Utah’s rapidly growing population coupled with its pronounced diverse topography makes it more vulnerable to the effects of a potential decrease in snowpack and consequentially, water resources. Existing research suggests that the snowpack in the state of Utah is declining. Nearly 70 percent of mountain precipitation arrives as snow during October thru March and peaks near April 1. This snowpack is a critical form of water storage for the state. As it melts gradually over the summer, it becomes an important source of runoff. Understanding the climate controls on past snowpack will help water managers to plan for the future needs and demands of this resource. Forest Service scientists and their partners developed an April 1 snow water equivalent (SWE) reconstruction over a 139-year period, from 1850–1989, using increment [tree] cores combined with available tree-ring chronologies in the region.. In the state of Utah, the SWE was reconstructed for 38 snow course locations. These individual reconstructions were then interpolated to a 4-kilometer (about 2.5 miles) grid, with elevation correction, to create an SWE product that can be used for water management. Their research results showed a significant correlation with observed SWE as well as good correspondence to regional tree-ring-based drought reconstructions. The SWE reconstruction represents a useful proxy of past mountain snowpack at the watershed level.