(a) District bonds, including revenue bonds, that are not payable wholly from ad valorem taxes may be additionally secured, at the board's discretion, by a deed of trust or mortgage lien on the district's physical property and on all franchises, easements, water rights and appropriation permits, leases, and contracts and rights appurtenant to the property, vesting in the trustee power to:
(1) sell the property for the payment of the debt;
(2) operate the property; and
(3) take other action to further secure the bonds.
(b) A purchaser under a sale under the deed of trust lien, if one is given:
(1) is the absolute owner of the property, facilities, and rights purchased; and
(2) is entitled to maintain and operate the property, facilities, and rights.