12/06/2025
Dean Construction completed the 2025 works for the water intake structure at Ontario Power Generation's Darlington New Nuclear Plant in October. Completion of this work on schedule and budget required the 24/7 dedication of Dean's crews
The 2025 works included the dredging of the intake footprint, the drilling of the shaft for the intake riser, as well as the supply and placement of the steel intake liner and its sealing to the bedrock.
Dredging of the hard (blow counts in excess of 100 BPF) glacial till at the intake footprint required the use of a vibrating ripper tooth and the subsequent excavation using rock buckets and a hydraulic clamshell bucket. All of the pre-treatment and excavation was performed with Dean's 190t hydraulic excavator from a spud barge. Approximately 5m of till was removed and the bottom of the excavation was in water depths exceeding 19m.
The shaft for the intake liner was drilled using an array of holes created with a down-the-hole cluster bit. The finished inner diameter of the shaft was 8m and required the removal of approximately 16m of bedrock.
The 6m inner diameter steel intake liner and its cap were fabricated in Hamilton and delivered by barge to the site. It was inserted in the shaft and it's anulus sealed with concrete.
Dean's 2026 works on the site will involve pressure-testing the liner, constructing the base for the intake structure, installing the precast concrete intake modules, removing the liner's cap and placing the final section of the intake.
All of us at Dean would like to thank Aecon and Ontario Power Generation for the opportunity to work on such a unique, legacy project.
