When a river runs through more than one state, management of the available surface freshwater resources would be nearly impossible if not for interstate water compacts.
River compact commissions oversee interstate water allocation.
Photo of railroad bridge over Red River courtesy of Stan A. Williams/TxDOT
Compacts, which are agreements signed by representatives of the states involved and ratified by the legislature of each state and by Congress, establish how the states along a particular river will equitably allocate their water. Each compact is administered by a commission composed of representatives from each state and, in some cases, a representative of the federal government, appointed by the president.
Texas Compact Commissions
Texas is a member of five interstate river compacts, covering the Rio Grande, Pecos, Canadian, Sabine, and Red rivers.
The compact commissioners representing Texas—all of whom are appointed by the governor, with the exception of the TCEQ’s executive director, who is by statute one of the commissioners for the Red River Compact—protect the state’s rights under the compacts, oversee water deliveries from one state to another, and work to prevent and resolve any disputes over water. The compact commissions are authorized to prepare and maintain comprehensive plans for the operations of the rivers, monitor activities affecting water quantity and quality, and engage in water accounting and rulemaking. The Texas attorney general provides legal support and the TCEQ provides administrative and technical support.
“The TCEQ maintains a database of historical documents and records, river flows, water deliveries, and other technical information needed to administer the compacts,” says Herman Settemeyer, coordinator of the agency’s Interstate River Compact Program. Settemeyer, who has been with the TCEQ or its predecessor agencies since 1975, holds a B.S. in agricultural engineering from Texas A&M and an M.S. from the University of Wyoming.
Some of the compacts require a formal water accounting. “We develop and review these formal water accountings and provide hydrological analysis to the compact commissioners on how the water is delivered,” he adds. “If there are upstream changes to the timing or amount of water released along the river, we need to understand how that is going to affect water deliveries to Texas.”
The Rio Grande begins in the mountains of southern Colorado, flows southward through New Mexico, and then forms the boundary between Texas and Mexico as it flows to the Gulf of Mexico.
The Rio Grande Compact is the oldest of the Texas interstate compacts. Signed in 1938 by Texas, Colorado, and New Mexico, and approved by Congress in 1939, the compact apportions the waters of the Rio Grande and its tributaries above Fort Quitman, Texas, among the three states.
River compacts establish how the states along a particular river will equitably allocate their water. For the Rio Grande, New Mexico delivers its water obligation into the Elephant Butte Reservoir, located near Truth or Consequences, New Mexico, about 100 miles upstream of El Paso and the Texas state line.
TCEQ photo by Herman Settemeyer
The compact allocates water on an “inflow/outflow” basis. This means that Colorado must deliver to the New Mexico state line an amount of water that varies with the flows recorded at various stream gauges in the Rio Grande Basin in Colorado. Similarly, the amount of water that New Mexico is required to deliver to Texas depends upon gauged flows in the Rio Grande in north-central New Mexico. Instead of delivering the water to the state line, however, New Mexico delivers its water obligation into the Elephant Butte Reservoir, located near Truth or Consequences, New Mexico, about 100 miles upstream of El Paso and the Texas state line.
Throughout the years, Texas, New Mexico, and Colorado have had various disputes over the Rio Grande Compact. One example concerns the Elephant Butte Reservoir.
“The water in the reservoir supplies an irrigation district in New Mexico and another in Texas,” says Settemeyer. “For over 20 years, the two states, the two districts, and the Bureau of Reclamation had been trying to work out an operating agreement to make sure both districts are treated equally. Recently, the Texas commissioner helped the parties reach a consensus, and a formal agreement was signed by the districts and [the Bureau of] Reclamation. The districts have been working well together under the new agreement and litigation was avoided.”
The Pecos River rises in north-central New Mexico and flows southward, where it joins the Rio Grande in the backwaters of the Amistad Reservoir. With approximately 350 of its total of 900 miles located in Texas, the Pecos serves as the eastern boundary of the most mountainous and arid region of Texas. It was once a major river, fordable at only a few places by settlers and cattle drivers heading west. But the quantity and quality of the Pecos River water reaching Texas have been reduced over time, due to water diversions, the construction of dams, groundwater pumping, the introduction of the non-native salt cedar tree, and salinity in the river.
Salinity is especially high at the portion of the river known as Malaga Bend, located near Malaga, New Mexico, just upstream of the state line.
“A series of springs at Malaga Bend can put anywhere from 400 to 600 tons of salt a day into the Pecos River,” says Texas Pecos River Commissioner J.W. Thrasher Jr. “We’re working with a company that would like to pump the water into pits and evaporate it for salt. Taking out as much salt as we can from the river would improve the water quality in the Pecos.”
The Pecos River Compact, signed by Texas and New Mexico in 1948, and approved by Congress the following year, requires New Mexico to maintain deliveries of water to Texas based on 1948 water-use conditions in New Mexico.
For years, Texas considered New Mexico to be deficient in fulfilling the terms of the contract, so the state filed suit in the U.S. Supreme Court in 1974. In 1987, the Supreme Court ruled that New Mexico had violated the Pecos River Compact by depriving Texas of 340,100 acre-feet of water for the period 1950 to 1983. An acre-foot of water—the amount it would take to cover one acre of land with one foot of water—is about 326,000 gallons. Since completion of the litigation, New Mexico has taken measures to comply with the compact.
“New Mexico has spent a lot of money to make the state-line deliveries,” says Thrasher. “In the past, there was a lot of animosity between the two states over the Pecos River Compact. Now we have a good working relationship.”
From its source in the Cimarron Mountains of New Mexico and Colorado, the Canadian River flows in an easterly direction through the Texas Panhandle above Amarillo, then into Oklahoma where it joins the Arkansas River a few miles below Muskogee. With sufficient rain, it can carry large amounts of water, but it is more typically a low-volume, slow-flowing river. The river is an important municipal water source for the Texas Panhandle and central Oklahoma.
Signed by representatives of Texas, New Mexico, and Oklahoma in 1950, the Canadian River Compact was ratified at the federal level in 1952. The compact apportions the waters of the river basin equitably among the three signatory states through storage limitations. Texas and Oklahoma filed litigation in the U.S. Supreme Court against New Mexico over its storage of water. The litigation resulted in increased waters released to Texas from reservoirs in New Mexico.
The impetus for the Sabine River Compact arose from competing claims to the river by local water users in both states, who finally agreed that they needed a compact to apportion the waters.
Sabine River photo courtesy of the Sabine River Authority
The Sabine River begins east of Dallas and flows southeasterly through the prairie country of northeast Texas, through pine forests along the Texas-Louisiana border, and then south through bayou country to Sabine Lake and the Gulf of Mexico. The river supplies water for municipal, industrial, irrigation, recreation, mining, hydroelectric, and domestic and livestock purposes.
The Sabine River Compact was approved by the Texas Legislature in 1953, and was signed by the Louisiana Legislature and ratified by Congress in 1954. The impetus for the compact arose from competing claims to the river by local water users in both states, who finally agreed that they needed a compact to apportion the waters.
The compact commissioners oversee water quantity and water quality measurements within the Sabine River Basin to ensure compact compliance and approval of withdrawals of water. Unlike most Texas rivers, the Sabine is entirely in an area of abundant rainfall, and because of this, the compact has functioned with little controversy.
The Red River—the sixth longest river in the United States—flows across the Texas Panhandle, down the Texas-Oklahoma border, through southwestern Arkansas, and into Louisiana, where it empties into the Mississippi and Atchafalaya rivers.
Prompted by the drought of the 1950s, the Red River Compact was completed in 1978 after more than 20 years of formal negotiations. The compact, which went into effect in 1980, apportions the waters of the Red River and its tributaries by dividing the river into five east-to-west “reaches,” and then into sub-basins.
The compact also gives its commission limited authority over water pollution in the basin. The states and the federal government are working to alleviate natural salt pollution, which is a significant limitation to water use in the basin.
In the last 10 to 15 years, the Endangered Species Act has played an increasing role in the responsibilities of interstate river compacts. Listed endangered species affecting the compacts include the Arkansas River shiner on the Canadian River, the Pecos blunt-nose shiner on the Pecos, and the Rio Grande silvery minnow and the southwestern willow flycatcher on the Rio Grande.
“We work with other states to ensure that water deliveries are maintained while protecting the various endangered species,” Settemeyer says. “For example, we take into consideration what happens to the silvery minnow downstream when water is released or diverted upstream.”
Settemeyer feels that states working together to ensure compliance with the compacts and meeting their water deliveries is the biggest success story for the interstate compact commissions. “Our job,” says Settemeyer, “is to get the water to Texas.”
For more information, visit the Interstate River Compact Commissions.
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