This data represents culvert inventory for Wisconsin in 2021. [This layer was developed in 2019 as part of the statewide conversion of all cross draining culvert pipes maintained by Division of Transportation System Development (DTSD) Regional maintenance staff. This layer does not include larger “C” structures (which are inspected by DTSD, Bureau of Structures and maintained in the Highway Structure Information System (HSIS)). The location of all culverts are collected via latitude and longitude in ArcGIS Field Maps. This culvert layer is updated monthly as annual inspections are completed. The frequency of culvert pipe inspections are to be every 4 years. The initial inventory of all culvert locations should be completed by the end of 2022.]