Rain catchment: An idea that truly holds water

Turn on the tap and water comes out. It’s a fundamental expectation of American life.

But aquatic ecologist Steve Lee is concerned that abundant water may not always be part of the Sonoma Valley story. “We have issues all around this watershed with groundwater depletion, and it shows up as diminished streamflow,” he said. “Creeks have been getting lower and lower, and creeks are the connection to underground water. That’s where the aquifer is visible.”

Lee thinks about water in ways that most people don’t. He thinks about water a lot. He studied water ecology at both UC Santa Cruz and UCLA, and is now the senior scientist and research program manager for Sonoma Ecology Center. Keeping track of the Valley’s water is Steve Lee’s full-time job.

But he is also a lifelong resident of Glen Ellen, still living on the same 5-acre slope where he grew up. Which is why, when he rebuilt his parent’s original home in 2013, he did it with water catchment at the center of his plans.

“An inch of water on a 1,000 square foot roof allows you to harvest 600 gallons of water. In a normal year with 30 inches of rain, that’s 18,000 gallons,” Lee said. “People don’t realize how much water we have landing on our roofs and driveways, contributing to flooding in wintertime.”

So Lee’s rebuilt home was designed to capture the runoff, and store it in a series of 5,000-gallon gravity-fed tanks. He’s got 11 of them scattered across his property, harvesting water from the house, barn and pool.

Lee’s plan for greater water independence predates the remodel of the main house, even. When he built a barn for the family’s livestock in 2009, its roofline was aligned with his water catchment plans, too.

“We live in an area where the wells are terrible. They’re getting worse and worse, and drying out,” Lee said. He’d already been forced to dig three by the time he rebuilt, and the only good option remaining was very near the creek. Lee didn’t feel right about tapping a public source for his private use, or worse, draining the habitat needed by local steelhead.

Old-timers remember when Sonoma Creek was abundant, rolling past their homes like free money. “Those houses along the creek, all of them had a pump house. That was how everybody did it,” Lee said. It was an old-fashioned solution to an everyday challenge, pulling water from the creek for non-potable use. People watered their lawns and livestock that way, pulling it up and over the banks with primitive pumps.

The practice remains legal, but is frowned on by ecologists as it depletes the water table modern life requires us to share. “Water rights laws are very deep and controversial. They’re a touchy subject in California,” Lee said. “Riparian rights are tied to property rights, so there’s a law that allows you to pull water from the creek. You can pull water out, but you cannot store it. You have to use that creek water right away.”

Lee’s catchment system, on the other hand, allows him to store nearly 60,000 gallons of water to use whenever he wants. When he completes installation of the system this fall and winter rains begin filling the tanks, he’ll use the water to grow most of the vegetables his family sells at farmers markets around town, and to water his orchards and livestock.

The tanks are 15 feet tall and eight-and-a-half feet across, connected by nearly 2,000 feet of mostly underground PVC pipe. The gutters and downspouts on the buildings are channeled into catch basins, which drain into a four-inch pipe heading downhill. At the base of the hill, the water finds its way over a 13-foot rise and into a tank connected to other tanks which fill collectively, as a unit. “It’s all gravity-fed pressure. The filling is passive,” Lee said.

With five acres of land on which to arrange his 11 tanks, Lee had good options for controlling the aesthetic. Still, some of the tanks are visible from the house, a fact that bothers Lee not at all. “When I see these tanks, it makes me happy. I don’t see them as an eyesore,” he said. “We all need to start seeing these things as things of beauty. I see these tanks and feel proud.”

Rainwater harvesting is legal in all 50 states on a continuum that ranges from “encouraged” to “highly regulated.” The California Rainwater Capture Act of 2012 allows private, commercial and government landowners to install, maintain and operate rainwater capture systems.

As California has grown and developed, the amount of stormwater flowing off buildings, parking lots, roads and other impervious surfaces into streams, flood channels and storm sewers has increased -- reducing the amount of water allowed to infiltrate into groundwater aquifers and increasing the pollution flowing into oceans and other surface waters. At the same time, recurring droughts and water shortages have made local water supply augmentation and conservation a priority.

As the climate warms, less of California’s water is predicted to fall as snow in the mountains, but rather as rain in other parts of the state. This shift is expected to have a profound effect on California’s hydrological cycle, with less water captured in the state’s reservoir system, which was structured to capture snowmelt.

The evolving scenario has become a sort of a perfect (rainless) storm, and with the average family of four using more than 400 gallons of water per day — and those living on country properties using far more — it’s a problem of increasing urgency, according to Lee.

The Ecology Center is currently seeking landowners in the Upper Nathanson Creek Watershed — North and Northeast of Sonoma — interested in exploring a variety of water storage and water diversion projects. From swales, or other topographic alterations to allow water diversion, to forecast-informed pond management projects, to stormwater detention and rainwater storage projects like Steve Lee’s, the center is offering free consultations for citizens interested in rethinking water flow on their properties, and contributing to the county push to “slow it, spread it, sink it, store it!”

“We need to be better at providing our own water security,” Lee said.

Contact Kate at kate.williams@sonomanews.com