Between our first inland stop at Watten and our second at Béthune lies 48 km of the Grand Gabarit, the main commercial navigational artery in this region of Europe. Le Grand Gabarit, also known as the Canal Dunkerque-Escaut, is a 189 kilometer-long linked sequence of large waterways. It is the water equivalent of a superhighway. This day, we traveled a portion of le Grand Gabarit that included sections of the River Aa, the Canal de Neuffossé, and the Canal de Aire. We also passed through two locks. But saying that there are just two locks does not give the full story.
Locks on commercial waterways are generally large. Indeed, the locks on the Grand Gabarit are designed to fit barges up to 11 meters wide and 143 meters long. (That’s 36 feet by 469 feet if you don’t speak metric.). Inside these locks, Wanderlust is tiny. She takes up only about 5% of the available water surface area. By comparison, Wanderlust inside the far more common French and Belgian Freycinet Gauge locks occupies roughly 42% of the available surface area.
Besides being wide and long, locks on commercial waterways are generally deep. The first lock of the day, Ecluse Flandres, is just less than four meters deep. Two kilometers past Flandres, the second lock of the day, les Fontinettes, is much deeper.
The Fontinettes lock was constructed to bypass a nearby boat lift as part of the work to enable the use of the Grand Gabarit by very large commercial barges. I had casually noticed Fontinettes’ 13.13 m rise in our Fluviacarte guide but hadn’t thought much about it until we rounded the last bend of the waterway. There, directly ahead of us, stood a massive vertical four story high concrete wall with a gate at the bottom. On the side, the lock’s lights were red. We would need to wait mid-stream for the gate at the bottom to open.
Eventually, the lower guillotine-style gate raised trailing backlit streams of water. After the signal lights changed to green we entered slowly. As we passed through the gate Wanderlust was washed by rivulets of water.
Inside, the vertically walled chamber of the lock is nearly 500 feet long and over 43 feet deep. It is a deep dark manmade cavern. On the wall we found a pair of floating bollards, tied off, and waited for the lock cycle to commence.
There’s something ominous and intimidating about being at the bottom of such a deep lock. But what we recall most about the experience is the sound. The Fontinettes lock has eight floating bollards. These bollards are designed to rise and drop with the water level providing an easy way to secure boats and hold them in place against the moving water. Floating bollards move on their tracks inside a slot on the lock wall. Poorly lubricated, the floats move independently in spurts. Each surge upward produces a high-pitched metallic squeal as metal scrapes against metal. Sounds from all eight of the bollards resonate around the concrete walls of the concrete chamber. The result is an eerie otherworldly noise. It is something you might expect to hear in a video game or a movie soundtrack but not in real life.
A huge amount of water passes through the Fontinettes lock during a cycle. Based on the dimensions, a single lock cycle uses over six million gallons water. That’s roughly the amount of water that an average resident of Los Angeles California uses in a lifetime.
When we cycled through, the Angeleno’s lifetime of water was used to lift just two boats. It seems like a waste but it is not that simple. The water from the lock continues down the waterway. It will be used over and over again until it eventually reaches the sea.
Wanderlust, on the other hand, would head in the opposite direction. Against the imperceptible water flow we were moving slowly inland. Our destination was in Burgundy. Auxerre France, our goal, would take us nearly eight weeks to reach.
Waterways traveled: L’Aa, canal de Neuffossé, canal de Aire; 48 km, 2 locks