Catching the Rain

Last winter, January and February of 2011, the hard workers from Wick Buildings braved cold and snow to build us a shed that could house our equipment on the farm (previously we had been storing equipment in corners of rented sheds all over the township).

Shed under construction.

In planning the shed, we made two major arrangements with future conservation efforts in mind. First, we situated the shed so that its ends face east and west, making for a large roof face toward the south – in case we ever want to put solar panels up there.

Second, we asked our salesman from Wick to design the gutters so that they all ran to the same place at the west end of the building, with the idea that we might someday set up a rainwater catchment system from which we could irrigate our test garden crops (our grain crops are “dry-land” crops, meaning that they grow without irrigation).

The west end of the building featured a big Y all last year, probably prompting our neighbors to ask “whY?” In 2011, all the rain that fell on the shed roof was spouted out the west end and into a little drainage field of rocks that we’d picked up from the fields.

A little history:

When we started working on this farm back in 2010, our irrigation system consisted of a small livestock feed tank on a trailer, covered by a piece of plastic:

A larger-scale, more sophisticated system was soon developed: my dad got an old wagon at a sale, sold the box for scrap, and built a platform that would sit on the running gear. We got a used 750-gallon fertilizer tank for free, cleaned it very thoroughly, and installed it on the platform. Now we had a big water tank on wheels! Every once in a while we trundled it down the road to fill it from the well at my cousins’ house, keeping track of how much we used and paying them yearly.

The tank-on-wheels worked pretty well – we could pull it around to water all our tree plantings in the conservation/restoration areas on the farm (as my dad is doing above), and we set up a drip irrigation system for the garden that we could just plug in to the tank when the ground dried out between rains.

This winter when we went to Cuba, though, we saw several urban farms practicing the same kind of rainwater catchment we had been planning and talking about for years.

Whenever people asked us whether we learned anything from the Cuban farmers that we wanted to use on our farm, we said, “Well, they’re actually doing a number of things that we are planning….” Like this:

Rainwater collection bin, collecting water from the roof of the business next door. We have big plans to implement a rainwater catchment system on our farm, but the collection container hasn’t been installed yet.

I guess we just needed to see it in action to spur us on.

A couple of weeks ago we ordered two 2500-gallon tanks from our local farm supply store. When we went to pick them up, the wind was rolling them around in the yard – despite the fact that they are 8 feet in diameter, 8 feet high, and weight 400 pounds each! We had to keep them in the shed until they could be installed, to keep them from rolling away across the field.

Afraid that the weight of the full tank could cause a puncture on the bed of gravel where they would be placed, we made a little pad out of ag lime (which looks a lot like thick sand) for each tank to sit on.

My cousin Tom helped us maneuver the tanks into place, and we immediately put some bolts through the shed wall and strapped them to the shed with the same heavy-duty straps that truckers use to hold down loads on their flatbed trailers.

Then it was time for the plumbing. We had to make something that was secure enough to withstand the strong prairie winds (we have had 60 mph winds out here), but it also had to be flexible enough to avoid breakage in the wind or as the tanks settled on their sandy resting pads. It had to be able to handle a large volume of water at once. Any piping had to connect to 4″x3″ gutter downspouts, which were already attached to the building.

After many nights lying awake, drawing plans in his head, my dad hit upon a solution:

A superstructure made out of untreated Douglas Fir boards (we don’t want those lumber treatment chemicals washing onto the garden!) holds the redirected downspouts as they come out from the building and separate to fill the tanks. The structure is held to the tanks, and the metal downspouts are held to the redirection pipes, by strong rubber bungee cords to allow them to flex.

Then we put in a second set of downspouts that bypass the tanks, for winter (when we don’t want water to freeze in the tanks and burst) or for times when the tanks are full. The metal downspouts are surprisingly flexible; the plan is to just unfasten the bungee cords and move them to the bypass spouts as needed.

An overflow opening was drilled at the top of the tank – that’s the little black elbow that you see just under the board. We will attach additional downspouts from the overflow spigots in case of a heavy rain, so it doesn’t all just come out the top of the tank and cause erosion. Two-inch piping connects the two tanks at the bottom so that the water will equalize, in case there’s a major wind during a rainstorm and one side of the shed gets significantly more rainfall than the other. Soon, we will install a set of garden hose spigots at the bottom to which we can attach our drip irrigation system.

The structure was finally in place last Friday evening. That night, we got 0.4 inches of rain…which meant more than 600 gallons in each tank.

Ta-da! It worked!

Rainwater, caught!

Two inches of rain should fill both tanks.

What’s the big deal about catching rainwater?

When we use well water, we are slowly depleting aquifers (underground water reserves) and lowering the water table (making that underground water harder to access). As populations increase, more and more people need well water for drinking, and the pressure on aquifers also increases.

Additionally, folks who live in a town or city are using treated water when they water their gardens with city water – while it’s important to kill potentially harmful bacteria in water that we drink, plants don’t like the chlorine and other chemicals that’s used to do it. Besides, it takes a lot of resources to put water through that treatment process.

Using well water means using energy, both to pump the water out of the ground and to deliver it to our watering hoses. For most folks, that means pumping it through a city water system; for us, that means driving it a mile down the road from my cousins’ house. And energy costs money.

Buildings cause a different set of problems. When we build a building, a large area (in the case of our shed, 6,240 square feet) that used to absorb rainwater now just dumps all that rainwater into one place, often causing or contributing to flooding and erosion issues.

When we catch the rain that falls on our shed and then use it to water our garden instead of well water, we are decreasing flooding and erosion, increasing access to drinking water, decreasing our overall energy use, saving money, and growing healthier plants. We think that’s a big deal!

– Molly.