I’ve now had a full season with my mega-sized rain barrel. It’s great. Here’s how it works and what I learned along the way.
The “barrel”: I also have a proper 55 gallon barrel collecting rain from my garage, but the barrel that’s the focus of this post isn’t actually a barrel – it’s a caged IBC tote (“Intermediate bulk container“) that holds a whopping 1,040 liters of rainwater!
I bought it from a local government unit, the Washtenaw County Conservation District (store link). It didn’t fit in my minivan so I carried it home on my cargo bike – that’s a whole ‘nother story that I wrote up as The biggest thing I’ll ever tote on a bike.
I won’t lie, these IBC totes sure are ugly! And mine is visible from the street. Here’s how it looked at first:
I had planned to build a wood screen in front of it and paint a mural or something, but it was simpler to buy online a black cover that zips right on. Also, apparently these totes will grow algae inside if you don’t cover them or paint them black to block out the sunlight, so this was a 2-for-1 solution.
The cover I bought is allegedly rated for the outdoors but I expect I’ll be replacing it in a few years. Lastly, I planted a red osier dogwood shrub in front of the stand. It is lovely and should provide some cover for my de facto water tower.
The stand: a rain barrel is typically elevated to provide (some) water pressure. My stand is homemade out of scrap lumber. When the barrel is full it holds about 1000L of water which weighs 1000 kilograms = 2,200 pounds! The stand had to be beefy.
I hired a carpenter and helped him build, which worked out nicely. We improvised the design together based on lumber we each had; it went faster with two people; and I learned some things. We made the legs different lengths to account for installing on a site with sloping ground.
How to connect to the gutter: I have a strong opinion about this! You can hook a rain barrel up two ways:
1) Keep the existing gutter in place, tapping it with a diverter. When full, the rain barrel backs up into the gutter.
2) Direct the gutter’s entire flow directly into the top of the rain barrel, eliminating the existing gutter past that point. Add an overflow outlet near the top of the barrel.
I considered this for a long time. My existing 55 gallon barrel uses approach #2:
But I decided that #1 is better because:
- Winterizing the barrel is easier: you unhook the diverter and that’s that. For my 55 gallon barrel that uses method #1, I don’t want it to freeze and burst so I flip it over. Then snow melt and rain just runs right onto the site of the barrel and makes a mess. This also applies if you need to abandon or take your barrel offline for some other reason.
- Simplicity: instead of there being two holes in your barrel (one in, one out) there’s just the one. And you don’t need to run a new overflow drain somewhere because you have your existing gutter.
- Aesthetics: I find having a complete gutter run looks nicer.
The hookup: I bought the diverter parts from RainBrothers. Installation was a cinch. At the start and end of the season, I swap the flexi-fit diverter and the winter cover. Their diverter only diverts some fraction of the rain to the barrel, which I like since the other half goes to my rain garden. Both fill gradually.
I sewed the cover back up around the flexible hose:
Anyone local is welcome to borrow my hole saws.
How it performs as a watering device: some people advertise rain barrels as money savers, if they let you replace using water you paid for on your vegetable garden. I grow a garden but I don’t think I save more than a few bucks this way – water is so cheap in Michigan. Say I replace 1,500 gallons of city water in a growing season with rain water – that’s only about 2 CCF or about $8 for me.
A rain barrel is a different watering experience than a garden hose. What you should know about watering with a rain barrel:
- Water pressure depends entirely on the vertical distance between the water and the end of your hose
- You can calculate the expected pressure for the stand you’re designing
- It is much slower than a normal hose no matter how high you raise it
My barrel is pretty elevated by reasonable standards and it’s not exactly blasting. I can water my raised bed 25 feet away but I don’t use a nozzle, I just put the hose down on the ground for a few minutes.
I think it takes over an hour to empty my barrel when full, let’s call it 3 gallons of flow per minute when it’s full and less as the barrel empties. And this is much faster than my 55 gallon barrel.
Many people use soaker hoses with rain barrels because they are designed for low flow rates over long intervals. Maybe I ought to.
How it performs as stormwater infrastructure: this is where it shines!
I enjoy tracking the weather and using the barrel to even out rainfall. During a storm, I’m holding back water that would otherwise be causing the Huron River to surge and threatening damp basements. Then I gradually release the water during a dry spell. My mega-barrel can keep my vegetables and native plantings watered for several weeks during a drought.
It’s good for the ecosystem, offsetting some of the impervious surface of the house and driveway, and it helps me connect to the rhythms of the water cycle. Each rain barrel doesn’t make much difference on its own, even my big one – but when many people get them it adds up.
There’s a small financial upside here too as the City of Ann Arbor pays you to have a rain barrel (in the form of a stormwater tax credit). I get $15/year for my rain barrel and $32/year for my rain garden. I’ll never make back what I spent installing them but it’s nice.
There you have it. Rain barrels: they’re good for the earth but most of all they’re fun!