Description: Horizontal Control Network (Monuments) The horizontal control network is comprised mostly of section and 1/4 section corner markers throughout the county. These locations were first determined as a result of the nation wide PLSS (Public Land Survey System) Program, which was a cornerstone to the Federal Land Grant Program in the mid 1800s. The PLSS was intended to simplify the defining and documenting of land ownership in the handover of federal lands to private ownership. At the time, the corners were marked with a variety of things, including stones, spikes, iron posts or nails in pavement. From 1979 to 1984, DuPage County initiated a county-wide re-monumentation program with specific objectives. Questionable corner markers were replaced with more durable and permanent monuments, mostly Harrison Ferro-Magnetic Survey Monuments that still exist today. And most importantly, for the first time the DuPage County PLSS was spatially referenced to the NGS (National Geodetic Survey) control network. Prior to this, there had been no coordinates assigned to the section corners. The level of precision is less than 1 ft varience for every 20,000 ft traveled, or second order class II.
Copyright Text: DuPage County Information Technology Department GIS Divisioni - 630-407-5000