Original hydrographic data were compiled to meet National Map Accuracy standards. These standards have been maintained in the process of creating the NHD.
For general inquiries, call 1-888-ASK-USGS (1-888-275-8747) or use this website to send us a message or to initiate a live Web chat with a Science Information Specialist.
There are USGS offices in each state. The USGS Headquarters office is located in Reston, Virginia.    
The USGS provides data on many different science topics. Most of it can be downloaded for free from our website. Our Science Data Catalog is a good starting point.
Many volunteer opportunities with United States federal agencies are listed on the Volunteer.gov website.
Volunteers assist on some projects. In all cases, the volunteers are carefully trained. Then they are supervised by a federal employee while they work. In addition, to ensure quality-control, their data are checked by USGS supervisors.
Very few USGS offices are set up to accommodate visitors. Before stopping by a USGS office, you should check their website or call ahead to make sure that visitors are welcome.
The USGS does not have a formal program for providing field trips or classes. USGS employees will sometimes lead field trips or teach classes that are coordinated through an outside organization, but these are not advertised by the USGS.