Modesto, CA Fence Regulations: Retaining Walls (2026)

502 of the Modesto Municipal Code lists work exempt from permit requirements under the adopted 2022 California Building Code, and subsection (d) specifically covers retaining walls: those not over four feet in height, measured from the bottom of the footing to the top of the wall, do not need a building permit, unless the wall supports a surcharge or impounds Class I, II, or IIIA liquids, in which case a permit is required no matter the height. The exemption sits alongside similar height-based carve-outs in the same section, such as fences not over seven feet and water tanks under five thousand gallons with a 2:1 height-to-diameter ratio, all adopted under Ord.

No. and amended through Ord. No. S. 502 opens by clarifying that a permit exemption never authorizes work that otherwise violates the Code or any local, state, or federal law: an exempt retaining wall must still meet structural, drainage, and property-line standards. 501 and submit construction documents under Article 6, and taller walls typically require engineered plans given the added lateral soil and surcharge loads the Building Official reviews. 507 and rejecting incomplete submittals in writing.