Frost line depth in Modoc County, CA

How deep the ground freezes in Modoc County, CA

20 in. Dig to 20 in, just below the frost. Nearest NOAA station: Alturas Muni Ap, 10.6 mi.

Your building department sets the legal frost line depth (IRC Table R301.2(1)); footings must go below it (R403.1.4.1). Call them before you dig.

Code depth · Snow