How California's Droughts Lead to Other Disasters
zNbT8ROPmK4 • 2021-06-29
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Kind: captions Language: en - [Narrator] The news in 2020 said it all. - [Newscaster] August Complex fire has become the largest fire in state history. - [Narrator] A record setting year for wildfires in California. They burned over 4 million acres, an area larger than the state of Connecticut. But wildfires don't just happen, they need fuel. And the thing that's been creating a lot of fuel for fires lately is drought. (gentle music) Drought is back. Already, across the Western United States, extreme drought conditions cover more land than any point in the last 20 years. Which means the 2021 wildfire season could be the worst yet. Drought, simply put, is a lack of water, usually caused by little or no rainfall, but rain isn't the only source of water for California's reservoirs. - In California people rely a lot on snow. - [Narrator] Melting snow from the Sierra Nevada mountains provides a third of California's agricultural and residential water supply. - You may have average rainfall, but way below average snow. If you look at rainfall, you may not see any drought signal, but if you bring snow into the problem, then you may practically end up in a drought situation in California. - [Narrator] That's what happened this spring. The snowpack was so small, reservoirs barely received water from melting snow and any remaining runoff was absorbed into a parched ground. But dwindling water supply isn't the only problem facing Californians. - Drought interacts with many other hazards between 2012 and 2016 we experienced a prolonged and extreme drought in California. The drought ended with a series of extreme precipitation in winter of 2017. (thunder rumbles) - [Narrator] Extreme drought, then lots and lots of rain all at once, resulting in a rapid plant growth. - Then the summit of 2017 was very hot and dry. This dryness created perfect situation for what dried the vegetation, the shrubs and grass. - [Narrator] The dried out vegetation became fuel to feed, at that time, the largest fire on record, the Thomas Fire in Southern California, which forced over 100,000 people to evacuate their homes. Then a month later, another disaster ricocheted across the news, rain. Rain's good for droughts, but when it washed over the burned area, it caused flooding and landslides killing 23 people near Santa Barbara. In California, heat waves, drought, wildfires, and flooding operate together, creating a deadly combination. Then there's climate change. - In a warming climate, we expect faster snow melt when snow falls on a burned environment there's no canopy to protect it against solar radiation, it melts faster. Faster snow melt, again, increases the chance of flooding in spring and increases the chance of drought later in summer. - [Narrator] This cycle doesn't just increase the number of deadly wildfires, drought is also reducing the amount of drinking water available in the region. So what can we do about this? Engineers are working on new ways and new sources for providing enough safe water to drink and use. - I see these drought periods as an opportunity, actually, to rethink the way we use our resources. - [Narrator] One solution might be found in our toilet. By transforming waste water, into drinking water, something called direct potable reuse. It might sound gross. - There's kind of that yuck factor. People think, oh, I don't wanna be drinking my neighbor's toilet water, right? And that's not true. - [Narrator] And that's because that wastewater, from your neighbor's toilet or your kitchen sink is sent to a treatment plant where contaminants are removed. Then the water's pushed through filters that allow only water molecules through, no impurities. - We can recover about 70 to 80% of the water that comes into our system. - [Narrator] The question is, can we clean up that remaining 20 to 30%? - One of the things that we're looking at are some other advanced technologies. - [Narrator] Kerri Hickenbottom's team is using solar power to remove those contaminants by evaporating the water, leaving behind salts and other gunk. The water vapor can then be recondensed into a liquid. - We're able to take the energy from the sun and directly use that to produce a very high quality source of water. - [Narrator] This process can recover almost all of the remaining wastewater. It's a promising solution, especially in remote locations, like among Native American Nations. - And we have a lot of tribal communities such as the Navajo Nation in Arizona, that doesn't necessarily have access to high quality water. - [Narrator] With Kerri's purification system, these communities could sustainably maintain their water supply. And besides high-tech solutions like this one, there's also low tech things that we can all do, like just using less water. In fact, increased media coverage of the California drought last year actually changed people's behavior. - Every one of these droughts have led into change in the way we do things. And I think this is a great reminder to us that everything that we have around us, we should not take it for granted. I look at droughts as an opportunity to learn, adjust, and adapt and be better at the way we use our resources.
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