Mississippi Code Title 49. Conservation and Ecology § 49-17-745

(1) The county authority shall have the power, duty and responsibility to exercise general supervision over the design, construction, operation and maintenance of water, wastewater and storm water systems.

(2) The county authority shall adopt rules and regulations regarding the design, construction or installation, operation and maintenance of water, wastewater and storm water systems.

(3) The county authority shall adopt rules and regulations regarding the use of decentralized treatment systems, individual on-site wastewater treatment systems and centralized wastewater treatment systems.

(4) The county authority shall adopt rules establishing performance standards for water, wastewater and storm water systems and the operation and maintenance of the same. Such rules and regulations shall include the implementation of a standard application form for the installation, operation and maintenance of such systems; application review; approval or denial procedures for any proposed system; inspection, monitoring and reporting guidelines; and enforcement procedures.

(6) Any system of any municipality, public agency or other persons which contracts with a county authority, shall be subject to the terms of that contract and the terms of this act.

(7) Notwithstanding the provisions of Section 51-39-1 et seq., the county authority shall have the full power to adopt rules and regulations and to construct, maintain and operate facilities for the control of storm water quality and quantity. In addition, the provisions of Section 51-33-1 et seq. relating to drainage districts and flood control districts do not apply to the county authority.

(8) The county authority may control and operate the local retail water, wastewater or storm water services and may provide or be responsible for direct servicing of those services to residences, businesses and individuals; however, the county authority shall not provide the same service in an area provided by a public utility or person holding a certificate of public convenience and necessity issued by the Mississippi Public Service Commission for the provision of such services in the certificated area.