Milpitas, CA Environmental Rules: Erosion Control (2026)

Milpitas Municipal Code Section II-13-10, part of the Grading, Excavation, Paving and Erosion Control chapter, requires every erosion control plan filed with a grading permit application to meet Section XIII, Stormwater, of the City's Engineering Design Guidelines under Ordinance No. 66.3, and whichever of the two sets stricter conditions controls. The plan itself must carry the stamp of a registered Civil Engineer, and any site-stabilization measures in it must come from a registered Civil Engineer, Landscape Architect or Architect (Section II-13-10.01). It has to spell out land treatment, structural measures and a timing schedule sufficient to minimize soil erosion and sedimentation, and the Building Official reviews that plan for adequacy and can demand more supporting detail before approving it (Section II-13-10.02).

The plan must separately cover vegetative stabilization and protection of native plantings, drainage and runoff control, cut-and-fill construction, stockpiling, dust control and a clear map of what stays undisturbed (Section II-13-10.03). Cut and fill slope faces must be protected, usually with planting, installed as soon as practicable and before the Building Official signs off on final approval, though erosion-resistant material can skip that step (Section II-13-10.04); where planting alone will not hold, the Building Official can require check dams, cribbing or riprap (Section II-13-10.05). The Erosion Control Plan is a required exhibit under the Grading Permit application itself (Section II-13-7.03), planting called for in the plan must be finished within 90 days of grading completion (Section II-13-25.03), and sediment basins, traps or diversions must go in ahead of, or at the same time as, any clearing or grading and stay in place throughout construction (Section II-13-31.02).