1. For carrying out the surveys and examinations required by title 19 of this article, the department may enter upon any lands, structures and waters as in its judgment may be necessary, as provided by section 15-0305.

2. The department, its members, officers, employees and agents may enter upon any lands, structures and waters necessary for the purposes of title 19 of this article and may determine what rights in and to such property are to be acquired therein. If the owner of any property to be acquired, or on or over which an easement is needed for such improvement shall agree with the department upon the sum to be paid therefor, or for the right to use and occupy the same, or for any damages sustained, such sum shall be paid as part of the necessary expense of the project.

3. If the department cannot agree with the owners upon the compensation and damages to be paid for the property or easement to be acquired, the department shall proceed to take the title thereto or the required rights therein under the provisions of the eminent domain procedure law.

4. Whenever a construction project affects a ditch or channel which has been constructed and in use for twenty years and upwards such use and operation shall be conclusive evidence that a right of way therefor and all rights in the premises through which it passes, which are necessary and incident to the perpetual maintenance thereof, were duly obtained when such ditch or channel was constructed. All real property acquired by a drainage improvement district shall be exempt from taxation.