Scraping Barnacles

Posted by John

Normally, cleaning the hull would be just a regular maintenance item, but when you decide to do it yourself using scuba gear, and you haven’t dived in over twenty years, it might be worth a blog post of its own.

On our passage to Tonga we suspected that the hull needed cleaning. We had cleaned the waterline more than once in French Polynesia, and it already needed it again. But we hadn’t had the entire bottom cleaned since the two times we had it done in Mexico.

Most of the waterline cleanings have been done by Julie. Her technique involves straddling a pool noodle in the water, hanging onto a suction cup hull gripper, and working her way around the boat with a plastic scraper, scrubby pad and boot brush. My technique involves lying in the dinghy alongside the boat and reaching over the side to scrub the waterline. After a few feet of waterline scrubbing I tend to get lazy and may even doze off. My technique doesn’t work as well as Julie’s, but being in the water on the surface with my feet dangling down gives me the willies for some reason. Twenty-five years ago I was an avid scuba diver diving with sharks, barracuda and all manner of sea creatures big and small. Even though I never had fish nibbling my toes (I was “mouthed” by both a stingray and a cabezon) I still seem to have developed a fear of it, so I prefer my technique of waterline scrubbing, or at least making an attempt at it. It was while lying in the dinghy next to the boat that I reached under as far as I could and felt a solid surface of tiny barnacles on the bottom of our hull.

With visions of needing a hammer and chisel to chip thousands of barnacles off the hull keeping me awake at night, we started asking around. In the Mexican marinas, divers with hookah systems powered by electric air compressors from Home Depot came around looking for jobs all the time. Not so in Tonga. The recommended procedure here is to go around the corner to the boatyard in the next bay for a haul out and pressure wash. This required an appointment a week out and costs more than we wanted to spend, not to mention the hassle of the haul out itself and the toll that the pressure washing would take on what’s left of our bottom paint. We’re going to repaint in New Zealand so we don’t want to haul out before then if we don’t have to. We decided to scrape the barnacles ourselves.

We brought one complete set of scuba gear with us. All of it was sitting around in our garage at home and had not been used on a dive since 1996. We brought it along for that dire emergency when it would be necessary to untangle the prop or clear the engine water intake.

We found a dive operator in Neiafu willing to rent us two tanks, a buoyancy compensator vest, a regulator and gauges, and a weight belt for 50 pa’anga (about $25). We took our dinghy over to his shop along the waterfront and loaded it up before he went out for the day. He wanted it all back between 4:00 and 4:30 the same day. We had our own masks, fins and dive skins. Due to the damage barnacles can do to skin, I wanted to wear the 3mm wetsuit that I had also brought along. Of course, the last time I had worn it was when Julie and I went diving in Hawaii in 1996. With the rented gear we were all set, two of us could dive at the same time. Since Robyn had a painful thing going on in her ear canal and wasn’t going into the water, it would be Julie and me. What could possibly go wrong?

My wetsuit is a one-piece with a zipper up the back. I struggled to get my legs into it, finally succeeded, and then realized that my legs were in where the arms are supposed to go. Regardless, the suit was backwards anyway. Getting my legs out again was even harder than getting them in. By the time I got the suit on properly I was already exhausted. Getting old sucks.

The thought of diving from our own boat was kind of exciting, but I’ve never dived off a sailboat before, and our boat is certainly not the best design for getting into dive gear and then getting into the water. We decided we’d have to get geared up in the dinghy and get into the water from there. The dinghy is small. Dive gear is heavy and awkward. Just putting everything together was an exercise in thinking way back to a couple of decades ago. “Hey Robyn, do the hoses come out the top or the bottom?”

We finally got everything set up and ready. All we had to do was help each other get the tanks and weights on. I needed the weight belt to counteract the buoyancy of the wetsuit, and Julie put the few weights we brought from home into her BC pockets (her BC was designed for that). The problem was, since we had put our fins on already our feet were too big to move around in the dinghy. We were standing on each other, unable to move. I took my fins off again. Julie helped me get my tank and the weight belt on. She then hung her legs over the side of the dinghy and I helped her get her tank on. Then I sat on the edge and put my fins back on. Her feet were dangling outside, and my feet rested firmly inside on the dinghy floor. Then, with mask in place and breathing through the regulator, I gathered up all the hoses and gauges and held them against the weight belt buckle to keep it from popping open, put my other hand on my mask and regulator mouthpiece, and did a backwards roll into the water for the first time in more than twenty years. Just like riding a bike. It all came back instantly. Except that it wasn’t my gear and it didn’t fit properly, it was uncomfortable, and I was breathing way too fast.

We went up to the bow and I pulled myself down the anchor chain to the bottom. Hello fish, I’ve missed you. But I didn’t have enough weight. If I let go of the chain I floated right back up. Julie couldn’t stay down either. It’s really hard to accomplish anything underwater when you are too buoyant and it takes all your energy just fighting to stay down.

Rather than both of us working together at the same time, we decided to take Julie’s weights out of her pockets and put them on my belt. We could then trade off with the belt and take turns scraping. Of course, we took the extra weights and strung them onto the belt while we were in the water. My BC was a front-inflate, designed to roll you over face up, while Julie’s BC is a rear-inflate with weight pouches in the front. With neither of us having any weight at all except for the weight belt we were both struggling with and trying not to drop, we bobbed and floated all over the place. If we had dropped any weights, especially the entire weight belt, we’d have a rough time of getting down to the bottom to retrieve it.

Once we got the weights worked out, we scraped for what seemed like most of the day. Going over the entire underside of a 42-foot, full keel hull with a 5-inch scraper takes a long time. Some of the barnacles were holding on too tightly to just scrape off. They will have to wait for the haul out. The water clouded up with everything we were getting loose, including tiny crabs and krill. The bottom of our boat had become a little ecosystem. When working overhead, everything floated down into our faces. I kept bumping my head on all the barnacles that weren’t scraped yet (they hurt). Those guys in Mexico really earned the few pesos they were asking for.

When we were done, we inflated our BC’s and took them off so the tanks would float on the surface. I managed to get my fins off and into the dinghy without dropping them, then while Julie kept the tanks from floating away, I went up the boarding ladder and stepped into the dinghy. From there I could drag the tanks out of the water. We left everything in the dinghy and went up onto the boat to drink beer. When I took off the wetsuit it was a surprise to see how many little wiggling creatures had gotten inside of it. In a very short time it was 4 PM and we remembered we had to run everything back to the dive operator.

Completely exhausted, we slept well that night. And it felt good to have “gotten back into diving,” such as it was. Maybe now that we’ve broken the ice, and Robyn is recently certified, we can do some actual diving for fun before we get back home.

Those black branch-like things are barnacles trying to grab passing nutrients
I’m getting pretty tired at this point; the weight belt has slipped down and is not at all comfortable, and the bulge on my right ankle is because 26-year old Velcro isn’t holding anymore.
The heavy growth area at the bottom is the top of the rudder; the whole rudder looked like that when we started, and the little fish were hanging out in it