After an improvement district has been created, the board of township supervisors shall direct a competent engineer to prepare a report as to the general nature, purpose, and feasibility of the proposed improvement and an estimate of the probable cost of the work. The board of township supervisors shall provide thirty days’ written notice by first-class mail to each freeholder within the improvement district at the address shown on the records of the county treasurer and shall publish a notice in a legal newspaper published in the township or, if there is no such newspaper, then in the county’s official newspaper at least ten days prior to a special meeting for public disclosure of the findings of the engineer.