Create permid:id3dhp and reachcode:mainstem lookup tables and full network table.
Three new tables should be added to the data 3dhp network release.
The first is a lookup table that maps id3dhp:permid This will be useful for people who want to wholesale relate the final NHD to 3DHP -- primarily internal USGS users and for posterity.
The second is reachcode:mainstem. This will be useful for people who want to convert their events to mainstem.
The third is a complete flow network encoded using id3dhp identifiers. This will be useful for people who want to do network navigation on the current 3DHP service.