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Interstate Stream Commission

Costilla Creek Compact

For additional information, please contact Jonathan Martinez, New Mexico Interstate Stream Commission, in Santa Fe at (505) 827-6160.

Representatives of Colorado and New Mexico signed the Costilla Creek Compact in 1944, and Congress approved it in 1946. The compact was amended through a similar process in 1963. The compact provides for the delivery of apportioned water to users in New Mexico and to Colorado at interstate points of delivery on the New Mexico-Colorado state line. It provides for an administrative commission composed of the official in each state charged with administering public water supplies.

The Costilla Creek irrigation system begins south of the Colorado state border in the Sangre de Cristo Mountains of north-central New Mexico and extends some 40 miles downstream via Costilla Creek and irrigations ditches onto the high desert plains of New Mexico and Colorado. The compact requires daily administration of the direct flow and storage waters of the system during irrigation season. A water master performs this function.