AZ Legislature Urges Study Of Harvesting Mississippi Floodwaters For Colorado River

Colorado River [Photo courtesy Arizona Department of Water Resources]

On Tuesday, the Arizona Legislature called on the U.S. Congress to fund a feasibility study for the development of a dam and pipeline to harvest floodwater from the Mississippi River to replenish the Colorado River.

The request took the form of House Concurrent Memorial (HCM) 2004, sponsored by Rep. Tim Dunn. The proposal outlined in the Memorial authorizes the official legislative communication – commonly referred to as a “postcard to Congress,” was passed on Tuesday with a vote of the Arizona Senate.

Dunn’s bill outlines that if it’s shown to be feasible, the U.S. Congress is urged to implement the diversion dam and pipeline as a partial solution to the water supply shortage in Lake Powell and Lake Mead and the flood damage that occurs along the Mississippi River.

HCM 2004 directs the Arizona Secretary of State to transmit copies of the Memorial to the President of the U.S. Senate, the Speaker of the U.S. House of Representatives, the Governors of the Mississippi River states of Arkansas, Illinois, Iowa, Kentucky, Louisiana, Minnesota, Mississippi, Missouri, Tennessee and Wisconsin, and to each member of Congress from the State of Arizona.

In Arizona, water from the Colorado River enters the Central Arizona Project canal to reach the cities of Phoenix and Tucson. Under the 2019 Drought Contingency Plan, Arizona is already taking cuts to its CAP supply.

The state’s junior rights mean its Colorado River supply is more vulnerable than other states.

The question as to how much water can the Colorado River reliably produce into the future is at the core of all of plans.

“Arizona has long been at the forefront among western states in supporting the development and implementation of pioneering, well-reasoned water management policies,” Dunn said in a press release. “Arizona and the other six Colorado Basin states are in the twentieth year of severe drought and experiencing a severe water shortage. Water levels are critical levels, jeopardizing the water delivery and power generation. A new water source could help augment Colorado River supplies. One promising possibility involves piping water that is harvested from Mississippi River flood waters. Diverting this water, which is otherwise lost into the Gulf of Mexico, would also help prevent the loss of human life and billions in economic damages when such flooding occurs. This concept is already being proven in Denver, where floodwater is being successfully harvested from the Missouri River to help alleviate its water shortage.”