Local farmers and ranchers began constructing irrigation canals to bring water from the Mancos River to cropland and pasture in various parts of the Mancos Valley in the late 1870s and 1880s, and by the beginning of the 20th century a large network of irrigation ditches and laterals was operating and continues to operate (with improvements) today. In the mid-2000s, a large project, the Mancos Valley Salinity Control Project, was funded by various sources, including the US Bureau of Reclamation, the Natural Resources Conservation Service, and local irrigation and water companies and districts. The project, nearly complete in 2010, includes replacing many open irrigation ditches with piping to conserve water and prevent salt contamination from infiltration and evaporation of irrigation water. Many of the original irrigation ditches have been determined to be eligible for the National Register of Historic Places, together with various archeological sites.