Riprap and toe protection in Islamorada

Signs the toe needs work

Look for these at low tide.

• A gap or hollow under the base of the wall
• Wall tipping toward the water
• Soil loss behind the wall with no visible crack
• Strong wakes or currents along the lot

Seawalls and riprap inside the setback

Islamorada's shoreline setback keeps buildings 20 to 50 ft from mean high water, but it does not apply to seawalls, riprap and bulkheads whose purpose is erosion control or upland protection. Because the Keys are an area of critical state concern, the 2024 ordinance was approved by the Florida Department of Commerce.

Toe protection usually costs a fraction of a new wall and fits that permit route.[1]

No tying up to mangroves

Islamorada bans docking, mooring or tying a vessel to shoreline vegetation, mangroves included, except in a declared emergency. A boat needs a proper dock or piling to tie to, which is often the reason a new dock or mooring pile is the first project on a natural shoreline lot.

Rock is placed around existing mangroves, not over them.[1]

The Lignumvitae Key Aquatic Preserve

The 6,700 acre Lignumvitae Key Aquatic Preserve lies inside the Village between Upper and Lower Matecumbe Keys, with seagrass meadows and three navigable channels between Florida Bay and the Atlantic. It is recognised as an outstanding water resource of the state, which brings the smaller 500 sq ft dock exemption used for Outstanding Florida Waters.

Rock footprints are kept off grass beds, so a survey of the bottom comes before the rock order.[2][3]

Sanctuary water from the high tide line

The Florida Keys National Marine Sanctuary begins at the mean high water mark, so any dock, lift or pile work in Islamorada is Sanctuary work and needs the matching state and federal approvals. Monroe County waters carry FWC boating restricted areas under rule 68D-24.144 and the state manatee conditions.[4][5][6]

What makes Islamorada different

Principal buildings sit 20 ft from the mean high water line on altered shorelines such as canals, 30 ft on open water with conditions, and 50 ft on unaltered shorelines. Docks, lifts, davits, seawalls and riprap are water-dependent structures that may sit inside that setback under the Village's standards.[1]

Sanctuary and manatee layers

The federal small-project permit, SPGP VI, required Sanctuary sign-off before any Islamorada project in Keys waters, and crews follow the state manatee conditions on every in-water job.[7][6]

Permits in Islamorada

• Islamorada, Village of Islands, Planning and Development Services: Docks, lifts and shoreline structures under Village Code Chapter 30.
• Florida Keys National Marine Sanctuary: Sanctuary waters surround every Islamorada key from the mean high water mark; we confirm what Sanctuary approval each project needs.
• Florida DEP or South Florida Water Management District: State permit or exemption; part of the Village's water is the Lignumvitae Key Aquatic Preserve.
• US Army Corps of Engineers, Jacksonville District: Federal authorisation for work in the Sanctuary waters around the Village.

What riprap does

Riprap is a sloped layer of large rock at the base of a seawall. It breaks wave energy and stops the water from scouring sand out from under the toe. Red mangroves can grow between the rocks, which is the idea behind living shorelines.

Riprap limits and permits

Under SPGP VI, new riprap may extend no more than 10 ft waterward of the mean high water line, and repair or replacement no more than 18 inches beyond the previous footprint. Miami-Dade allows natural limerock boulder riprap on a 2:1 slope up to 10 ft waterward through an expedited authorisation after inspection.[7][11]

Frequently asked questions