How much water did Hilary add to the Salton Sea? 'It’s not nothing, but not that much'
In the days leading up to Tropical Storm Hilary, some on social media speculated whether the incoming deluge could help fill the shrinking Salton Sea.
After all, the storm was forecasted to bring more than a year’s worth of rain to the desert over the span of two days, and earlier this year, California’s historically wet winter brought back the long-dry Tulare Lake in the San Joaquin Valley.
But those familiar with the Salton Sea say anyone hoping that a large storm could save California’s largest lake shouldn’t hold their breath, and should realize that a storm large enough to make a difference for the sea’s declining water level also would bring devastating impacts to the surrounding region.
“The reality is this doesn’t really have a lot of positive impacts for the sea. People will see a lot of water flowing into the sea and expect the water levels to rise significantly, but that’s not the case,” said Frank Ruiz, Salton Sea program director for Audubon California.
A gauge maintained by the U.S. Geological Survey shows the Salton Sea’s water level rising by a little over 2 inches following the storm.
“It’s not nothing, but not that much. It’s similar to the order of about 35,000 acre-feet, which is not a bad amount of water, but given the large size of the Salton Sea it’s not all that much,” said Michael Cohen, a senior researcher with the Pacific Institute who has spent decades focused on the Colorado River basin and the Salton Sea.
Annual evaporation from the Salton Sea is approximately 1.3 million acre-feet of water per year, according to the Salton Sea Authority. The Salton Sea’s surface elevation has dropped by more than 11 feet since 2003, when an agreement led to the diversion of significant amounts of Colorado River water from rural Imperial County to urban areas, resulting in less agricultural runoff into the sea. The resulting receding shoreline has left thousands of acres of exposed dusty and toxic lakebed, or “playa,” surrounding the sea, contributing to the region’s poor air quality and high rates of asthma.
“With climate change and high temperatures, we expect even more drastic evaporation on a regular basis. The influx right now is about 700,000 to 900,00 acre-feet of water per year, but with the evaporation rates at about 1.2 million, that has a major impact in terms of water loss,” said Ruiz.
The shallow Salton Sea is California’s largest lake by surface area, which means any rainfall and runoff from storms is spread out across a vast area, in addition to competing with the sea’s evaporation rates.
In 1976, Tropical Storm Kathleen caused the Salton Sea to rise by six inches during the two-day storm. But that storm also caused vast destruction throughout the desert, destroying the Imperial Valley community of Ocotillo and causing the deaths of six people.
“A storm that could add a considerable amount of water to the Salton Sea, maybe even a foot from a major storm, would have huge devastating impacts and costs in terms of people and property. Even with a storm that raises it a foot, the Salton Sea is down 11 feet, and I wouldn’t wish eleven hurricanes on the valley to restore the Salton Sea,” Cohen said.
Instead, fixing the Salton Sea will require a feat of engineering. The U.S. Army Corps of Engineers is currently in the midst of a three-year feasibility study focused on evaluating which of more than a dozen possible large-scale engineered solutions are feasible. Those potential solutions were laid out in a draft long-range plan released by state agencies last December, and range from building and filling a narrow “perimeter lake” around the edge of the exposed lakeshore, splitting the lake in two, building desalination plants, or importing water from Mexico’s Sea of Cortez, among other proposals.
This article originally appeared on Palm Springs Desert Sun: Salton Sea: Did Tropical Storm Hilary help with water levels?
