There is a gravel parking spot just inside of the County Parkland Boundary. Park there and slide on in if you're up for it. But first scout the entire run for strainers. You may need to put-in lower down depending on the tree situation.
During Isais, I parked my car in the middle of the run and walked up to where I had decided to put-in. When I got to my chosen put in I found that in those few minutes, a very large tree had fallen right where I was planning on putting on. I put-in just downstream of the tree.