The Big Thompson River flows roughly 75 miles eastward from its headwaters in Rocky Mountain National Park through Estes Park and Loveland to its confluence with the South Platte River. The watershed includes the Big Thompson River, the North Fork of the Big Thompson, the Little Thompson River, Buckhorn Creek, Glacier Creek, and all tributaries prior to joining the South Platte southwest of Greeley. Watershed Maps
Water originating in the Big Thompson River Watershed is shared by more than 800,000 people and used for residential, commercial, agricultural, recreation, and tourism purposes. In addition to its importance as a water supply, a healthy Big Thompson River provides wildlife habitat and aesthetic benefits enjoyed by residents and visitors alike.
Big Thompson Watershed Facts
- includes 173 lakes, 974 total river miles, and 530 perennial river miles, encompassing 7,212 watershed acres and more than 900 square miles
- provides drinking water to roughly 800,000 people in 32 cities, townships, and rural areas on Colorado’s Front Range
- supplies agricultural water averaging 270,000 acre-feet of water each year, or roughly 88 billion gallons of water (one acre-foot equals 325,851 gallons of water, or the average amount two urban families use annually)
- provides habitat for a variety of fish, avian, amphibian, mammal, and flora species
- offers recreational opportunities for millions of people each year, including fishing, tubing, hiking, camping, horseback riding, birding, and touring Rocky Mountain National Park