(b) No claim shall be made against the Government for compensation in respect of loss caused by the failure or stoppage of the water in a canal, by reason of any cause beyond the control of the Government, or of any repairs, alterations or additions to the canal, or of any measures taken for regulating the proper flow of water therein, or for maintaining the established course of irrigation which the canal-officer considers necessary; but the person suffering such loss shall be entitled to such remission of the ordinary charges payable for the use of the water as is authorized by the Government: