Monster Lake does not flow into the Mazon River, it flows into a drainage creek. Take a look at the arial photo of the place on the microsoft terraserver and you'll see that the Mazonia South Unit is not near the Mazon. There are two places in the North Unit that I know of that do connect to the Mazon and are only passable at very high water. However, you can rough it through the bramble by the shore to get back to the Mazon.