A four-story office building that once anchored Southern California Edison's corporate footprint in Rosemead is on track to be demolished and replaced with 191 new townhomes, under a proposal headed to the city's Planning Commission this month. City records list an entity affiliated with the Lewis Group of Companies as the owner and applicant for the project at 1515 Walnut Grove Avenue, which would tear down the existing 268,000-square-foot office building and a detached central plant to make way for 27 three-story residential structures.
Planning Commission Set to Weigh In
The City of Rosemead's Planning Division has scheduled a public hearing before the Planning Commission for September 23, following a 20-calendar-day public comment window that ran from August 27 to September 16, according to a City of Rosemead public notice. As reported by Urbanize LA, the full project scope calls for demolishing the four-story office building and a detached central plant building across 9.28 acres to build the 191 townhomes, totaling roughly 238,616 square feet of residential floor space excluding attached garages.
The homes would include a mix of two-, three-, and four-bedroom units, per the outlet's report, combining tandem and row townhome layouts. The buildings are designed in a Mediterranean style by Woodley Architectural Group, arranged around private roads, walkways, and open spaces, with parking, on-site open space, and other amenities woven throughout the site.
From Savings and Loan Data Center to Edison Campus
The property has cycled through several major institutional uses since it was built. The office complex was originally constructed in 1983 as a data center for California Federal Savings and Loan, later occupied by Countrywide, before Southern California Edison acquired it in March 2010 for $33.75 million, according to GlobeSt reporting on the sale at the time.
Edison operated the site as its General Office Building #5 for well over a decade. In May 2025, a California Public Utilities Commission administrative law judge issued a decision approving Edison's application under Public Utilities Code Section 851 to sell its ground lease interest and the Building #5 campus to developer affiliate 1515 Walnut Grove, LP, clearing a key regulatory hurdle since the utility held a ground lease interest on the parcel.
Unit Count Grew Since Early Pitch
The developer's ambitions for the site have grown since its earliest pitch to the city. In January 2024, Lewis Group of Companies submitted a pre-application proposal for a 178-unit townhome layout at the site, before expanding the density to 191 units in its formal entitlement filings, according to a City of Rosemead City Council agenda from that period. That original 2024 concept envisioned 105 tandem townhomes and 73 row townhomes ranging from 1,147 to 2,201 square feet.
Founded in 1955 in the San Gabriel Valley, Upland-based Lewis Group of Companies has developed more than 57,000 homes, 11,000 apartment units, and 19.5 million square feet of commercial space, according to a city workshop presentation on the firm's background. Per Urbanize LA, construction is expected to take roughly 34 months following groundbreaking, should the project move forward.
Zoning Change and Environmental Review
Getting there requires more than a building permit. The parcel is currently designated Office/Light Industrial in Rosemead's General Plan and zoned Medium Commercial with a Design Overlay, so the housing development requires approval of a general plan amendment to High Density Residential along with a zone change to Planned Development, per the city's public notice.
The city's environmental Initial Study determined that potential environmental impacts could be reduced to less-than-significant levels through mitigation measures, including biological monitoring during initial ground disturbance and Swainson's hawk avoidance protocols, according to filings with the California State Clearinghouse. A Mitigated Negative Declaration was prepared for the project rather than a full Environmental Impact Report. In December 2025, traffic consultants also completed a Vehicle Miles Traveled technical analysis to demonstrate compliance with Senate Bill 743 and local transportation assessment guidelines, a state standard that assesses transportation impacts using VMT rather than older vehicle-delay measures.
Part of a Larger Housing Push
The project also lands amid state pressure on Rosemead to add housing stock. The Southern California Association of Governments assigned the city a Regional Housing Needs Allocation target of 4,612 new housing units for the 6th cycle planning period spanning 2021 through 2029, according to the city's adopted Housing Element, and California cities face legal pressure to rezone underutilized commercial sites to help meet those quotas.
Whether the Planning Commission approves the project on September 23, and what public comments emerge over traffic or environmental mitigations during the review, remains to be seen. It's also unclear whether any low-income affordable housing units will be built into the final entitlement package, an open question tied to the city's broader housing element goals.
