A feature is a representation of a real world object, such as a lake, stream, dam or rapid. There are three hydrographic feature classes: points, lines and polys. All may impede or be hazardous to waterflow and/or navigation on a watercourse or waterbody. This data shows natural and manmade line features. Examples include: * break walls * dams * waterfalls * lock-gates * rapids * rocks * Sea Lamprey barriers * shipwrecks This product requires the use of geographic information system (GIS) software. Technical Bulletin: Data migrated to new Ontario Hydro Network (OHN) - Hydrographic Feature Data Classes (PDF)