Overflow rain barrels in action.

We got some heavy rain the other night.  I was anxious to see how well my overflow barrels worked.  I waited for the rain to let up a bit and went out to check.  To my surprise, overflow barrel #2 hardly had anything in it.

Originally I had attached irrigation tubing to the lower overflow of the barrel at the corner of my house and ran it to overflow barrel #2.  I think the 1/2" tubing is a real bottleneck.  It just doesn't have the ability to transfer water very quickly.  So I moved the tubing from the overflow to the hose bib (pictured above).  This worked.  My overflow barrel was full in the morning.

Overflow barrel #3 was full as well.  The float valve worked and stopped the flow of water into the barrel.

Great!  With this setup I can fill both of my overflow barrels.  The downside is that I can't get any water out of the barrel at the corner of my house.  Luckily I already had a solution.  I bought a 5-way hose manifold from Amazon the other day knowing that I'd find a use for it somewhere.

Now I can get water out of this barrel and it's plumbed to my regular rain barrels and my overflow barrels.  I thought everything was great.  Then I looked in the barrel and noticed that it wasn't full.  I checked the barrels under my other downspouts.  They were 8-10" low too.  I thought to myself, "Huh.  That's odd."  Then I realized what I had feared had actually happened.  Overflow barrel #2 is lower than the rest of the barrels.  The water flowed from the higher barrels to the lower one and exited through its overflow until they all reached the same level.

I thought of a few ways to deal with this.  I could put a hose cap on the over flow.  I have doubts about how well this would work.  When water enters the barrel the air needs a way to escape.  The lid on that barrel is solid with just a few 1/16" holes for drainage.  That may be enough, but it may not.

My next thought was to install another float valve and still fill the barrel from the bottom.  When the water is low the valve would be open and would allow the air out.  When the water got high enough the valve would close and no more air would escape.  The problem with this is that I don't have any more float valves and I'm too impatient to wait for another one to arrive.

I ended up doing the third thing I thought of.  I've attached PVC pipe to the overflows on my previous barrels.  They let me direct the water away from the house.  Well, I figured I could just do the same thing.  Only this time I'd point the pipe towards the sky. 

This will allow air to escape the barrel as it fills and it raises how high the water has to be before it'll overflow.  It is possible that it could still penetrate the holes in the lid and overflow that way.  I'm hoping that it doesn't.  I'll just have to wait and see what happens.  The only option I have after that is raising the barrel.  I really don't want to do that.  I want to keep it out of sight.