After a hiccup Friday morning, the 2013 shipping season is now officially underway in the Welland Canal.

The Top Hat ceremony went ahead as planned, but traffic in the canal was stopped after the Allanburg bridge was shut down for most of the morning after an oxygen tank was impaled in the bridge's counterweight.

St. Lawrence Seaway Authority Spokesperson Andrew Bogora says one ship was held up from passing through, which is considered a very modest impact.

He says as of this stage the canal will be moving quite smoothly.

As for what happened, Bogora says he can't divulge internal procedure, but they will be looking into the matter "quite thoroughly".