If the water is down then there are trails leaving South from the main parking area. I just jumped a small drain ditch and found the trail running parralel to the road leading to parking.
The trailhead can be reached by turning east onto Dunham Rd., immediately south of 1171. There is plenty of parking at the trail head, which is at the end of the road. It will be a great hike to take with your son!
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