Section 40

Before the Corporation proceeds to open or break up any street, bridge, sewer, drain or tunnel, the Corporation shall give to the persons under whose control or management the same may be, or to their officer, notice in writing of its intention, not less than seven clear days before beginning such work, except in cases of emergency arising from defects in any of the supply lines or other works, and then so soon as is possible after the beginning of the work, or after the necessity for the same shall have arisen.