San Luis Obispo drafts smaller sewer-capacity zones, expands outreach and incentives for private lateral repairs

San Luis Obispo City wastewater and utilities staff on a utilities-focused meeting previewed a new West Yost study that redraws the city's sewer capacity-constrained areas, increases real-time monitoring and outreach to private-property owners, and expands incentives for voluntary lateral replacement.

The proposal, which city staff described as draft, would shrink the map of constrained areas roughly 50% from the 2015 boundaries and shift some downtown constraints north; staff said Laguna-area constraints were removed after public and capital projects in that area. Chris Lehman, the city's wastewater deputy director, told attendees the city has reduced spills "from 34 [in 2021] to 1" this year on city infrastructure and said the new draft boundaries are driven by flow-monitoring and other updated data.

City officials said the new study is meant to update the 2015 collections master plan and will be finalized with West Yost within weeks. The staff report is scheduled for City Council in August; staff said they aim to publish final boundaries to the public portal in October and to make the boundary updates effective January 7.

Why it matters: San Luis Obispo's sewer system faces ongoing infiltration and inflow (I&I) problems from aging mains and private laterals. Those problems can create overflows that trigger enforcement and penalties from the State Water Resources Control Board and threaten public and environmental health. City staff framed the draft boundaries, expanded monitoring and outreach as a combined strategy to manage risk while targeting future capital and private-repair work.

What the city presented - Background: Staff said the city settled a lawsuit with RiverWatch in July…