Accessory dwelling units: private sewage disposal systems.

The determination that an existing private sewage disposal system is verified to be functioning properly and has capacity to serve an additional ADU is now explicitly made by the local health officer, rather than being stated as a passive condition. This clarifies who bears responsibility for the assessment.

Added reference to 'the local agency management program approved by the regional water quality control board' as part of the operating requirements that a private sewage disposal system must meet for lot size purposes. This incorporates the regional board's approval role into the statutory framework.

Added cross-reference in subparagraph (B) to 'the operating requirements described in subparagraph (A)' to clarify that both subparagraphs rely on the same set of operating requirements.

The provision protecting homeowners from being forced to install new septic systems now requires verification by a qualified professional that the existing system is functioning properly and has capacity, with the determination based on SWRCB operating requirements under Water Code Section 13291 for that lot size. Previously, the bill simply stated the system 'is functioning properly' without specifying who determines this or what standard applies.

A standalone section stating the Legislature's intent to enact legislation to streamline permitting for accessory dwelling units in rural areas was removed from the bill entirely.

Assembly Member Patterson was added as a coauthor of the bill.

The fiscal committee vote changed from no to yes, and the state-mandated local program designation was confirmed as yes, indicating the bill now carries a state-mandated local program with no reimbursement required because local agencies can levy sufficient fees.

The bill now amends Section 66314 of the Government Code rather than merely stating legislative intent. It imposes binding requirements on local agency ADU ordinances statewide.

Prohibits a local agency from prohibiting an ADU in an area solely because the lots are served by private sewage disposal systems rather than a public sewer system.

Prohibits a local health officer from withholding approval based on a minimum lot size requirement if the private sewage disposal system meets operating requirements established by the State Water Resources Control Board for that lot size.

Prohibits a local health officer from requiring installation of a new or alternative sewage system as a condition of ADU approval if the existing system is functioning properly and has capacity to serve the additional load, unless there is specific substantial evidence of a present risk to public health or water quality.

Adds a full set of ADU ordinance requirements including: maximum parking of one space per unit or bedroom (whichever is less), setback limits of no more than four feet from side and rear lot lines, detached ADU size cap of 1,200 square feet, attached ADU limited to 50 percent of primary dwelling floor area, no fire sprinkler requirement if not required for the primary residence, and no replacement parking requirement when a garage is demolished or converted.

The fiscal analysis changed from 'no' to 'yes' for both the fiscal committee and state-mandated local program, indicating the bill now imposes costs on local agencies. A new Section 2 states no reimbursement is required because local agencies can levy service charges, fees, or assessments to cover the mandated program.