ive fished it at 600, and i caught fish. obviously you cant wade much at the flow, but the fish get sucked up to the banks. so just use your best judgment and be careful.
watch the TEMPS. with that rain, the gauge is reading 67.4 right now. and it has been hitting 68 degrees for basically the last few days, dropping to just below 67 over night. i didnt fish it saturday or sunday due to the temps being close to the threshold. id recommend you not trout fish that stream for the foreseeable future (until temp drops below 67 consistently)