PUERTO RICO FLOW REPORT
Last Updated: December 4, 2025
Puerto Rico's river systems have recently experienced varying streamflow conditions, with some rivers showing signs of decreased flow and others indicating potential flooding risks. For water enthusiasts looking into seasonal trends and river health, it's important to note that the Rio Grande de Arecibo near Utuado, a popular whitewater destination, is currently flowing at 198 cubic feet per second (cfs) with a gage height of 4.98 feet, which is slightly below normal levels. Conversely, the Rio Culebrinas at the Margarita Damsite near Aguada has seen a substantial increase in streamflow to 1640 cfs, significantly above the norm (188.62% of average), and a gage height of 11.06 feet, indicating possible flooding conditions that may affect nearby areas.
Within this diverse hydrological landscape, the Rio Grande de Manati at Ciales and the Rio Grande de Arecibo near San Pedro have experienced notable reductions in flow, with the former down to 104 cfs, a sharp 46.82% decrease from normal. The Rio Guanajibo near Hormigueros and the Rio Grande de Anasco near San Sebastian have also seen decreases in flow, which could signal emerging flow droughts, impacting local ecosystems and water availability. On the other end of the spectrum, the Rio Culebrinas at Hwy 404 near Moca has shown an alarming 86.88% increase in streamflow in the last 24 hours, up to 299 cfs, which could challenge even seasoned whitewater enthusiasts and may affect downstream conditions. These fluctuations underscore the dynamic nature of Puerto Rico's rivers and emphasize the need for residents and visitors to stay informed about current water conditions for safety and recreational planning.
Puerto Rico has a tropical climate with high precipitation rates, intense storms, and frequent floods. The island has several major surface flows, including the Rio Grande de Loiza, Rio de La Plata, and Rio de La Seda. There are several dams and reservoirs to control water flow, with Carraizo and La Plata being the largest. The island's hydrology is influenced by the topography, bedrock, soil, and vegetation. The watershed management plan is based on the need to reduce flooding and erosion, improve water quality, and conserve natural resources. The snowpack has no correlation with hydrology in Puerto Rico due to its tropical location. The island is prone to flash floods and landslides, which are worsened by deforestation, urbanization, and climate change.