PUERTO RICO FLOW REPORT

Last Updated: December 19, 2025

Puerto Rico's river systems have shown varying streamflow rates across the region, presenting a diverse picture for water enthusiasts and environmental analysts. Notably, the Rio Culebrinas near the Margarita Damsite in Aguada has experienced a significant uptick in flow, with the latest measurement indicating a streamflow of 1640 cubic feet per second (cfs), a sharp 47.75 cfs increase in the past 24 hours, which is 188.62% of the river's normal flow for this time of year. This could be of interest for whitewater activities if safety conditions allow, but it also raises a potential concern for flooding in nearby areas. Meanwhile, the Rio Grande De Loiza at Caguas has seen a considerable decrease in streamflow, down by 47.12 cfs in the last day, now flowing at an abnormally low rate of 110 cfs, which is 40.46% below the expected norm, indicating a potential flow drought that could affect water availability in the region.

In contrast, the Rio Guanajibo near Hormigueros remains close to its average flow at 198 cfs, just 12.02% below normal, despite a decrease of 1.98 cfs over the last 24 hours. This suggests stable conditions for the river, which is important for the ecosystem and local communities relying on these waters. The Rio Grande De Arecibo below Utuado, which traverses a significant watershed, is currently at 143 cfs, marked by a slight decline and running at 27.79% of its typical flow, which may impact seasonal trends in the area. The Rio Grande De Anasco near San Sebastian and the Rio Culebrinas at Highway 404 near Moca also report diminished streamflows at 290 cfs and 106 cfs respectively, hinting at lower-than-average water levels that could affect the surrounding habitats and any recreational usage of these rivers. These varying streamflows across Puerto Rico's rivers highlight the need for ongoing monitoring to manage water resources effectively and to prepare for the impacts on the environment and human activity.