Instead of building berms we could just dredge the river and make it deeper. That’s the talk about town. Let’s consult my trusty rumour stick.
Both berms and dredging are tools used to mitigate flooding. You either dig down or build up. Why are berms the right tool for Drumheller? Let’s compare. To meet the same and necessary added capacity for the river, we would need to either excavate 300 m3 per metre of length from the river bed or build up berms on either side of the river a total of 90 m3 of fill per metre of river. The dredging would be needed along the full 38 km length of the river while the berms need only be built between where the houses and the river meet.
Dredging would be a huge and costly undertaking with a significant impact on the fish and aquatic life in the river and the success of the project would be impacted greatly by the silty river bed.
Decisions made to protect the community are made based on both the positive and negative impacts. How effective will the solution be? How much will it cost? What is the impact on the environment. Using that filter, the Town is confident it is making the best decisions to protect Drumheller.