Pesticides in streams
Keep an eye open in your travels for landscape and lawn care companies filling their spray trucks in streams.
Years ago this used to be a common practice amongst tree sprayers, to flush out and refill their spray tanks in streams. With the current proliferation of lawn care types spraying pesticides this practice may be resurfacing.
While many lawn care pesticides and herbicides are relatively harmless when applied properly to lawns and landscape plants, they can be highly toxic to aquatic life in streams. A small amount back washed from a spray tank into the stream could wipe out a significant portion of the streams aquatic inhabitants.
I don't know how often this is happening, however this spring there have been some reports of it happening in my area.
If you see this sort of thing happening write down the company name and plate # and report it.