The water flowing through Yellowstone and the Greater Yellowstone Ecosystem (GYE) is a vital national resource. The headwaters of seven great rivers located here flow from the Continental Divide across the nation to the Pacific Ocean, and the gulfs of California and Mexico. Rain and snow in the mountains and plateaus of the Northern Rockies flow through stream and river networks to provide essential moisture to much of the American West. Together, Yellowstone’s streams and rivers support an abun