RIVERSIDE — Riverside County supervisors on Sept. 1 had a public hearing on a countywide zoning text amendment that would change rules for accessory dwelling units, junior ADUs, and SB 9 units in unincorporated communities, including East Hemet, Valle Vista, Winchester, Sage, and the Anza fringe.
The item is CZ2600012, Ordinance No. 348.5056. Staff’s Form 11 framed Sept. 1 as introduction and public hearing. The recommended motion was to introduce the ordinance, waive further reading, and adopt it on successive weeks. The minutes for that meeting have not been published. The ordinance’s signature and adoption-date lines in the packet are blank. This newspaper does not treat the ordinance as adopted.
Staff wrote that the amendment would reorganize Article XIXj of Ordinance 348, update ADU and JADU rules, and add SB 9 units “consistent with State law through January 1, 2026.” The county claims a CEQA exemption.
As drafted, the ordinance would apply to all unincorporated Riverside County. Housing types listed in Article XIXj would include ADUs, JADUs, SB 9 units, second units, guest quarters, ranchets, and multiple-owner group units.
The Form 11 says the ADU maximum size would go to 1,600 square feet, from 1,000. Attached ADUs would be limited to 50 percent of the primary dwelling or 1,600 square feet, whichever is less, but the 50 percent cap would not preclude at least 1,000 square feet. A detached ADU on a single-family lot could be 1,600 square feet.
On a lot with an existing multifamily dwelling, the draft would allow up to eight detached ADUs, not more than the number of existing units.
Owner occupancy would not be required. The draft text says property owners “shall not be required to occupy, or reside within, either the primary dwelling or ADU located on the same lot.”
The draft would legalize some unpermitted ADUs and JADUs built before Jan. 1, 2020, under Government Code section 66311.7. Manufactured homes could count as ADUs. A JADU would be limited to 500 square feet, entirely within a single-family dwelling.
SB 9 units would implement Government Code sections 65852.21 and 66411.7. Twelve zones are listed as single-family residential for SB 9 purposes: A-1 (2.5 acres or less), R-1, R-1A, R-A, R-D, R-R, R-T, R-T-R, R-T-R-1, SP, W-2, and W-2-M. The packet says inclusion of a zone does not by itself establish eligibility. Urban lot splits would be handled separately in Ordinance 460.
Second units would remain separate from ADUs. On lots of 20,001 square feet to 2 acres, the second-unit maximum would rise from 1,200 to 1,600 square feet. Guest quarters would remain accessory, not independent dwellings. Ranchet and multiple-owner group rules would remain limited to the Eastern Coachella Valley.
A new section would let the planning director, or a designee, elevate a Director’s Hearing item to the Planning Commission if there are significant policy questions, public controversy, or substantial community impacts.
If later adopted, the ordinance would take effect 30 days after adoption, according to the draft.
The Planning Commission recommended the amendment 4-0 on July 8, 2026, according to the Form 11 background. That is not a Board of Supervisors vote.
The next listed Board meeting is Tuesday, Sept. 15, 9:30 a.m., 4080 Lemon St., Riverside. When checked on Sept. 2, that agenda page did not list Ordinance 348.5056. No second-reading date is printed in the Sept. 1 packet.
