The district may contract for:
(1) purchasing or selling raw or treated water;
(2) transporting, treating, or disposing of the district's domestic, industrial, or communal waste;
(3) transporting, treating, or disposing of domestic, industrial, or communal waste of others as provided by Chapter 30, Water Code;
(4) purchasing, leasing, using, managing, controlling, or operating a water treatment or distribution facility or a sewer collection and treatment facility, including all or part of a facility or system owned by another political subdivision; or
(5) planning, surveying, investigating, or preparing a report of any kind.