The “emergency water supply fund” is created in the state treasury. Expenditures from this fund shall be made upon order of the state board of finance when the board determines that an emergency exists requiring the expenditure in order to provide an adequate and safe drinking water supply for residents of any community of less than 5,000 population in New Mexico using a drinking water supply system in common. Disbursements from the fund shall be upon vouchers signed by the secretary of finance and administration or his authorized representative.