What safety hazards are associated with the mill and dam structures?

Remnant mills and low-head dams in general pose serious risk to people who recreate near them. Potter Hill Mill is a set of building structures first constructed in the mid-1800s, and currently they are in serious disrepair. Trespassers on the mill site may access these dangerous structures, and serious injury may result. Additionally, the mill buildings are collapsing into the river, representing a significant safety hazard to recreational boaters passing downriver and other water recreation users.

The Potter Hill Dam has a dangerous hydraulic pattern at the base of the structure during high flows (known as “keepers” or “roller waves'') where recirculating currents occur. For the Potter Hill Dam site, this dangerous hydraulic pattern exists even with lower flows, and presents an increased risk due to the dam’s narrow spillway width. The hydraulic effects and currents are very difficult to get out of and account for multiple injuries and drownings nationally each year.

The videos below provides detailed explanations of the risks of low head dams.

https://www.youtube.com/watch?v=GVDpqphHhAE 

https://www.youtube.com/watch?v=AcrInFgD8gA 

Show All Answers

1. Why is the dam being removed?
2. Could the dam be repaired or partially removed?
3. Could a design similar to that of the Bradford fish passage project be used for the Potter Hill project?
4. What alternative designs have been considered and why was the proposed design selected?
5. What safety hazards are associated with the mill and dam structures?
6. How will removing the dam affect water levels in the river?
7. Will my household well be affected?
8. Many properties along the Pawcatuck River have private drinking water wells, especially on the Hopkinton side of the river. How many homeowners’ wells could be affected by the predicted drop
9. Will Westerly’s municipal water wells adjacent to the Pawcatuck River be affected?
10. How will removing the dam reduce flood risk to upstream and downstream properties? Will larger flood events (i.e., the 500-year recurrence flood) be worse upstream or downstream following dam removal?
11. Will removal of the dam cause increased flooding to downstream areas, including downtown Westerly?
12. How will removing the defunct dam and mill affect public access to and uses of the river?
13. How will removing the dam affect fish and wildlife?
14. How will removing the dam affect wetland systems upstream of the dam?
15. Is the proposed design accounting for climate change projections and worst-case future hydrologic scenarios?
16. Who is the project team?
17. What are the next steps?
18. Where can I get more information on the project?