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Sandra Postel directs the independent Global Water Policy Project and lectures, writes, and consults on international water issues. She is also Freshwater Fellow of the National Geographic Society, and serves as lead water expert for the Society's freshwater initiative. Sandra is the author of several acclaimed books, including the award-winning Last Oasis, the basis for a PBS documentary. Her essay "Troubled Waters" was selected for Best American Science and Nature Writing. Sandra is a Pew Scholar in Conservation and the Environment, and has been named one of the "Scientific American 50" for her contributions to water policy.

Drought Hastens Groundwater Depletion in the Texas Panhandle

Persistent drought in northwest Texas is leading farmers to pump more water from the Ogallala Aquifer, hastening the depletion of this crucial water supply. Over the last decade, from 2004-2014, average underground water levels across the 16-county High Plains Underground Water Conservation District (HPWD) have dropped 8.83 feet (2.69 meters), with three counties seeing average…

West-Slope Colorado Towns Restore Local Flows, Even as Thirsty Front-Range Lawns Drink From their Rivers

  By Sandra Postel and Todd Reeve When residents in Denver, Colorado Springs and other cities on the Front Range of the Rocky Mountains turn on their sprinklers to irrigate lawns, they rarely think about the fate of fish in the headwaters of the Colorado River on the other side of the Continental Divide. But,…

Along the Rio Grande, An Innovative Water Market Restores Riverside Habitat

With rivers in the American Southwest dammed, diverted, drought-stricken and running dry, their fate is increasingly in human hands. Now, in the southern portion of the Rio Grande in New Mexico, a unique partnership of irrigators, government agencies and conservationists is returning some water to the river’s floodplain – and to the native trees, songbirds,…

Recent Loss of Freshwater Wetlands Worldwide Valued at $2.7 Trillion per Year

The question of whether to drain a wetland to make way for a shopping mall or a cornfield, or to instead leave the wetland intact, often seems like a no-brainer: the “development” options have a clear dollar value, but the wetlands themselves do not. But therein lies a big problem. Wetlands do vital work.  They…

World’s Large Cities Move Water Equivalent to Ten Colorado Rivers to Meet their Annual Water Needs

As cities grow in population and economic activity, they reach further and further out to find water to meet their needs. Now, a new study has estimated that collectively the world’s large cities, defined as those with at least 750,000 people, move 504 billion liters (133 billion gallons) of water a day a cumulative distance…

The Pope and U. S. Military Voice Support for Action on Climate Change

As the Obama administration unveils its plan to slash carbon pollution from U. S. power plants, the leader of the worldwide Catholic Church and former top brass in the U. S. military have each issued proclamations in support of climate protection. In recent weeks, Pope Francis and a group of 16 retired U. S. military…

A Sacred Reunion: The Colorado River Returns to the Sea

After coursing through its delta for nearly eight weeks, the fresh waters of the Colorado River have touched the high tides of the salty sea. It is the first time in sixteen years that the Colorado River, which flows 1,450 miles (2,334 kilometers) from its headwaters in the Rocky Mountains of Colorado  to the Sea…

Gila River Diversion Would Be a Costly Failure

As the December deadline approaches for New Mexico to decide whether or not it will proceed with a controversial diversion of the Gila River, a former director of the state’s Interstate Stream Commission (ISC) testified on April 30 to the ISC that the proposed diversion would result in “a failed project that would produce little…

An Innovative Conservation Fund for the Colorado River

The four largest cities that get their drinking water from the Colorado River are gearing up to pilot an innovative conservation scheme that pays farmers, industries and municipalities to reduce their use of the river’s water. The main aim of the new initiative is to keep the levels of Lake Mead and Lake Powell, the…

Wildfires in the Western U.S. Are on the Rise, Posing Threats to Drinking Water

When the Las Conchas Fire scorched some 151,000 acres of northern New Mexico in 2011, it wasn’t just the direct fire damage that was cause for worry. Striking as it did in the midst of a persistent drought, but just before summer “monsoon” rains, the Las Conchas – the largest blaze in New Mexico’s recorded…

Working Together to Change the Course

Everybody prefers a healthy, flowing river to a dried-up river channel. But in many parts of the world, including much of the western United States, it sometimes appears like we have to dry up our rivers to grow the food we need – that we can’t have productive agriculture and healthy rivers side-by-side. But, in…

Landscapes Transform With the Arrival of the Colorado River

It’s a rare event to see a river literally form before your eyes. But each day that we ventured out to find the leading edge of the Colorado River as it advanced through its delta during this historic “pulse flow,” we were treated to exactly that phenomenon: a dry, sandy channel that hasn’t seen water…

Monitoring the Pulse of the Colorado River

Now in its 14th day, the historic pulse flow coursing through the Colorado River Delta toward the sea is under the careful watch of dozens of scientists who fan out across the landscape to measure and track its vital signs – from flow rates and salinity levels to seed dispersal by native cottonwoods and willows.…

A Colorado Delta Community Reconnects with its River

On Tuesday afternoon, March 25, 2014, word got out that the river was coming. Kids, parents, dogs and teenagers began gathering at the bridge in San Luis Rio Colorado, a border town of about 160,000 people. Young people had never seen the river that gives this town its name flow beneath the bridge. They waited. …

Witnesses to History at Morelos Dam on the Colorado River

A dozen dignitaries faced a crowd of more than two hundred gathered yesterday at Morelos Dam in the Mexican city of Los Algodones, Baja California, to proclaim the release of a “pulse flow” of Colorado River water to its dry delta a momentous occasion for both the river and binational relations. (See “Historic Pulse Flow…