Looking To Pick Your Skilled Brains

Advice on best how to make a piezometer out of readily available hardware store parts without use of any power tools and access to only a very few hand tools. Basically a piezometer is a clear, straight plastic tube that you attach to the outside of (in my case) a plastic 250 Liter rain barrel (about 1.5 feet diameter, 4 feet high) from top to bottom. The top is exposed to the open air, while the bottom feeds into the bottom of the barrel (by going through the side very close to the bottom). It needs to have a diameter of about 1/2 inch, be very solid, straight and secure, and a 'water level mark' must be etchable in it somehow to indicate the normal level of water inside the barrel when the barrel is full (full means a few inches before the absolute rim of the barrel). The barrel is filled with gravel at the bottom, sand on top, and enough room for a 12" waterhead above the sand. I'm using it as a slow sand filter (SSF). The idea is that the pressure of water at the bottom of the barrel fills the tube up to the watermark against the action of the atmospheric pressure forcing the level in the tube down below the watermark. When the level of the water in the tube is about 15 inches below the water mark, it means the water pressure at the bottom of the barrel has decreased to the point where the sand in it needs to be cleaned (no water getting through). Any ideas will be greatly rewarded in the afterlife. Thanks!

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photozz10 years ago
To keep it cheap, I would guess about 5 feet of clear PVC tube, like so:
http://www.sidewindercomputers.com/dupvctu3id1o.html

then, a 2x4 and some pipe strap. Cut the 2x4 into an L shape and attach it to the barrel, or make a base out of 2x4 adn attach it there. Run the clear tube up the side of the 2x4 with the pipe strap, keeping it tight. Run one end into the bottom of the barrel, sealing it somehow with silicone or whatnot. The 2x4 will give you the room so you can make all the marks you need. I would bend the very top of the tube over so air can escape, but rain won't get in.

Whole thing should cost about 7$.
SozzledBoot (author)  photozz10 years ago
That was fast. Thanks. I really appreciate the effort.