[Greenbuilding] Rainbarrels

[Tim Martens]

Hi David,  

I had a nursery once that relied on water from a well more than 600 feet away. So, without doing any math (not an option for me), I just started with one barrel and figured it out, trial and error.

There was practically no pressure from the garden hose from the house. The advantage of this is that the water is air temperature when your ready to water which reduces the stress on the plants. Also, if you  want to fertilize the plants you can brew an organic tea in the barrel with fish emultion or nettle (the latter was used by a local organic farmer- he said it was an excellent fertilizer) high in potassium? I think.

This is what I learned.

1.The resulting pressure varies with height, not volume.  I had 4 barrels in a cluster with a fifth perched on top. The best pressure came from the top barrel ; the bottom 4 were connected together with a 4 way fitting and all worked together as a unit but still had less pressure that diminished as they emptied.

2. I got better pressure at the sprinklers if the hose from the barrels was inch and a half vs. three quarter. (I'm sure you guys who know why this is are chuckling by now). 

3. This I found interesting (again, I can hear the snickering beginning). If I filled up the top barrel with the value open at the barrel, the water would run 13 feet down ( the tower was 13 feet high) to the other valve and back up to the 4 barrels just beneath the top one.

4. I was able to operate 20 shrub head sprinklers with this pressure covering an area of approximately  480 square feet.

Tim Martens