PUC outlines grant, code and acquisition options to reduce neighborhood flood risk

The San Francisco Public Utilities Commission on Tuesday endorsed a staff proposal to expand non‑capital flood‑resilience tools for neighborhoods that remain at high risk during storms larger than the utility's 5‑year design standard.

Stephanie Harrison, project manager with the PUC, summarized a three‑tier approach: maintain the 5‑year storm as the engineering design standard for the collection system, use a 25‑year core‑flood map to determine eligibility for grants and mandatory resilience requirements, and publish a 100‑year map for disclosure and public notification. "The 25‑year design storm would be used for eligibility for programmatic strategies like grants and also requirements like changing the building code," Harrison said.

The staff proposal would expand a current, under‑utilized grant program to cover four categories of property‑level projects: plumbing modifications (for example, backwater valves and pumping arrangements), dry flood‑proofing (sealing doorways and removable panels), wet flood‑proofing (use of cleanable interior finishes, elevated utilities), and selective elevation of structures as a last resort. Harrison said eligibility would begin in mapped 25‑year core flood areas, with an opt‑in process for other properties that experience local or plumbing‑related flooding.

To help homeowners navigate technical choices, staff proposed prequalified contractor lists and interdepartmental on‑site assessments that could include the Department of Building Inspection and PUC hydraulics staff. "We'd have a menu of project types to help address different problems," Harrison said, describing a planned on‑site assessment and streamlined application process.

Commissioners focused on deliverables, funding and timing. Eric Sandler, CFO, and Harrison said the PUC has a line item for grants in the current budget. Staff said the program was originally planned at about $2 million, with actual allocations to date under $500,000 and approximately $180,000 granted so far; they expect to provide exact budget numbers following the meeting. Staff said they hope to expand and streamline plumbing modifications and wet/dry proofing support and begin outreach with communities so some assistance could be available this winter.

Staff also recommended regulatory and program changes tied to transactions and major plumbing renovations: requiring backwater valves for low fixtures at point of sale or during major renovation and televising and repair of sewer laterals as a condition of sale or substantial renovation. Harrison said the PUC will explore financing options to mitigate equity concerns so that low‑income homeowners can comply without bearing unaffordable costs.

The presentation stressed tradeoffs between raising the citywide level of protection and affordability. Harrison noted staff estimates that fully addressing 25‑year flood exposure across the city would require multibillion‑dollar infrastructure investments; the programmatic strategies are intended to complement capital projects and provide faster relief to the most vulnerable properties.

The commission asked staff to finalize implementation steps—including lead agencies, schedules and funding needs—and to prioritize community outreach and multilingual communications in neighborhoods most affected by flooding. Staff said outreach and a rollout plan remain in development, and that the PUC will return with an implementation plan that specifies costs, schedules and lead departments.