WSP09675

• File Number: 8041
• Description: 208 Clean Water Grant
• State: CO
• Date: 8/16/1982
• Author: CWCB
• Title: Quarterly Reports on the 208 Clean Water Grant for the Water Quality Control Division of the Coloradio Dept of Health
• Water Supply Pro - Doc Type: Publication

l-
I-
l-
I-
l-
I
l-
I
I
I
I
I
I
I
!I
'I
'c

~
II
II
il
I

37SC

SAN JUAN TRIBUTARIES SUBBASIN

The San Juan River Basin drains a 24,945 square mile area
of which approximately 5,740 square miles are in Colorado. The
Colorado portion of the Basin is located in the southwest corner
of the state. It is bordered by the Dolores and Gunnison River
Basins to the north, the Continental Divide to the east and the
state lines to the west and south. Elevat ions range from more
than 14,000 feet above sea level in the San Juan Range to around
6,000 feet at points where the various tributaries exit the
state.

San Juan tributaries which originate in Colorado are the San
Juan mainstem, piedra River, Los pinos River, Animas River, La
Plata River, Mancos River, and McElmo Creek. Water from these
tributaries and a diversion from the Dolores River Basin are used
to irrigate 186,700 acres of agricultural land in Colorado.
Timber, grazing, mining and recreation are also important uses of
land in the San Juan tributaries. Based on the 1980 Census
Report, approximately 47,000 people live in the San Juan
Tributaries area of Colorado.

The tributaries to the San Juan River in Colorado will be
analyzed individually. Although most salt loading studies on the
San Juan Tributaries discuss areas not in Colorado, only
dissolved solid yields and source identification from lands in
Colorado will be presented in this report.

The USGS identifies average annual dissolved solids
discharges for the following San Juan River tributaries at points
near where they exit the state. The average annual dissolved
sol ids discharge for all San Juan tributary lands in Colorado for
1914-57 approximated 476,000 tons.

-34-