Kenai Peninsula Borough, AK Environmental Rules: Erosion Control (2026)

In the Kenai Peninsula Borough outside the cities, the only codified erosion control regime sits in KPB Chapter 21.18, the Anadromous Waters Habitat Protection District. KPB 21.18.040 establishes the district as all land within 50 horizontal feet of the ordinary high water mark of a listed anadromous water, extended to 25 feet back from the top of a cut bank of 60 degrees or more where banks are steep. KPB 21.18.010 finds that bank erosion, bank trampling and unsuccessful remedial attempts have damaged salmon habitat, and KPB 21.18.020 lists decreasing significant erosion and sedimentation among the chapter's purposes.

Under KPB 21.18.091, planning department staff can require mitigation measures for a proposed, ongoing or completed project's impacts to the district, starting with 'standard erosion and storm water runoff control measures' and extending to restoration of native vegetation, removal of non-conforming accessory structures, or agreed measures such as removing seawalls and riprap or evaluating a failing septic system. Conditional use permits issued under KPB 21.18.081 must also meet the general standard that the use will not cause significant erosion or sedimentation. Permits and mitigation plans are filed with the river center, and the planning department can revoke a permit under KPB 21.18.082 after 15 days' written notice if conditions are not corrected.

Violations of the chapter are enforced under KPB Chapter 21.50, with each day of continuing violation counted separately under KPB 21.18.110. None of this applies to grading or erosion outside the 50-foot habitat strip; the borough has no general building or grading code, so an inland construction site is not subject to a borough erosion permit.