The Colorado River
The Colorado River
Threats to river and delta: Water flow is decreasing. This water serves 30 million people in seven U.S. states and Mexico, with 70 percent of its water siphoned off to irrigate 3.5 million acres of cropland. Possible actions between the United States and Mexico could significantly reduce the flow of water into the delta, increase its salinity, and alter the natural vegetation. Drought has lowered water levels in upstream reservoirs, eliminating the occasional floods the delta needs to maintain and extend the partial recovery of the 1980s and 1990s. The drought has left the Southwest grasping for water. South of Yuma, where the river forms a 23-mile boundary between the United States and Mexico, the International Boundary and Water Commission is considering proposals to straighten the channel and plan for a flood flow of 140,000 cub feet per second. Digging a channel capable of containing that flood level would require removing cottonwoods, willows, and other vegetation from both sides of the river. If this happens, as much as 500 acres of vegetation might be lost. Digging the channels would destroy the richest natural area along the river. The Mesa de Andrade Marshes is home to 75 species of birds, while also providing a lot of greenery amongst the Sonoran Desert. These marshes are not fed by Mexican water though. The water comes from leaking, unlined portions of the All- American Canal in the U.S. It carries Colorado River water from the Imperial Dam west to California’s Imperial and Coachella valleys. The lost water supports the marshes and Mexiali Valley farms. This will change to help California use water more efficiently. The effect would be as significant as drying up the Mesa de Andrade marshes. Water is available, we just have to find a way to get it to the delta.
Environmental and human impacts: In the 1920’s, Western states began portioning out the water by building dams and diverting the flow to Los Angeles, San Diego, Phoenix,
Threats to river and delta: Water flow is decreasing. This water serves 30 million people in seven U.S. states and Mexico, with 70 percent of its water siphoned off to irrigate 3.5 million acres of cropland. Possible actions between the United States and Mexico could significantly reduce the flow of water into the delta, increase its salinity, and alter the natural vegetation. Drought has lowered water levels in upstream reservoirs, eliminating the occasional floods the delta needs to maintain and extend the partial recovery of the 1980s and 1990s. The drought has left the Southwest grasping for water. South of Yuma, where the river forms a 23-mile boundary between the United States and Mexico, the International Boundary and Water Commission is considering proposals to straighten the channel and plan for a flood flow of 140,000 cub feet per second. Digging a channel capable of containing that flood level would require removing cottonwoods, willows, and other vegetation from both sides of the river. If this happens, as much as 500 acres of vegetation might be lost. Digging the channels would destroy the richest natural area along the river. The Mesa de Andrade Marshes is home to 75 species of birds, while also providing a lot of greenery amongst the Sonoran Desert. These marshes are not fed by Mexican water though. The water comes from leaking, unlined portions of the All- American Canal in the U.S. It carries Colorado River water from the Imperial Dam west to California’s Imperial and Coachella valleys. The lost water supports the marshes and Mexiali Valley farms. This will change to help California use water more efficiently. The effect would be as significant as drying up the Mesa de Andrade marshes. Water is available, we just have to find a way to get it to the delta.
Environmental and human impacts: In the 1920’s, Western states began portioning out the water by building dams and diverting the flow to Los Angeles, San Diego, Phoenix,