To take over, by purchase, lease or by voluntary agreement, and to administer, any soil-conservation, water-conservation, flood-prevention, erosion-control or erosion-prevention project located within its boundaries, undertaken by the United States, or by this State or any of its agencies; to manage, as agent of the United States, with its consent, or of this State, with its consent, or of any of its agencies, any such project within its boundaries to act as agent if so desired and requested for the United States, or for this State or any of its agencies, in connection with the acquisition, construction, operation or administration of any such project within its boundaries; to accept donations, gifts and contributions in money, services, materials, or otherwise, from the United States, or from this State or any of its agencies, and from any other source, and to use or expend such district moneys, services, materials, or other contributions in carrying on its operations.