WallDockDeck
Key Biscayne · Miami-Dade County

How big a dock can I build in Key Biscayne?

10 ft or 10% of waterway widthcanal lots, whichever is less; 40 ft on the bayfront

Key Biscayne sets dock reach by location. A canal dock may project 10 ft or 10% of the waterway width, whichever is less; in Hurricane Harbor and Smuggler's Cove 20 ft or 20%; and on the bayfront 40 ft from the property line, with docks and lifts kept inside a 60-degree triangle. Each property gets at most two boat slips.

Source: Village of Key Biscayne Code Ch. 30 (Zoning and Land Development Regulations) Sec. 30-100(4); Miami-Dade County Code Secs. 24-48.1(1)(a), 24-48.3(1)(j),(3); Fla. Stat. 403.813(1)(b) (2026); 33 CFR 322.3(a) · Verified 2026-10

The detail

CanalDock projection 10 ft or 10% of the waterway width, whichever is less; mooring piles 25 ft from the bulkhead or 20% of the width, whichever is less - Village Code 30-100(4)
Hurricane Harbor and Smuggler's CoveDock projection 20 ft or 20% of the width, whichever is less; mooring piles 35 ft or 20%; a boat may not extend past the end of a perpendicular dock by more than 10% of that dock's length - 30-100(4)
BayfrontDock projection 40 ft from the property line; up to 100 ft including piles at 1, 3, 5, 7, 9 and 11 Harbor Point with the neighbours' written consent; mooring piles up to 20 ft from the dock and no more than 55 ft apart - 30-100(4)
Bayfront triangleThe dock or lift must sit inside a 60-degree triangle with a baseline of at least 100 ft (not required at the Harbor Point addresses above); piles, lift arms and boats may lie outside it - 30-100(4)
Parallel lengthA dock may run no more than 55 ft parallel to the bulkhead - 30-100(4)
No docksDocks and moorings are prohibited at 400 Harbor Drive through 500 Bay Lane
SetbacksThe zoning district's setbacks extend into the water for docks, davits, fender piles, mooring piles and boats; no part of a watercraft, including engines and dive platforms, may encroach - 30-100(4)
Lifts and pilesMooring piles no taller than 13 ft NGVD; a boat on a lift no more than 6 inches above mean high water; fender piles within 18 inches of the bulkhead where a dock will not fit - 30-100(4)
SlipsNo more than two boat slips per property, plus one guest boat for up to 24 hours - 30-100(4)
MangrovesWhere mangroves exist, measurements are taken from their water's edge - 30-100(4)
ApprovalWritten approval of the Building, Zoning and Planning Department before construction; the Village may deny a dock that harms safe navigation - 30-100(4)
RebuildingA legal nonconforming dock may be re-decked or repaired in its footprint, and rebuilt after a natural disaster if a permit is obtained within two years - 30-100(4)
Miami-Dade County Class I permitAny work in, on, over or upon tidal waters or bay bottom anywhere in Miami-Dade County, cities included, needs a county Class I permit - County Code 24-48.1(1)(a). New boat slips at docks in tidal waters need at least 4 ft of water at mean low water; the depth rule does not apply to docks in bulkheaded artificial canals bordered by uplands on both sides, to lifts, davits and piles in slips at existing permitted docks, or to repair of existing legal docks with at least 3 ft of water - 24-48.3(3). A dock proposed beyond the boundaries in Sec. D-5(03)(2)(a) of the county Public Works Manual gets extra review factors - 24-48.3(1)(j)
State exemptionA private, non-commercial dock on pilings with 1,000 sq ft or less of over-water surface (500 sq ft in Outstanding Florida Waters), and the only exempt dock along 65 ft of shoreline (or one per lot if the lot is narrower), needs no state environmental permit - Fla. Stat. 403.813(1)(b). The exemption does not grant permission to use state-owned submerged lands and does not override city or county rules - 403.813(1)
FederalStructures in navigable waters need a Department of the Army permit, general or individual - 33 CFR 322.3(a)

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