A drought emergency was declared in two northern California counties by California Governor Gavin Newsom earlier this week. This has many wondering about the future impacts of the state’s new drought on California, but what many don’t realize is that the state is still reeling from the impacts of the last one.
NSPR’s Sarah Bohannon recently spoke with Jay Lund, professor of civil and environmental engineering and co-director of the Center for Watershed Sciences at UC Davis about the obvious — and not so obvious — impacts of the state’s current and past droughts.
Read the transcript
KEN DEVOL, HOST:
California Governor Gavin Newsom declared a drought emergency in Mendocino and Sonoma counties on Wednesday, and that emergency could soon extend to other counties. Right now, most of California is in a severe drought according to the U.S. Drought Monitor. NSPR’s Sarah Bohannon recently spoke with one water researcher to learn more about what heading into another multi-year drought could mean for the state.
SARAH BOHANNON, REPORTER:
When most people hear the word drought, they think about cities having to ration water or farmers needing to fallow crops. But Jay Lund professor of civil and environmental engineering and co-director of the Center for Watershed Sciences at UC Davis says the impacts of drought are even more far-reaching.
(SOUNDBITE OF JAY LUND) “Particularly with the warm droughts we’re seeing with climate warming, and the last drought in particular, a lot greater impacts to the forests. Past droughts have also had a lot of tree deaths, but this last drought we had more than 100 million trees die up in the forests of California.”
Lund says less rain is one factor for these tree deaths, but they’re mostly due to human-induced climate change that’s led to hotter temperatures, which are drying out moisture in the landscape at a fast pace. Lund says research shows that evapotranspiration – or the process of water being transferred from the soil and plants to the atmosphere – was responsible for about 25 percent of the water deficit during the last drought. He says dry landscapes and dead trees left behind have contributed significantly to the megafires California has seen over the past few years.
(SOUNDBITE OF JAY LUND) “To some degree, the drought impacts have been greatest since the last drought after the drought ended because of the wildfire impacts on property and public health were generally much greater than the drought impacts during the drought, and I expect we can see the same thing for this drought.”
Some of the traditional drought impacts Lund says we can expect to see this drought include lower groundwater levels. That’s especially true for rural areas, Lund says, as farmers will likely increase groundwater pumping to make up for surface water they don’t receive.
(SOUNDBITE OF JAY LUND) “And what this does is it leaves many wells going dry in the rural areas both for households and for small communities because the agricultural wells – the big production wells for agriculture – tend to be much deeper than household wells or small community wells.”
Lund says there are many other less obvious effects we’ll probably see with this drought: hydroelectricity generation will likely decrease; the Pacific Flyway – a corridor used by waterfowl to migrate up and down the state – could be affected; as well as the state’s fish.
(SOUNDBITE OF JAY LUND) “The native fish have been having quite a lot of troubles. Typically, they tend to decline during drought and then they recover somewhat after the drought. After the last drought, they didn’t recover very much so we still have some quite low numbers for winter run salmon and of course delta smelt.”
We’re in the second year of the state’s new drought, but Lund says water levels at Shasta Dam – which walls off the state’s largest reservoir – are already close to those in the third or fourth year of the state’s last drought.
(SOUNDBITE OF JAY LUND) “And that’s a problem because we rely on that large amount of storage to preserve cold water for the spawning salmon and the salmon eggs for the winter run salmon.”
Lund says Californians can expect all these issues to continue over the next few years and over the long-term. One of the reasons is that the Sierra snowpack that has traditionally supplied about 30 percent of the state’s water requirements is starting to melt earlier than normal. Lund says stream flows over the last 100 years show that one percent of the state’s spring water flows are now running off earlier, in the winter.
(SOUNDBITE OF JAY LUND) “We’re going to have to make some tradeoffs in terms of agriculture, urban and different environmental uses of water. These are always going to be difficult issues and we’ll just as a society, this is just an eternal problem that California will have.”
While the drought is not going away, Lund says there’s a lot the state can do to manage the problem. If steps aren’t taken, he says California could be facing a lot more damage to the ecosystem and possibly to public health.
For NSPR News, I’m Sarah Bohannon.
