The canals may be closed once a year for effecting the necessary repairs to them on one month's notice of the intention so to close them being given; but whenever it becomes necessary to close the canals immediately owing to the failure of the supply of water in the river or to any unforeseen emergency, they may be closed without prior notice, or kept closed beyond the date fixed for re-opening, and no claim in such case by owners of vessels or others for compensation on account of detention shall be entertained.
