ASCO successfully tendered this $22,800,000 project for the Leslie St SPS located in Markham, Ontario, in late 2012. The project was to increase the Station’s capacity 3,800 L/s to 7,500 L/s of a critical pumping station on the York-Durham sewage distribution network. The work included process, electrical, mechanical, energy systems and building upgrades to achieve LEED certification.

Key Features of the project are:

• Overall capacity of the station was increased by installing two new Dry Pit Centrifugal Sewage Pumps c/w 5 Kv Motors and Adjustable Speed Drives. The four existing pumps were refurbished and provided with new Medium Voltage Solid State Soft Starters.

• Construction work included upgrading the electrical medium voltage system c/w new back-up power, and SCADA infrastructure replacement to accommodate present and future upgrades. The existing switchgear line-up was replaced with a new three-section 4160 V Permanent Switchgear, complete with new SCADA infrastructure for new equipment.

• The existing back-up power system was replaced with three 2000 kW permanent generators, with a 38,250 L underground diesel fuel tank.

• The Administrative Building was entirely upgraded and is one of the first pumping stations in in Ontario to receive LEED certification.

Construction Challenges and Achievements:

The Leslie Sewage Pumping Station presented unique challenges such as ensuring uninterrupted power supply for the pumping and electrical equipment to maintain the station's continuous operation. To aid in this effort, temporary generators and switchgear were utilized to provide power to the new pumps until they could be switched over to the permanent systems. As a result, it was critical that the project be staged in several phases with the pumping, electrical, standby power and SCADA having been coordinated and integrated to maintain continuous operation; this required an extensive degree of coordination with all the stakeholders.