The Idaho Falls Region covers the second largest geographical area of DEQ's regions, with 21.1% of the total area of the state. For such a large region, only 12.9% of the state's total population resides here, resulting in a relatively low density of nine persons per square mile. The low density is attributed to the vast areas of mountains located within the region. Also included in the region are the cities of Idaho Falls, Salmon, Challis, Arco, Rexburg, St. Anthony, and Driggs.

This region is well known for its central Idaho mining and upper Snake River Plain farming. Several active mines are found in this region, and much of the state's sugar beet, wheat, and potato crops are grown here. The area boasts many recreational opportunities as well, from rafting on the Salmon River, fishing at Island Park and the Henry's Fork, to skiing at Targhee near Driggs.

 Air Quality

 Water Quality