LOS ANGELES — Today, Councilmember Eunisses Hernandez, alongside City leaders and community partners, marked Earth Day with a press conference to unveil the designs for the MacArthur Lake Stormwater Capture Project—a $40 million investment that will convert the lake into a system that captures, treats, and reuses local stormwater.
Funded through Measure W, the project will shift MacArthur Lake away from reliance on imported potable water and instead use a flow-through system that diverts stormwater runoff from the existing storm drain system, treats it, and stores it in the lake.
In addition to water infrastructure, the project will enhance MacArthur Park with new community-focused improvements, including a cascading water feature, shaded seating areas, new trees and native landscaping, improved walking paths, a pedestrian bridge, and educational signage highlighting the benefits of stormwater capture. Construction is anticipated to begin with a groundbreaking in Fall 2026.
“This is a major investment in the long-term health of the park, bringing new amenities for the community, and building on our work to address decades of underinvestment in a park that serves as the front and backyard for thousands of families,” said Councilmember Hernandez. “This project is a direct result of voter-approved Measure W, driven by Angelenos who called for solutions to improve water quality, strengthen our local water supply, and invest in green infrastructure in communities that need it most. I’m grateful for the collaboration between the City and County to deliver this work and bring real, lasting improvements to the Westlake community.”
Project Details and Impact
Once complete, the MacArthur Lake Stormwater Capture Project will capture and treat approximately 244 acre-feet of stormwater each year, reducing harmful contaminants, including sediment and metals, improving water quality, and protecting downstream ecosystems.
The system will also offset the use of imported potable water, saving approximately 9 million gallons of water annually, while strengthening Los Angeles’ local water supply. These improvements come as the City works to reduce reliance on imported water, prepare for climate impacts, and invest in long-term sustainability.
“The MacArthur Lake Stormwater Capture Project has the potential to be one of the most unique and impactful in the Measure W Safe, Clean Water Program,” said Traci Minamide, Interim General Manager and Executive Director of LASAN. “Once constructed, this project will improve water quality in the Ballona Creek Watershed and will save approximately nine million gallons of water, the equivalent of nearly 14 Olympic-size swimming pools, per year.”
“When Los Angeles County voters approved Measure W in 2018, they envisioned a way forward for the city and the county to create stormwater initiatives that improve water quality, increase local water supply, and provide community benefits,” said Alfred Mata, Interim City Engineer and head of the Bureau of Engineering. “Today, in honor of Earth Day, we are bringing one of these projects to life, making our water cleaner, our City’s water supply more sustainable, and bringing more nature to the park for area residents and their families to enjoy.”
“As we commemorate Earth Day with the unveiling of the designs for the MacArthur Lake Stormwater Capture Project, I want to first acknowledge Councilmember Eunisses Hernandez’s leadership and commitment in working with us to revitalize this jewel in the heart of our city," said Jimmy Kim, General Manager of the City of Los Angeles Recreation and Parks Department. "Her dedication to prioritizing the needs of MacArthur Park helps to enhance the park’s ecosystem and ensures that it remains safe and accessible for families and the community to enjoy."
This project builds on more than $27 million in prior investments led by Councilmember Hernandez to revitalize the park, including clean teams, harm reduction and overdose response services, violence prevention, solar lighting, landscaping, family-friendly programming, and an upcoming Health Hub.
“Over the last three years, we’ve secured a historic $27 million in the Westlake–MacArthur Park area to advance coordinated public health and safety efforts that have already saved lives, removed tens of thousands of hazardous items, and kept dozens of residents housed, while also investing in infrastructure like solar lighting, restoring and improving recreational areas, and clearing thousands of bags of trash,” Councilmember Hernandez continued. “This is what it looks like to build a coordinated, multi-pronged approach that meets people where they are, improves public spaces, and delivers real, lasting investment to MacArthur Park for the people who live, work, and play in the area.”
Media assets, including renderings of the stormwater capture project, photos, and b-roll, are available here.