Large Affordable Housing Project In San Mateo County Moving Forward

SAN CARLOS, CA — San Mateo County supervisors have approved the next phase of a project to bring dozens of new affordable homes to San Carlos, the County Executive's Office announced Monday.

The action allows MidPen Housing to begin designing a new housing community on three county-owned parcels in the 600 block of Walnut Street, near the city’s downtown. The project will include a minimum of 75 affordable homes.

“The City of San Carlos is pleased to partner with the County of San Mateo in reimagining this vacant site to deliver much-needed affordable housing for our residents and public employees,” San Carlos Mayor Pranita Venkatesh said in a county news release. “Its proximity to downtown and transit makes it a key opportunity site for advancing our affordable housing goals."

The county acquired the parcels — 626, 640 and 648 Walnut Street — in 2024 to create new affordable housing in a transit-rich part of San Carlos. The Department of Housing issued a request for proposals earlier this year seeking a developer with experience designing, financing and operating long-term affordable housing.

“The County is excited to move forward on this project and to work with our partners in the City of San Carlos and now, MidPen Housing,” County Executive Mike Callagy said in the news release.

MidPen Housing has partnered with San Mateo County on several high-profile projects and has a record of building and managing communities that serve low-, very low- and extremely low-income households, according to the county. The Walnut Street development would extend that work, with homes reserved for households earning up to 80 percent of the area median income under a long-term affordability covenant.

“We applaud the County and City’s leadership and commitment to affordable housing, and look forward to engaging with local stakeholders to create a community that will reflect shared priorities and serve generations to come," said Matthew Franklin, president and CEO of MidPen Housing, in the news release.

Ten qualified developers submitted proposals. Following interviews, the committee unanimously recommended MidPen Housing.

With the board’s approval, county staff and MidPen Housing will move forward with community engagement in 2026 to shape the project design and prepare for entitlement applications for review by the city of San Carlos.