On Monday morning, the quiet auxiliary parking lot at Descanso Gardens in La Cañada Flintridge turned into a construction zone, as crews started carving out space for a massive underground stormwater capture system. It is the first visible piece of a larger plan that will also restore the garden’s lake and build a three-acre Nature Discovery Garden for kids. Garden leaders say the project is meant to shrink irrigation demand and create a dedicated water reserve that can help firefighters if the hillsides ever light up.
The system is designed to catch runoff from an estimated 256-acre watershed, clean it up, and store it for reuse. Garden materials describe an underground cistern of roughly 1.5 million gallons and an annual capture capacity that the garden estimates could reach about 21 million gallons, according to Descanso Gardens. State environmental filings refer to the Winery Canyon Channel effort as a project that diverts stormwater to a 4.5-acre-foot cistern to offset potable irrigation needs, per CEQAnet.
A backup supply for firefighters
One explicit goal sits well beyond the garden fence line: wildfire readiness. By banking stormwater beneath the property, Descanso aims to keep an on-site reserve available for firefighting and emergency use. "Our commitment to environmental stewardship and conservation has never been stronger," Descanso Gardens CEO Juliann Rooke said in a statement to ABC7 Los Angeles. Garden officials say that stored water will be accessible to fire crews as part of the site’s emergency response planning.
Restoring the lake and a Nature Discovery Garden
The water project is just one piece of a broader overhaul. The plan calls for restoring the lake to rebuild wetland habitat, installing accessible boardwalks, and upgrading circulation systems to boost water quality and biodiversity. Nearby, a three-acre Nature Discovery Garden is slated to feature water play, a sensory garden, and a learning pavilion geared toward children and school groups, according to master-plan materials from Descanso Gardens.
Funding and local support
Money for the work is coming from a blend of grants, public agencies, and private fundraising, with ties to county flood-control and state conservation programs. Project paperwork from the Safe Clean Water Program shows the Descanso Gardens Foundation requested additional funding to keep construction on schedule. Local coverage lists support from Los Angeles County flood control and parks agencies, the California Wildlife Conservation Board, and the California Department of Parks and Recreation, according to MyNewsLA.
Why this matters
Projects like Descanso’s are part of a larger California shift toward catching water where it falls and using it locally, especially as the state ping-pongs between drought and drenching storms. State reporting on long-term water strategies notes that stormwater capture and reuse are increasingly paired with recycling and other tools to cut dependence on imported supplies and shore up communities against shortages, according to CalMatters.
Construction kicked off this week in the auxiliary parking lot, and garden leaders and county partners say the work is expected to wrap up in late 2027, according to reporting from ABC7 Los Angeles. When it is all done, visitors will get new access and education areas aboveground, while out of sight below their feet, the upgraded infrastructure is meant to lower irrigation costs and give regional fire crews one more option when things get hot.
