Introduction: Rainwater Cistern
To make this, you will need:
- Aa 55 gallon plastic drum with the screw caps intact
- The following pieces of 2x6 pressure treated (PT) lumber:
- (4) 28.5"
- (7) 24"
- (4) 23"
- (4) 18"
- (2) 13"
Step 1: Get a Leg Up
Start by glueing and screwing 2 lengths of 2x6 together, keeping the bottom end flush. They are 28.5" and 23" long, respectively.
Step 2: Two Legs Are Better Than One
Repeat step 1 to make a built-up second leg.
Step 3: A Time to Join
Next, cut an 18" piece of 2x6 and glue & screw it between 2 of the legs.
Step 4: Have a Pair
Now repeat steps 1-3 so you have an identical U-shaped assembly.
Step 5: Come Together
Now, cut a 24" piece of 2x6, and slap some adhesive on the 'notches' at the top ends of the 2 leg assemblies. Place the 24" 2x6 and screw it in.
Step 6: Deja Vu
Repeat step 5 for the other side.
Step 7: Sister Marry Me Please
The next thing is to sister up the 4 leg stretchers to beef them up a bit. For this, you will need two 18" and two 13" pieces of 2x6. Glue and screw them in place.
Step 8: Top It Off
The last part of the stand construction is to make the top. Just use whatever 2x material you have, cut them to 24" length and space them evenly. You could make an overhang if you wish, but I preferred the cleaner look of making it flush. Remember to put a space between boards to give rainwater a place to drain.
Step 9: Down the Drain
The next step is to prepare the stand for the barrel's drain. This requires drilling a hole in the top, and another in the side. There will be a 3/4" PVC pipe that exits the barrel, and turns 90 degrees to protrude out of the stand's side. I chose a 1-1/2" drill bit for the hole on the top (to allow a little bit of wiggle room), and a smaller one for the hole in the front.
With the 2 holes drilled, next you must attach the PVC to the drum's screw on cap. However, to keep sediment from entering the drain, I added a riser to the inside of the cap. The riser is nothing more than a 2" PVC coupling. I mixed up some epoxy, poured it in the recess and stuck the coupling on. For my drum, the cap is outfitted with a threaded hole that fit a 3/4" threaded male coupling perfectly.
Now it is time to assemble the 3/4" PVC components that make up the rest of the drain. Note that some of them need to be assembled once the barrel is in it's final resting place. See the 'exploded view' for a complete visual of which pieces go where. Basically, the vertical parts can be assemled/attached, then you place the barrel on the stand, then you assemble/attach the horizontal parts.
Step 10: A Solid Foundation
With the drain pipe installed on the barrel, now you must pick a spot for the barrel and prepare the foundation. For me, it was directly under the gutter's downspout. The foundation itself is nothing more than 4 chunks of pressure treated 4x6 wood, placed on level ground. Cinder blocks would work too - the main idea is to spread out the weight of the full barrel.
Step 11: Connect to Gutter
Next the rainwater needs to be diverted into the barrel. Your application may differ, but the basic premise is to pipe the water into a hole cut in the top of the barrel. For me, a 3" to 2" PVC reducer fit perfectly onto the gutter's flange (attached with sheet metal screws). I came out of the reducer with a 2" PVC elbow, then another, then a 6" length of 2" PVC, directly into the barrel.
Step 12: Overflow Mechanism
When the barrel is full, you will want additional rainwater to take it's normal course through the downspout. To achieve this, I used the male and female 2" PVC adapters, a 2" PVC elbow, and a short piece of 2" PVC. Cut a round hole in the side of the barrel at the elevation you want to be the high water mark. Make the hole sized so the male adapter will fit snug. Pass the male adapter through, and screw on the female adapter. Now you have a PVC fitting on which to glue the elbow (on the outside), then a short piece of 2" PVC which sticks into the downspout.