There may be created by each irrigation district or separate legal authority created pursuant to RCW 87.03.018 a fund to be known as the upgrading and improvement fund. The board of directors shall determine what portion of the annual revenue of the irrigation district or separate legal authority will be placed into its upgrading and improvement fund, including all or any part of the funds received by a district or separate legal authority from the sale, delivery, and distribution of electrical energy. Moneys from the upgrading and improvement fund may be used to modernize, improve, or upgrade irrigation and hydroelectric power facilities or to respond to an emergency affecting such facilities. The funds may also be used for licensing hydroelectric power facilities and for payment of capital improvements.