The cooperation and contract may be for any or all of the following purposes:
(a)
Construction, acquisition, purchase, extension, operation, or maintenance of works for irrigation, drainage, storage, flood control, generation and distribution of hydroelectric energy incidental thereto, or any of these.
(b)
A water supply.
(c)
Assumption as principal or guarantor of indebtedness to the state, the department, any other district, or the United States.
(d)
To carry out the terms of any contract between the district and the state, the department, any other district, or the United States.