FAQ
Frequently asked questions about understanding and interpreting USGS water data
- About the USGS Water Data for the Nation site
- About groundwater
- About output formats
- About sites
- About site selection criteria
- About surface water
- About tab-delimited output
- About water quality
- About WaterAlert
- Additional background
- Automated retrievals
- Useful tips if you need to get data automatically from this site
- Miscellaneous questions
- Dynamic graphing questions