I have visited the Whiskeytown Glory Hole but I didn't realize we had one closer to home.
Which reminds me that I have yet to drop a video camera down the chute and into my building's trash compactor.
I can think of no better application of ten million rubber ducks.
The guide vanes on the Whiskeytown one - are they straight or helical? Can't quite tell for sure from the google but I think straight.
Helical would look cooler, but maybe they modeled it and found it would decrease flow or open up a portal or something.
If you want to make a day of glory-hole viewing, it's just about an hour 15 out of SF on a low-traffic day. That viewing location is easy to find, when the road is open. That said, it's just a big drain after a few minutes of viewing (we went up the last time it was up over in ~2010 or so).
At least there's a decent bar also a brewery/winery in or near Winters now to stop at on your way up or back.
The last time it flowed was June, 2006.
I'm not even trypophobic but this video makes me incredibly anxious until the part where I can just imagine it's an iTunes visualizer.
it's like looking into the eye of goatse
but, you know. less romantic.