Wood rot. That is why the top of the Boaz bridge in the center of Meppel collapsed in February. A passer-by fell, but after an investigation in the hospital it turned out that there was ‘no reason for medical care’.
The municipality of Meppel has commissioned an independent agency to investigate the cause of the collapse of the wooden bridge. That turns out to be wood rot. And the wood rot is caused by fungi. There was wood rot on the beams on both sides of the bridge.
“This occurs with a long-term high wood moisture content of more than 20 percent,” is the conclusion of the study. A protective layer on the wood seems to be the culprit. Moisture that has entered the wood through cracks could not escape through the protective layer. As a result, there was a constant high ‘wood moisture content’.
The bridge dates from 1992. “When the bridge was built, applying a protective layer was considered to extend its lifespan”, the researchers write. However: “Over time it has become apparent that this can also backfire.” Just like with the Boaz Bridge.
The bridge is now passable again for cyclists and pedestrians. The entire top of the bridge has been removed for this purpose.
However, the bridge cannot open now. This means that boats cannot leave or enter the Meppel canal. This is not a problem for the boats that are now moored there, as they have a permanent berth.
It will be a problem in a month. Then is the Grachtenfestival and the Meppel canals are traditionally full of historic boats. The municipality has a solution for that. The bridge deck will be removed on May 25. Cyclists and pedestrians then have to cross a small bridge to cross the canal.