Every October the snowbird fleet starts moving south out of the Chesapeake, and the Atlantic Intracoastal Waterway turns from a quiet commercial channel into a moving parade of trawlers, sailboats, and sportfishers bound for Florida and the Bahamas. Distance is the easy part of the planning. The roughly 1,200 miles from Norfolk to Key West break down into predictable daily runs. What decides whether the trip goes smoothly is water depth in a handful of fast-shoaling reaches and the operating schedules of the drawbridges that cross the route.
Both of those change from season to season. Anything printed about specific depths, including what follows here, should be treated as a starting point and checked against current notices before you commit to a reach.
Why Depth Is the Real Planning Problem
The U.S. Army Corps of Engineers is responsible for maintaining the Atlantic Intracoastal Waterway, and most of the route is authorized for a 12-foot channel. Authorization and funding are different things. Through the 2010s, maintenance dredging money was thin enough that some reaches shoaled well below project depth; in 2014 the Corps received no dredging funding for the waterway at all, according to BoatUS.
The picture has improved. For fiscal 2024, the Corps directed $48.5 million to an AIWW work plan across five states: about $5.3 million for Virginia, $26.6 million for North Carolina, $8.5 million for South Carolina, and $4 million each for Georgia and Florida. BoatUS reported in May 2026 that the Corps has had projects running in all five waterway states for nine consecutive years, and that the agency's overall budget approved by Congress in January was $10.44 billion. The Atlantic Intracoastal Waterway Association, the nonprofit that lobbies for maintenance funding, continues to push for more, because shoals return faster than a single dredging cycle can address them.
Reaches to Watch Heading South
South Carolina: Breach Inlet, Isle of Palms, and the cuts
Breach Inlet, near Charleston Harbor around the Isle of Palms stretch (roughly statute mile 460), is described by AIWA's executive director as the fastest-shoaling area in South Carolina, needing dredging every two to three years. The Corps removed about 700,000 cubic yards of sand there over the 2026 winter and spring, so the area should be in better shape this fall than it has been. Farther south, a Waterway Guide navigation alert reported a shoal at Watts Cut (around mile 503) carrying 6.6 feet at mean lower low water as of June 1, 2026, with the contributor expecting less water as the year progressed.
Georgia: big tides, thin reaches
Georgia has historically been the most difficult state for depth. The Corps' Savannah District awarded a maintenance dredging contract in 2026 covering reaches at Daufuskie (Beaufort County, South Carolina) and Isle of Hope (Chatham County, Georgia), with a scheduled end date in late summer 2026; we could not confirm whether that work is complete. Waterway Guide reported in August 2025 that Buttermilk Sound, where the South Altamaha River meets the waterway near mile 662, had shoaled from 7.0 to 4.9 feet MLLW. Georgia's large tidal range means many boats can carry these reaches on a rising tide, which is exactly why timing matters more here than anywhere else on the route.
Florida: the inlet crossings
The places where inlets cross the waterway are where sand moves fastest. At Jupiter Inlet (about mile 1004), the same August 2025 Waterway Guide report recorded a drop from 8.8 to 6.2 feet MLLW. The Jupiter Inlet District finished its 2026 sand-trap dredging inside the inlet in two phases, January–February and April. A separate federal contract awarded in September 2025 covers about 100,000 cubic yards of waterway maintenance in the cuts near Jupiter; its completion status was not confirmed at the time of writing. At Ponce de Leon Inlet (around mile 843), Waterway Guide has pointed cruisers to a bypass route that has carried better water than the main channel.
Where to Get Current Depth Information
The Coast Guard's Local Notices to Mariners, published by district through navcen.uscg.gov, are the official record of dredging operations, shoaling, discrepancies in aids to navigation, and bridge work. The Fifth District covers Virginia and North Carolina; the Seventh District covers South Carolina, Georgia, and Florida. Corps district offices (Norfolk, Wilmington, Charleston, Savannah, Jacksonville) post channel condition surveys for their reaches. Waterway Guide's navigation alerts and crowd-sourced track data in apps such as Aqua Map and Navionics fill the gaps between official surveys.
Two habits help. First, remember that survey depths are given at mean lower low water, so actual depth is that figure plus the tide at the time you pass. Plan the thinnest reaches for the rising half of the tide, so a soft grounding floats you off rather than leaves you. Second, when you meet a working dredge, hail the operator on VHF channel 13 or 16 and ask which side to pass. BoatUS notes that dredge crews will often lead a hesitant boat through, and that pipelines and equipment around the work site should be treated as slow, no-wake zones.
Bridges: Schedules, Rush Hours, and Clearance
Drawbridge operations on the waterway are governed by Coast Guard regulations in 33 CFR Part 117, and those schedules are amended more often than most cruisers realize. Changes come through formal rulemaking or through temporary deviations for construction, events, or traffic tests, and both are published in the Federal Register and the Local Notice to Mariners.
Fort Lauderdale is the clearest current example. Under a final rule effective in February 2026, the SE 17th Street (Brooks Memorial) Bridge at about mile 1065.9 opens only on the hour during weekday rush periods, 6:50 to 9:10 a.m. and 3:50 to 6:10 p.m., excluding federal holidays. Outside those windows it continues to open on the hour and half hour. In West Palm Beach, the Coast Guard has proposed coordinating openings of the Flagler Memorial, Royal Park, and Southern Boulevard bridges. Proposals like that one can change the timing of a whole day's run through a city, so read current regulations for each bridge on your route rather than relying on last season's notes.
Fixed bridges on the Atlantic route are generally built to about 65 feet of vertical clearance. The notable exception is the Julia Tuttle Causeway in Miami, at roughly 56 feet. Sailboats with taller rigs typically go outside, commonly from Port Everglades at Fort Lauderdale to Government Cut at Miami. Published clearances assume normal water levels; unusually high tides, storm surge, or heavy runoff reduce them, and the figure you compare against should include antennas and masthead instruments, not just the mast.
Putting the Run Together
A practical southbound plan starts before you leave the dock. Check your insurance policy's navigation limits; many policies tie coverage to a home cruising area, and moving south for the winter can put you outside it unless you have arranged an extension. Pull the current Local Notices for both Coast Guard districts and save the relevant Waterway Guide alerts for each problem reach. Mark the tide windows you need for Georgia and the inlet crossings, and list the bridges on each day's route with their current schedules.
Then leave margin. Shoals move, bridge tenders run behind, and fronts pin boats in place for days in November. The cruisers who arrive relaxed are rarely the fastest ones; they are the ones who built the plan around the reaches and bridges that actually set the pace, and who checked the notices again the night before each one.