S-161
S-161 is a concrete dam located in Hillsborough, Florida, built in 1975. It carries a High hazard potential classification and has a satisfactory condition assessment.
About S-161
The primary purpose of S-161 is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Swfwmd (local government). It impounds the Palm River near Tampa.
The dam stands 64 feet tall and stretches 200 feet across, creates a reservoir covering 173 acres, has a maximum storage capacity of 11,000 acre-feet, and collects water from a drainage area of 192 square miles. Completed in 1975, the structure is well into its service life at over 50 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 11/13/2024.
At 64 feet, this dam is taller than 96% of all dams in the United States.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Florida dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Florida |
| County | Hillsborough |
| Nearest City | Tampa |
| River/Stream | Palm River |
| Coordinates | 28.01739, -82.37136 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 64 ft |
| Dam Height | 20 ft |
| Dam Length | 200 ft |
| Year Completed | 1975 (51 years old) |
Storage & Hydraulics
| NID Storage | 11,000 acre-ft |
| Max Storage | 11,000 acre-ft |
| Normal Storage | 6,140 acre-ft |
| Surface Area | 173 acres |
| Drainage Area | 192 sq mi |
| Max Discharge | 4,000 cfs |
Ownership & Safety
| Purpose | Water Supply |
| Owner | SWFWMD |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 11/13/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | FL00640 |
| Federal ID | FL00640 |
| More Info | State Dam Safety Program |