In a drought, California is watching water wash out to sea

Read the full story in the New York Times.

Heavy storms have flooded parts of California, but the state has been unable to capture billions of gallons of water that are flowing unchecked into the ocean. Los Angeles is embarking on an ambitious new program to change that.

How California could save up its rain to ease future droughts — instead of watching epic atmospheric river rainfall drain into the Pacific

Heavy rain from a series of atmospheric rivers flooded large parts of California from late December 2022 into early January 2023. Tayfun Coskun/Anadolu Agency via Getty Images

by Andrew Fisher, University of California, Santa Cruz

California has seen so much rain over the past few weeks that farm fields are inundated and normally dry creeks and drainage ditches have become torrents of water racing toward the ocean. Yet, most of the state remains in drought.

All that runoff in the middle of a drought begs the question — why can’t more rainwater be collected and stored for the long, dry spring and summer when it’s needed?

As a hydrogeologist at the University of California at Santa Cruz, I’m interested in what can be done to collect runoff from storms like this on a large scale. There are two primary sources of large-scale water storage that could help make a dent in the drought: holding that water behind dams and putting it in the ground.

Why isn’t California capturing more runoff now?

When California gets storms like the atmospheric rivers that hit in December 2022 and January 2023, water managers around the state probably shake their heads and ask why they can’t hold on to more of that water. The reality is, it’s a complicated issue.

California has big dams and reservoirs that can store large volumes of water, but they tend to be in the mountains. And once they’re near capacity, water has to be released to be ready for the next storm. Unless there’s another reservoir downstream, a lot of that water is going out to the ocean.

A video captures flooding from record rainfall on the last weekend of 2022.

In more populated areas, one of the reasons storm water runoff isn’t automatically collected for use on a large scale is because the first runoff from roads is often contaminated. Flooding can also cause septic system overflows. So, that water would have to be treated.

You might say, well, the captured water doesn’t have to be drinking water, we could just use it on golf courses. But then you would need a place to store the water, and you would need a way to distribute it, with separate pipes and pumps, because you can’t put it in the same pipes as drinking water.

Putting water in the ground

There’s another option, and that’s to put it in the ground, where it could help to replenish groundwater supplies.

Managed recharge has been used for decades in many areas to actively replenish groundwater supplies. But the techniques have been gaining more attention lately as wells run dry amid the long-running drought. Local agencies have proposed more than 340 recharge projects in California, and the state estimates those could recharge an additional 500,000 acre-feet of water a year on average if all were built.

One method being discussed by the state Department of Water Resources and others is Flood-MAR, or flood-managed aquifer recharge. During big flows in rivers, water managers could potentially divert some of that flow onto large parts of the landscape and inundate thousands of acres to recharge the aquifers below. The concept is to flood the land in winter and then farm in summer.

Illustration showing different techniques with fields flooded in different ways
Flood-managed aquifer recharge methods. California Department of Water Resources

Flood-MAR is promising, provided we can find people who are willing to inundate their land and can secure water rights. In addition, not every part of the landscape is prepared to take that water.

You could inundate 1,000 acres on a ranch, and a lot of it might stay flooded for days or weeks. Depending on how quickly that water soaks in, some crops will be OK, but other crops could be harmed. There are also concerns about creating habitat that encourages pests or risks food safety.

Another challenge is that most of the big river flows are in the northern part of the state, and many of the areas experiencing the worst groundwater deficits are in central and southern California. To get that excess water to the places that need it requires transport and distribution, which can be complex and expensive.

Encouraging landowners to get involved

In the Pajaro Valley, an important agricultural region at the edge of Monterey Bay, regional colleagues and I are trying a different type of groundwater recharge project where there is a lot of runoff from hill slopes during big storms.

The idea is to siphon off some of that runoff and divert it to infiltration basins, occupying a few acres, where the water can pool and percolate into the ground. That might be on agricultural land or open space with the right soil conditions. We look for coarse soils that make it easier for water to percolate through gaps between grains. But much of the landscape is covered or underlain by finer soils that don’t allow rapid infiltration, so careful site selection is important.

One program in the Pajaro Valley encourages landowners to participate in recharge projects by giving them a rebate on the fee they pay for water use through a “recharge net metering” mechanism.

How recharge net metering works.

We did a cost-benefit analysis of this approach and found that even when you add in all the capital costs for construction and hauling away some soil, the costs are competitive with finding alternative supplies of water, and it is cheaper than desalination or water recycling.

Is the rain enough to end the drought?

It’s going to take many methods and several wet years to make up for the region’s long period of low rainfall. One storm certainly doesn’t do it, and even one wet year doesn’t do it.

For basins that are dependent on groundwater, the recharge process takes years. If this is the last rainstorm of this season, a month from now we could be in trouble again.

Andrew Fisher, Professor of Earth and Planetary Sciences, University of California, Santa Cruz

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Planning for dry times: The West considers more reservoirs and aquifers

Read the full story at Stateline.

As parched California receives much needed rain and snow this winter, some local water officials are calling on state leaders to invest in new infrastructure projects that will store freshwater for inevitable dry times to come.

The worst megadrought in 1,200 years is devastating the water supply in the Western United States. It’s drying up the Colorado River basin, a major North American river system, while also depleting reservoirs and underground aquifers and forcing communities to make drastic cuts to their freshwater use.

Western states can no longer rely on snowmelt and rain to supply their communities in a drier, more arid landscape caused by climate change, say water experts.

Environmental groups have called for increased conservation efforts, such as pushing people to limit watering of ornamental lawns and upgrade to more efficient appliances. And they want officials to invest more in wastewater recycling or desalination projects. But some local water officials in California and across the West see a massive opportunity in storing rainwater in new or expanded reservoirs and groundwater aquifers.

Fish kills may result from low water in backwaters of the Mississippi

Read the full story from WVIK.

Low water levels on the Upper Mississippi River in the Quad Cities area may affect fish this winter and next year.

Salt Lake City’s efforts to fight pollution face a new challenge: Toxic dust

Read the full story from NBC News.

Declining water levels exposed much of the Great Salt Lake’s bed and created conditions for storms of dust laden with toxic metals that now threaten 2 million people.

What is a flash drought? An earth scientist explains

Weeds grow on the dried-out floor of the Hoppin Hill Reservoir in North Attleboro, Mass., on Aug. 3, 2022. AP Photo/Charles Krupa

by Antonia Hadjimichael, Penn State

Many people are familiar with flash floods – torrents that develop quickly after heavy rainfall. But there’s also such a thing as a flash drought, and these sudden, extreme dry spells are becoming a big concern for farmers and water utilities.

Flash droughts start and intensify quickly, over periods of weeks to months, compared to years or decades for conventional droughts. Still, they can cause substantial economic damage, since communities have less time to prepare for the impacts of a rapidly evolving drought. In 2017, a flash drought in Montana and the Dakotas damaged crops and grasses that served as forage for cattle, causing US$2.6 billion in agricultural losses.

Flash droughts also can increase wildfire risks, cause public water supply shortages and reduce stream flow, which harms fish and other aquatic life.

Less rain, warmer air

Flash droughts typically result from a combination of lower-then-normal precipitation and higher temperatures. Together, these factors reduce overall land surface moisture.

Water constantly cycles between land and the atmosphere. Under normal conditions, moisture from rainfall or snowfall accumulates in the soil during wet seasons. Plants draw water up through their roots and release water vapor into the air through their leaves, a process called transpiration. Some moisture also evaporates directly from the soil into the air.

Graphic showing precipitation, evaporation and transpiration between soil and the atmosphere
Water constantly circulates between soil and the atmosphere – sometimes directly, sometimes via plants. USGS

Scientists refer to the amount of water that could be transferred from the land to the atmosphere as evaporative demand – a measure of how “thirsty” the atmosphere is. Higher temperatures increase evaporative demand, which makes water evaporate faster. When soil contains enough moisture, it can meet this demand.

But if soil moisture is depleted – for example, if precipitation drops below normal levels for months – then evaporation from the land surface can’t provide all the moisture that a thirsty atmosphere demands. Reduced moisture at the surface increases surface air temperatures, drying out the soil further. These processes amplify each other, making the area increasingly hot and dry.

Moist regions can have flash droughts

Flash droughts started receiving more attention in the U.S. after notable events in 2012, 2016 and 2017 that reduced crop yields and increased wildfire risks. In 2012, areas in the Midwest that had had near-normal precipitation conditions through May fell into severe drought conditions in June and July, causing more than $30 billion in damages.

New England, typically one of the wetter U.S. regions, experienced a flash drought in the summer of 2022, with areas including Boston and Rhode Island receiving only a fraction of their normal rainfall. Across Massachusetts, critically low water levels forced towns to issue mandatory water restrictions for residents.

Planning for flash droughts in a changing climate

Conventional droughts, like the Dust Bowl of the 1930s or the current 22-year drought across the southwestern U.S., develop over periods of years. Scientists rely on monitoring and prediction tools, such as measurements of temperature and rainfall, as well as models, to forecast their evolution.

Predicting flash drought events that occur on monthly to weekly time scales is much harder with current data and tools, largely due to the chaotic nature of weather and limitations in weather models. That’s why weather forecasters don’t typically make projections beyond 10 days – there is a lot of variation in what can happen over longer time spans.

And climate patterns can shift from year to year, adding to the challenge. For example, Boston had a very wet summer in 2021 before its very dry summer in 2022.

Scientists expect climate change to make precipitation even more variable, especially in wetter regions like the U.S. Northeast. This will make it more difficult to forecast and prepare for flash droughts well in advance.

But new monitoring tools that measure evaporative demand can provide early warnings for regions experiencing abnormal conditions. Information from these systems can give farmers and utilities sufficient lead time to adjust their operations and minimize their risks.

Antonia Hadjimichael, Assistant Professor of Geosciences, Penn State

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Hard truths about California’s water crisis

Read the full story from FERN.

Last month, Jay Lund, a distinguished professor of civil and environmental engineering at UC Davis, wrapped up a lecture on California’s drought with a slide titled, “Resistance is Futile.” It included a list of his predictions about the state’s water crisis, some ofwhich bordered on apocalyptic. As climate change fuels extreme drought, heat and flooding, Lund explained, some of California’s native species will become unsustainable in the wild. Farmers, government agencies and environmental groups will continue to fight over dwindling water supplies. In the San Joaquin Valley, farmers could be forced to fallow 40 percent of their land. “These things will happen,” says Lund, who has been studying California’s water situation for over 30 years. “I don’t see anybody being willing to spend enough money to completely reverse these trends.” 

I spoke with Lund recently about his predictions. Our conversation focused on the San Joaquin Valley, which is one of the most productive agricultural regions in the world. Historic drought has jeopardized many farmers’ water access, and they’ve increasingly relied on groundwater instead. Many farmers have been over-pumping aquifers for years, and a new state law might finally put a stop to it, restricting agricultural water even further. Farming has also wreaked havoc on California ecosystems, and environmental groups are fighting the industry’s diversion of water from rivers and reservoirs in an effort to save salmon and other native fish. This interview has been edited for length and clarity.

Record lows reveal magic of Mississippi River’s sunken past

Read the full story at the Daily Memphian.

The Mississippi River has hit historic lows during a period of intense drought. It’s impacting barge traffic, threatening drinking water downriver and creating a dire situation for farmers throughout the basin. 

It’s also revealing the river’s sunken past.

Century-old artifacts are surfacing, and some natural landmarks are visible for the first time in decades. People are flocking to the river to see for themselves before the water rises and buries it again. 

Gripped by drought, drenched by rain, Mississippi River basin sees climate extremes

Read the full story at Wisconsin Watch.

States across the Mississippi River basin are experiencing drought more commonly found in the arid Southwest, federal data shows. As of Oct. 20, nearly two-thirds of Wisconsin’s land was experiencing at least “abnormally dry” conditions, while swaths of western and northern Wisconsin saw moderate to severe drought, according to the U.S. Drought Monitor.

The dryness has disrupted agriculture, beached barges and upset ecosystems across large swaths of the Midwest, Great Plains and beyond, in epic proportions.

Mayors call for federal assistance as Mississippi River reaches record lows

Read the full story at WWNO.

Mayors along the Mississippi River are asking for more federal help as the drought that has plagued the nation’s water superhighway in recent weeks drags on.

City leaders shared wide-ranging impacts of dry conditions at a Tuesday press conference hosted by the Mississippi River Cities and Towns Initiative, from barge slowdowns to water main breaks caused by shifting dry ground.