All sanitary districts organized under the provisions of this article shall proceed as rapidly as possible to provide sewers and a plant or plants for the treatment or purification of its sewage, which plant or plants shall be of suitable kind and sufficient capacity to properly treat and purify such sewage so as to conduce to the preservation of the public health, comfort and convenience and to render said sewage harmless, insofar as is reasonably possible, to animal, fish and plant life. Any violation of this proviso and any failure to observe and follow same, by any sanitary district organized under this article, is a misdemeanor on the part of the sanitary district and upon conviction, said sanitary district shall be punished by such fine as law and equity may require, and the trustees thereof may be removed from office as trustees of said sanitary district by an order of the court before whom the cause is heard. It is the duty of the division of environmental protection or the bureau of public health or other body having proper supervision of such matters, to enforce the foregoing provisions; and upon complaint of said office or bureau it is the duty of the attorney general or prosecuting attorney of the county in which such violation may occur, to institute and prosecute such cause by indictment or in the manner provided by law.