Hmmm, I have not heard of this. Glad they are on the lookout though. I drive through Cona almost every Morning and have seen nothing odd happening. They musta been netting the creek...which to be honest...I did not know was illegal. Is it because its in a park?
U can see the riv by power plant as clear as day as u drive across bridge so coulda been anyone who "reported" you. I'm glad they questioned you, and I'm glad they left u alone afterwards. Just doing their job.
That outflow used to be a blast when I was younger. Jump from the top into the warm stinky water below....so fun. But....don't try it nowadays, the landing spot has tons of broken bottles in there. We learned this the hard way.
Cheers