A few days before we could start the “real” work, we had already started dredging the upper and lower head of the Evergem lock. Because the government wanted to keep the lock in service until the last minute, we had to carry out our diving work in a narrow time window.
And then we could begin. Early in the morning we started placing huge steel bulkheads in the slots. Each bulkhead weighed over 35 tonnes and was about 22 metres long. They were brought to the site by special transport and taken over by a floating crane. Slowly, using guide ropes, each bulkhead was brought into position and very carefully lowered into the slots.
Our divers checked whether the bulkheads fitted well in the slots and made an exact connection with the floor or the previous bulkhead. Because everything was carefully cleaned and each bulkhead was fitted with an extra sealing system, there were no problems. Each bulkhead was additionally secured with large steel wedges placed by the divers. The pumps were started immediately after the last bulkhead was placed. More than 55,000 m³ of water had to be evacuated and the sooner the better.
The last bulkhead was placed in the darkness and when the sun came up people could already walk on the floor of the lock. The contractor had agreed with the authorities that the lock would not be emptied until all the fishes had been transferred from the lock to the canal. This produced some amusing moments: workers with long boots and large fishnets chasing the last fish to give them freedom in the canal.
Meanwhile, our divers set to work sealing the last leaks. During the day, the lock was sufficiently empty and dry for the real work to begin. In four weeks, the Evergem lock received six completely overhauled lockdoors that will last for decades.
The last lockdoor had only just been tested and delivered when we started on the diving works to remove all the bulkheads and the sealing material. After a long day, the lock was under water again and the contractor could hand it over to our government for use.
Another satisfied customer!