Drought, human-caused climate change, invasive species and a “legacy” of environmental problems are permanently altering the California landscape and putting some communities and ecosystems at increasing risk, a group of experts said recently. to water managers.
Invasive species and decades of disruption from massive land and water developments are partly responsible for a continuing decline in California’s native species, experts told the California Water Commission Nov. 16. owned wells, face disproportionately contamination and water scarcity amid recurring cycles of drought, experts said.
Although droughts in California date back to prehistoric times, the state’s modern water problems are the repercussions of decades of decisions, said Jay Lund, professor of civil and environmental engineering at UC Davis.
“A lot of our current environmental problems are really legacies,” he said. We are witnessing “the dynamics of past impacts and past changes taking place and our inability – both in terms of regulatory and economic policy, and practically in some cases with certain invasive species – to manage that apart from legacy impacts “.
Groundwater and the Sacramento-San Joaquin River Delta are also among the areas most vulnerable to dry spells, according to Lund, who pointed out that although cities and agriculture are relatively prepared and well insulated from the impacts of drought, irrigated agriculture must shrink between half a million to 2 million acres to be sustainable.
About 5.5 million of California’s roughly 40 million people live in rural counties, which make up more than half of the state’s land mass. While urban areas like Los Angeles are under mandatory drought restrictions to reduce pressure on state reservoirs, many rural residents who rely on groundwater wells are without water. Water affordability and lack of potable water, especially in the Central Valley and Central Coast, compound the problem.
“We know these challenges disproportionately impact low-income and Latino communities,” said Justine Massey, policy manager and attorney at the Community Water Center. “People who rely on private wells in particular are significantly affected because often they don’t know if their water is safe to drink because no other entity does water testing, nor do they know until they begin to have pumping problems. may approach water levels that will render their well inoperative.
While state legislation like the Sustainable Groundwater Management Act aims to regulate water availability and will help alleviate water scarcity in increasingly arid California, thousands of people and ecosystems tricky ones will slip through the cracks.
A 2020 study commissioned by the Water Foundation found that under the SGMA’s minimum water threshold plans, between 4,000 and 12,000 wells will partially or completely dry up by 2040 in the San Valley alone. Joaquin – affecting approximately 46,000 to 127,000 Californians who could lose access to their current water supply.
“We really urge all decision makers involved… to look at worst-case scenarios and really plan for this, because that’s what we’re going through so far – worst-case after worst-case after worst-case” , Massey said. “And the people most affected are those who contributed the least to the problem.”
Climate change is increasingly recognized as a ‘threat multiplier’ that will accelerate and deepen instability and insecurity around the world. In drought-stricken California, as groundwater levels drop due to less rainfall and overpumping, concentrations of contaminants in the water are rising, Massey said.
The current and future health of California’s ecosystems is also at stake.
Mild, short-term impacts of drought can result in reduced plant growth, but when dry spells are longer and harsher and groundwater depletion is more severe, widespread mortality of habitats and species can occur, said Melissa M. Rohde, director of Rohde Environmental Consulting. , LLC.
“If groundwater demand is high, groundwater can quickly become out of reach of plant roots and rivers, as these ecosystems rely on shallow groundwater,” she said.
Rhode referenced the Nature Conservancy’s Shallow Groundwater Estimation Tool, which found that 44% of the state’s ecosystems were affected by a significant, long-term decline in groundwater between 1985 and 2019. .two decades,” she said.
Under the SGMA, 87% of ecosystems and 40% of groundwater-dependent sinks exist outside of legislation, Rhode said, and “one of the most disconcerting aspects of that is that…these ecosystems are often the last refuge for federal and state authorities of threatened and endangered species.These are very important biological hotspots, and if we don’t do what we can to protect them under the SGMA, we let’s not protect our most vulnerable species.
Drought conditions and extreme heat fueled by climate change have also pushed the Chinook salmon on the verge of extinction.
The fish – which once swam up the Sacramento River to spawn in its cold waters before the Shasta Dam was completed in 1945 – struggled to survive even with government intervention. Last year, the water flowing from Shasta Dam was so hot that most of the eggs and young salmon died.
Forest fires, drought and bark beetle infestations are also destroying the forests of the southern Sierra Nevadawhich could have disastrous consequences for protected species like spotted owls and Pacific fishermen who depend on mature tree canopies for their habitat.
But refusing to accept these changes is pointless, Lund said. “Resistance is futile. We are going to have a future that is going to be different,” and learning to reconcile our ecosystems with human activity will be an ongoing challenge. “How do you manage your native species when everything else changes is going to be a great conundrum for all of our agencies and all of the people trying to do this,” he said.
So what can we do about it? For ecosystems, integrating them into water policies, identifying ecological oases and managing groundwater to ensure species have access during droughts will be key, Rhode said.
As for rural communities, Lund proposed examining how and why urban and agricultural spaces have responded more effectively to drought: their missions are targeted; they have reliable sources of funding; they have organized authority and expertise; and they have a responsibility through voters, regulators and taxpayers.
“The state has a responsibility to ensure drinking water needs are protected and not ignored as a cost of business or pushed aside as something too difficult or inconvenient to address,” Massey said.
“Climate change is testing and overstepping our normal limits and flexibility,” she added. “The margin of error is getting narrower and narrower. That margin for error is already extremely slim, and what’s at stake is Californians’ access to a vital resource.
Los Angeles Times