The City of Coquitlam’s water system had chronic issues with the Burnaby Mountain Pressure Zone (Zone 3) including low pressures in a portion of the zone, operational complexity in its supply, and water quality concerns due to limited water turnover in portions of the supply system. These were being exacerbated by residential densification in the service area. Water Street was retained to develop a solution to these problems. The solution developed was splitting of the existing pressure zone, with the creation of a new pressure zone (Zone 3A) to address low pressures in the eastern portion of Zone 3. Building off the water supply study, Water Street led the detailed design and construction services for a mechanical and electrical rebuild of the Foster Pump Station, as well as construction of a new PRV station (between the two new zones) and new isolation valves and watermain looping at the new zone boundary. which allow for the creation of a new pressure zone to address the low pressure in areas and improve the supply efficiency and redundancy. The project also allowed for the elimination of a small local pump station (the Mara Pump Station), whose service area was absorbed into the new Zone 3A.

The 2025 construction aspect of the project focused on retrofitting and modernizing the 1970s-era Foster Pump Station to serve as the primary supply for the new zone. This approach allowed the City to maximize the use of its gravity supply from Metro Vancouver’s (MV’s) Burnaby Mountain Tank, reducing reliance on energy-intensive, high-head pumping.

The project approach was separated into three key phases:

1. Water Supply Strategy: The initial phase of the project involved GIS methods and hydraulic water modelling to analyze the current water system arrangement and different zone separation options.
   The recommended solution for the proposed Zone 3A supply replaced the existing Foster PS pumps and adds two new jockey pumps to cover the range of daily / seasonal demands. A new PRV station would also allow the Foster Pump Station to provide fire support to the new zone.
2. Preliminary to Detailed Design: Once a zone separation arrangement was determined, concepts were developed to achieve the desired functionality, while maximizing the use of existing infrastructure, and thus reducing resources required and project costs for the City. Water Street managed the design of the upgrades to ensure the station could meet a wide range of operating scenarios, from base day demands to peak summer flows. A critical component of the approach was the development of a complex control narrative that interconnected the Foster and River Heights Pump Stations, as well as the MV supply line, to maintain pressure and fire flows under varying demand conditions. The sizing and location of the new PRV station, along with select looping improvements, were chosen to ensure sufficient fire flows.
3. Construction Sequencing: To facilitate the zone separation within an active system, the construction was strategically divided into three stages.

The project resulted in the successful creation of a new pressure zone to address low pressure areas and improve water supply efficiency and redundancy with spare capacity for service area growth. The retrofitting avoided the construction of a new pump station facility, maximizing the value of existing assets for the City of Coquitlam.