The Salmon Protection and Watershed Network (SPAWN), with funding from the Marin Community Foundation, has launched its Stormwater Catchment & Water Conservation Initiative for Marin County residences and businesses.

The simple idea behind the program is to collect and store rainwater in the wet winter months and use it for irrigating gardens, lawns and landscaping in the dry spring and summer months.

SPAWN will use the $60,000 funds to educate, motivate and provide economic incentives to residents and businesses who want to participate and is currently actively signing participants up for the program.

“The program has multiple benefits for people, endangered salmon and the environment, and the timing is extraordinary, considering the Governor has announced a State-wide drought emergency,” said Paola Bouley, Conservation Program Director for SPAWN. She noted that the original proposal was drafted last year in the middle of a wet winter, but with drought on everyone’s mind, interest in the program is growing exponentially.

By using stored rainwater for irrigation, residents are conserving treated water for important human needs such as drinking and washing, which becomes an ever more critical resource during drought conditions. Onsite rainwater catchment systems also reduces energy use. Bouley noted that the energy needed to move water from reservoirs to treatment plants to households makes MMWD the largest user of electricity in the
County. “By reducing water use, we also help reduce our carbon footprint and fight global warming.”

Finally, she noted, “Capturing stormwater and reducing peak run-off from impermeable surfaces such as roofs also helps reduces downstream erosion of creekbanks and sedimentation of salmon spawning beds.” If the reasons weren’t enough, Bouley noted that having a onsite water storage on your property, carefully situated and with properly fitted valves, can also be a benefit to firefighters during an emergency, especially in the urban – wildland interface.

The focus on utilizing abundant stormwater runoff to meet part of our spring and summer irrigation needs is an important conservation measure that reduces the ever-growing
demand for water, which in Marin County outstrips local supply by more than 25% requiring imports from the Russian and Eel Rivers and fueling an MMWDproposal to build an expensive and energy-intensive desalination plant in San Francisco Bay. According to MMWD, currently 50% of the total water used in Marin during the summer is used solely for irrigating lawns and gardens.

In 2006, with funding help from the EPA and State Water Resources Control Board, SPAWN in partnership with the Lagunitas School built a demonstration roof stormwater harvesting project. In an average rainfall year, a 1,600 sq. Ft. lunch-shelter roof on the playground functions as an above ground well, capturing 30,000 gallons of pure rainwater that is then stored in a cistern and used for irrigating the students organic garden project. Left un-captured, the roof runoff would have drained onto a concrete pad and into a 10-inch stormdrain that emptied directly into Larsen Creek, a stream sensitive to erosion that is also home to endangered coho salmon.

The wild coho salmon and steelhead found in Marin represent the largest and 2nd largest respective remaining runs of these fish in Central California. Stormwater runoff from excessive impervious surfaces (roads, parking lots, thousands of roofs) erodes streambanks causing siltation of key spawning grounds and combined with loss of floodplain and riparian habitat, washes baby fish out to sea before they are ready to migrate.

“Reducing stormwater runoff not only helps offset impacts on our salmon and watersheds, but can also help decrease our dependence on unsustainable water imports from the Russian and Eel Rivers and relieve pressure on local supplies from behind dams
on Lagunitas and Nicasio Creeks, said Bouley. She added, “People are hungry for practical solutions to common sustainability issues. And with clean water supplies becoming ever more strained in California, roofwater harvesting is just one of the
additional tools that needs to be included in our conservation “toolbox.”

MORE INFO: On July 31 from 7-9PM at the Women’s Club in Fairfax, SPAWN and Sustainable Fairfax will announce their respective new programs to help landowners design and fund rainwater harvesting projects. Brock Dolman, Director of the WATER Institute at the Occidental Arts and Ecology Center, who was featured in the recent documentary the “11th Hour,” will also lead a presentation on water catchment. $5-10 donation requested.