upgrade or replacement of the existing Springdale SPS. The intent of this Class EA Study is to identify opportunities and constraints as they relate to the natural and physical environment, and prepare a Functional Design of the selected Preferred Alternative for completion of the project. Five alternatives were developed for consideration and were presented for comment at the first Public Information Centre on January 20, 2009, including: Alternative 0: Do Nothing. Alternative 1: Replace existing pumping station and use existing forcemain. Alternative 2A: Replace existing pumping station, abandon existing forcemain and install new forcemain from the station to Lang Crescent at Horizon Court. Alternative 2B: Replace existing pumping station and install new forcemain to Leander Place at Hamel Street. Alternative 3: Construct a new gravity sewer from Springdale Drive to General Drive, remove the existing pumping station completely and abandoned the existing forcemain in place. io-~ An evaluation matrix (Appendix J) was developed to evaluate each alternative according to the following criteria: Natural Environment (Laurel Creek Watershed, aquatic and terrestrial species, mature trees and vegetation); Social/Cultural Environment (land use and property impacts, public acceptance); Economic/Financial (capital and maintenance costs); Legal/Jurisdictional; and, Technical (approvals, ability to implement and long term effectiveness). Based on the evaluation of the alternatives considered and comments received at the first Public Information Centre, the project team concluded that Alternative 3 (construct a new gravity sewer from Springdale Drive to General Drive) is the Preferred Alternative. Alternative 3 best meets the needs of eliminating the existing out of date Springdale SPS while balancing and mitigating the requirements of the natural environment, socio-economic environment and minimizing the capital construction and ongoing maintenance costs. A Functional Design of the Preferred Alternative was prepared and was presented at a second Public Information Centre on June 18, 2009. A preliminary construction cost estimate for the preferred solution was completed. The construction costs were estimated to be approximately $471,500 dollars, excluding engineering fees. E2.0 Recommendations Based on the results of this Class EA Study, the following are recommended: 1. The existing Springdale Sanitary Pumping Station should be decommissioned by completely removing the pumps, piping, and steel housing. The existing forcemain should be capped at both the inlet and outlet ends. 2. The Functional Design of the Preferred Alternative, Alternative 3 (Figure 3.3) should be used as the basis for final design and construction of the new 250 mm diameter gravity sanitary sewer from Springdale Drive to General Drive. 3. The construction of the gravity sewer should be completed using trenchless technology: horizontal direction drilling (HDD) or Auger Boring, to minimize impacts to the natural forested area, creek and local residents. 4. Due to the sensitive nature of the construction area and the degree of precision required to drill on grade and on line, the following is recommended: a. An experienced and specialized trenchless contractor should be selected to complete the works. b. A Geotechnical Baseline Report (GBR) be included as part of the Contract Documents. io-s 5. The alignment of the gravity sanitary sewer runs through a mature forested area primarily owned by the City. However, two sections of the alignment at the downstream end, near General Place, run directly through a GRCA regulated area and private property thus, a GRCA Fill Permit, an agreement with the land owners and an easement through this area needs to be obtained prior to construction. 6. A Stage 2 archaeological assessment must be conducted at any access pit locations that fall within areas of archaeological potential. This work must be done in accordance with the Ministry of Culture draft Standards and Guidelines for Consultant Archaeologists (Ministry of Culture, 2006). 10-9