City Environmental Panel Calls for Greater Oversight of $80 Million Stormwater Initiative

Pasadena’s Environmental Advisory Commission is pushing city leaders to establish independent technical oversight for $80 million in stormwater projects that will reshape the city’s water infrastructure for decades to come.

In a memorandum to the mayor and City Council, the commission recommended creating a Technical Advisory Committee to guide six park-based projects funded by Measure W. The committee would include city staff and outside experts in water engineering, groundwater management and native habitats.

The recommendation will be discussed at a commission meeting on Tuesday.

The commission compared the proposal to oversight provided during the Central Library Seismic Retrofit project.

“These complex and long-lived infrastructure projects require independent technical review to advise Council on design, operations, maintenance, and long-term costs,” the memorandum said.

The commission commended the Stormwater Program Administrator and Public Works Department for securing the substantial funding. Officials emphasized native habitat restoration and stormwater filtration in their plans.

But the commission raised concerns about transparency, long-term costs and whether projects will deliver promised environmental benefits.

The panel conducted a yearlong review that included consultations with water engineers, landscape architects, academics and advocates. That review revealed significant gaps in public documentation and understanding.

“Despite multiple community meetings, public understanding remains limited,” the memorandum notes. Inconsistent terminology and insufficient explanation of technical features have contributed to mixed public support.

The commission outlined seven specific recommendations beyond establishing the advisory committee.

Each project should include a publicly available engineering “Basis of Design” document, stamped and signed by a licensed professional engineer. Such documents would detail design assumptions, performance criteria, infiltration rates and maintenance requirements.

The commission urged the city to make groundwater recharge an explicit project goal. Currently, recharge is described as an “adjacent impact” rather than an objective.

Metropolitan Water District briefings have emphasized local supply resilience as Sierra Nevada snowpack is projected to decline 48 to 65 percent by century’s end.

“Pasadena should not miss opportunities to increase groundwater recharge where Measure W funding is available,” the commission stated.

The panel expressed particular concern about proposed subsurface infiltration galleries at multiple sites. Significant uncertainty surrounds their purpose, location, performance and maintenance costs.

At Eaton Wash, for example, benefits of a concrete subsurface structure remain unclear given extensive surface features already proposed. Long-term maintenance costs could span 80 to 100 years.

For projects in sensitive natural areas like the Arroyo Seco and Hahamonga, the commission recommended prioritizing nature-based solutions over concrete infrastructure. The Berkshire Creek project should serve as a standard, officials said.

The commission also called for detailed operations and maintenance plans. City staff would need targeted training in maintaining permeable pavements, infiltration systems and native habitats.

Local organizations like Theodore Payne Foundation and Council for Watershed Health should lead training efforts rather than out-of-region consultants, the commission recommended.

The six projects connect to a broader watershed system extending from the San Gabriel Mountains to the Raymond Basin and ultimately the Pacific Ocean. They should align with multiple adopted plans covering stormwater management and water resources.

The commission’s list of recommended technical advisors includes 10 experts. They range from a former Metropolitan Water District board member to a Tongva tribe ethnobotanist.

“These projects represent a rare opportunity to improve water quality, restore ecosystems, and strengthen local water supply resilience,” the memorandum concludes.

The commission urged the council to strengthen technical oversight, transparency and long-term planning to ensure projects deliver promised benefits.