The rural water assistance fund is a special fund in the state treasury. The fund consists of:
(1) money directly appropriated to the board for a purpose of the fund;
(2) repayment of principal and interest from loans made from the fund not otherwise needed as a source of revenue pursuant to Section 17.9615(b);
(3) money transferred by the board from any sources available;
(4) interest earned on the investment of money in the fund and depository interest allocable to the fund;
(5) money transferred to the fund from the water assistance fund in accordance with Section 15.011(b), including proceeds from the sale of political subdivision bonds by the board to the Texas Water Resources Finance Authority that are deposited in the water assistance fund as provided by Section 17.0871;
(6) money from gifts, grants, or donations to the fund;
(7) money disbursed to the fund from the state water implementation fund for Texas as authorized by Section 15.434; and
(8) any other fees or sources of revenue that the legislature may dedicate for deposit to the fund.