Yesterday we scootered about 4.5 miles around Burlington Bay in Lake Champlain, visited three shipwrecks, and surfaced 3 hours and 50 minutes later. I was cold and very thirsty but the dive was a success. Skipping the heated vest was definitely a bad idea, even in 53 degree water. Although to be fair I could have just worn thicker undergarements.
The dive plan started the way all bad ideas start: I looked at a nautical chart and said, “You know, I wonder if we could scooter to these wrecks from shore?” After a few beers and some uncareful planning and exploration, we had our answer. While these wrecks are not next to each other, one sits right next to the Burlington breakwater, and the other two just so happen to lie near the city’s municipal water intake pipes. The General Butler, the O.J. Walker and the Horse Ferry are all part of the Lake Champlain Underwater Historic Preserves. Most people dive them one at a time, like sensible normal adults however I wanted to hit all three in one dive, from shore, on DPVs.
I jokingly named the dive “Three Wrecks and a Pipe Dream” since most of the route follows the city’s water intake pipes, and thinking we could finish in under three hours turned out to be exactly that, a pipe dream.
Scott and Jessica joined me for the dive. What better way for Jessica to take her brand-new Seacraft Future 1000 on its maiden inaugural voyage? I suspect most people would head down to the quarry first. There’s probably some irony in the fact that Jessica’s first DPV dive with this new scooter will probably cover more distance than 90% of scooter divers ever intend to travel.
In all seriousness, we talked through multiple contingency plans in case a scooter failed. I won’t get into too many details, but a few weeks earlier I’d learned I could tow someone back from our farthest point with battery to spare, so I wasn’t overly concerned about an untested scooter. Because I did this exact fucking scenario two weeks earlier. 🙂
How we got here
We didn’t wake up one morning and decide to link three wrecks. We spent 2020-2021 diving each one on its own first to prove we could actually find them. These are very easy beginner-friendly wrecks but turning them into shore dives takes on a whole other level of fun and planning.
- The General Butler We started with the easy one. The Butler sits right off the south end of the breakwater, so the navigation amounts to point scooter towards breakwater and then “follow the giant pile of rocks.” Someone had already run a line from the breakwater to the wreck, so I can’t take credit for that.
- The intake pipes. Next came some quality time with the nautical chart, where I noticed three water intake pipes running out from downtown Burlington. Phase one of the project was a scouting mission. We had to confirm we could find the pipes, and that they stayed visible for the entire dive and didn’t just disappear into the silt halfway out.
My buddy Tom and I drove up one late-fall day and were greeted by 30+ knot winds, huge waves, and whitecaps in the harbor. We proceeded to do what any two sensible people would do in this situation, we went diving. Luckily, the breakwater gives you some shelter from the waves. Our exit, as I recall, was less than graceful. - The O.J. Walker (October 2021). With the pipes verified, could we actually find the wrecks from there? My buddy Gary provided accurate GPS coordinates for the end of the southern intake pipe, and from those I worked out a compass heading and distance to the wreck. My buddy John humored me and came along, though I’m pretty sure he rated our chances of finding the wreck somewhere between low and zero.
Running about 900 feet of line across a featureless mud bottom, with nothing to judge your position by, is a great way to find out whether you actually trust your math and your compass. Newsflash: we ran straight into the stern of the wreck. I wish I still had the GoPro footage, because you can hear me yelling through my regulator that we’d found it. John and I then went back over several dives and added more silt stakes and improved the guideline. - The Horse Ferry (November 2021). By comparison, this one was super easy. It sits only about ~50 to 75 feet from the northern intake pipe, so the hardest part was not overshooting the wreck. You can the sidescan image from Gary showing both the wreck and the intake pipe.
John, Pascal and I did this dive. While the distance is longer than the other two dives, it is shallower and the navigation proved much simpler. You can almost see the wreck on the left (southern side) of the intake pipe. John and Pascal both almost ran out of battery on their scooters (Blacktips with 12ah DeWalts) but we made it to shore without having to tow anyone and plenty of gas to spare.
Once each wreck was a known and repeatable dive, the obvious next question was: can we hit all three wrecks at once? That’s the kind of question that should come with a warning label. Don’t do this dive unless you are confident in your scooter burntime.
On those earlier dives I was using a Dive Xtras Blacktip, a scooter world-famous for its reliability in roughly the same way McDonald’s is famous for gourmet food and fine dining. Sooner or later, every Blacktip owner inevitably takes the tow of shame, leaving plenty of time to reevaluate their poor life choices.
In all seriousness, the Blacktip is a great entry-level scooter. It has some caveats, but after a few modifications and a custom 20ah (720 Wh) battery upgrade, mine has treated me well. I own three of them; I enjoy them very much but I very much understand their limitations. This should go without saying but there is an obvious fucking difference between a $2000 scooter and a $10,000 scooter if you aren’t aware. I have asked a lot out of these little scooters.
Unfortunately, the Blacktip doesn’t have the range for a dive like this, even with the bigger battery. For years, my buddies on their Seacrafts, Genesis and Suex scooters waited, not very patiently, for me to upgrade to a “big kid” scooter. Earlier this year I finally caved and bought a Suex Goldfinder XJ. It’s a great scooter. I’d already put plenty of trigger time on the older Suex XJTs, so I knew going in that I’d like it.
For keeping a heading I have Perdix mounted on the scooter with a compass calibrated and declination set to -14. Because my memory sucks, I used blue painters tape to write some important headings and timings on my scooter. It’s much quicker than pulling out wetnotes for referencing.
The Route
The loop starts and ends at Perkins Pier and uses the Burlington breakwater and the city’s water intake pipes for navigation. Burlington kindly laid three water intake pipes across the bottom of the bay north of the breakwater. We use 2 of these intake pipes for navigation, essentially treating them as a permanent guideline to the OJ Walker and Horse Ferry wrecks.
- Perkins Pier to the General Butler. Out to the breakwater and around its south end to the Butler, this canal boat sank here in 1876 after its captain and crew jumped onto the breakwater.
- North along the outside of the breakwater. Through broke down rock piles and zig-zags that were clearly designed by someone who doesn’t believe in straight lines.
- West along the southern intake pipe. From the North Breakwater light out to the end of the pipe. The southern most intake pipe is approximately 150ft from the end of the breakwater
- Off the pipe to the O.J. Walker. A permanent guideline runs most of the way to the wreck. We cut the line back purposely quite a bit so nobody would accidently follow it.
- North across open water to the northern intake pipe, then west along it to the Horse Ferry. This part is easy, just take a heading and aim North. You cannot miss the intake pipe.
- Home. East along the northern pipe, a cut south to the southern pipe, then down the inside of the breakwater to Perkins Pier. We deliberately followed the northern pipe back toward shore for about 1,500 to 2,000 feet before cutting south, so there was no chance of overshooting the southern pipe.
The dive plan
On paper the loop was 22,704ft (4.3 miles) and ~2 hours 50 minutes, at 150 feet per minute with 4-5 minutes on each wreck. I think our actual distance was probably closer to ~4.5-5 miles based on our timing. These distances are estimated but some of them come from previous dives towing a flag with a GPS with Navionics.
| # | Leg | Estimated Distance (ft) | Heading (magnetic) | Planned time |
| 1 | Perkins Pier to the General Butler | 3,070 | ~279° to the breakwater | 21 min + 5 on the wreck |
| 2 | Outside of the breakwater, north to the North Breakwater light | 4,160 | Follow the zig-zags | 28 min |
| 3 | Southern pipe west to its end | 2,640 | ~283° along the pipe | 18 min |
| 4 | Pipe end to the O.J. Walker and back | 1,410 | 238° out, 058° back | 9 min + 5 on the wreck |
| 5 | Pipe end north to the northern pipe | 1,370 | 014° | 9 min |
| 6 | Northern pipe west to the Horse Ferry | 890 | ~298° along the pipe | 6 min + 5 on the wreck |
| 7 | Northern pipe east to its midpoint | ~1,500-2000 | ~121° along the pipe | 12 min |
| 8 | South to the southern pipe, then east to the breakwater | 1,840 | 194°, then ~101° | 13 min |
| 9 | Inside of the breakwater back to Perkins Pier | 4,340 | Follow the zig-zags, then ~106° to the pier | 29 min |
Most of the navigation is following a breakwater or an intake pipe which makes it relatively straight forward but there are still plenty of ways you can fuck it up, especially if visibility is poor.
The three open-water legs are short. You need to trust your compass and timings.
The average depth for the entire works out to about 40 (technically 34) feet, with a maximum of about 70 feet just before the O.J. Walker.
Gas planning, or: Should I cheat and use a rebreather? The answer is no.
I carried about ~300 cubic feet of gas. The plan called for 184 to 221 depending on runtime/sac-rate.
| Cylinder | Gas (cu/ft) |
| Double LP85s at 3,600 psi | ~223cu/ft |
| AL72 stage at 3,300 psi | ~77 |
| Total | 300 |
Yes, an AL72 instead of the usual AL80. I like how they ride, and I’ll happily trade 6 cubic feet for not having a stage that tries to float my hip to the surface at the end of the dive.
At a 40foot average depth we’re at about 2.21 ATA, so gas use at depth is the surface rate times 2.21:
| SAC (cu ft/min) | Use at depth (cu ft/min) | Planned dive, 2 h 46 min | 3.5 hours |
| 0.5 | 1.105 | ~184 cu ft | ~232 cu ft |
| 0.6 | 1.326 | ~221 cu ft | ~278 cu ft |
The rule of thirds at 300 cu/ft gives us about 100 cu/ft to play with before hitting turn pressure. At a relaxed 0.5 SAC the dive plan fit inside thirds with about ~16 cu ft to spare. At 0.6, the plan dips into thirds, which is the gas-planning equivalent of “we’ll probably be perfectly fine, but we might also become a case study in Human Factors in Diving.”
The worst case we planned around was a scooter dying at the Horse Ferry, the farthest point from an exit. Towing out along the northern pipe to shore is about 5000 feet.
How it actually went
The real dive was probably closer to 4.5-5 miles and 3 hours 50 minutes, more than an hour longer than the plan. Everything else went exactly to plan: the navigation was spot on and we never broke thirds.
| Planned | Actual | |
| Distance | 4.3 miles (22,704ft) | ~4.5+ miles (~23,800 ft) |
| Runtime | 2 h 46 min | 3 h 50 min |
The estimated distance was about 5-15% off which I still think is within the margin of error. The segments along the intake pipes and across open water took almost exactly as long as the plan said they would. The time was about 40% over. Honestly, I had a feeling going in that our runtime estimate was not conservative enough.
The extra hour was probably because of a few things. The first was the breakwater and initial low visibility. The visibility close to shore was near zero until we got further out.
Also, following the zig-zagging breakwater low visibility definitely added time. The second was reels. The breakwater and the intake pipes are not one continuous guide lines, no matter how continuous they look on a chart. Wherever there was a gap we stopped and tied in a reel. 4 reels total. A short reel to mark our jump-off point on the breakwater, bridging the gap from the breakwater entrance, breakwater to intake pipe and finally, a reel to the OJ Walker.
Here is a collaborated timeline of events of the dive (based on Shearwater dive profile, my notes and the video time stamps from the Insta360. This gives us a very accurate timeline. I’m not going to lie; I used Claude AI and uploaded the dive profile and used it analyze the events based on my video time stamps and my own notes.
| Time | Runtime | What happened | Planned | Behind plan | Depth |
|---|---|---|---|---|---|
| 11:16 | 0:00 | Descend at Perkins Pier | 0:00 | – | 5 ft |
| 11:43 | 0:27 | Arrive at the General Butler | 0:21 | +6 min | 34 ft |
| 11:47 | 0:31 | Leave the Butler and head north along the outside of the breakwater | 0:26 | +5 min | 25–30 ft |
| 12:11 | 0:55 | Switch from stages to doubles | – | – | 27 ft |
| 12:23 | 1:07 | Reel across the breakwater entrance gap | 0:51 | +16 min | 35 ft |
| 12:36 | 1:20 | Reel from the North Breakwater light to the southern intake pipe | 0:54 | +26 min | 34 ft |
| 12:53 | 1:37 | End of the southern pipe; follow the guideline toward the O.J. Walker | 1:12 | +25 min | 49 ft |
| 13:00 | 1:43 | Arrive at the O.J. Walker (70 ft max depth just before) | 1:17 | +27 min | 48–70 ft |
| 13:06 | 1:50 | Leave the O.J. Walker, reeling back to the guideline | 1:22 | +28 min | 61 ft |
| 13:13 | 1:57 | Back at the end of the southern pipe: turn pressure, go/no-go | 1:26 | +31 min | 49 ft |
| 13:13 | 1:57 | Open-water compass leg north (014°) to the northern pipe | 1:26 | +31 min | 49 → 43 ft |
| 13:32 | 2:16 | Arrive at the Horse Ferry | 1:41 | +35 min | 42 ft |
| 13:36 | 2:20 | Leave the Horse Ferry, head east on the northern pipe | 1:46 | +34 min | 43 ft |
| 13:43 | 2:27 | Cut south to the southern pipe | 2:03 | +24 min | 43 → 48 ft |
| 14:13 | 2:57 | Reel from the southern pipe back to the breakwater | 2:14 | +43 min | 31 ft |
| 14:20 | 3:04 | Reel back across the entrance gap | 2:17 | +47 min | 36 ft |
| 14:23 | 3:07 | Follow the inside of the breakwater back toward Perkins Pier | 2:18 | +49 min | 15–30 ft |
| 15:04 | 3:48 | Surface at Perkins Pier | 2:45 | +64 min | 0 ft |
For the gas nerds: I breathed about 191 cu/ft over 230 minutes at a 34-foot average depth (2.0 ATA). That’s about 30 cu/ft from the AL72 stage (3300psi to 2000 psi) and about 161 cu ft from the LP85 doubles (3700 to 1100 psi).
Divide it out and the SAC for this dive comes to about 0.415 cu ft per minute. We carried about 300 cu/ft and used about 64% of it, so we finished inside thirds, with about 9 cu ft of margin and the stage still holding 2000 psi.
I’m sure I fucked up the math somewhere and someone will be along shortly to tell me.
We started the dives on stages. Scott and Jessica both had AL80s and I had AL72. Around 70 minutes in we switched over to doubles and never went back to the stages. Jessica also had double LP85s and Scott was our emergency bailout plan with double HP130s. I had orginally planned on breathing my stage all the way down and preserving backgas but Scott and Jessica wanted to use thirds so I just switched off when they did. We are pretty evenly matched on gas consumption.
Jessica and I hit turn pressure at almost exactly the same time, just after we left the O.J. Walker and got back to the end of the southern pipe. We were both sitting at ~2,500-2,600 psi. I have no idea what Scott was at, but he gave me the “okay” to keep going, and that was good enough for me.
We’d agreed beforehand that this was our go/no-go point for the Horse Ferry segment. If any of us had hit turn pressure any earlier, we’d have called it, skipped the Horse Ferry, and turned the dive. It all happened right as we were about to point the scooters north into open water for the compass leg to the Horse Ferry. Actually perfect timing because this was about the halfway point of the entire planned loop.
We’d also planned four places where we could abort the dive if anything went wrong, each with a short, known way back to shore:
- The General Butler: back the way we came, around the south end of the breakwater to Perkins Pier.
- The North Breakwater light: straight down the inside of the breakwater to the pier.
- The end of the southern pipe, after the O.J. Walker: east along the pipe, then inside the breakwater home.
- The Horse Ferry: east along the northern pipe to the shore by the water treatment plant.
A note about SAC rates and dive planning
I know some pedantic asshole is going to berate me in the comments for not planning with a much higher SAC rate and you would be absolutely right however a good friend once told me, “there is no fun in safety.” Please don’t follow my advice. Make your own stupid decisions.
All kidding aside, These dives are shallow, with an average around 35-40 feet, and there’s no decompression obligation. There are several planned exits along the route. The last resort is simply going straight up, which is something you can’t obviously do in a cave.
I also know my cold-water scootering SAC rate well. It hasnt changed. Averaged over many dives, it comes out to about 0.414 cu ft per minute. On this dive it came out to about 0.415, so my lungs are at least consistent, even if my runtime estimates aren’t based in reality. This isnt a bumble brag or anything, my wife breathes way less.
Lessons learned
The biggest lesson: plan for the time it takes to deal with the gaps.
- Budget for the slow bits. Pipes and open water ran exactly to plan. The breakwater in low visibility and the reel tie-ins added time.
- Distance and time estimates aren’t perfect. Our navigation and gas were right on. Only the estimated runtime was off, by 40%.
- Plan your exits before you need them. Three or four abort points made the loop feel like a series of short dive segments. There is no lesson here but it’s a good idea.
- Know your worst point. For us it was a dead scooter at the Horse Ferry. In an emergency we could scooter or swim to North Beach.
Final thoughts
Despite being cold, hungry and thirsty, I had an awesome time, and I’ll probably do this dive again next year. Next time I’m wearing the heated vest.
I also don’t think this loop can reasonably be done in under 3.5 hours. You’d need stellar visibility along the breakwater and need to be scootering much faster. We could consider adding more permanent guideline with silt stakes on future dives to avoid the reel portions but why make it easy for everyone? So if you try it, plan for the long version and enjoy the pipe dream.
Note: This is not a dive guide. The route and numbers are from our own planning and Navionics GPS data on NOAA chart 14785. Plan your own dives for your own team, training and gear.
