Skip to main content

Goal: Deliver Benefits to the Public Study Reveals the Role of Forests in Providing Drinking Water to the Population of Puerto Rico

Map of Puerto Rico showing El Yunque National Forest as a major watershed

Municipalities and populations served by water originating on the El Yunque National Forest in Puerto Rico.

Introduction

Puerto Rico is densely populated, with 3.7 million people living primarily on the mainland island. Forests make up about 54.7 percent of the island’s land cover are important for its water supplies. Researchers determined the amount of water originating on forested land and the total population served by this water.

Summary

Puerto Rico is densely populated, with 3.7 million people living primarily on the mainland island. Forests make up about 54.7 percent of the island’s land cover are important for its water supplies. Eastern Forest Environmental Threat Assessment Center researchers and partners used the Water Supply Stress Index (WaSSI) model, which estimates monthly water balance and flow routing, to quantify the amount of water originating at forested watershed outlets.

To quantify the population that relies on this water, researchers used water intake location data from the U.S. Geological Survey and data on population served from the Puerto Rico Aqueduct and Sewer Authority. They estimated that all lands in mainland Puerto Rico produce 6.5 billion m3/year of water. Of that total, National Forest System lands (3.3% of total land area) provide 219 million m3 of water, and commonwealth and private forest lands (40% of total land area) provide 2.6 billion m3 of water. This water serves a population of 3.6 million people from 113 intakes located downstream of commonwealth and private forest lands.

Thirteen of the intakes that serve 780,000 people are located downstream of El Yunque National Forest, which receives relatively high precipitation and produces the highest runoff on the mainland. This analysis provided quantitative information on water yield from forested lands and sources of water supply in Puerto Rico.

Principal Investigators
Erika Mack, Resource Information Spec.
Ge Sun, Research Hydrologist
RWU
4854 - Eastern Forest Environmental Threat Assessment Center
Strategic Program Area
Water, Air, and Soil
Publication
Quantifying the role of forested lands in providing surface drinking water supply for Puerto Rico
CompassLive Story
Research Partners
U.S. Forest Service Southern Region (Region 8)
Southern Research Station Coweeta Hydrologic Laboratory
External Partners
Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)
Jiangsu Key Laboratory of Agricultural Meteorology, Nanjing University of Information Science & Technology