Interstate Compacts

Who owns water in rivers? Does it belong to the state where the water originated? What about the states downstream? Who decides who gets how much water? These are the basic questions at the heart of Colorado’s river compacts. Colorado is a headwaters state, home to the origins of four major rivers: the Colorado, the Rio Grande, the Platte, and the Arkansas. Although these rivers begin in Colorado, they flow through 18 other states and the Republic of Mexico. People and governments have disputed who should control and use the water in these rivers. Compacts, agreements between the states, seek to peacefully allocate river water.

These compacts determine how much water Coloradans can use. Since groundwater and river water are closely linked, these compacts also affect how much water we can pump from wells. As Coloradans decide who can claim the state’s water – urban, industrial, agricultural, and recreational users, among others – we must comply with the terms of interstate compacts.

What is a compact? A compact is an agreement between two or more states approved by their state legislatures and Congress under the authority of the U.S. Constitution. Compacts are similar to treaties between states. A water compact is a contract between two or more states setting the terms for sharing the water of an interstate stream.

What is the primary purpose of a water compact? The primary purpose is to establish under state and federal law how the water of an interstate stream system will be shared between users in different states.

Click the fluent water facts below to learn about Colorado's interstate compacts.