Platt's Drainage Basin Map, 1966

Platt's Drainage Basin Map, 1966

By the 1960s, the Bureau of Reclamation had completed most of the major water development projects in the American West. The Moffat tunnel and Colorado Big-Thompson Project brought water from the western slope of the Rockies to the Front Range, joining the natural snowmelt which supplied the South Platte River. Before reaching the Platte, however, this water funneled into a complex system of ditches and reservoirs to support acres of farmland, and growing metropolises.

This detailed map, drawn by Thomas L. Platt in 1966, shows the entire drainage basin of Boulder County, from the Continental Divide to the Platte River, including creeks, rivers, ditches, and lakes. Thomas Platt was Water Commissioner in Boulder for over 25 years and was a highly respected commentator on water issues.  The Daily Camera quoted him frequently.

Explore the color version of this map, used for the "Our Ditches" page, in high resolution by clicking here

Map courtesy of the Bob Carlson Collection