219. The Board may, by notice in writing, require the owner or any person having the control of any source of public water-supply which is used for drinking purposes- (a) to keep the same in good order and to clear it from time to time of silt, refuse and decaying vegetation, or (b) to protect the same from contamination in such manner as the Board may direct, or (c) if the water therein is proved to the satisfaction of the Board to be unfit for drinking purposes, to take such measures as may be specified in the notice to prevent the public from having access to or using such water: Provided that, in the case of well, such person as aforesaid may, instead of complying with the notice, signify in writing his desire to be relieved of all responsibility for the proper maintenance of the well and his readiness to place it under the control and supervision of the Board for the use of the public, and, if he does so, he shall not be bound to carry out the requisition, and the Board shall undertake the control and supervision of the well.