Locks on Europe’s commercial waterways are generally large. Indeed, the locks on the Grand Gabarit, northern France’s barge superhighway, are designed to fit barges up to 36 feet wide and 469 feet long. Aside from being wide and long, locks on commercial waterways are often deep. Particularly deep is les Fontinettes, an ecluse on the Grand Gabarit near Saint Omer.
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. Barges passing though the Fontinettes lock gain or lose 43 feet of elevation. From below, les Fontinettes is a massive vertical four story high concrete wall that rises abruptly from the water. At the bottom is a guillotine-style gate that lifts upward to let boats in and out. On the inside at the bottom, the lock is as a deep dark manmade cavern.
There’s something ominous and intimidating about being at the bottom of such a deep lock. But what we recall most about being there is the sound. Les Fontinettes uses floating bollards that are designed to rise and drop with the water level. These bollards move up and down on tracks anchored inside slots on the walls making it easier to hold a boat in place. Difficult to lubricate, each of the eight 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 floating bollards resonate around the concrete walls of the chamber. The result is an eerie otherworldly sound. 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 upon 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. 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.