Mont. Code Ann. § 85-8-347

If there be no remonstrance or if the finding be in favor of the validity of the proceedings or after the report shall have been modified to conform to the findings, the court shall confirm the report. The order of confirmation shall be final and conclusive, the proposed work shall be established and authorized, and the proposed assessments approved and confirmed unless within 30 days an appeal be taken to the supreme court. The said order of confirmation shall also fix the commissioners' bond.