As of July 2009, the Colorado Division of Water Resources (DWR) entered into an MOU with the USGS to officially steward the National Hydrography Dataset (NHD).  Using the recommendations and findings from a pilot study conducted in the previous year, DWR has begun a tiered base approach to maintenance of the NHD.  Tier 1 consists of low level edits involving geometry and attribute issues.  Tier 2 edits are comprised of adding value added data, such as, DWR data, uncollected features and other data from the Department of Natural Resources.  Tier 3 edits involve photo revision of features or an overhaul of the data itself.  Currently, Colorado is focusing on the first 2 tiers of edits while keeping an eye on the possibility of tier 3 edits in the future.

To get involved in NHD stewardship or to sign up for bi-annual steering committee meetings, contact Chris Brown at DWR: Chris.k.brown@state.co.us.

For more information on the National Hydrography Dataset (the surface water component of the National Map) go to: http://nhd.usgs.gov/.