Defining the Geopolitics of a Thirsty WorldSM
The West’s Race To Secure Water

Via Bloomberg, a report on how four cities in the U.S. are trying to survive future droughts, from expanding reservoirs and tapping neighboring watersheds to pushing conservation efforts:

How much water flows into Southwestern U.S. cities next year will depend on the coming snowfall and the resulting snowpack accumulation. So far, it’s not looking good.

High mountain snows, the source of most of the region’s water supplies, are projected to be lower than usual this winter in the Southern Rockies. This means that come spring, forecasters expect less snowmelt to flow into the Colorado River Basin and other nearby watersheds. In addition, a warming climate is causing accumulated snow to melt earlier and faster than before, with no guarantee that water will last until next season’s thaw.

Even though localities store the melted snow in mountain reservoirs, sometimes there’s just not enough. Many cities aren’t prepared for the water scarcity that lies ahead—their infrastructure isn’t built to handle sustained droughts or withstand an increasing number of wildfires that are magnified by a lack of rainfall.

While parts of California’s Sierra Nevada mountains have seen heavy rain and snow recently, other areas in the West remain parched. Here are four cities’ strategies for managing water scarcity.

 

Denver, Colorado

Denver’s chief water utility collects rain and snow across a 4,000-square-mile area, capturing about 94 billion gallons in an average year—enough to fill the Denver Broncos’ football stadium almost 157 times.

Since half of Denver’s drinking water comes from tributaries of the Colorado River on the west side of the Rocky Mountains—and the river basin has experienced a megadrought for the last two decades—the city is preparing for a future of increasing scarcity by diversifying its water sources and ramping up its conservation and efficiency programs.

“The approach is similar to an investment portfolio—diversity of supply, and of different strategies for how we provide water service,” said Jim Lochhead, Denver Water’s chief executive officer.

Only 20% of the precipitation in the state of Colorado falls east of the Rocky Mountains and onto the South Platte River watershed, according to Denver Water. The remaining 80% falls on the western side of the mountains, in the Colorado River basin catchment area. As a result, Denver has had to move water from west to east to provide for the roughly 1.5 million people living in the city and some of its suburbs.

Agricultural and municipal water users on the western side of the Rockies have criticized the city’s water management plans.

But the city has also been a pioneer in water efficiency programs, Lochhead said, noting that Denver Water uses about 2% of the water in the state to support 25% of Colorado’s population. It provides rebates for residents who buy higher-efficiency toilets and sprinklers, enforces limits on summertime lawn watering, and participates in the Environmental Protection Agency’s WaterSmart program.

It’s also investing in increasing water storage and making infrastructure upgrades, with a capital plan for the next 10 years of about $2.6 billion. The utility operates facilities in 12 counties—20 dams, 15 surface water reservoirs, more than 20 pump stations, 3 water treatment plants, and more than 3,000 miles of distribution pipe—enough to stretch from Los Angeles to New York.

The city’s biggest water project on the books, an estimated $464 million expansion of Gross Reservoir west of Boulder, is moving ahead after objections from neighboring Boulder County. The dispute was settled in November, after Denver Water agreed to mitigate greenhouse gas emissions and environmental damage expected from raising the reservoir’s dam—in addition to paying Boulder County $12.5 million.

“Denver Water’s plan to build the tallest dam in Colorado history will hurt the 40 million people in seven states and two countries who depend on the Colorado River for their water supply,” said Daniel E. Estrin, general counsel and advocacy director at Waterkeeper Alliance.

Phoenix, Arizona

Hot, dry, and in the center of a desert, Phoenix has been preparing for drought for decades.

“It’s a given in the Sonoran Desert that one or more of our water resources will be challenged by drought,” said Cynthia Campbell, water resource management adviser for the City of Phoenix. “For that reason, we have to have water resources that exceed what we need to deliver to our customers in any given year.”

But population growth creates an additional challenge—according to census data, Phoenix experienced the largest increase in population in the U.S. between 2010 and 2020. Its water utility, Phoenix Water, serves about 1.5 million customers across 540 square miles with more than 7,000 miles of pipeline.

Phoenix relies on water supplies from four primary sources. The canals of the Salt River Project bring water from the Salt and Verde watersheds, while the Central Arizona Project connects the city with the Colorado River. Groundwater and reclaimed water make up the rest, according to the city’s 2021 water resource plan.

The Central Arizona Project—a 336-mile canal that diverts billions of gallons of water out of the Colorado River every year and pumps it to central and southern Arizona—will take the bulk of water cuts coming to the state in 2022 after the Bureau of Reclamation declared shortage conditions in the Colorado River Basin. This year was the first time a shortage was declared in the almost 100-year history of the Colorado River Compact, which governs water allotments to the seven states in the basin.

Water customers pay a flat monthly amount, but their bills can soar if they use more, which has the effect of discouraging water use for residential landscaping, Frankel said.

“You discourage waste with higher rates,” Frankel said. “We need more of that to sustain this fragile water supply in a climate change era.”

In October, the first of two rate increases will kick in to pay for rehabilitating and replacing water pipes, treatment plants, pumps, reservoirs and wells to deliver the city’s drinking water.

Phoenix also is investing in new infrastructure to move water supplies to portions of its system normally served by the Colorado River. The 66-inch “Drought Pipeline,” scheduled for completion in 2023, will supply water from the Salt and Verde watersheds in the south part of the city to areas in the north affected by shortages on the Colorado.

Grand Junction, Colorado

Nestled in a high-desert valley along the Colorado River, quickly-growing Grand Junction, Colorado, population 65,000, according to the 2020 census, has long been seen as a water-rich city in a water-scarce area at the heart of the West’s extreme drought.

“But the last few years have started to show me that we’re possibly not as invulnerable—not quite as sheltered as I might have thought we were,” said Hannah Holm, director of the Water Center at Colorado Mesa University.

Grand Junction represents growing cities throughout the West that have staked the future of their water supply on what the climate was like over the last century. But climate change has made that unrealistic.

The city gets most of its water from mountain streams fed by runoff from thawing snowpack. But temperatures are rising, leaving the city’s watershed drier and more vulnerable to wildfire. Wildfires can destroy water infrastructure and ash can affect water quality and treatment costs.

Grand Junction’s water comes from nearby Grand Mesa, the world’s largest flat-topped mountain. In a pinch, the city can obtain water from neighboring suppliers—the biggest of which, the Ute Water Conservancy District, also gets its water from Grand Mesa. The third draws water directly from the Colorado River.

The city is preparing for drought and wildfire by expanding its interconnections with its neighbors, but the bulk of the water will still come from the mesa, said Grand Junction Utilities Director Randi Kim.

“The likelihood of the entire Grand Mesa burning is fairly low,” she said. “It would likely be portions of the Grand Mesa, which might affect one watershed or the other.”

But Colorado’s recent wildfires have been enormous. The 2020 Cameron Peak Fire, the largest in the state’s history, incinerated an area larger than New York City, including the entire primary watershed for Fort Collins, Colorado.

A warning for what may lay ahead for Grand Junction came last year, when the Pine Gulch Fire scorched an area nearly the size of Chicago just outside of Grand Junction. It burned in elevations lower than the city’s watershed, but other recent fires in Colorado have spread regardless of high altitudes. 

St. George, Utah

Washington County, Utah, and its seat, St. George, were in the bullseye of a 20-year megadrought that became so extreme in 2021 that Utah Governor Spencer Cox in June declared a weekend of prayer for the divine to intervene with sheets of rain.

The county represents a nexus of extreme growth and climate change-driven long-term water scarcity. With its mild climate and proximity to national parks and Las Vegas, the county is expected to have the most rapid growth in the state. By 2065, its population is expected to jump by 229% to more than 500,000 people. And, with some of the region’s lowest water rates, it’s cheap to use a lot of it.

But climate change is making the county’s main water source, the Virgin River, less predictable and less stable as it courses down from the mountains above Zion. It can’t keep up with growth and drought.

So county officials are looking for new water to tap. Their answer: a proposed 140-mile underground pipeline that would siphon water from Lake Powell, a reservoir on the Colorado River. Zach Renstrom, general manager of the Washington County Water Conservancy District, says the lake is more reliable because its watershed is large, spanning four states, and a pipeline would give the county another tool it can use to ensure drinking water.

But Lake Powell’s future also is uncertain because of the drought and growing demand for Colorado River water from California and Arizona. This year, the Biden administration declared a first-ever water shortage in the Colorado River Basin.

The St. George area represents a lot of the West: “You have places that are better endowed with water than others, and what we’ve seen in the growth patterns is that development and population growth do not necessarily occur in the locations with the most reliable water supplies,” said Peter Mayer, principal at the water consultancy Water Demand Management.

The pipeline, he said, would have junior water rights on the Colorado River and would be one of the first to be curtailed as water across the river’s seven-state basin evaporates.

Mayer authored a June report showing how the pipeline is unnecessary because Washington County could drastically reduce its water use, store excess water from the Virgin River for use in dry years, reuse its wastewater and more effectively manage water demand.

“If the people in Washington County were to use water the same way as in Denver, Albuquerque or Los Angeles, they could grow to the size they have dreams of and rely on their local water supply,” Mayer said.



This entry was posted on Saturday, December 25th, 2021 at 5:17 am and is filed under Colorado River, United States.  You can follow any responses to this entry through the RSS 2.0 feed.  Both comments and pings are currently closed. 

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