The North Dakota state coverage was created by the North Dakota State Water Commission and is a subset of the NDHUB county coverage (see the county layer metadata for the data history). This coverage has been primarily derived by head's-up digitizing the boundaries from 7.5' USGS DRGs. The resultant coverage should be much better than a 1:100,000 scale coverage, but may not meet 1:24,000 scale accuracy standards.