The Upper Thames River Conservation Authority has taken the next step in removing the dam at the Embro Pond Conservation Area after their project plan for it was approved last week.
Chris Tasker, the UTRCA’s water and information manager, said that the dam, which had been in place since 1959, had become a potential hazard and needed to be decommissioned and removed.
“By doing this we remove a potential hazard posed by the dam, which does not meet current Dam Safety standards,” he said. “Its removal will also limit future maintenance costs and enhance both aquatic and terrestrial environments.”
Tasker went on to say that the dam assessment that the UTRCA had done showed a number of deficiencies, including insufficient spillway capacity, spillway instability, insufficient freeboard, embankment stability and the conveyance of flood flows through the emergency spillway. He added that additional study confirmed concerns over the stability of the embankment.
“When dams require significant upgrades or repairs, it is important to assess whether there are opportunities to reduce the potential hazards associated with failure, reduce ongoing operating costs and enhance aquatic and terrestrial environments by considering dam decommissioning along with considering options for repairs or upgrades,” he said. “There are many similar dams throughout the watershed, many of which may not meet today’s safety standards and which may no longer serve their original purpose.”
The estimated cost to remove the dam at Embro is $140,000, but that cost will likely be refined from its preliminary number after more studies are done. Tasker said once the environmental assessment is completed, the UTRCA will move on to more work associated with the dam’s removal.
“We can work on completing the additional studies and design, seek the required regulatory approvals and pursue funding for the project,” he said. “That schedule will be dependent on securing the funding. Sections 8.4 and 8.5 of the project plan describe the preliminary cost estimates and construction phasing as well as timelines.”
