There are hereby authorized to be appropriated such sums (but not more than $10,804,000 for the acquisition of lands or interests in lands) as are necessary to carry out the purposes of this subchapter.

(Pub. L. 88–492, § 8, Aug. 27, 1964, 78 Stat. 610; Pub. L. 92–272, title I, § 101(7), Apr. 11, 1972, 86 Stat. 120.)