This data represents LiDAR-derived breaklines for Rock County, Wisconsin in 2020. Hydro breaklines maintain the definition of water-related features in an elevation model. They are used to capture linear discontinuities in the surface, lake shorelines, single-line drains for small rivers, and double-line drains for large rivers.
Detailed metadata for this data can be accessed here: https://bin.ssec.wisc.edu/pub/wisconsinview/lidar/Rock/Rock_2020_3DEP_Delivery/metadata/