#ClimateChange is destabilizing the #ColoradoRiver Basin. Where do we go from here? — Environmental Defense Fund #COriver #aridification

From the Environmental Defense Fund (Christopher Kuzdas):

In June, a portion of my neighborhood in Flagstaff, Arizona, was put on pre-evacuation notice due to a nearby wildfire. A few weeks later, storms dumped heavy rains over a burn scar from a 2019 fire that caused destructive floods through parts of town. So far, this summer has been our third-wettest monsoon season on record, a complete contrast from our two driest monsoon seasons on record in 2019 and 2020.

These extremes are just a few local examples of the havoc that climate change is causing around the world. Here in the West, we are now in uncharted territory with the first-ever shortage declaration on the Colorado River.

What the shortage declaration means

The U.S. Bureau of Reclamation recently confirmed the Colorado River will be operated under never-before-used shortage rules, called a “tier 1” shortage, starting in 2022.

Under the rules defined by the 2019 Drought Contingency Plan (DCP), other agreements and the river’s operating guidelines, Arizona will absorb the brunt of this shortage. About one-third less water will flow through the Central Arizona Project canal to the Phoenix and Tucson areas, primarily impacting farmers. Nevada and Mexico will also see mandatory but smaller water cuts.

Though overused and overallocated, the Colorado River still provides water for 40 million people in the United States, Mexico and 30 Native American tribes. Water use across the Colorado River Basin has been unsustainable for years, and it was set up to be that way, going back to the 1922 Colorado River Compact that divided up the river. But climate change is now magnifying and accelerating problems in the basin. Photo credit: The Environmental Defense Fund

Even more concerning are water supply projections for 2023 and beyond.

Bureau of Reclamation projections forecast Lake Mead could fall close to a threshold where there are no rules outlining additional water cuts to avoid a crash to dead pool — when no water can flow out of Hoover Dam. This risk of an acceleration in plummeting water levels — which also jeopardizes water levels in Lake Powell — has prompted basin state representatives to initiate meetings to discuss additional actions that might be needed if water levels in Lake Mead fall below 1,020 feet.

It will get hotter and drier

This unprecedented situation offers a glimpse into our future. Warming scenarios from the latest IPCC report suggest that we could exceed 2 degrees Celsius of warming around midcentury, with more than 5 degrees by the end of the century, in the absence of action to curb carbon emissions.

Brad Udall: Here’s the latest version of my 4-Panel plot thru Water Year (Oct-Sep) of 2019 of the #coriver big reservoirs, natural flows, precipitation, and temperature. Data goes back or 1906 (or 1935 for reservoirs.) This updates previous work with @GreatLakesPeck

Why does this matter for the Colorado River? Colorado River flows are highly sensitive to warming, and aridification caused by climate change is already reducing the water flowing in the river. With each additional 1 degree Celsius (1.8 degrees Fahrenheit) of warming, the Colorado River’s average flow drops by 9.3%, according to the U.S. Geological Survey. Colorado River flows could be up to one-third less than the current average within a generation, unless meaningful and immediate reductions in carbon emissions are achieved.

The outlook for the Colorado River is overwhelming. But what our future looks like is still our choice. We can, and should, choose to pursue a just transition to a basin with significantly less water. While in no way comprehensive, below are four ways to get started on that path.

1. Reconcile water demand with our climate reality.

Reconciling demands with our climate reality, at the very least, will involve updating river operating rules, scaling up conservation programs and shifting away from outdated expansionism.

The rules that determine how we balance supply and demand, and the underlying rights and agreements that collectively determine who gets how much water and when, will play a major role in how we transition to a basin with less water.

River operating rules have become more flexible to some extent as they evolved through new agreements like the DCP. However, current river operating rules still don’t account for the full suite of climate change impacts, especially those impacts under more dire climate scenarios. While river operating rules are already a focus of discussion, updating them will require thoughtful leadership, as well as attention to climate and other social and environmental considerations.

Scaling up conservation programs such as system conservation in the Lower Basin and demand management in the Upper Basin will also play an important role. If not for water conserved in Lake Mead, a “tier 1” shortage would have occurred years ago. Our challenge moving forward will be expanding the scale and impact of these programs, and in the Upper Basin, moving much faster to do so.

To fully reconcile demands with our climate reality, we must also finally shift away from legacy expansionism and boosterism that still show up through unnecessary project proposals like the Lake Powell Pipeline. We can do more with less.

Lake Mead water levels have dropped to a record low. Overall water use must also go down, and it must go down significantly to meet our climate reality. Photo: Chris Richards/Flickr (CC BY-NC-ND 2.0) via Audubon

2. Address long-standing inequities.

Long-standing inequities should be addressed to ensure water security for all. Two of the many considerations are inclusive decision-making and fully recognizing tribal water rights.

Inclusive and transparent processes to make decisions are essential to developing solutions that account for multiple values and goals. In the past, decision-making was often exclusive and responded primarily to a narrow set of private interests. That is changing.

From the 2018 Tribal Water Study, this graphic shows the location of the 29 federally-recognized tribes in the Colorado River Basin. Map credit: USBR

For example, Arizona’s DCP process included some tribes and conservation groups, and the process would not have been successful without the leadership of the Gila River Indian Community and the Colorado River Indian Tribes. More diversity at the table enables more creativity and better solutions.

Although the Colorado River Basin’s 30 sovereign Native American tribes have unique rights and claims to a significant portion of the Colorado River’s flow, not all are using their water for several reasons. Those reasons include aging or inadequate infrastructure; limited funding; and significant legal, policy and administrative barriers.

Overcoming such barriers to accessing Colorado River water and confirming and fulfilling tribal water rights will be critical for many tribes to achieve goals such as meeting basic water needs and securing livelihoods. Addressing those barriers is a step toward dealing with long-standing inequity and should be a priority for policymakers.

3. Take a whole-portfolio approach.

A whole-portfolio approach includes new watershed-focused actions to support communities in adapting to and mitigating the steadily compounding risks and extremes of climate change. The recently published Ten Strategies for Climate Resilience report describes a suite of local and watershed-scale projects to do just that, including forest health and restoration, naturally distributed storage, regenerative agriculture and new crop markets.

A whole-portfolio approach also necessitates adequate management and planning for our other water supplies. However, that’s not fully possible across a large part of the basin without changes in state-level water law and policy. For example, Arizona, which makes up almost half the landmass of the Colorado River Basin, already depends on groundwater for 40% of its annual water supply and will only become increasingly dependent on groundwater as Colorado River flows shrink. Arizona does not manage groundwater across most of the state, and local rural communities have little to no power to do so.

Changing this free-for-all approach to groundwater in rural Arizona is critical if we hope to have a water-secure future for all people in the basin.

4. Lead on climate.

More warming means less water in the Colorado River Basin. How much water dries up depends on how fast we can get off fossil fuels. Across the basin, and globally, freshwater agendas must start including actions to stop heating the planet. Climate leadership is water leadership.

The road ahead is difficult. But what our shared future looks like in the Colorado River Basin is our own choice. Let’s choose to collectively pursue a just transition to a basin with less water.

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