Dock construction in Key Largo

Who this is for

Owners adding a first dock, replacing a dock that is beyond repair, or redesigning a dock for a new boat or lift.

The special exception process

Owners describe the submerged lands the dock crosses (sand, seagrass, corals) and the minimum extra length needed to reach adequate depth, with a site plan by a Florida registered architect, engineer or landscape architect.[1]

Federal and Sanctuary layer

Projects inside the Florida Keys National Marine Sanctuary needed prior Sanctuary approval under SPGP VI, and docks over seagrass follow federal piling-supported structure guidelines.[2]

10% of the water, 25% with the boat

Monroe County Code 118-12(m) keeps a Key Largo dock to 10% of the waterbody width, measured mean low water to mean low water, and the dock together with the moored boat and any lift to 25% of the navigable width. On a 50 ft canal that is a 5 ft dock.

We design new docks to that limit first, then fit the boat and the lift around it.[4]

Four feet of water, and more over grass

A Key Largo dock must end in at least 4 ft of water at mean low water. Over seagrass or hard bottom, the water must be 4 ft deep above the organisms, the deck at least 5 ft above mean high water, and the terminal platform no larger than 160 sq ft (8 by 20 ft), with a benthic survey to prove it.

A bottom survey comes before the layout so the dock clears any grass.[4]

What makes Key Largo different

The special exception application asks owners to describe the submerged lands the dock crosses, such as sand, seagrass or coral, and the minimum extra length needed to reach adequate water depth. The site plan must be prepared by a Florida registered architect, engineer or landscape architect and show the mean high water line and shoreline setbacks.[1]

Sanctuary, seagrass and manatees

Projects inside the Florida Keys National Marine Sanctuary needed prior Sanctuary approval under SPGP VI. The same permit let boat lifts and minor structures in Monroe County go into existing boat slips without a seagrass survey. All in-water work follows the state manatee conditions.[2][5]

Permits in Key Largo

• Monroe County Planning and Environmental Resources Department: Dock length special exceptions under County Code section 118-12(m)(15).
• Florida Keys National Marine Sanctuary: The Sanctuary starts at mean high water, so Key Largo canal and bay work is inside it; SPGP VI required its prior approval.
• Florida DEP or South Florida Water Management District: State permit or exemption, which Monroe County needs to see before it issues a Notice to Proceed for docks, seawalls and ramps.
• US Army Corps of Engineers, Jacksonville District: Federal permit, also required before the County's Notice to Proceed.

How a new dock gets built

1. Survey of the shoreline, water depth and any seagrass
2. Design and engineered drawings
3. County, city and state approvals
4. Pilings driven or jetted, with manatee precautions
5. Framing, decking, cleats and lighting
6. Final inspections

Seagrass and dock design

In Johnson's seagrass range, which runs from Palm Bay south to central Biscayne Bay, docks over seagrass must follow federal minor piling-supported structure guidelines. In aquatic preserves a single-family dock is limited to a 4 ft wide walkway and a 160 sq ft terminal platform, and may not extend more than 500 ft or 20% of the waterbody width.[2][9]

Neighbours and view lines

Miami-Dade uses a D-5 boundary to protect neighbours' view and access. A dock beyond it may need consent letters from adjacent owners.[7]

Frequently asked questions