How We Harvest Rainwater. And Why.

Before we share our favorite way to connect an above-ground rain tank to your home’s gutter and downspout system, perhaps a word or two about the reason we even install above-ground rain harvesting tanks would be timely and useful.

In some parts of the world - and at certain times in history - ( from ancient to today ) -  rain water was harvested and used for drinking, bathing, washing, and agriculture. It might not even be a stretch to say that life in many hot dry areas wouldn’t feasible without large rainwater storage cisterns, and all manner of clever ways to channel rainwater into these rainwater storage tanks.

 

Human necessity is certainly a good reason to harvest rainwater, if that’s indeed the reason.

But here in the Charlotte area - where a well-run municipal water supply feeds potable drinking water into sinks, showers, bathtubs, toilets, spigots, and landscape irrigation systems - rarely with interruption or restriction - why even take the trouble and expense to harvest rainwater here?

 

The primary  - really the only reason - that we install above-ground rain tanks is because the benefit of rainwater for organic garden plants is substantially greater than the same amount of treated water from the  city water supply - even if the treated water has been though the most advanced, military grade filters in our entire solar system. 

If you doubt our view on this, simply observe the plants in your own yard for the next month or so. Grass, shrubs, edible plans, trees, even weeds. Just observe whatever it is that you have out there.

If you don’t have any outdoor plants, find a park or another nearby locale and take note of the plants there.

 

You’ll soon find that during summer dry spells - periods of a week or even several weeks without rain - these plants tend to look just okay with supplemental watering from the city’s municipal water supply. That’s supplemental watering either by hand with a garden hose, or though an automated irrigation system.

 

With heavy assistance from supplemental water, lawns can stay mostly green, shrubs look decent, organic gardens keep chugging along, like the little engine that could. 

And the weeds...well, they seem not to really care much about water, actually, so let’s just focus on the other plants for this informal experiment, okay?

 

Now, pay attention to these plants ( the very same plants you’ve chosen, so that we can prove or disprove our hypothesis accurately ) after a heavy summer downpour. One of those big summer thunderstorms that sweep into the Charlotte area, with dark clouds, swaying trees, and heavy rainfall that has windshield wiper blades set on HI and drivers inching along, hazard lights flashing. Puddles everywhere when its’ all over. You can picture it, now, yeah?

Just a few minutes into this heavy downpour, these very same plants that looked just kinda ‘ehhh’, instantly spring to life. Stems, trunks, and branches stand up straighter. Leaves turn a darker, healthier green, and reach for the sky again. Tan spots in the yard turn green. The droopy-looking plants in your organic garden, that were really just kept on life-support by all that hand watering and irrigation, seem to jump for joy when all that rain soaks in.

 

We’ve found that rainwater - whether it’s delivered from the sky or from a rainwater harvesting tank - is much more beneficial to plants than treated water - even treated water that’s been filtered. 

That’s the reason we install rain tanks here in the Charlotte area ;  rainwater is just better for your plants.

Now, that’s just the reason we install above-ground rain tanks.

There are some potential financial benefits for builders ad homeowners to offset non-porous surfaces by collecting some of the watershed from large concrete driveways, homes with a large roof area, backyard tennis court, etc. 

But before you get excited about all the money you’ll save, consider that the amount of rainwater flowing from the roof of even a modest-sized home can be hundreds or even thousands of gallons, in even a modest-sized rain event.

 

It’s, perhaps, unrealistic to think you might collect every drop of rainwater from your new 10,000 square foot home or full-sized backyard basketball court.

So, the reason to go to the trouble to harvest rainwater - at least here at Microfarm - is to give your plants the water they love best, during those long, hot, dry stretches in the summer months.

And since some hundreds of gallons of rain water is usually enough to accomplish this, our niche is installing above-ground rain harvesting tanks in the 150 to 1000 gallon capacity range.

 

Now, we have installed plenty of 80 gallon rain barrels, but we’e found that two or more of these rain barrels are often needed to make it through a long summer dry spell here in the Charlotte area. Fortunately, rain barrels and larger rain tanks can be easily connected to each other to increase the rainwater harvesting potential from a single downspout connection.

And, finally to the real purpose of this article ( Hopefully your’e still with us! ).

How exactly should you connect your above-ground rain tank to an existing gutter downspout? What’s the best way to go about this important step in the rainwater harvesting process?

Well, remember what we mentioned earlier in this article about how much rain water even a modest sized roof can shed during a storm?

It can be hundreds or even thousands of gallons, and you can click here to calculate exactly how much water your home, shed, chicken coop, garage, greenhouse, etc. can collect.

After completing your calculation, you find that 1000 gallons of rainwater will flow down just one downspout in a single thunderstorm, and there’s only enough space for a smaller-sized tank - say a 250 gallon above-ground rain tank - then you must ask yourself ; where will the other 750 gallons of rain water go when my 250 gallon rain harvesting tank fills up?

The answer to this question matters. A lot, actually.

Too often, rain harvesters out there get excited and remove an entire section of downspout, install a flexible elbow, and divert ALL of the rainwater from the downspout into the rain barrel or tank.

Maybe at first blush this seems like the obvious even the most logical way to go about it.

After all - we’ve come this far, why not harvest every last drop?

But we advise against this. 

Strongly.

 

Because, collecting rainwater typically requires that an above-ground rainwater harvesting tank or rain barrel be within a few feet of a gutter downspout, that means that the rain tank will be within a few feet of the structure that the downspout is mounted on. 

If ALL 1000 gallons of rainwater from that single thunderstorm are channeled into your 250 gallon above-ground rain tank, then the tank will soon overflow, with the remaining 750 gallons puddling up on the ground around the tank. Probably beside your home, garage, or greenhouse’s foundation.

The ‘drinking from a firehose’ metaphor seems fitting here - if that helps you visualize it better.

And to avoid this undesirable scenario, we use a simple, inexpensive, but very, very clever rainwater diverter kit that allows rainwater to bypass the rain tank, once the tank has filled up during a rainstorm.

 

Once your 80 gallon rain barrel, or 750 gallon above-ground rain tank fills up, rainwater bypasses the flexible diverter cup, and continues through your downspout, off to it’s original destination - one that’s hopefully away from your home, greenhouse, garage, or other structure’s foundation.

The EarthMinded Universal Rain Barrel Diverter System accomplishes this important objective surprisingly well. 

it’s our favorite.

The kit is easy to install, budget friendly, and requires drilling just one small hole in your gutter downspout. The result is a professional and tidy-looking connection, and a rainwater harvesting system that won’t overflow the  rain tank in a heavy downpour.

Want to harvest rainwater in an-above ground rain tank to have it on hand for your garden plants during the hot summer months, here in Charlotte?

Drop us a line!

Interested in harvesting rainwater to go ‘off grid’?

Want to install a massive, below-ground cistern on your property, complete with electric pumps to push all those thousands of gallons of rainwater through an irrigation system?

Sorry, that’s not our ‘jam’.

BUT... if you’re looking for more than just supplemental water for your organic garden, we’re delighted to suggest that you to check out out the many rainwater harvesting tanks, cisterns, diverters, filters, pumps, and other rainwater harvesting products at Spartanburg, SC-based North American Rain Systems. 

They can almost surely help.

Tell ‘em Microfarm Organic Gardens sent ya!