Little Long Dam Safety Project

The Little Long Dam Safety Project was a significant initiative by Ontario Power Generation (OPG) to rehabilitate and enhance the spill capacity at the Adam Creek Sluiceway to meet new dam safety standards. The project aimed to increase overall discharge capacity of the Little Long headpond by 40%, significantly increasing the electricity generated at this site.

There were three main components to the project:

1. The addition of four new concrete sluiceway bays, providing the additional discharge capacity
2. The replacement of 10 existing sluice gates, gate hoist systems, and superstructures to improve operational safety and reliability
3. The installation of an upstream splash wall to protect against wave and debris overtopping

KGS Group was initially retained by OPG to carry out the concept design for the project, as well as undertake pre-construction geotechnical investigations. The final design and construction phase was executed by OPG under a design-build arrangement with Kiewit as the EPC contractor, where KGS Group’s role transitioned to owner’s engineer. In this role, KGS Group acted as an extension of Ontario Power Generation’s team, contributing to overall project management, contract administration, advisory and technical support. Our responsibilities included review of the contractor and designer’s work for compliance with good practice and the performance specification requirements; Carrying out quality assurance and formal quality audits; and providing resident engineering services to participate in overall coordination, monitoring, commissioning and turnover.

With careful planning, Little Long Dam remained in operation during the project’s four-year lifecycle. Due to the remote site location, the project required setting up a camp to support over 200 workers, complete with all necessary facilities.

Throughout the project, roughly 20 per cent of hours worked were by Indigenous community members, and women contributed around 25 per cent. First Nation subcontracts made up 11 per cent of the overall construction contract cost, covering a range of services from concrete supply to site security. The project was successfully completed with over 2.1 million person-hours worked.