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9.6: Water Law

  • Page ID
    11254
  • Federal and state governments have put laws in place to ensure the fair and equitable use of water. Based on the distribution of precipitation in the United States, the states are in a position that requires them to create a fair and legal system for sharing water.

    11.5.1: Water Rights

    Because of the limited supply of water, especially in the western United States, some states have adopted a system of legally dispersing ownership of natural waters. A claim to a portion or all of a water source, such as a spring, stream, well, or lake is known as a water right. Federal law mandates that states control water rights, with the special exception of federally reserved water rights, such as those associated with national parks and Native American tribes, and navigation servitude, which maintains navigable water bodies. Each state in the United States has a different way to disperse and manage water rights.

    A person or entity (company, organization, etc.) must have a water right to legally extract or use surface or groundwater in their state. Water rights in some western states are dictated by the concept of prior appropriation, or “first in time, first in right,” where the person with the oldest water right gets priority water use during times when there is not enough water to fulfill every water right.

    The Law of the River and the Colorado River Compact

    The Colorado River and its tributaries pass through a desert region, including seven states (Wyoming, Colorado, Utah, New Mexico, Arizona, Nevada, California), Native American reservations, and Mexico. As the western United States became populated and while California was becoming a key agricultural producer, the states along the Colorado River realized that the river was important to sustaining population and agriculture in the West.

    The states recognized a water budget was necessary for the Colorado River Basin to guarantee each state's certain perceived water rights. Thus was enacted the Colorado River Compact in 1922 to ensure that each state got a fair share of the river water. The Compact granted each state a specific volume of water based on the total measured flow at the time. However, in 1922, the flow of the river was higher than its long-term average flow, consequently, more water was allocated to each state than is typically available in the river.

    Over the next several decades, many other agreements and modifications would follow the Colorado River Compact, including agreements that brought about the Hoover (formerly Boulder) and Glen Canyon Dams, and a treaty between the American and Mexican governments. Combined, the agreements became known as “The Law of the River.” Despite adjustments to the Compact, many believe that over-allocation is still prevalent, as the Colorado River no longer reaches the Pacific Ocean, its original terminus (base level). Dams causing diversion and evaporation of Colorado River water have resulted in serious water budget concerns in the Colorado River basin. Predicted drought associated with global warming causes additional concerns about future over-allocation of Colorado River flow.

    The Law of the River highlights the complex and prolonged nature of interstate water rights agreements, as well as the importance of water.

    Snake Valley

    In 1989, the Southern Nevada Water Authority (SNWA) submitted applications for water rights to pipe up to 155,000 acre-feet of water per year (an acre-foot of water is one acre covered with water one foot deep) from Spring, Snake, Delamar, Dry Lake, and Cave valleys to southern Nevada (mostly Las Vegas) [17]. Unlike the other valleys, Snake Valley straddles the border of Utah and Nevada, where more of the irrigable land area is on the Utah side of the border. Nevada and Utah attempted a comprehensive agreement, but negotiations have yet to be settled.


    NPR story on Snake Valley

    SNWA History

    Dean Baker Story

    11.5.2: Quality Protection

    Two major federal laws that protect water quality in the United States are the Clean Water Act and the Safe Drinking Water Act. The Clean Water Act, an amendment of the Federal Water Pollution Control Act, protects navigable waters from dumpage and point-source pollution. The Safe Drinking Water Act ensures that water that is provided by public water suppliers, like cities and towns, is safe to drink [18].

    The Superfund program ensures the cleanup of hazardous contamination and can be applied to situations of surface water and groundwater contamination. It is part of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980. It allows state governments and/or the U.S. Environmental Protection Agency power to remediate polluted sites through either actions or funds provided by the polluter that caused the contamination.