What do I need to build or rebuild a dock in the Keys?
Start with two facts: is the water a dredged canal or open water, and who owns the bottom? Those two answers decide the state size limit, the surveys and the paperwork.
Dredged canals sit outside the Florida Keys Outstanding Florida Waters; natural shorelines and open water are inside. Rule 62-302.700 That one line changes how big a dock can be before it needs more than an exemption.
When should I call about a dock or boat lift?
- A storm damaged your dock. The state repair exemption is tied to damage within the last year. Rule 62-330.051(5)
- You want to add a lift or davit to a dock or seawall cap.
- Your dock would cross or end over seagrass, coral or sponges.
- You are buying a home and the dock’s permit history is unclear.
- Your dock needs to be longer than the code allows to reach depth.
Canal or open water: which dock rules apply in the Keys?
| Rule | Dredged canal | Open water |
|---|---|---|
Outstanding Florida Waters Rule 62-302.700 | Excluded | Included |
State dock exemption size F.S. 403.813(1)(b), (i) | 1,000 square feet or less | 500 square feet or less |
Monroe County water depth at the dock end Monroe County code 118-12(m)(6) | At least 4 feet at mean low water; pre-1986 canals have their own rule | At least 4 feet at mean low water, with open access |
Docks ending over seagrass or hardbottom Monroe County code 118-12(m)(6)e | Rare on dredged canals | 4 feet of water above the tops, decking 5 feet above mean high water, platform up to 160 square feet |
Marathon seafloor (benthic) survey Marathon dock checklist | Not on the checklist | Required along open water |
The state exemption only covers state environmental review. County, sanctuary, submerged-land and Corps review still apply. F.S. 403.813
Who owns the bottom under my dock?
Monroe County is carved out of the state’s no-application consent for using state-owned bottom. A new exempt dock over state bottom in the Keys needs written authorization, such as a letter of consent. Rule 18-21.005(1)(b)
Repairs are treated differently. Dock repair in the same place, and seawall or riprap repair, stay eligible for consent by rule. Rule 18-21.005(1)(b) A dock built to moor 10 or more vessels in Monroe County needs a submerged land lease. Rule 18-21.005
Many canal bottoms are privately owned, and an address does not tell you which. Ask DEP’s Marathon office at (305) 289-7070 before you design. DEP Marathon office DEP submerged lands overview
Can I rebuild a storm-damaged dock in the Keys?
Often, if you rebuild what was there. Florida exempts dock repair or replacement that uses no fill, stays within 5 feet of the same location and is no larger. Rule 62-330.051(5) The dock must have been working, or made unusable within the last year by an event such as a storm.
- Layton: the comprehensive plan lets structures destroyed by an act of God be rebuilt to their original dimensions. Layton Coastal Management Element
- Marathon: a nonconforming dock more than 50% damaged must be rebuilt to current rules where possible. Marathon code 108.20
- Key Colony Beach: docks that were nonconforming in 1971 may be repaired if the cost stays within 50% of the structure’s total construction cost. KCB Code 5-65
- DEP self-certification: the online dock self-certification is free, but in Monroe County it is not full state approval. DEP ERP e-Permitting
What are Monroe County’s dock rules?
| Item | Limit |
|---|---|
Width of the dock Monroe County code 118-12(m)(2), (4) | No more than 10% of the waterbody width; dock plus boat or lift no more than 25% of the navigable width |
Pier dock Monroe County code 118-12(m)(15) | About perpendicular, 4 feet wide, 5 feet from side lines, length the lesser of twice the frontage or 100 feet |
Terminal platform Monroe County code 118-12(m)(15) | Up to 160 square feet of grated decking, 8 feet in one dimension |
Marginal dock along a seawall Monroe County code 118-12(m)(13) | Full shoreline length, no wider than 8 feet or 10% of the waterbody, whichever is less |
Pilings Monroe County code 118-12(m)(6) | Non-leaching material, or 30-mil sleeves from 6 inches below the bottom to 2 feet above mean high water |
Lift setbacks Monroe County code 118-12(m)(3) | Davits 5 feet, elevator lifts 7.5 feet, floating lifts 5 to 10 feet from side lines extended |
Longer dock to reach depth Monroe dock length exception form | Special exception: $1,450 plus $3 per shoreline owner within 300 feet for mailed notice |
How do dock rules differ in Key West, Marathon, Key Colony Beach and Layton?
| City | Key dock rules | Office |
|---|---|---|
Key West | No approval until state and federal compliance is shown, with an environmental component on seagrass, hardbottom and manatees. Protection extends 600 feet into tidal water. Key West Code 110-186 Key West Code 110-183 | (305) 809-3956 Key West Building Department |
Marathon | Length up to the shoreline width, 100 feet, or 10% of the waterbody; minus 4 feet at the dock end; one dock per home; lifts no more than 5 feet above the dock or cap. Marathon code 104.64 Marathon code 104.64 Marathon code 104.64 | (305) 289-5052 Marathon Building Department |
Key Colony Beach | One dock per lot, extending only 5 feet into most canals. Elevator lifts up to 31,000 pounds; cradle lifts need Commission approval outside 7th Street and Marina Subdivision No. 2; hydro and pontoon lifts are banned. KCB Code 5-35 KCB Code 5-43 KCB Code 5-44 | (305) 289-1212, ext. 3 Key Colony Beach Building Department |
Layton | Docks capped at 10% of a confined waterbody, terminal platforms at 8 by 20 feet, walkways over mangroves at 5 feet wide. Layton Coastal Management Element | City Hall (305) 664-4667 Layton City Hall |
Key West’s dock checklist asks for a survey, site photos, the mean high-water line on the site plan and signed, sealed drawings. Key West dock checklist Marathon’s asks for a survey under 6 months old, DEP and Corps approvals, and questions go to the City Biologist at (305) 289-4121. Marathon dock checklist
When do the sanctuary and the Army Corps review a dock?
The sanctuary’s seagrass survey window runs June 1 to September 30. The 2026 window has closed, so a dock that needs a survey waits until June 1, 2027. Sanctuary survey protocol
- NOAA lists dock installation and seawall repairs that could affect corals among nearshore work needing sanctuary review. Sanctuary nearshore permits
- For dock or seawall work, the sanctuary will likely ask for a seafloor (benthic) survey. It queues a project only once plans, state approval, any survey and federal approval are all in. Sanctuary nearshore permits
- Surveys cover at least 10 feet beyond the work and 5 feet around each piling, done by a biologist holding a sanctuary permit. Sanctuary survey protocol
- Apply at least 90 days before the start you want. Sanctuary permits page
- Army Corps, Keys Permits Section: (305) 526-7181. Its Keys general permit, SAJ-82, expired June 24, 2026. Army Corps Keys Permits Section Army Corps permit SAJ-82
- The 2026 nationwide permits took effect March 15, 2026, and holders of a Corps nationwide or general permit still send their file to the sanctuary. USACE 2026 nationwide permits Sanctuary nearshore permits
Is my dock in an aquatic preserve?
On Big Pine Key’s ocean side, it may be. Coupon Bight Aquatic Preserve covers about 5,400 acres south of Big Pine Key, out to the 12-foot depth line. DEP Coupon Bight page
Private docks in a preserve are limited to the lesser of 500 feet or 20% of the waterbody width, a 4-foot walkway and a 160-square-foot platform, reaching only to minus 4 feet at mean low water. Rule 18-20.004(5) See the Big Pine Key guide.
What does a Keys dock or boat lift permit cost?
| Office | Fee basis |
|---|---|
Key West Key West Code 14-2 | $36 per $1,000 of contract price, $100 minimum |
Marathon Marathon Res. 2025-73 | Same rate as its seawalls, for new docks, dock repair, boat lifts and davits |
Key Colony Beach KCB Res. 2026-01 | $100 flat up to $2,500, then $35 per $1,000 or part |
Monroe County Res. 277-2025 Res. 277-2025 | $236 flat under $5,000; banded rates above; $976 Notice to Proceed when state or federal approval is required |
Construction cost depends on length, pilings, lift capacity and access. Surveys and engineering add to it. Build a full budget with the cost guide.
What to ask before you sign for a dock or lift
- Is this a canal or open water, and which state exemption size applies?
- Who owns the bottom, and do we need a letter of consent?
- Does the design need a seafloor (benthic) survey, and can it be done in the next window?
- Will the lift attach to the seawall cap? Who certifies the cap for the load?
- Which approvals and surveys does your price include?
- Do you carry federal longshore coverage? Monroe County’s Work Over the Water notice warns the owner may be liable otherwise. Monroe Work Over the Water notice
Local detail: Marathon, Key Colony Beach and Long Key and Layton.
Keys dock and boat lift questions
How big can a dock be without a state permit in the Keys?
On a dredged canal, up to 1,000 square feet can qualify for the state exemption. On open water, the limit is 500 square feet. F.S. 403.813 County and sanctuary rules still apply.
Do I need a seagrass survey for my dock?
Often on open water. Marathon requires a seafloor (benthic) survey along open water, and the county requires one to show whether seagrass or hardbottom is present. Marathon dock checklist Monroe County code 118-12(m)(6)
Can I add a second dock?
Marathon and Key Colony Beach allow one dock per single-family lot. Marathon code 104.64 KCB Code 5-35 Ask your permit office elsewhere.
Show sourcesHide sources
- Rule 62-302.700, F.A.C. (Special Protection, Outstanding Florida Waters)Source reviewed 2026-10-28
- Rule 62-330.051, F.A.C. (Exempt Activities)Source reviewed 2026-10-28
- Section 403.813, Florida Statutes (2026)Source reviewed 2026-10-28
- Monroe County Land Development Code, Chapter 118 - Environmental ProtectionSource reviewed 2026-10-28
- Requirements to Obtain a Dock, Boat Lift, Mooring Piles or Swim/Observation Platform PermitSource reviewed 2026-10-28
- Rule 18-21.005, F.A.C. (Forms of Authorization)Source reviewed 2026-10-28
- SED Marathon OfficeSource reviewed 2026-10-28
- Sovereign Submerged Lands: Proprietary Authority versus Regulatory AuthoritySource reviewed 2026-10-23
- Comprehensive Plan Amendment Package (Ord. No. 2022-11-01), adopted June 1, 2023Source reviewed 2026-10-28
- LDR Sec. 108.20 Nonconforming Docks And Shoreline Stabilization StructuresSource reviewed 2026-10-28
- Code of Ordinances Ch. 5, Art. III Marine Construction and Improvements, Docking of BoatsSource reviewed 2026-10-28
- ERP e-PermittingSource reviewed 2026-10-28
- Dock Length Special Exception ApplicationSource reviewed 2026-10-28
- Code of Ordinances, Subpart B Land Development Regulations, Ch. 110 Resource Protection, Art. IV Coastal ResourcesSource reviewed 2026-10-28
- Building Department - About UsSource reviewed 2026-10-28
- LDR Sec. 104.64 Waterfront Walkways And DocksSource reviewed 2026-10-28
- BuildingSource reviewed 2026-10-28
- Building Department and Code EnforcementSource reviewed 2026-10-28
- Contact UsSource reviewed 2026-10-28
- Checklist for Dock Permit ApplicationSource reviewed 2026-10-28
- Resource Assessment Survey Protocols for Nearshore Construction ProjectsSource reviewed 2026-10-28
- Nearshore Construction PermitsSource reviewed 2026-10-28
- PermitsSource reviewed 2026-10-28
- Jacksonville District Regulatory Office LocationsSource reviewed 2026-10-28
- Regional General Permit SAJ-82Source reviewed 2026-10-28
- US Army Corps of Engineers announces publication of 2026 nationwide permitsSource reviewed 2026-10-23
- Coupon Bight Aquatic PreserveSource reviewed 2026-10-28
- Rule 18-20.004, F.A.C.Source reviewed 2026-10-28
- Building Fees (Code Sec. 14-1 and 14-2)Source reviewed 2026-10-28
- Resolution 2025-73, Exhibit A Permit Fee ScheduleSource reviewed 2026-10-28
- Resolution No. 2026-01 (Fee Schedule for Building Department Permits and Services)Source reviewed 2026-10-28
- Resolution No. 277-2025 (Building Department permitting fee schedule)Source reviewed 2026-10-28
- Work Over the Water NoticeSource reviewed 2026-10-28