REFERENCE TITLE: Colorado River; cause of decline

State of Arizona

House of Representatives

Fifty-seventh Legislature

First Regular Session

2025

HCR 2046

Introduced by

Representatives Griffin: Diaz, Lopez

A CONCURRENT RESOLUTION

Recognizing forest mismanagement and salt cedars as the principal causes of water depletion of the Colorado River and supporting eradication of these causes.

(TEXT OF BILL BEGINS ON NEXT PAGE)

Whereas, the Colorado River system has experienced declines in annual inflow from runoff; and

Whereas, this reduction in annual inflow has reduced water supplies for people, agriculture and businesses; and

Whereas, the causes of the declines are historic drought, evapotranspiration and salt cedars; and

Whereas, the Colorado River Basin has been in a drought since 2000, resulting in decreased precipitation in the Upper Colorado River Basin watersheds and tributaries that feed the main stem of the Colorado River; and

Whereas, public land managers have allowed forests to grow unnaturally, becoming clogged with far too many trees; and

Whereas, water evaporates from the trees before ever reaching the river; and

Whereas, the United States Bureau of Reclamation estimates that the Colorado River loses almost 4 million acre-feet of water per year to evapotranspiration. Arizona's share of the Colorado River is only 2.8 million acre-feet; and

Whereas, state and federal forest mismanagement has allowed this evapotranspiration to increase, reducing this state's gains in water conservation. More needs to be done to address the overgrown forests in the Colorado River watershed; and

Whereas, the salt cedar tree, also known as the tamarisk, was brought to the United States in the 1800s as an ornamental plant. It is now listed as an invasive species by the United States Department of Agriculture; and

Whereas, this invasive plant out-competes native cottonwood, mesquite and willow, altering the ecology and hydrology of native systems.  One tree can drink more than 200 gallons of water per day; and

Whereas, salt cedar trees have spread across virtually every river system in half of the United States, consuming unfathomable amounts of water; and

Whereas, salt cedars now cover nearly two million acres of river banks; and

Whereas, salt cedars often grow in stands of over 3,000 trees per acre, constituting nearly 672 acre-feet of water consumed per acre per year; and

Whereas, salt cedars remain one of the most difficult of all nonnative species to control and are perhaps the nation's most insidious water problem.  Eradicating them from American rivers would constitute one of the largest water projects in history; and

Whereas, in 2003 and 2006, Congress gave over $50 million to research universities to conduct studies and to nonprofit organizations to conduct demonstration projects, yet salt cedars still thrive; and

Whereas, organizations have raised awareness and made progress in organizing eradication efforts but they are woefully underfunded, raising less than $4 million per year and restoring less than 2,000 acres per year. More needs to be done to address and eradicate salt cedars from the American West.

Therefore

Be it resolved by the House of Representatives of the State of Arizona, the Senate concurring:

1. That consumption is not the problem causing reduction of Colorado River water.

2. That mismanagement of overgrown and water-depleting plants in American watersheds reduces annual flows in the Colorado River.

3. That the Members of the Legislature determine that until the principal causes of the limited Colorado River water are addressed, any proactive conservation efforts or investments that state or private organizations make will be in vain because the gains will be consumed by the additional proliferation of forest stands and salt cedars.

4. That the Members of the Legislature support the focus on eradicating salt cedars and the overgrowth of forests, which would provide substantial volumes of water.

5. That the Members of the Legislature determine that eradicating salt cedars and responsibly managing forests in the West presents an opportunity to substantially increase the availability of water in the Colorado River.