After a torrential downpour, most post-storm damages are impossible to miss: submerged cars, houses torn in half by fallen trees, debris floating through the streets. But in California, extreme weather is also mixing up a soup of rain and disease.

Climate-fueled outbreaks: In Southern California, an atmospheric river unleashed more than a foot of rain in parts of the region at the start of February. These types of storms also ravaged the state last year, following a decades-long period of drought. The climate-fueled cycle of rain and drought is driving an uptick in a fungal disease known as coccidioidomycosis, or Valley fever, reported Grist last week. As it rains, the fungi proliferates in the soil, and when it dries out, spores are kicked up from the ground and into people’s noses or throats, potentially leading to pneumonia-like symptoms of cough and fever. 

Scientists sounded the alarm bells for rising Valley fever cases due to changing environmental conditions in 2022, but the data has since become even more stark. There were more than 9,280 new cases of Valley fever with onset dates in 2023, which is the highest number ever recorded in this region by the California Department of Public Health. Around 200 people in the United States die from severe cases of this respiratory disease every year. 

Also mixed into the post-storm soup of ocean water, fungi spores, rain and debris in California? Millions of gallons of untreated sewage. This bacteria-ridden wastewater poses a severe public health threat, particularly for those closest to the California-Tijuana border, which I wrote about earlier in February. Two local San Diego doctors I spoke with told me a particularly unsettling statistic: After Tropical Storm Hilary slammed into Southern California in August 2023, their practice saw a 560 percent increase in diarrheal illness cases. 

A report released last week by scientists at San Diego State University further underscored the severity of this public health threat, adding that wastewater can also carry toxic chemicals alongside bacteria. California government representatives are currently advocating for $310 million in federal funds to refurbish the state’s dilapidated sewage treatment plant at the border — an increasingly urgent request as the state currently faces another round of storms fueled by the atmospheric rivers. 

Disease, water and war: Unfortunately, this kind of post-storm sewage overflow can be seen well beyond California. In November, wastewater flowed through the streets of Gaza amid the Israel-Hamas War as storms pummeled the region and sanitation services stopped operating. With a short supply of clean drinking water, civilian camps were ravaged by disease, and cases of diarrhea in children under five increased from 48,000 to 71,000 in just one week starting Dec. 17, according to UNICEF.

“Our whole family has diarrhea that seems to be caused by the water we drink, or the cold weather,” Mahmoud Aziz, a 36-year-old who fled to Rafah, told the Washington Post on Dec. 13.  “We leave the windows open because of the bombing; we are afraid of the glass if there is a bombing.”

On Feb. 12, Israeli airstrikes killed more than 100 people in Rafah. 

Halting the Run on Dwindling Groundwater

A judge in Montana recently ruled in favor of landowners and ranchers fighting against a housing development project near Helena that could have put further stress on steadily declining groundwater reserves. 

Public defiance: Initially, the state and county governments had signed off on a developer’s plans to build 39 homes that would pull their water from wells, a project that was challenged by local residents in central Montana. But Broadwater County District Court Judge Michael McMahon found that the county commission and state’s Department of Natural Resources (DNRC) had conducted an “abjectly deficient” environmental assessment for the housing construction. 

His 85-page order stated that the offices’ approval of the project displayed “hostility” toward a previous court ruling that requires the government to consider the potential harms to the environment and groundwater before allowing for development. 

“It should give DNRC pause that citizens with seemingly no legal training appear to have a better grasp of the exempt well limits than DNRC, the agency charged with administering the Water Use Act,” McMahon wrote.  

While the coalition fighting this project celebrated the ruling, developers worried about its long-term implications. 

“Where are we going to house citizens of Montana?” Eugene Graf, president of the Montana Building Industry Association, told The New York Times, adding that he hopes state lawmakers revise the law. 

Shutting off the tap: If upheld, the “landmark” decision has the potential to curtail many new development projects in rural Montana, reported the Montana Free Press. The ruling isn’t the first of its kind: At the end of January, the Nevada Supreme Court unanimously ruled that the state can restrict new groundwater pumping if it will negatively affect other users and wildlife, while Arizona’s governor is pushing for broad reforms and the creation of groundwater-minded laws across the state, as my colleague Wyatt Myskow reported in December. 

These actions come amid a widespread reckoning against rampant groundwater usage. Last August, a New York Times investigation revealed that much of the U.S. is facing drastic declines in their aquifers as climate-fueled droughts force residents to rely more on groundwater supplies for water than rain or snowpack. More recently, a study showed that this pattern can be seen globally, with aquifers shrinking around the world. 

But not all hope is lost. 

“We also find cases where declining groundwater trends have been reversed following clever interventions,” Scott Jasechko, a water resources expert at the University of California, Santa Barbara who co-led the study, told my colleague Liza Gross. 

For example, Tucson, Arizona, reversed groundwater declines in some areas by constructing “leaky ponds,” which seeped much-needed water into aquifers, the study’s authors wrote in The Conversation. 

More Top Climate News

Hawaii is Considering a ‘Climate Tax’ for Tourists: Gov. Josh Green is spearheading a push to charge island visitors with a $25 tax to help offset the environmental impact of tourism, Jeremy Yurow reports for USA Today. The proposed bill would allocate the money toward initiatives to restore coral reefs, build greener infrastructure and implement measures to prevent wildfires like the ones that tore through Lahaina on Maui in August.

A New Satellite Tool Will Help Users Map Methane Leaks: Google recently partnered with the nonprofit Environmental Defense Fund to launch an AI-based satellite tool that could offer the most detailed look yet of global methane emissions from oil and gas operations. This could help governments pinpoint and plug the “types of machinery that contribute most to methane leaks,” Yael Maguire, who leads geo-sustainability efforts at Google, told James O’Donnell for MIT Technology Review. 

An update following Friday’s newsletter … which covered the intense debate between Maine’s lobster industry and conservationists after an endangered North Atlantic right whale washed ashore in Martha’s Vineyard with lobster gear entangling its tail: Another dead North Atlantic right whale was spotted last week off the coast of Savannah, Georgia, this time with injuries consistent with a vessel strike. Boat collisions are one of the other leading killers of this marine giant alongside gear entanglements, and I covered a deep-dive of this issue in October if you’d like to learn more.