I used to strap mine to the bike frame, but I have a bike specifically built to facilitate touring with a camera. This is a cheap Manfrotto tripod rather than my expensive one, used while making sure that the idea worked. The camera goes in the black canvas sack above the tripod, BTW.
One thing no-one else has mentioned is mounting the tripod vertically next to one leg of your front fork. You'll probably find you put it there instead of a front pannier, but with a bit of thought to the mount you'll have it readily accessible and reasonably well protected. I would be tempted to use a PVC pipe section with an end cap as the bottom end, perhaps only ~100mm deep, then a hoop at the top just under the point where the tripod legs pivot. I'd also make a cover for the head of the tripod to keep the rain and dust off it.
What I normally do these days is carry a mini tripod instead. I have tried a whole pile of different ones but eventually gave up and made one. It takes a standard, full size ball head and is almost flat - you could do the same just with a sheet of plywood and a bolt through that for the head, then three bolts down through the plywood as "legs". Mine has horizontal legs, two of which pivot so the whole thing folds into an L shape with the head poking out of the ~150mm long legs. I use ocky straps to tie that to poles or whatever when I want the camera high up, but mostly I just place it on a flat surface. It's made of a length of aluminium "square tube" about 15mm on a side and ~1.5mm wall thickness, and the centre is two bits of ~3mm plate cut to roughly T shapes. It doesn't weigh much.
Top view of my "tripod" - blue hole is where the bolt for the head goes, black holes are the pivot bolts/bolts that hold it together. The grey bars are the three legs in their folded position. I used strips of milk bottle plastic between legs and T piece as washers (6 pieces required, including the non-moving leg). The non-moving leg went all the way under the head bolt so I could tighten that without bending the T plates (I used a button head cap screw for that since the head was underneath, and 6mm socket heads for the rest. It's a few years old now and still works with very little slop, and it held my 1D Canon with 70-200/2.8 zoom quite comfortably.