Patents and water-right certificates which shall be issued after May 15, 1922, under the terms of subchapter XIV of this chapter, for lands lying within any irrigation district with which the United States shall have contracted, by which the irrigation district agrees to make the payment of all charges for the building of irrigation works and for operation and maintenance, shall not reserve to the United States a lien for the payment of such charges; and where such a lien shall have been reserved in any patent or water-right certificate issued under said subchapter, the Secretary of the Interior is empowered to release such lien in such manner and form as may be deemed effective; and the Secretary of the Interior is further empowered to release liens in favor of the United States contained in water-right applications and to assent to the release of liens to secure reimbursement of moneys due to the United States pursuant to water-right applications running in favor of the water users' association and contained in stock subscription contracts to such associations, when the lands covered by such liens shall be subject to assessment and levy for the collection of all moneys due and to become due to the United States by irrigation districts formed pursuant to State law and with which the United States shall have entered into contract therefor: Provided, That no such lien so reserved to the United States in any patent or water-right certificate shall be released until the owner of the land covered by the lien shall consent in writing to the assessment, levy, and collection by such irrigation district of taxes against said land for the payment to the United States of the contract obligation: Provided further, That before any lien is released under this section the Secretary of the Interior shall file a written report finding that the contracting irrigation district is legally organized under the laws of the State in which its lands are located, with full power to enter into the contract and to collect by assessment and levy against the lands of the district the amount of the contract obligation.