Descanso Gardens Lake & Stream Promenade Concept Development

Project Description

Located in La Cañada Flintridge, a city only 20 miles from downtown Los Angeles but bordered by the San Gabriel Mountains, Angeles National Forest, and the San Rafael Hills, the 160-acre Descanso Gardens provides refuge for people and wildlife alike. Situated at the base of several canyons, the 100-year-old site includes two water features–a small recirculating stream and a two-acre lake–fed partially by stormwater from the adjacent hillsides and from a spring located high up in the mountains.

The Gardens wanted to improve the water quality, habitat value, and aesthetics of the lake while also addressing its aging liner and ensuring wise water use. Partnering with The Portico Group, Biohabitats crafted a concept to help the Gardens achieve these goals while also enhancing the site’s impact on both its visitors and regional ecology.

The team began by assessing the site’s water infrastructure, with particular consideration to the Gardens’ context within its local watershed. Upon discovering that upstream from the site, natural springs cascade through a thriving riparian zone, the team approached the project with the intent to minimize draw from the springs.

The team then created a concept to link the hillside arroyos, lake, and winding waterway in an interconnected system through which water is continually filtered and recycled with the help of upgraded recirculation pumps and ecological features like living shorelines, biofiltration wetlands, and check dams to better manage incoming sediment. These features not only remove sediment and nutrients from the water, but add habitat, diversity, beauty, and new visitor experiences to the Gardens' landscape.

By reducing the need to draw water from the canyon springs, the concept helps the Gardens protect upstream ecology, reduce its water footprint, and enhance its resilience to the uncertainty posed by climate change and earthquakes.