The plans to be submitted to the sewerage authority shall be detailed plans, drawings, sections and specifications describing the position and manner in which, and the level at which, any specified work is proposed to be carried out and the position of all sewers of the sewerage authority within the limits of deviation for that work, and shall comprise detailed drawings of every alteration which the appropriate authority propose to make in any such sewers.

For the purpose of the preparation of the said plans the sewerage authority shall, on application by the appropriate authority, permit them to have access to plans in the possession of the sewerage authority and to any of their sewers.