Seawall inspections in Islamorada

When to book an inspection

Book one when something changes, not only when something breaks.

• After a city citation or warning
• Before buying or selling a waterfront home
• After a hurricane or a run of king tides
• When you see new cracks, stains or sinkholes

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.

The inspection notes which repairs are exempt and which need a permit.[1]

Watch the datum: about 1.5 ft

The Village notes that converting from NGVD29 to NAVD88 shifts elevations by about -1.5 ft on average in Monroe County, and the shift varies from place to place. Old plans and new maps use different datums, so a cap or floor height has to be converted before anyone compares numbers.

Every inspection records the cap elevation against that standard.[2]

Bay side and ocean side tides differ fourfold

NOAA's Florida Bay gauge at Upper Matecumbe Key shows a great diurnal range of only 0.61 ft, with mean higher high water about 0.41 ft below NAVD 88, while the Hawk Channel gauge a short way across the key shows 2.28 ft (1983 to 2001 epoch). A lift or floating dock sized for one side of Islamorada is wrong for the other.

We inspect at the lowest tide of the week so the lower wall face and the toe are visible.[3][4]

Flood maps from 2005, new ones pending

Islamorada still builds to effective flood maps dated 18 February 2005. Preliminary maps went through appeals between March and June 2021, FEMA has not announced when they take effect, and the Village has promised six months' notice once it does.[2]

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.[5][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 we check

We walk the full length of the wall from the land and the water.

• Cap: cracks, spalling, rust staining, height against the local standard
• Face and panels: cracks, open joints, lean
• Tiebacks and anchors: signs of movement
• Toe: scour or undercutting
• Land side: sinkholes, soft ground, weep holes

Who is responsible for a private seawall?

The property owner. Miami Beach requires owners to correct walls that let tidal water flow over or through them and can cite owners with no seawall at all. Fort Lauderdale presumes a wall is in disrepair if it lets upland soil erode, material pass through it, or tidal water flow onto neighbours or the street, and gives owners 60 days to show progress and 365 days to finish.[7][8]

Frequently asked questions