If a dam is constructed pursuant to an agreement concluded under the authorization granted by section 277d–13 of this title, its operation for conservation and release of United States share of waters shall be integrated with other United States water conservation activities on the Rio Grande below Fort Quitman, Texas, in such manner as to provide the maximum feasible amount of water for beneficial use in the United States with the understandings that (a) releases of United States share of waters from said dam for domestic, municipal, industrial, and irrigation uses in the United States shall be made pursuant to order by the appropriate authority or authorities of the State of Texas, and (b) the State of Texas having stipulated that the amount of water that will be available for use in the United States below Falcon Dam after the proposed dam is placed in operation will be not less than the amount available under existing conditions of river development, and to carry out such understandings and said stipulation the conservation storage of said dam shall be used, and it shall be the exclusive responsibility of the appropriate authority or authorities of said State to distribute available United States share of waters of the Rio Grande in such manner as will comply with said stipulation.