93. Every person who installs coffer dams and structures for the temporary diversion of a watercourse, such as a diversion canal, to dry all or part of the work area during the construction, improvement, repair or removal of a bridge or a culvert must, in situations other than those described in section 103, ensure that the coffer dams and diversion structures do not prevent the flow of fish during more than 5 days and that they limit the carrying of sediments into the watercourse. Where the period exceeds 5 days, the coffer dams and diversion structures must not reduce the width of the watercourse by more than 1/3. The width of the watercourse is measured at the level of the upper limit of the banks.
At the end of the work, the coffer dams must be removed and the diversion canal used during the diversion of the watercourse must be filled by restoring the vegetal cover.