Every time it rains, even just half an inch, Los Angeles lets billions of gallons of water flow into storm drains. KPCC's Molly Peterson reports that people are employing new twists on old technologies to hold onto some of that bounty during a drought.
Molly Peterson: A big man with curly salt-and-pepper hair pulls on a yellow slicker and rubber boots. The skies are clear, but Jim Hardie is getting close to some rain.
Jim Hardie: We've got a whole 216,000 gallons of rainfall right beneath us here. [bucket clanking] So shall I go get some?
Peterson: Hardie directs park operations for TreePeople at Coldwater Canyon Park. That means he's often the one who climbs down into the cistern – a lined, 70-foot wide tank the group recently built below ground.
A metal pole gives Hardie leverage to pull a heavy lid off the access tube – a hole next to a wide, flat sandy area where kids play in dry times. In wet times, rainfall collects in the sand.
Hardie: All the water is filtered as it goes into the cistern through fabric filters, whether it's rain off our conference center roof, which is one main point, and then the parking grove is the other big point of collection, and all those drains and all those catchment areas have a fabric filter that gives it a filtration.
Peterson: You can see to the bottom in a pail of water Hardie's brought up – no sediment.
Hardie: It's nice and clear, no awful smell or anything like that, it's just a wonderful thing. It works.
Peterson: For more than a decade, TreePeople founder Andy Lipkis has been telling people it works. It's why his group pushed to build this cistern.
Andy Lipkis: This filled right when the city announced its new water restrictions, and the fact that we have a full cistern means that this entire park landscape that you see here will be watered exclusively by this. We've just gone off the grid.
Peterson: Los Angeles imports up to 85 percent of its water. Lipkis wants to cut that in half. Tree People's cistern is one way he'd like to show others how to do it.
Lipkis: Everybody enters the Lakretz watershed garden – and what we have right here [sound of water trickling] is the Los Angeles river – the past.
Peterson: Next to the cistern's access tube is a model of the L.A. River system – its miniature river tumbles over a rocky bed.
The water's fate splits at the urban outskirts – some falls straight into a pool – the symbolic ocean. When it reaches the model city, the water splits again.
Lipkis: We've entered a beautiful circle divided exactly in half with two identical neighborhoods. One is today – you see a paved road, asphalt, painted stripes. Curb, driveway, house, typical garden with sprinklers. Rosebushes.
Peterson: The roof of this model-sized house – and the concrete around it – bounce water into a small storm drain.
Water picks up trash and dirt on the hard surface – the ocean gets cloudy.
Lipkis: It's divided in half. On the flip side is another identical home, the exact same neighborhood, the exact same setup, but retrofitted. Restored.
Peterson: Lipkis says that model house has a mini-cistern – a rain barrel made of hard plastic, like a trash can. Simulated rainfall never hits the concrete streets. Park manager Hardie saw this contrast in real life during the last storm.
Hardie: What was so interesting during the rain was to stand at our entrance, and stand there, with no water flowing out of our parking lot, but water was gushing down Coldwater, you know, tumbling rocks and mud down Coldwater.
Peterson: TreePeople's project is a limited test. Right now L.A.'s building code makes it hard for homeowners to store rainfall on their property. The rules dictate that building downspouts must send water to the street.
Lipkis: The law requires you by code to throw that water away. We would have been creating a flood on Coldwater Canyon just throwing all that water away.
Peterson: The City of L.A.'s public works program is devising a pilot project for some houses to install rain barrels and roof downspouts that divert to water yards. California's long budget impasse froze the grant money for the project. TreePeople's Andy Lipkis considers every rainstorm a lost opportunity.