Seven states signed the historic Colorado River Compact a century ago last week.

The Compact provided a framework for fair sharing of the then-estimated 17.5 million annual acre-feet of water flowing past Lee Ferry, Nevada, located between Glen Canyon National Recreation Area and the Grand Canyon.

The agreement has been hotly debated in 2022 as drought conditions have greatly depleted the river’s water supply.

“Most of the Basin states were anxious about securing their share of the Colorado River but could not agree on how to allocate the river among themselves,” according to the Water Education Foundation.

The river today serves more than 40 million people with water for agriculture, electricity generated by the Glen Canyon and Hoover Dam power stations, as well as habitat conservation and recreation.

The Compact divided it into the Upper Basin — composed pf Colorado, New Mexico, Utah and Wyoming — and the Lower Basin, composed of Arizona, California and Nevada.

The historic flows have varied from 4.4 million acre-feet to more than 22 million acrefeet annually, sometimes making it impossible to meet the 7.5 million acre-feet allotted to the Upper and Lower basins.

In 1922, California’s population was a smidgen under 4 million, and upstream states were worried that — under the doctrine of prior appropriation — California might lay claim to the lion’s share of water that was the mainstay of agriculture in Colorado and downstream states.

Colorado’s population in 1922 was just over 1 million. Today, Colorado has 5.8 million people and California has 39.2 million, just shy of eight times Colorado’s population.

In January 1922, the Colorado River Commission convened in Washington, D.C. Herbert Hoover, then-secretary of commerce who was later elected president in 1929, was its chairman. No agreement was reached at that meeting.

In June 1922, the U.S. Supreme Court ruled that whoever used the water first had the first right of use in perpetuity, regardless of state lines, even if there was insufficient water to serve everyone.

Pressured by the Supreme Court ruling, delegates met again beginning Nov. 9, 1922, in New Mexico and eventually hammered out the Compact. It was signed at the Palace of the Governors in Santa Fe on Nov. 24.

In the ensuing century, the river has been dammed, divided and diverted to the extent that today little water — sometimes no water at all — eventually ends up in Mexico. The Mexican Water Treaty of 1944 allocated only 1.5 million acre-feet of water annually from the Colorado River.

Today, the river is in greater peril than it has been in more than 1,000 years due to an unprecedented 23-year drought that continues to sap flows year after year, imperiling the Compact as states jockey for water.

The U.S. Department of Interior recently stepped in and called for more cooperation between the Compact states, warning that water levels in Lake Mead and Lake Powell are so low that power generation may have to be curtailed.

That would devastate the Lower Basin states and particularly 12 cities in the Los Angeles area, which get roughly 56% of the electricity generated by the Hoover Dam.