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An Introduction to Water Law

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Colorado River Aqueduct, From Colorado River to Lake Mathews, Parker Dam, San Bernardino County, CA. ("Intake stream on ground looking west as it flows downstream to Lake Mathews, all water coming from pumps.") (Jet Lowe, 1998.) Library of Congress Prints and Photographs Division, http://hdl.loc.gov/loc.pnp/hhh.ca2472/photos.382971p.
Colorado River Aqueduct, From Colorado River to Lake Mathews, Parker Dam, San Bernardino County, CA. (“Intake stream on ground looking west as it flows downstream to Lake Mathews, all water coming from pumps.”) (Jet Lowe, 1998.) Library of Congress Prints and Photographs Division, http://hdl.loc.gov/loc.pnp/hhh.ca2472/photos.382971p.

Although I grew up in an arid western state, my first real awareness of the complicated rules governing water usage came when I saw the movie The Milagro Beanfield War in 1988.  The action in the movie centers around the accidental and illegal diversion of water by Joe Mondragon, which brings down the wrath of the state government and local land developers.

While we might think of water resources as being of particular importance in the arid West, the sharing of water resources is an important issue throughout the country and affects farmers and ranchers; interstate transportation; and recreational uses by fishermen, boaters, and other outdoor enthusiasts.  When it comes to looking at how water resources are regulated, there are state water laws as well as federal ones, issues relating to water on private land versus public, and interstate water compacts.

Water law in the United States developed in different directions based in large part on geographical conditions as well as land ownership.  Water rights in most of the eastern and midwestern United States fall under riparian law.  “Riparian” refers to the land by a stream or a river and “riparian rights” refer to the rights of a landowner who holds this land to use the water on their land.  The standard for use has been “reasonable use,” though under modern state laws those with riparian rights must usually apply to the relevant state agency for a permit to use the water.

In nine of the western states, the prior appropriation doctrine has been the standard for water use.  This use developed initially in the public lands of the west among the early miners who needed access to water.  They did not own the land they worked so they could not claim riparian rights to a water source.  The rule developed that the first one to put the water to use had the priority right to the water – they appropriated it.  Court decisions and state law have validated this system and appropriated rights belong to anyone who puts the water to “beneficial use.”  The remaining states, ten western and midwestern states, operate under a mix of riparian and prior appropriation water laws.

The federal government is involved in water rights as well.  Under the reserved rights doctrine, public lands and Indian reservations set aside by the government are understood as having the right to sufficient water.  The origin of this doctrine was hammered out in a 1908 United States Supreme Court case, Winters v. United States, 207 U.S. 564.  The case involved the use of the Milk River by the Indians of the Fort Belknap Reservation in Montana and local settlers who were on land which the Indians had ceded to the United States in 1888.  The case held that there was an “implied reservation … of a sufficient amount of water from the Milk River for irrigation purposes” which was not affected either by the Indians’ cession of land in 1888 or the admission of Montana to the Union.

The case further established that “The government of the United States has the power to reserve waters of a river flowing through a territory and exempt them from appropriation under the laws of the state which that territory afterwards becomes, 148 F. 684 affirmed.”  This doctrine has been applied in other situations when Congress has set aside federal land for a use – e.g., forest, wildlife refuge, or military base – which requires water for that use.  This doctrine was affirmed in the 1963 decision Arizona v. California, 373 U.S. 546 – a long-running water rights case involving the Colorado River.  In this case, the United States intervened to protect federal water rights including the rights for five Indian reservations.  The case began in 1952 as an original jurisdiction case for the U.S. Supreme Court which appointed a special master who oversaw the proceedings and made recommendations to the Court.  The Court’s 1963 decision adopted many of these recommendations but there have been subsequent issues with additional court rulings in 1983 and 2000.

These are just a handful of the issues involved with water law.  I have not yet touched on groundwater, navigation, interstate water compacts, environmental regulations, and a dozen other water law issues.  However, there are a number of useful books on water law.  You can find these and other books in the Library of Congress online catalog by searching on the subject term “Water — Law and legislation — United States.”  Here are just a few examples:

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