Patillas Dam
Patillas Dam is a concrete dam located in Patillas County, Puerto Rico, built in 1976. It carries a High hazard potential classification and has a poor condition assessment.
About Patillas Dam
The primary purpose of Patillas Dam is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Commonwealth Of Puerto Rico (local government). It impounds the Grande De Patillas River near Patillas.
The dam stands 127 feet tall and stretches 1,067 feet across, creates a reservoir covering 367 acres, has a maximum storage capacity of 17,073 acre-feet, and collects water from a drainage area of 25 square miles. Completed in 1976, the structure is 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 poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. An emergency action plan is in place for this dam. The most recent inspection on record was 03/05/2020.
At 127 feet, this dam is taller than 98% 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 Puerto Rico 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 | Puerto Rico |
| County | Patillas |
| Nearest City | Patillas |
| River/Stream | Grande De Patillas River |
| Coordinates | 18.01906, -66.02166 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 127 ft |
| Dam Height | 127 ft |
| Dam Length | 1,067 ft |
| Year Completed | 1976 (50 years old) |
Storage & Hydraulics
| NID Storage | 17,073 acre-ft |
| Max Storage | 17,073 acre-ft |
| Normal Storage | 14,305 acre-ft |
| Surface Area | 367 acres |
| Drainage Area | 25 sq mi |
| Max Discharge | 79,000 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | COMMONWEALTH OF PUERTO RICO |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Poor |
| Last Inspection | 03/05/2020 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | PR00023 |
| Federal ID | PR00023 |
| More Info | State Dam Safety Program |