§ 250. Purpose. The board of supervisors of each county may establish, consolidate, or extend county water, water quality treatment, sewer, wastewater disposal, drainage or refuse districts (hereinafter referred to in this article as the "district") in the manner hereinafter provided:

1. For the purpose of developing or acquiring a supply of water for (a) wholesale distribution to other municipalities, districts or persons, corporate or otherwise, within the county water district, (b) retail distribution, except as hereinafter provided, or (c) both such wholesale and retail distribution;

1-a. For the purpose of (a) procuring by purchase, lease or other means and installing water quality treatment units or devices, if required; providing periodic testing and monitoring of raw and finished water from private wells in the district; monitoring, modifying, repairing, replacing, operation and maintenance, regenerating water quality treatment units and devices and the administering of the treatment and disposal of residuals generated in the operation of the district pursuant to rules and regulations adopted by the public health and health planning council under § 225 of the public health law; (b) assisting local, state and federal agencies and officials in efforts to establish causes of, and implement remedial measures to reduce water contamination and protect future water resources within the district; (c) conduct public meetings and issue an annual public report to members of the district on the operation, financial position and water quality condition of said district; provided, however, that with respect to any town in the county the board of supervisors shall first determine that such district or service will not be established or provided by such town.

2. For the purpose of (a) the conveyance from other municipalities and districts within the county of sewage, and treatment and disposal thereof, (b) collection, except as hereinafter provided, or (c) both such conveyance and such collection;

3. For the purpose of administration and planning (including educational programs), design, installation, construction, rehabilitation, replacement, operation and maintenance (including pumping and inspections), monitoring, residual treatment and disposal and regulation of private on-site wastewater disposal systems of such district;

4. For the purpose of drainage of storm water and other waters, either surface or subsurface, within the county;

4-a. For the purpose of effecting lake protection and rehabilitation, and any activities necessarily related thereto.

5. For the purpose of the collection and disposition of garbage, ashes, rubbish and other waste matter within the county.

6. A county district established hereunder may consist of two or more noncontiguous areas in which the water, sewer, wastewater disposal, drainage or refuse system (hereinafter referred to in this article as the "system") will be interrelated and interdependent, however, in Suffolk county the term "interrelated and interdependent" shall be deemed to mean that the noncontiguous areas must be within the county and have the same administrative head. However, a water quality treatment district established hereunder may consist of noncontiguous or contiguous benefited parcels of property and shall be created by a resolution of the county board of supervisors, upon petition after a public hearing.

7. Except in the county of Suffolk, no county district shall be established hereunder which shall consist wholly of territory within one city, within one village or within that portion of one town outside of a village.

8. Notwithstanding any other provision of law a sewer district may also exercise all the powers of a wastewater disposal district if the map and plan prepared pursuant to section two hundred fifty-three of this chapter, or amended pursuant to section two hundred fifty-three-b of this chapter, includes on-site wastewater disposal systems.