1. In all counties except counties of the first classification which have a charter form of government and which contain all or any portion of a city with a population of three hundred fifty thousand or more inhabitants, the governing body of the county, by resolution, order, or ordinance, shall appoint five trustees, the majority of whom shall reside within the boundaries of the district. In the event the district extends into any county bordering the county in which the greater portion of the district lies, the presiding commissioner or other chief executive officer of the adjoining county shall be an additional member of the appointed board of trustees. The trustees may be paid reasonable compensation by the district for their services; except that, any compensation schedule shall be approved by resolution of the board of trustees. The board of trustees shall be responsible for the control and operation of the sewer district. The term of each board member shall be five years; except that, members of the governing body of the county sitting upon the board shall not serve beyond the expiration of their term as members of such governing body of the county. The first board of trustees shall be appointed for terms ranging from one to five years so as to establish one vacancy per year thereafter. If the governing body of the county with the right of appointment under this section^* fails to appoint a trustee to fill a vacancy on the board within sixty days after receiving written notice from the common sewer district of the existence of such vacancy, then the vacancy may be filled by a majority of the remaining members then in office of the board of trustees of such common sewer district. The trustees may be paid reasonable compensation by the district for their services; except that, any compensation schedule shall be approved by resolution, order, or ordinance of the governing body of the county. Any and all expenses incurred in the performance of their duties shall be reimbursed by the district. The board of trustees shall have the power to employ and fix the compensation of such staff as may be necessary to discharge the business and purposes of the district, including clerks, attorneys, administrative assistants, and any other necessary personnel. The board of trustees shall select a treasurer, who may be either a member of the board of trustees or another qualified individual. The treasurer selected by the board shall give such bond as may be required by the board of trustees. The board of trustees shall appoint the sewer engineer for the county in which the greater part of the district lies as chief engineer for the district, and the sewer engineer shall have the same powers, responsibilities and duties in regard to planning, construction and maintenance of the sewers, and treatment facilities of the district as he now has by virtue of law in regard to the sewer facilities within the county for which he is elected. If there is no sewer engineer in the county in which the greater part of the district lies, the board of trustees may employ a registered professional engineer as chief engineer for the district under such terms and conditions as may be necessary to discharge the business and purposes of the district. The provisions of this subsection shall not apply to any county of the first classification which has a charter form of government and which contains all or any portion of a city with a population of three hundred fifty thousand or more inhabitants.

2. In any county of the first classification which has a charter form of government and which contains all or any portion of a city with a population of three hundred fifty thousand or more inhabitants, and in any county of the first classification without a charter form of government and which has a population of more than sixty-three thousand seven hundred but less than seventy-five thousand, there shall be a ten-member board of trustees to consist of the county executive, the mayors of the five cities constituting the largest users by flow during the previous fiscal year, the mayors of three cities which are not among the five largest users and who are members of the advisory board of the district established pursuant to section 204.310, and one member of the county legislature to be appointed by the county executive, with the concurrence of the county legislature. If the county executive does not appoint such members of the county legislature to the board of trustees within sixty days, the county legislature shall make the appointments. The advisory board members shall be appointed annually by the advisory board. In the event the district extends into any county bordering the county in which the greater portion of the district lies, the number of members on the board of trustees shall be increased to a total of eleven and the presiding commissioner or county executive of the adjoining county shall be an additional member of the board of trustees. The trustees shall receive no compensation for their services, but may be compensated for their reasonable expenses normally incurred in the performance of their duties. The board of trustees may employ and fix the compensation of such staff as may be necessary to discharge the business and purposes of the district, including clerks, attorneys, administrative assistants, and any other necessary personnel. The board of trustees may employ and fix the duties and compensation of an administrator for the district. The administrator shall be the chief executive officer of the district subject to the supervision and direction of the board of trustees and shall exercise the powers, responsibilities and duties heretofore exercised by the chief engineer prior to September 28, 1983. The administrator of the district may, with the approval of the board of trustees, retain consulting engineers for the district under such terms and conditions as may be necessary to discharge the business and purposes of the district. The provisions of this subsection shall only apply to counties of the first classification which have a charter form of government and which contain all or any portion of a city with a population of three hundred fifty thousand or more inhabitants.