What we do:

The Problem:

San Francisco’s west side sits over a 45 square mile water reservoir called the Westside Basin Aquifer. Historically, rainwater seeped through vast areas of sand dunes and collected over bedrock hundreds of feet below the surface before flowing laterally through the sand and escaping into the Pacific Ocean. As San Francisco has developed over the last hundred years, nearly all of the permeable sand that once fed the aquifer has been paved and built over.

As a result of urban development, impervious surfaces (roads, sidewalks, rooftops) disrupt the hydrological cycle. Water that falls on these surfaces in the city is treated as wastewater in our combined sewer system, overwhelming our treatment centers and disrupting natural infiltration. Each year, San Francisco discharges nearly 2 billion gallons of untreated, combined stormwater and raw sewage into San Francisco Bay and onto Ocean Beach.

A continued failure to be proper stewards of our local hydrological cycle will cause further ecosystem collapse in the the bay delta and maintain high wastewater treatment costs for San Francisco residents.

Our Solution:

Aquifer recharge through green infrastructure at both residential and commercial scales has the potential to bring the City of San Francisco into better relationship with the ecology and hydrology of our region, reduce costs for the PUC and residents, and build water source resilience.

Why:

  • less strain on our combined sewer system and fewer sewage overflows during storm events

  • rainwater that enters the aquifer can be pumped later as drinking water instead of being mixed with sewage and undergoing a costly treatment process

  • A healthy aquifer underneath San Francisco is a durable alternative source of water for years to come

How:

  • Take the rainwater that falls on our roofs and put it into the ground by installing rainwater catchment and natural infiltration systems

  • Bundle residential properties to at least .5 acres of total roof surface area and disconnect rainwater leaders from the sewer system at scale

  • collaborate with large property owners to secure funding and implement green infrastructure that prioritizes permeable surfaces.