City staff offer new option for deteriorating Riverside Dam: do nothing

As costs to rebuild the Riverside Dam project continue to increase, council is now being given another option by city staff: do nothing.

City of Cambridge staff will give an updated report to council regarding expected costs and the design of the new dam at a council meeting on Dec. 2.

After years of debate on whether the project should go ahead, Cambridge city council voted to rebuild the Riverside Dam in June 2018, with the project scheduled to begin in 2022. In 2019, the dam was originally budgeted at $5.4 million. That has now ballooned to $15.2 million.

Updated increased costs in the report includes additional funding of $375,000.

But an option from the city manager in the latest report is to cancel the work and monitor the condition of the dam at an annual cost of $30,000.

Reads the report:

"AND THAT a passive management approach be initiated for the riverside Dam as outlined in the Report 21-227(CD)Riverside Dam Update, with an increase in future operating budgets of $30,000 for annual inspections and monitoring; AND THAT staff promptly inform Council of any substantive change in the condition or short-term risk associated with the Riverside Dam; AND FURTHER THAT the capital project for Riverside Dam construction, included in the 2022 capital budget, not be approved to proceed and the current capital project A/00024-20 Riverside Dam Detailed Design not continue and the account be closed with the year-end capital forecast report.

The latest cost increase includes $284,000 requested to complete archaeological assessments and $91,000 in the additional design that was not included as part of the original scope of work.

Additional elements in the design and cost include operating gates and valves to reduce flooding potential and help pass sediment, a fish ladder or alternative fish passage method, health, and safety apparatus for safe access, fencing, signs and river barriers.

According to city staff, the detailed design of the new Riverside Dam has progressed over the past year and has reached the 60 per cent design level.

Details of the new dam and how it will be constructed are now available and have been shared with internal and external agencies, Indigenous communities and with the public.  

In 2009, a structural evaluation of the dam was originally completed by Cambridge city staff. It was concluded that the dam was in need of repair.

The city’s evaluation of the alternatives determined that naturalizing the river was the preferred option.

In March 2018, in response to community feedback, city councillors asked staff to prepare another report on how to proceed with repairing or rebuilding the dam.

According to a cultural heritage report, Riverside Dam is over 130 years old and is recognized as a cultural heritage structure.

The project is scheduled to be constructed over 2022 and 2023.