Rain Water Collections System

Last year watering my little garden from water I collected in buckets from the roof was very labor intensive and soon the 40 gallons ran out during the dry summer and I had to use city water from the barn. This year I wanted to collect a lot more rain water so I designed up this system with 3- 55 gallon barrels. I originally wanted food grade barrels with removable lids but the guy who had them jacked the price way up so I looked for an alternative. I found  local guy with blue barrels and white barrels- both food grade but the difference is that the threaded plugs in the white barrels are English threads and the blue ones are metric. I found out that the threads are the same as the 2"  11 1/2 TPI pipe threads, only they are straight- no taper. I put PVC pipe fittings in them and cranked them real tight. I mounted the barrels  upside down! I put in  6 aluminum uprights  so I could tie the barrels to them in case of high winds when they are empty. Moving any of them could damage the manifold below.

The three barrels are mounted on a frame made from  treated lumber. The posts have tenons turned on both ends and fit in the upper and lower frames and have a screw through each tenon. The barrels are connected underneath with a PVC manifold so they all fill up equally.
I put an overflow pipe on the left side and it worked like a charm last night in the big thunder storm. It was the first rain since I installed them and they are all filled to the overflow level.

I have two gate valves under the manifold to drain the barrels in the winter and a diverter valve on the downspout so the water will not go into them for the winter months. There is also a plug that replaces the screen in the top of the left barrel.

I have a few process shots of the build:

The base is a frame mounted on packed sand

I made a 12" base for my router so I could finish out the dados for the cross 2x6's

The finished upper frame with and clearance cut out for the pipes out of the bottom of the barrels

The holes for the tenons were bored into the base on the drill press and then transferred to the underside of the top frame to insure alignment.

Each leg was turned with two 1 1/2 " long tenons while holding the center dimension on each one to 25".The checking fixture for tenon diameter is laying in the chips.

Who dat????

Assemble was done in the barn. I was amazed that the old round table held all that weight.

I needed to install an overflow fitting which was a 1 1/2" pipe thread. I found a steel  fitting with the same thread and made a "tap" out of it and threaded the side of the barrels and screwed in the fitting for the overflow