Tex. Transportation Code § 22.072

(a) Two or more public agencies may enter into an agreement with each other for joint action under this chapter. Concurrent action by ordinance, resolution, or otherwise of the governing authorities of the participating public agencies constitutes joint action.

(b) A joint-action agreement must specify:

(1) its duration;

(2) the proportionate interest each public agency has in the property, facilities, and privileges involved;

(3) the proportion each public agency pays of:

(A) the preliminary costs and costs of acquiring, establishing, constructing, improving, and equipping the airport, air navigation facility, or airport hazard area; and

(B) the costs of maintaining, operating, regulating, and protecting the airport, air navigation facility, or airport hazard area; and

(4) any other terms required by this subchapter.

(c) A joint-action agreement may include:

(1) provisions for amending the agreement;

(2) conditions and methods of terminating the agreement;

(3) provisions for disposing of all or any of the property, facilities, and privileges jointly owned before or after all or part of the property, facilities, and privileges cease to be used for the purposes of this chapter or on termination of the agreement;

(4) provisions for distributing the proceeds received on disposal of the property, facilities, and privileges and any funds or other property jointly owned and undisposed of;

(5) provisions for assuming or paying any indebtedness arising from the joint venture that remains unpaid on the disposal of all assets or on termination of the agreement; and

(6) any other necessary or convenient provision.