Next, I dug a trench around the perimeter of the patio and filled it with lots of
rebar and concrete. On this footing of concrete, I built a wall of limestone 3 feet high. In this wall I put some limestone fossils which I found around our property. All of the limestone was free for the asking from the garbage piles leftover from houses being build! I also got permission to get scrap rock that I used to fill-in the patio. In addition to the scrap rock, I plumbed up four 55 gallon barrels to gather rain water from the patio. You can see them buried here. I put layers of decking material over the barrels to make sure that any weight would be distributed over the barrels.
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Each barrel has 1) an inlet for water, 2) an
up-riser pipe to let out air, and 3) an outlet pipe that siphons water from the bottom of the barrel.