Lake Patillas Water Level
Lago Patillas · Patillas, Puerto Rico · operated by Puerto Rico Electric Power Authority (PREPA/AEE)
Water level
65.58 m
above mean sea level · 2026-09-22
SafetyAt 65.58 m, Lake Patillas is close to its seasonal norm for September, sitting above 34.3% of September days recorded since 1995.
Recorded range
61.59 – 68.21 m
Position in range
60.3%
Seasonal percentile
34.3%
Record since
1995
Official operating levels (PREPA)
Overflow
67.87 m
Safety
62.18 m
Observation
58.82 m
Adjustments
57.00 m
Control
53.34 m
Out of service
51.52 m
These are the thresholds the Puerto Rico Electric Power Authority publishes for this reservoir. They, not a storage percentage, are what trigger operational adjustments and rationing decisions on the island.
The chart plots where the water level sits inside the range this reservoir has recorded since 1995 (61.59 m to 68.21 m). It is a level position, not a share of storage capacity — Puerto Rico does not publish reservoir volume.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Dam and gauge
Design capacity
17.64 hm³
National Inventory of Dams
USGS gauge
50093045
Daily values, 15-minute source data
Municipality
Patillas
South Puerto Rico
Primary use
hydropower
PREPA / AEE
Design capacity is the volume the dam was built to impound, from the US Army Corps of Engineers' National Inventory of Dams. It describes the size of the reservoir — it is not used to compute a fill percentage, because the elevation-to-volume curve needed for that is not published for Puerto Rico.