Pool Preserve, Union
The small Pool Preserve is located on two sides of the Georges River. I think the eastern side, off Sennebec Road, might be a bit nicer for a short walk. And there’s interesting old dam equipment rusting by the river here. On this side, you can walk up and down a little road (.2 miles) to reach the two ends of the preserve. If you walk to the southern end, there’s a fire pit, and a nice area where the river slows into a calm pool. On the northern end, you’ll find the dam gear. There’s also a very short walking path next to the preserve sign that goes to a little river perch.
If you walk on the other side off Route 131, it appears that the trail crosses someone’s private property before continuing a short ways farther down the river.
Directions: The Sennebec Road side of the preserve is down an unmarked dirt lane from Sennebec Road, about a mile from Route 17. You can park off to the side, around the drive into the quarry (but don’t block the access to the quarry!). The other part of the preserve on the opposite side of the river is marked with a trail sign, and is also roughly a mile from Route 17.