Section 18 Before giving notice of construction of works, plans to be prepared and deposited in the office of the commissioners.

Before giving notice of their intention to construct any work of which by this or the special Act they are required to give notice, the commissioners shall cause plans of the intended work to be made, under the direction of their surveyor, on a scale not less for a horizontal plan than one inch to eighty-eight feet, and for a vertical section not less than one inch to two feet, and, in the case of a sewer, showing the depth of such sewer below the surface of the ground; and such plans shall be deposited in the office of the commissioners, or some other convenient place appointed for that purpose, and shall be open at all reasonable hours for the inspection of all persons interested therein, during the time for which such notice is required to be given.