Drainage District Annexation Vacated Due to Lack of Material Benefit to Landowners

April 10, 2024 | Jennifer Harrington

On March 27, 2024, the Iowa Court of Appeals affirmed the district court’s determination to vacate a drainage district annexation. Both courts found the required engineer’s annexation study did not meet the statutory burden to specify the material benefits to the proposed annexed land. The report had concluded that all lands in the watershed would be benefited by the improvement due to more reliable drainage, but the court found that the report needed to show that the soil quality would be improved. Since the report failed to do so, the annexation was vacated.


The Hamilton County Board of Supervisors (Board) are the trustees of Drainage District No. 71 (DD71). DD71 was established in 1908 to drain Mud Lake. In 2019, a landowner within DD71 petitioned the Board to clean and repair the main open ditch. The Board hired engineering firm Bolton & Menk (B&M). B&M estimated that the repairs would cost $2,457,800. B&M also recommended that additional land be annexed into DD71. An annexation study was conducted by a B&M engineer and their report recommended annexation of 30,538 acres into DD71, which is all acres in the Mud Lake watershed.

Public hearings were held. By the second hearing, objecting landowners had retained their own engineer and at the meeting presented an evaluation from him. The objecting landowners’ engineer found that there would be no material benefit to the proposed annexation lands. After the second hearing, the Board approved the proposed annexation. One hundred and twenty-five owners appealed the annexation to the district court.

After trial the district court reversed the Board’s decision and vacated the annexation. The court found that B&M’s engineer did not show the annexed lands would be materially benefitted from DD71. Further, the court found the objecting landowners’ engineer to be more persuasive than the B&M’s engineer. The Board appealed the district court’s decision.


The Court of Appeals affirmed the district court’s decision on the same grounds. On appeal, the Board argued the record showed the land proposed to be annexed is materially benefited by DD71. Iowa Code § 468.119(1) details the necessary procedure for drainage district annexation. Specifically, an engineer must make an annex survey that “specif[ies] the character of the benefits received.” B&M’s annexation report had a “conclusory and brief” statement that the annexed lands benefitted since they were upland of the DD71 open ditch.

The court examined a 1907 Iowa case, Zinser v. Bd. of Sup’rs, 114 N.W. 51, 56 (Iowa 1907), to find the correct legal test for determining if lands are materially benefitted. Zinser established that, “it [is] not sufficient for an engineer to state that all lands within a watershed would benefit from the construction of a ditch.” Instead, “[t]here must be evidence of a greater benefit than the natural drainage of water.” Specifically, there must be “an improvement to the quality of the soil of the landowners based on better drainage.” Since there was no finding in the B&M report of better drainage due to the improvement, the report did not meet the requirements of §468.119(1) and the lands could not be annexed.