Recharge offsetting - maintaining recharge in an urban environment

Through the updated Growth Plan for the Greater Golden Horseshoe (2016), the Lake Simcoe Watershed can expect growth of an estimated 9,000 hectares of new development over the next 25 years. The Province of Ontario has increased development density targets which will accordingly increase impervious areas in an already urban environment; making it more difficult to maintain predevelopment recharge rates. Typically, maintaining recharge has focused on the sustainability of natural features such as wetlands and cold water streams; however more recently, it has led to better management of municipal drinking water supplies and stormwater management throughout the Lake Simcoe Watershed. Due to the significant advancement of recharge-based policies within the Lake Simcoe Protection Plan (LSPP) and the South Georgian Bay Lake Simcoe Source Protection Plan, new and innovative development strategies are being implemented within the Lake Simcoe Watershed. Since 2009, the Lake Simcoe Region Conservation Authority has implemented the LSPP recharge policies on behalf of member municipalities to ensure pre-development water balance targets can be achieved through the development plan. The LSPP requires any major development within the Lake Simcoe Watershed to submit a water balance which demonstrates changes to the pre-development water balance will be minimized. Development within a Significant Groundwater Recharge Area also requires a hydrogeological assessment and water balance demonstrating that the quality and quantity of groundwater in these areas and the function of the recharge areas will be protected, improved or restored. More recently, the Approved South Georgian Bay Lake Simcoe Source Protection Plan came into effect July 1, 2015, which requires development proponents to complete water balance and hydrogeological assessments for future development activities proposed under the Planning Act or Condominium Act where applications are within the wellhead protection quantity area. The Source Protection Plan also requires that proponents demonstrate that their projects will maintain the pre-development groundwater recharge rates. The Policy is similar to the Lake Simcoe Protection Plan recharge policies, however it goes one step further and requires recharge offsetting should site conditions not allow for the implementation of on-site Low Impact Development measures to promote recharge. As a result, the Lake Simcoe Region Conservation Authority has developed a recharge offsetting program where all new development or redevelopment greater than 0.50 hectares requires recharge to be maintained after development so that there is no net reduction in water supplied to the groundwater system. Any loss in recharge after implementation of on-site measures will be offset through agreement with the Lake Simcoe Region Conservation Authority under the Conservation Authority's Urban Stormwater Retrofits Projects Program.