Output file mapping nhdplushr and nhdhr to mainstem ids.
The nhdplushr workflow will assume that the nhdhr workflow has been completed and read in the initial mainstem network from 3dhp / nhdhr.
Everywhere that NHDPlusV2, NHDPlusHR, and NHDHR agree will be promoted to a reference mainstem.
Everywhere that NHDHR and NHDPlusHR agree can be mapped to eachother by mianstem id and have drainage area transferred.