The annual summary of water records activities in Colorado is presented for fiscal year 1986. The report includes an introduction of these activities and names of the management personnel to whom information requests may be addressed; a summary of the U.S. Geological Survey mission and of the Water Resources Division mission; and a discussion of the water conditions in Colorado in fiscal year 1986, including data collection on surface water and groundwater. All current Colorado hydrologic investigations are listed--their problems, objectives, approaches, progress, and plans for fiscal year 1986. A list of current cooperators for fiscal year 1986 and a list of reports published or released during fiscal year 1984, 1985, and 1986 also are given. (USGS)