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

Groundwater supplies in the Pawcatuck River watershed are naturally governed by a number of factors, including the local geology, the availability of water supply recharge areas (where infiltration of rainwater occurs), the depth/condition of bedrock and in some cases, river conditions. Based on the project team’s preliminary assessment, the project team has determined that approximately 125 properties warrant further evaluation. Earlier this year, the project team sent a survey to potentially affected property owners; slightly fewer than 50 responses have been received by the Town of Westerly and its consulting engineer to date. Of those that have responded to date, a number of have indicated that their wells have previously experienced lack of water, or draw water from shallow sand formations saturated by river water.

In the coming months, the project team will continue to work with the towns of Westerly and Hopkinton to refine its assessment of private wells, based on the following criteria:

● depths below ground (i.e., deep and bedrock wells will not be affected)

● location with respect to the river (the higher the elevation and the greater the distance from the river, the lower the potential for effects)

● proximity to other tributaries and surface waterbodies and subsoil/bedrock conditions (these other sources reduce reliance on the Pawcatuck River for groundwater supply and more permeable/porous soils and fractured bedrock allow water to move underground to private wells more readily)

● type of well (certain types, like hand-dug wells, are more likely to be affected)

● record of performance (whether they have experienced lack of water during previous dry or drought conditions)

Even if no action is taken, in future years, wells that are affected by changes in river flows will have limited capacity to provide a reliable source of drinking water, as leakage rates through the Potter Hill dam’s failing millrace headgates increase river levels between Potter Hill Dam and Bradford will continue to drop as a result.

Further, scientists predict that as a result of climate change, Rhode Island will experience longer and more frequent periods of drought, that will put more stress on shallow, vulnerable wells, both in terms of water quantity and quality. When the headgates ultimately fail and the river breaches the dam through the millrace channels, these substandard wells will likely experience a sudden failure, with no plan or resources in place to replace the failed well in a timely manner.

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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?