Where are USGS instantaneous stream water quality sites located?
I looked at all active CONUS NWIS sites in 2024 that were recording common water quality measures (discharge, dissolved oxygen, specific conductance, turbidity, water temperature) to see what the surrounding land cover was. 46% of sites were situated in areas where natural land cover was the dominant (>=60 %) class. By contrast, only 9% of sites were located where agriculture was the dominant class.
If you are interested in a deep dive into global bias of stream gauge locations, check out Krabbenhoft et al. (2022) for an excellent analysis.
