Surface Drainage-Main or Lateral on Agricultural Land in the Conterminous United States, 1992: National Resource Inventory Conservation Practice 608

This data set represents the estimated percentage of the 1-km grid cell that is covered by or subject to the
agricultural conservation practice (CP608), Surface Drainage, Main or Laterals (SDML) on agricultural land
by county. Surface Drainage, Main or Laterals are described as "an open drainage ditch constructed to a
designed size and grade. [As] part of a water management system to collect and convey excess surface
or subsurface water.