Tad Pfeffer, Nel Caine, and colleagues measured the depth of the Arapaho Glacier west of Boulder at 22 meters (about 72 feet), in a study relevant to water use and environmental change in the Front Range. The measurement helps determine the total volume of ice in the city's watershed and its seasonal waxing and waning. Annual snowmelt may create most of the water the city draws from its watershed, but during drought years such as 2002, it is glacial melt that keeps regional streams flowing late summer. Scientists have determined that the Arapaho and smaller glaciers nearby are shrinking, with the melt particularly noticeable in the last three years. The results from Pfeffer and Caine's research appeared in a Boulder Daily Camera story by Katy Human.