My goal was to create a modular barrel system that was first and foremost, CHEAP. I was inspired by a couple of other great rainwater reclamation systems here and felt I could put a different spin on the process.
This project came in at 220 gallons of water storage for less than 30 bucks a barrel. Everything was purchased via 'the bay' or 'home despot' except the barrels which I found on 'cragg's last'.
at the end I'll review some changes I'd make if I had it to do over again- but they're working great here in the wet N. Texas.
Step 1: Ingredients:
My list of materials:
4 55 gallon blue barrels (for the love of god make sure they're food grade, otherwise prepare to water your lovely garden with acetone, gasoline, or any of a dozen other lovely chemicals).
4 2 inch through-hull connectors- I'll discuss these lovely widgets later on.
2 threaded 2in PVC connectors (overflow)
18in of 2in ID (inside diameter) flexible hose (this stuff is big $$!)
2 standard threaded brass hose bibbs (connector thingies for garden hose- mine were 1/2in on the hose side and 3/4in on the 'connect to barrel' side).
2 4in drain hole covers
Dremel plastic/wood cutting bit for smoothing or widening holes in the barrel
Step 2: Prepping the bung hole
I needed an easy way to keep leaves and other 'unmentionables' from getting into my rain barrel through the bung (yes- I'll be using that word liberally as it's the official term for 'barrel hole').
Using my trusty drill I drilled out one of the threaded bung holes to fit my drainage grate. This green widget keeps leaves out and water in. There are a lot of ways to keep leaves out, this just seemed to work and is CHEAP. As of now I do have to manually clean leaves out of the downspout, but none clog up my bung hole!
Step 3: Tying Two Together
After hunting for bits and pieces I came across the perfect fitting- a through-hull. These are used on boats to pass fluid (grey water and cooling for engines I presume) through the hull without sinking the boat.
I drilled a 2 inch hole and put one of these fittings about 6-8 inches from the bottom of each barrel. Since these fittings are typically barbed, it made for a great fit with the plastic tubing. Just make sure the through-hull fitting and the tubing are the same diameter.
The easiest thing I found was to fish the through-hull through the reamed bung hole (yes- I reamed 4 bung holes to complete this project) using a coat hanger. I placed a nice bead of marine grade silicone on the flange and tightened the nut from the outside of the barrel. This cinched down nicely and made a watertight fitting.
I tried this with an 18in length of tubing and found that 1/2 that length is better.
Step 4: Fluid Release Systems
The obvious way to release pent up water is to have a hose and hose bibb at the bottom of the second barrel. REMEMBER KIDS: water flows downhill, therefore, make sure barrel two is DOWNHILL of barrel one. this allows them to both fill and for water to come out of the hose when you want to water something.
These barrels are quite thick. I placed the bibb at the bottom of barrel 2 about 4in off the ground. Low enough to get most of the water out, high enough to keep the hose from kinking. I drilled a 1/2in hole in the side of the barrel and slowly dremeled the hole wider until the brass fitting cut its own threading into the plastic, leaving me with a strong, watertight seal. It's key not to ream this hole too large or you'll have a leaky bibb.
Do the same thing up top for your OVERFLOW. Overflow is important. 1in of rain on a 1000sqft roof will give you about 623 gallons of runoff. since my gutters cover 1/2 of my roof footage (about 1200 sqft) I anticipate these barrels being full at some point. When that happens I want to make sure the excess water heads out to the street to the public drainage system. Drill a 1 3/4 in hole in the top side of the barrel and ream until the PVC fitting will cut a thread in the sidewall to create an overflow.
Step 5: Final Thoughts
If I were to do this again I would countersink the grate on the bung hole or possibly a leaf trap on the down spout. I would also place the connector tube lower down the barrels, as it stands I may just add a hose bibb to barrel one if I find I'm having standing water most of the time.