S-161

Palm River· Hillsborough, Florida· Built 1975· Concrete· 20 ft tall
High Hazard Water Supply Flood Risk Reduction State Government

Key Takeaway

S-161 is classified as high hazard in Florida. It was completed in 1975 and is 51 years old. Its primary use is water supply. 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 48.9% in FL)
Dam Length200 ft
Dam TypeConcrete
Max Storage11.0K acre-ft
Normal Storage6.1K acre-ft
Surface Area173 acres
Drainage Area192 sq mi
Max Discharge4,000 cfs
Year Completed1975 (51 years old)
NID IDFL00640

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: May 19, 2023
State Regulated: Yes
Regulatory Agency: FDEP

Ownership

SWFWMD

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of S-161?

S-161 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 S-161?

S-161 is owned by SWFWMD (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was S-161 built?

S-161 was completed in 1975, making it 51 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 S-161?

S-161 serves the following purposes: Water Supply, Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is S-161?

S-161 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 S-161 last inspected?

S-161 was last inspected on May 19, 2023. 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.