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HomeMy WebLinkAboutINS-11-071 Sediment Removal PartnershipREPORT T0: Community and Infrastructure Services Committee ' DATE OF MEETING: September 12, 2011 SUBMITTED BY: Grant Murphy, Director of Engineering, 741-2410 PREPARED BY: Nick Gollan, Manager, Stormwater Utility, 741-2422, and, Melissa Ryan, Design and Construction Project Manager, 741-3400 ext.3173 WARD(S~ INVOLVED: 9 DATE OF REPORT: August 31, 2011 REPORT NO.: INS 11-071 SUBJECT: Victoria Park Lake Sediment Removal Partnership with Region of Waterloo RECOMMENDATION: For information BACKGROUND: Victoria Park Lake is an outlet-controlled pond on Schneider Creek which was created as part of the original park development more than 100 years ago. Nestled at the heart of downtown Kitchener's crown jewel, it serves as an important recreational and visual resource for park visitors. As a result of longstanding concerns regarding the water quality in the lake as well as sediment accumulation and subsequent removal, a Class Environmental Assessment was initiated in 2008 to investigate opportunities to address the water quality and minimize sediment accumulation and costly sediment dredging. The Class EA study explored five (5) alternatives for the lake as well as separate alternatives for the upstream watershed areas (refer to report DTS 09-096). The preferred alternative for the Victoria Park Lake is Alternative 3 -Reconfigure Lake to improve Function. The main features of this alternative are deepening the Lake and constructing a sediment forebay at the upstream end of the Park to minimize sediment from settling in the main portion of Victoria Park Lake. The general configuration of the Lake will be maintained. The Class EA Study Report was received and approved by Council on June 15th, 2009 (refer to DTS-09-096 Report). The first phase of the project includes the detailed design of the Victoria Park Lake improvements, and this was started in the early spring of 2011. Stantec Consulting is completing the design of this project and construction is anticipated to begin in late 2011 with work continuing in 2012, pending agency approvals. The total project cost for the Victoria Park Lake Improvements is estimated at $15.6 million including upstream works. Approximately $5.7 million to $7.6 million (refer to 2010 Budget Issue Paper 44) of this cost was estimated for sediment removal and disposal, between 40% IF1 - 1 1 Staff Re ort p I~t`r~.~-~~,i~iER ~nfrastrurture Servrces Department www.kitthenerta and 50% of the total cost estimate. Given that this is a significant component of the project, sediment disposal alternatives were reviewed early in the detailed design stage of this project. REPORT: Early in the detailed design stage of the project, the City and the retained consultant agreed to investigate various disposal alternatives for the sediment being removed from Victoria Park Lake and explored these potential approaches with Region of Waterloo staff. The scope and volume of material stemming from this project represented an opportunity to investigate a long term solution for this type of material. As part of the detailed design work, additional analysis was completed to more precisely determine the quality of the sediment and the amount or volume required to be removed. This work was completed during April and May 2011 and included mapping the lake bottom and shoreline in order to quantify the volume of sediment. Approximately 50,000 tonnes of accumulated sediment will need to be removed from the lake as well an additional 25,000 tonnes of native material (material below the existing lake bed) in order to improve the water quality of the lake and address sedimentation in the lake. Also 17 sediment samples were tested and analyzed which confirmed that the sediment is marginally contaminated, as compared to the limits established by the Ministry of the Environment. This requires the sediment to be disposed of at a landfill. This sediment chemical characterization has also determined that it meets the requirement for Daily Cover standards as per the Region of Waterloo "Request for Waste Disposal Approval" policy. The Region of Waterloo recognizes that the volume of sediment and soil from stormwater management facilities in addition to soil from other sites (i.e. brownfield sites, construction waste materials, etc.) represent a challenge to their landfill site capacity and expressed an interest in seeking innovative approaches to address this issue. The Region of Waterloo has agreed to accept the sediment. The sediment will be dewatered and transported to the Cambridge landfill site by the City's contractor. Native material beneath the sediment will be excavated and transported to either the Cambridge landfill site andlor to the Waterloo landfill site at the discretion of the Region, depending on where the material is required. Following the transportation of the material to the landfill, the Region will assume responsibility for the material. The sediment will be stored on site, turned over a few times a year, with the sediment analyzed over a 3 year period (2012 to 2014) to determine its viability as a topsoil amendment given its high nutrient value. The Region and the City have agreed to equally partner over the 3 year period for sediment testing at the landfill, sharing resources and test results associated with the work. Depending on the results of the testing, this data will then be utilized to make a case to the Ministry of the Environment to allow for this type of material to be disposed of alternatively and used in the long term in a more sustainable manner rather than filling landfills with a potentially useful and nutrient rich product. IF1-2 1 Staff Re ort p I~t`r~.~-~~,i~iER ~nfrastrurture Servrces Department www.kitthenerta ALIGNMENT WITH CITY OF KITCHENER STRATEGIC PLAN: The partnership that we are proposing to form with the Region of Waterloo is in line with the City's Strategic Plan, particularly the Development and Environment Community Priorities. Community Priority -Environment "Continue to show leadership in the development of an environmentally sustainable community." The approach of testing the sediment once it is at the landfill will provide the Region of Waterloo and the City of Kitchener with data to determine what potential viable disposal alternatives might exist for this type of material. The cost associated with sediment disposal is a problem faced by all municipalities and by choosing the proposed approach; we are demonstrating our leadership in this respect. Community Priority -Development "Maintain a balanced approach to replacing building new infrastructure." There are over eventually require sediment removal and the provide us with a better understanding of the make sediment disposal more cost effective. stormwater management facility cleanouts and infrastructure. and/or expanding existing infrastructure and 100 stormwater management facilities that will work associated with Victoria Park Lake will potential re-use of this material and could help This in turn will result in a greater number of therefore a better maintenance of our existing FINANCIAL IMPLICATIONS: N/A COMMUNITY ENGAGEMENT: During the detailed design of the Victoria Park Lake Improvements, two (2) public information centres (PIC) will be conducted. One PIC was held on June 23rd, 2011, to receive community input early in the design phase. The second PIC will be conducted on September 27t", 2011, to share the outcome of the detailed design and what the public can expect during construction. CONCLUSION: As part of Council's direction to complete the detailed design for the Victoria Park Lake Improvements, a sustainable partnership with the Region of Waterloo to investigate alternative methods of handling stormwater pond sediments, including those from Victoria Park Lake, has been established. ACKNOWLEDGED BY: Pauline Houston, Deputy CAO Infrastructure Services Department IF1 - 3