Planning the Great Loop with a tall boat

The first number every Great Loop boater learns is air draft: the height from the waterline to the highest point on the boat. The Loop has fixed bridges you can’t open, wait out or go around. If your boat is too tall for them, you’re not doing the Loop. Hot ’n Dirty is a tall boat, so this was the first problem we had to solve, before we even made an offer…our plan: modify or replace at considerable expense, yes more of the newer generation of BOAT dollars…as Nordhavn’s Dan Streech recently said, it’s not $1K anymore, it’s more like $10K. Arg!

Our numbers

Hot ’n Dirty is a 1986 DeFever 57 Yachtfisher: 57 feet long, 16 feet 6 inches wide, with a draft of about 4 feet 9 inches. Draft is no problem anywhere on the Loop…well, perhaps ‘no problem’ is not accurate, but certainly doable, and many have done it, both with and without damage…wish us luck!

Air draft is the problem. The listing said 23 feet 5 inches to the top of the radar, and the previous owner thought it was closer to 24 feet. That number has never been measured, so measuring it properly is on our survey checklist. The factory boat was designed with about 18 feet 5 inches of clearance; ours is taller because of what’s been added on top since. The original radar arch was removed by the previous owner, who owned her for 24 years. He had a custom aluminum top constructed, with the Garmin xHD 18” dome radar, Starlink and anchor light mounted on top…and we will likely be adding AIS.

The bridges that set the limit

These are the clearances Loopers plan around. Water levels change them by as much as a foot, and published figures vary between sources, so check current charts and the Great Loop association’s latest numbers before you go.

Where	Approximate clearance	What it means
Chicago, the fixed railroad bridge on the route to the Illinois River	About 19 feet 6 inches (some older sources say 19 feet 1 inch)	The hard limit. Every full-Loop boat must get under it.
Downtown Chicago River route	About 17 feet	Lower still; taller boats take the Calumet route instead.
Western Erie Canal	About 15 feet 6 inches	Too low for most trawlers.
Eastern Erie and the Oswego Canal	About 20 to 21 feet	The usual route to Lake Ontario for taller boats.
Trent-Severn Waterway	About 22 feet	Our route through Canada to Georgian Bay.
Champlain Canal	About 17 feet 5 inches at Lock C5 (raised for 2026)	Not on our route.

The rule we’re using: plan for the lowest published figure, then add margin for high water and waves. Our target is to get Hot ’n Dirty under 19 feet when lowered.

Our route

The plan starts and ends at our home port in the Tidewater area of Virginia. We’ll go north up the Chesapeake and the New Jersey coast to New York, up the Hudson River, west on the eastern Erie Canal, and north on the Oswego Canal to Lake Ontario. Then through the Trent-Severn Waterway to Georgian Bay and the North Channel, and down Lake Michigan to Chicago. From there, the inland rivers, with a side trip up the Cumberland to Nashville, and the Tennessee-Tombigbee Waterway to the Gulf. Then down Florida’s Gulf coast, around the Keys, and home up the Intracoastal Waterway. The Bahamas will be a trip of their own once we’re home.

The western Erie Canal is out for us at any height we can reach, so we turn north at Oswego. That’s the usual choice for taller boats. You can see a simple view of the route in our “Where are we” page.

What has to come down

The radar and anchor light are the highest points. A hinged or removable radar mount is the first fix we’re pricing; it’s the standard solution on boats like ours. Other DeFever owners have done the Loop with hinged radar arches, and one similar boat measured about 19 feet to the top of its hinged arch. Other options are electric, hydraulic and of course manual tops, potentially possible with modifications to what is there today, but it looks challenging.

After the radar and anchor light, the next tallest items are:

• VHF antennas, which need to simply be folded down, even though they are technically the highest point today.
• The flybridge top frame, which must lower, be refit, replaced or come off.

The goal is a top that can come down at the dock before the Chicago bridges and go back up afterward, without a crane or a yard, ideally…but we may have to investigate that as well.

There’s one conflict we still have to solve. Our refit plan puts six solar panels on the flybridge top. Whatever we do to lower the top has to work with the panels on it as well.

Fuel and range

Our boat has twin Caterpillar 3208 diesels. At about 8 to 9 knots, other owners of our model report burning 7 to 8 gallons an hour for both engines together. Above 12 knots, the burn climbs steeply as with any boat.

Fuel capacity is 1,500 gallons on this boat across 6 tanks. Using the lower number and about 7.4 gallons an hour, that’s roughly 160 hours, or about 1,300 nautical miles at 8.5 knots, before any reserve. Those are calculations, not measurements. We’ll check them against real fill-ups once we’re running a while.

On the Loop, range is rarely the limit. Fuel stops are frequent, and the longest gaps are on the rivers. We’ll plan for a generous reserve on those stretches.

Timing

Most boats take 9 to 11 months to do the Loop, covering about 50 miles on a travel day. We’ll take about two years. We’re both still working full time, so the boat stays put on workdays. It moves on weekends, the odd Friday afternoon, a few long weekends, and two weeks of vacation a year.

We’re also planning shorter days than most Loopers. We travel in daylight only, and on a weekend we can’t wait for better weather. So we’re planning on about 30 miles a day through the canals, 35 on the rivers, where commercial barges get the locks first, and 40 on open water and the Intracoastal Waterway. For a route of roughly 5,300 miles, that’s about 140 travel days.

Leg	Waters	Miles	When
1	North from Tidewater: the Chesapeake and the New Jersey coast to New York	420	May to mid-June 2027
2	The Hudson, the Erie Canal and the Oswego Canal	335	Mid-June to mid-July 2027
3	Canada and the Great Lakes, down Lake Michigan to Chicago	980	Mid-July to late September 2027
4	The rivers to Kentucky Lake, then up the Cumberland to Nashville	760	October to December 2027
	Winter in Nashville, then spring and summer on Kentucky and Barkley lakes		December 2027 to September 2028
5	Down the Tennessee River and the Tenn-Tom to the Gulf, then around the Keys	1,505	October 2028 to early March 2029
6	Home up the Intracoastal Waterway	1,000	March to May 2029

Three things set the calendar. The canals in New York and Canada are open only from May to October. We want to be off Lake Michigan before the fall storms, which is where our first year’s vacation goes. And we won’t travel in the hurricane zone, from the Gulf to the Carolinas, between June and November. So we’ll spend summer 2028 inland on the lakes, reach the Gulf after hurricane season ends, and be home before the next one starts. All the distances are estimates. We’ll replace them with our real numbers as we go.

What we still need to confirm

• Air draft, measured from the waterline to the highest part of the existing flybridge top.
• The height we can reach with the radar and antennas down, and how far the top has to come down.
• Our real fuel capacity and burn with how we will cruise the boat.

We’ll post our measurements here as soon as we have them.