WallDockDeck
Marathon · Monroe County

Do I need a permit to repair a seawall in Marathon?

Yescity permit; state/federal approvals first

Yes. Marathon requires anyone doing bulkhead, seawall or riprap work in surface waters to file a natural resources inventory or similar notice and get all federal, state and water management district approvals and a city permit first. Replacing a deteriorated wall is allowed, but no new vertical seawalls on open water, and hardening only where the City Biologist finds riprap will not do.

Source: Marathon LDR Secs. 106.36, 106.38 (municipalcodeonline); s. 403.813(1)(e), F.S. (2026); 33 CFR 322.3(a) · Verified 2026-10

The detail

CityApplicants must submit a natural resources inventory or comparable administrative notice and 'must obtain all necessary federal, state and water management district approvals and a permit from the City prior to initiating' the work; bulkheads, seawalls and riprap must meet the Hardened Shorelines rules - LDR Sec. 106.38. Hardened vertical structures only on residential canals and altered shorelines where riprap or sloping revetments with biotechnical erosion control will not suffice as determined by the City Biologist; allowed when replacing an existing deteriorated bulkhead or seawall; no new vertical seawalls on open water - Sec. 106.36. Designs must include a six-inch retention swale, berm or curb landward of the wall; caps may be two feet wide; the bulkhead line is the average mean high water line when the permit is requested, and reclaiming eroded land by bulkheading and backfilling is prohibited - Sec. 106.36
StateRestoring a seawall at its previous location, upland of it, or within 18 inches waterward is exempt from a state environmental resource permit; the exemption does not replace permission to use state-owned submerged land or county and city requirements, and does not cover chapter 161 coastal permits - s. 403.813(1), (1)(e), F.S.
FederalA U.S. Army Corps of Engineers (Department of the Army) authorization is required for structures or work in or affecting navigable waters, unless exempt or covered by a nationwide or regional general permit - 33 CFR 322.3(a) (Rivers and Harbors Act s. 10)

Your city's height sheet

The elevation your city requires, the datum it is measured in, and the section of code that says so. One page.

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The county rule behind this

What applies across Monroe County, and where each city departs from it.

Monroe CountySeawall requirements county-wide

The same question, nearby

The rule changes at the city line, not the county line.

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Twelve signs a seawall is failing

What to look for, where to look for it, and what it means when you find it. Walk your wall in twenty minutes.

A screening sheet for owners, not an engineering inspection.

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