Collaboration Creates Multi-Beneficial Bioswale Project by ACWA Staff Jan 16, 2026 Newsletters Photo courtesy of CVWD A broad collaboration between a Region 8 ACWA member agency and conservation groups overcame regulatory barriers to create a stormwater capture project — a bioswale that captures stormwater, recharges a local aquifer and benefits wildlife and local education all at the same time. Completed in late 2024, the bioswale came about through a partnership among the Crescenta Valley Water District (CVWD), Los Angeles County Flood Control District, Arroyos & Foothills Conservancy and its affiliated Friends of Rosemont Preserve advisory committee. The project itself is simple: a 3-foot-deep, 600-square-foot depression landscaped with plants native to the preserve. It works by slowing and capturing stormwater flowing out of a canyon watershed in the Rosemont Preserve, part of the western foothills of the Angeles National Forest. Stormwater absorbs into the naturally porous soils and recharges an aquifer that provides roughly half of the Crescenta Valley’s drinking water. The project represents out-of-box thinking to overcome all-too-common barriers to such projects such as thorny water rights, numerous permits, costly construction, and other costs and delays. It wasn’t necessarily easy, said CVWD General Manager James Lee. “Ultimately, we were just trying to dig a hole in the ground,” Lee said. “We had completed a feasibility study, developed designs, pivoted projects to circumvent water rights issues, applied for and received a permit — think we were done — then learn that we’d need still other permits, one of which would take several more years,” Lee said. “At a certain point, we looked at each other and determined that we would somehow find a way to complete the common-sense project within reasonable time and cost.” Partners were identified, and the partnership generated momentum that pushed past regulatory and challenges. The collaborative effort secured support from nonprofits and other local governments, namely the city of Glendale and communities such as La Crescenta, along with Los Angeles County. Without that buy-in, the bioswale project could have foundered during a years-long bureaucratic process. Once all the permits and approvals were in place, the actual work creating the bioswale took place over a weekend through the work of volunteers. CVWD provided a couple of backhoes, turning the work into a staff training opportunity on heavy equipment operation. The bioswale is now part of enhancements to the nature preserve that draw school field trips from across the region and is joined by other projects, including a gate to a trail designed by local tribe members. Heavy rains dousing Southern California in December put the project to the test. “It worked great, just as designed, and it’s been exciting to watch,” said Frank Colcord, a volunteer and Co-Chair at the Friends of Rosemont Preserve and a Board Director at nearby Foothill Municipal Water District. It also adds wildlife habitat, serving as a watering hole for deer, mountain lions and fox. “Pretty much everything that lives in Southern California comes through here,” Colcord said, about its benefits to local wildlife species. As for enhancing water supplies, the bioswale might add an extra five to 15-acre-feet of aquifer recharge a year. But that’s not really the point, Lee said. “Is that a huge amount of water? Absolutely not,” Lee said. “It’s definitely a symbolic project. We’re an Anytown USA Water District, and the primary value of this project is to demonstrate to ourselves and others that we can pursue timely and real results with imagination and collaborative work. It’s a vision that produced a success, and it all comes down to making friends and forming partnerships.” Crescenta Valley has subsequently planned for similar short and longer-term projects, including through DROPS (Data-Driven Resource Optimization and Planning System), a collaboration between Foothill Municipal Water District, Glendale Water & Power, Pasadena Water & Power, the California Data Collaborative and Crescenta Valley. It is an initiative that prioritizes future stormwater projects using satellite data to identify more pervious soils and is funded by Metropolitan Water District of Southern California’s Future Supply Actions grant.
