You post pictures by posting them somewhere else (photobucket and others) then linking to them here.

I'm sorry about your drought problems. I'm not sure you can live with bermuda invading an otherwise fescue lawn. You could try the following.

1. seed heavily now with a mix of fescues and bluegrasses.
2. mow at your mowers highest setting
3. at the first sign of drought, stop mowing and let the grass get tall (10 inches is not too tall)
4. water once a week for at least an hour. If your grass wilts before the next watering, water longer than an hour. I water mine from 1-3 hours per week, all at once.

By letting your grass get tall, it should shade out the bermuda. By letting it get run-away tall during a drought, you can completely shade the soil underneath as if it was mulched.

Another plant that will choke out bermuda is Dutch white clover. When you seed that for 100% coverage, it really looks plush. It doesn't need mowing, water, or fertilizer. It does attract bees, however. Clover coexists pretty well with the fescues and blues as well as other cooler climate grasses.