§ 7. The commission, and any member thereof when directed by the
commission, may make any investigation which the commission may deem
necessary to enable it effectually to carry out the provisions of this
act, and for that purpose the commission, or such member, may take and
hear proofs and testimony and compel the attendance of witnesses and the
production of books, papers, records and documents, including public
records. The commission and its authorized agents may enter upon any
lands as in its judgment may be necessary for the purpose of making
surveys and examinations to accomplish any purpose authorized by this
act, the district being liable for actual damage done.