July | August 2017

by Jeff Miller
Conflicts over water are as old as civilization itself. The Pacific Institute, a global water think tank based in California, maintains an online water conflict chronology that catalogs disputes going back 5,000 years. So it should be no surprise that in a nation of independent states, many of which share borders that cut across or are defined by water, interstate water conflicts feature prominently in the history of the states.
Since 1785, states have entered into formal agreements, or compacts, about how to share water. A search of CSG’s National Center for Interstate Compacts database results in nearly 40 interstate agreements addressing various water quality and management issues.
But according to Noah Hall, Wayne State University Law School professor and founder of the Great Lakes Environmental Law Center, interstate water conflicts are never really over, even among states with compacts. Hall offers the Colorado River as an example. The 1,450 mile long river is subject to one of the country’s largest interstate compacts. The Colorado River Compact involves seven states, divided into an upper basin—Colorado, New Mexico, Utah and Wyoming—and a lower basin—Arizona, California and Nevada—with additional agreements among the states in each basin.
The original 1922 Colorado River Compact allocated equal amounts of water to the upper and lower basins, based on observed rainfall patterns in the years prior to 1922. But these years were wetter than normal, and the river’s average annual flow is significantly lower than the 1922 estimates—meaning the compact promises more water than is usually available. Significant droughts in the Southwest in recent years have compounded the problem and led to water shortages and conflict between the states.
Although the U.S. Supreme Court has historically shown deference to states with respect to disputes over shared water resources, the court has ruled on a number of cases in which a compact was alleged to have been violated.
Such disputes may be more common in the drier western states, but they are by no means uncommon in other regions. According to Anne Roberts Brody at the Southern Legislative Conference/CSG South, disputes between Alabama, Florida and Georgia over the Alabama-Coosa-Tallapoosa and Apalachicola-Chattahoochee-Flint, or ACF, River Basins stretch back more than 25 years. Alabama and Florida assert that Georgia is overdrawing the rivers, threatening ecological systems and the livelihood of their residents. Alabama filed suit in 1990 to prevent the Army Corps of Engineers from increasing reservoir storage in both basins for the benefit of Atlanta residents. Florida and Georgia later joined the suit against the corps.
In January 1992, the governors of all three states suspended legal action and entered into negotiation, resulting in interstate compacts covering each basin. By 2004, however, both compacts had expired, and legal proceedings resumed. In 2013, Florida filed a motion with the Supreme Court requesting “equitable apportionment” of the waters of the ACF River Basin and a cap on Georgia’s use of the water at 1992 levels. The court accepted the case and assigned a special master to review it.
Interstate groundwater disputes are less common than those involving surface water, particularly when the groundwater is not clearly linked to a surface water source. But in the 2000s, Las Vegas sought to acquire water from the Snake Valley Aquifer, which straddles the Utah-Nevada border. After several years of negotiation, the two states were close to establishing the country’s first interstate groundwater compact. But environmental concerns and resistance from local communities scuttled the deal.
Meanwhile, Mississippi and Tennessee are locked in a battle over the Sparta-Memphis Sand Aquifer, which has served the municipal water needs of Memphis since 1887. In 2005, Mississippi sued the city of Memphis and its water utility, claiming the city’s pumping was depleting the aquifer on the Mississippi side of the border. After two motions were denied and negotiations broke down, Mississippi is suing again with Tennessee now joining the case as a defendant. This time the Supreme Court has accepted what could be a precedent-setting case.
Mississippi’s suit claims that water in the ground beneath the state belongs to the state, even though that water migrates across state lines. This argument runs counter to the Supreme Court’s decades-old precedent of equitable apportionment, which recognizes “equality of right” among states over shared resources. If the court accepts the idea of state ownership of water and rules in favor of Mississippi, warned Hall, states could be held liable for “wrongful conversion” of shared groundwater, leading to potentially significant costs for damages and creating a disincentive for interstate cooperation.
Historically, according to Hall, most interstate water conflicts were about who was able to develop or use water resources. But ecosystem benefits are increasingly seen as a legitimate competing use, and are likely to drive more conflict. The ACF case involving Alabama, Florida and Georgia serves as an example.
Better land use planning and improved water efficiency can help avoid conflict, as can the use of water markets and pricing that reflect the costs of mitigation or prevention of environmental damage due to overuse. But Hall argued that a focus on shared stewardship among state and local leaders is the key. For example, under the Great Lakes Compact, which governs the nation’s largest source of freshwater, state policymakers hold one another accountable, said Hall. This is why some states argue decisions about what may seem like intrastate issues actually affect the entire system. This kind of shared accountability also means less involvement by the federal government—something nearly all state leaders can appreciate.
State of Montana v. State of Wyoming and State of North Dakota
Montana brought suit against Wyoming in 2007, arguing that Wyoming had broken the 1951 Yellowstone River Compact by allowing too much water to be taken from the Tongue River, a tributary of the Yellowstone. In 2016, the Supreme Court found that Wyoming was liable for removing too much water, but only in 2004 and 2006
Kansas v. Nebraska, et al
For many years, Kansas has accused Nebraska of taking more than its share of water from the Republican River Basin through groundwater pumping. In 2015, the U.S. Supreme Court ruled that Nebraska had “knowingly failed” to comply with the 1943 Republican River Compact, awarding Kansas $3.7 million for its losses and $1.8 million in additional penalties.
Texas v. New Mexico and Colorado
In 2013, the Texas Commission on Environmental Quality, on behalf of the state, sued New Mexico, alleging that by allowing farmers in southern New Mexico to pump groundwater connected to the river, the state is unfairly taking water from the Rio Grande that, under the 1938 Rio Grande Compact, should be flowing to Texas. The case is currently before a special master.