Stillwater Reservoir

WOONASQUATUCKET RIVER· Providence, Rhode Island· Built 1918· Concrete· 20 ft tall
High Hazard Fish And Wildlife Pond Recreation State Government

Key Takeaway

Stillwater Reservoir is classified as high hazard in Rhode Island. It was completed in 1918 and is 108 years old. Its primary use is fish and wildlife pond. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 20 ft (taller than 82% in RI)
Dam Length670 ft
Dam TypeConcrete
Max Storage3.9K acre-ft
Normal Storage2.4K acre-ft
Surface Area240 acres
Drainage Area26 sq mi
Max Discharge1,800 cfs
Year Completed1918 (108 years old)
NID IDRI03101

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: Yes
Last Inspection: August 15, 2014
State Regulated: Yes
Regulatory Agency: DS

Ownership

RI DEM FISH & WILDLIFE

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Stillwater Reservoir?

Stillwater Reservoir is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Stillwater Reservoir?

Stillwater Reservoir is owned by RI DEM FISH & WILDLIFE (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Stillwater Reservoir built?

Stillwater Reservoir was completed in 1918, making it 108 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of Stillwater Reservoir?

Stillwater Reservoir serves the following purposes: Fish And Wildlife Pond, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Stillwater Reservoir?

Stillwater Reservoir has a dam height of 20 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.

When was Stillwater Reservoir last inspected?

Stillwater Reservoir was last inspected on August 15, 2014. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.