Any person having the right to use, sell, or dispose of water and engage in using, selling, or disposing of the same who has a surplus of water not used or sold or any person having a surplus of water and the right to sell and dispose of the same is required, upon the payment or tender to the person entitled thereto of an amount equal to the usual and customary rates per inch or cubic foot of water per second, to convey and deliver to the person the surplus of unsold water or so much thereof for which the payment or tender has been made and shall continue to convey and deliver the same weekly so long as the surplus of unused or unsold water exists and the payment or tender is made as aforesaid.
§ 85-2-415, MCA