Council to Mull Environmental Exemption for Brookside Stormwater Project

Pasadena City Council is scheduled Tuesday, Oct. 20, to consider approving the design concept for the Brookside Park Stormwater Capture Project and finding it categorically exempt from the California Environmental Quality Act, advancing plans for an underground runoff treatment system near the Rose Bowl.

The project would be installed beneath Parking Lot I at Brookside Park, 360 N. Arroyo Blvd., and is intended to reduce pollution entering the Arroyo Seco while replenishing groundwater supplies in the Raymond Basin.

According to the city’s Department of Public Works, the proposed facility would collect and treat stormwater and dry-weather runoff from approximately 1,166 acres in northwest Pasadena.

The design calls for an underground infiltration system with an 11-acre-foot capacity. Water diverted from the Seco Street Drain would undergo pretreatment before entering subsurface storage and infiltration facilities.

The city says the treatment process is intended to remove trash, sediment and other pollutants from runoff that would otherwise reach the Arroyo Seco, which flows downstream into the Los Angeles River.

Aboveground improvements described by Public Works include bioretention areas, vegetated bioswales, landscaping, increased tree canopy and improvements to the existing parking lot.

Environmental exemption before council

The Oct. 20 agenda recommends finding the project categorically exempt under five sections of the state’s environmental guidelines covering existing facilities, replacement or reconstruction, construction of small structures, minor alterations to land and infill development.

City staff also recommend finding that no unusual circumstances prevent applying those exemptions.

The environmental approach now before the council differs from the process outlined in an earlier city announcement. Last year, Pasadena announced a public information meeting to discuss an initial study and mitigated negative declaration for the project. The current agenda instead seeks a categorical exemption.

Council approval of the design concept and environmental determination would not itself authorize a construction contract.

Project funding and construction schedule

The city’s public stormwater project listing identifies approximately $2.2 million allocated for design and $16.75 million for construction.

The Department of Public Works previously conducted public outreach on the proposed improvements, including a September meeting at which residents were invited to review plans that had reached approximately 90% design completion.

Construction timing remains uncertain in the available public records. Los Angeles County’s Safe, Clean Water Program reporting portal lists the project in its design phase, with projected dates extending from May 2029 through December 2030.

The proposal represents an effort to address stormwater pollution in northwest Pasadena through underground infrastructure while incorporating improvements to an existing public parking area.

The City Council is scheduled to consider the project during its public meeting at 6 p.m. Tuesday, Oct. 20, in the Council Chamber, Room S249, at Pasadena City Hall, 100 N. Garfield Ave.