With the western United States stuck in a 22-year drought, some residents of Tucson, Arizona have a secret to surviving in the desert.

They collect rainwater.

Evaristo Ramirez Barajas is one of them. Despite the sweltering desert heat, her garden is shaded with mesquite, creosote and cacti.

“It hasn’t been a good season for Tucson,” Barajas said. “We struggled a lot with this monsoon, but even [with] that, we still have water.

Bajaras has installed a 1,000 gallon rainwater tank in her garden, and her plants are getting a boost from the system. When it rains, water flows from its roof into a gutter that leads to the reservoir. It uses a hose attached to the bottom to irrigate the trees.

The system is also a way for Barajas to earn money. He is part of a small business called Tucson Rainwater Harvesting Co-op. Barajas and other members have been installing reservoirs for a few years now and the current drought has been good for business.

The city of Tucson also helped. The water department offers a discount for rainwater collectors. A resident who purchases a 1,000 gallon tank will receive a check for $1,000.

“I think the potential is huge,” says James MacAdam of the city’s water department. “I think of parts of Australia where 15 years ago rainwater harvesting was illegal. And then they had a massive drought and now it’s mandatory in a lot of cities.

In Tuscon, 90% of the city’s water comes from the Colorado River. Harvested rainwater is literally a drop in the bucket.

Evaristo Barajas of the Tucson Rainwater Harvesting Co-op shows off his outdoor shower. It uses water collected from the rain. (Peter O’Dowd/ Here & Now) But MacAdam says rain barrel owners save an average of about a month’s worth of city water each year. It won’t solve a water crisis, but MacAdam says that as the climate gets hotter and drier, rain harvesting will play a bigger role “because it’s one of our most great untapped sources of water”.

With each month of a 22-year drought, the need becomes more urgent. In June, federal officials warned states that use the Colorado River to take the reduction seriously. The Arizona legislature has also just approved spending a billion dollars to find new sources of water. Part of the money will go to support the Rains Harvest, which Brad Lancaster spends his life thinking about.

In the mid-1990s, Lancaster and his family joined a group of neighbors who wanted to bring the neighborhood to life with more trees. Summer monsoon rains would release torrents of water that would flow “like an ephemeral stream” down the street, Lancaster says.

Neighbors tried to divert the deluge from the street, even going so far as to cut the curb so rainwater could run off the trees.

Now, after years of work, the entire street of Lancaster is covered in mature desert shade trees. But Lancaster didn’t stop there. Over the course of a year, 95% of Lancaster’s water is captured by rain.

“We haven’t had substantial rain since late December,” Lancaster said. “It’s July and I’m still drinking, cooking and bathing with rainwater. I think it’s pretty good!”

But Lancaster says with severe shortages on the Colorado River, it’s frustrating to see no one taking action.

“While the Lake Mead and Lake Powell reservoirs are shrinking very rapidly, people are still bickering over who should conserve water and/or they are trying to get water from somewhere else,” says Lancaster.

Lancaster says the solution could be to use rainwater, which is already available, and make rainwater a primary water source, using groundwater or water from the Colorado River, as a reserve.

“If you start now when you have all the options on the table, you have time to learn,” he says. “It gets easier.”

However, rain collection is still labor intensive and tanks cost money. Eravisto Barajas of the Tucson Co-op says installing a large tank costs about $1,500.

Of the 40 million people who depend on the Colorado River, not all would choose to live like Lancaster and Barajas. But they are among those who thrive in the desert, unconnected with the fate of a rough river.

Peter O’Dowd produced and edited this broadcast interview with Ciku Theuri. Jeannette Muhammad adapted it for the web.