I made two more Brule River Crossings on June 12th, 2014.
3rd stop = Brule River at Hwy 73
This was a quick stop to check under the bridge (46.032529, -88.797263).
Exuviae found included 6 Ophiogomphus sp. and 3 Cordulegaster (likey maculata).
4th stop = Brule River at Hwy189
Another quick stop to check under the bridge (45.987746, -88.652184).
Here I found 6 Ophiogomphus sp.