Boardman Township, Clayton County, Iowa  Boardman Township is a township in Clayton County, Iowa, USA. As of the 2000 census, its population was 1,832. Boardman Township is named for Elisha Boardman, who settled there in 1836. Boardman Township covers an area of and contains one incorporated settlement, Elkader (the county seat). According to the USGS, it contains three cemeteries: Eastside, Erhardt and Saint Josephs. The streams of Dry Mill Creek and Roberts Creek run through this township. Boardman Township contains Elkader Municipal Airport.