Limerick Pumping Station
When it was determined that the proposed 28.9-ha Grand River Woods subdivision in Cambridge required a sanitary pumping station, our water / wastewater engineers designed a pumping station that both met the capacity of the subdivision and ensured its long-term sustainability. Not only did our team create a cost-effective solution that minimized construction and operational costs by specifying equipment that best suited the project’s needs, but our design also created an aesthetically pleasing building with a walkout that fit well into the site’s sloping ground.
Initially, our team completed a Schedule B Class Environmental assessment (EA) to identify options and solutions for the sanitary servicing. Through the Class EA process, we evaluated several options and considered the various environmental, social, economic, natural heritage, technical and legal impacts of each option related to the pumping station location, the sanitary outlet, and the sanitary servicing.
This process involved collaboration with multiple stakeholders including the City of Cambridge, Grand River Conservation Authority, First Nations, and the community. Our team facilitated communication between these stakeholders through various meetings and communications, including a Public Information Centre.
Based on the technical review, our team determined that the preferred solution would involving having the sanitary flow travel by gravity to a pumping station located at the low point of the development where it would be pumped via forcemain to a location where it can resume gravity flow in a municipal sanitary outlet. The station has an overflow to a nearby stormwater management pond. Our team completed the detailed design and provided contract administration and inspection services for the Limerick Sanitary Pumping Station and forcemain.
The station we designed is a double-storey building, housing a natural gas standby generator, electrical services, control panel, and a washroom facility. It includes two submersible pumps in a dry well / wet well configuration. The wet well is divided into two cells to allow for easy access to the equipment for operation and maintenance activities. The pumps can be dismantled at the site without disturbing the pump motor. Additionally, it limits the requirements to make regular entries into the wet well for mechanical maintenance purposes.
Odour at the pumping station is mitigated through the use of continuous power ventilation discharging above the roof elevation through a vent stack. Wastewater from the station is discharged through an 805-m long, 200-mm diameter high-density polyethylene (HDPE) forcemain. A design flow of 33L/s was estimated based on the area’s zoning and to service a population of 3,220 people.
The design and construction of the pump station was funded by the developer of the subdivision and then turned over to the City of Cambridge upon completion. This made it necessary for our team to work closely and coordinate with both the developer and the City to not only ensure that the project was delivered on time and on budget, but that the finished product met all of the City’s requirements to allow for a seamless transition.