Originally Posted by jonseim
It can be run pretty low, I've got buddies that do it at 650 or so I believe in October. Fishing on it is another story. You can stick your hand under water and it disappears about 2" down. I've never heard of anyone fishing it, and when I asked, I was told I might catch some silt fish. We bring all our own water as it's pretty silty! This is from Bluff to Mexican Hat.
This is the lower San Juan and is in Utah....not Colorado. The OP, I do believe, is referring to the San Juan upstream of Navajo Reservoir...
Generally 600 at Pagosa is enough to kayak the East Fork San Juan, which is more than enough to float a raft on the main stem. Unfortunately access above Pagosa is kinda poor. I would look for a minimum of 400-500 to float fish the upper, and Mesa Canyon (the stretch below Pagosa) or even the stretch from Trujillo to Navajo would probably be better fishing.