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Cisterns and Tanks and Barrels – Oh My! The Disadvantages of Rainwater Harvesting

As concern grows worldwide about the ever-increasing shortage of water, more people are becoming aware of the need to conserve water. There are many ways to go about doing that. And as with most things, many methods of water conservation come with both positives and negatives.

One water conservation method that has begun to get lots of attention lately is the harvesting of rainwater. Many homeowners are turning to rainwater harvesting as a means of reducing the amount of water they need to purchase for watering landscapes and lawns.


It’s certainly an attractive idea. And indeed, harvesting rainwater can offer some nice benefits. After all, rainwater is free. And usually – though not always – rainwater is a source of clean, pure water.

But rainwater harvesting also comes with some distinct disadvantages:

  • Cost: Rainwater is free. But the cost of setting up a system for the collection and storage of rainwater is anything but free. It can cost up to $2,000 to install a rainwater harvesting system from scratch.
  • Reliability: Rainfall, of course, occurs at random. We can predict when it might happen, but we can’t control when it does happen. And that means that during the worst times of drought, a rainwater harvesting system will fail to provide a consistent supply of water.
  • Maintenance: A rainwater harvesting system is NOT a set-and-forget system. It will require constant oversight, cleaning, and maintenance. Failure to continuously monitor and clean the system, in fact, may result in a supply of water that’s dangerously unclean and contaminated with impurities.
  • Capacity: Every rainwater harvesting system is obviously limited in the amount of water that can be stored. And systems designed for smaller lawns and landscapes can be quite limited in capacity. During periods of heavy rainfall, it can be frustrating to watch as the system quickly fills to capacity, and all remaining rainfall lost to runoff.

Just One More Tool…

As a global water shortage crisis looms, each method of water conservation deserves consideration. For each individual homeowner, some methods will make more sense than others.

For many, harvesting rainwater will be worthwhile, despite the disadvantages. After all, each gallon of water collected through a rainwater harvesting system can be the equivalent of a gallon of water conserved.

But for most average homeowners, utilizing technological advances like smart irrigation controllers will be at least as effective as conservation tools, and offer less trouble and expense long-term.


Perhaps more important, though, is the mindset of water conservation. Because even if there’s no shortage of water where you live right now, make no mistake: In the long-term, the global water shortage will impact everyone to some degree. And that makes water conservation – regardless of the methods used – the business of every single person.

This entry was posted on Thursday, February 25th, 2016 at 3:50 pm. Both comments and pings are currently closed.

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