Keeping Rain Barrel Water Clean and Mosquito Free

rain barrelThe rain barrel, an ancient and efficient way of temporarily storing water for those not-so-rainy days or dry spells. Used for irrigating plants and lawns, vegetable and flower gardens, even for washing clothes. They’re also used for drinking water when properly distilled. So, these devices are a great way of cutting down costs and conserving water.

Generally, homeowners install rain barrels under a drain spout connected to a gutter system on their houses. When it rains, the gutters channel the rainwater down through the spout and into the barrel. For areas like ours, where rain is a common occurrence, especially in the summer, these simple collection devices are a smart way to harness the power of nature’s wet nourishment.

Like with most things in life and landscaping, there’s some trade-off for free future irrigation and these particular problems come in two forms: stale, dirty water and disease carrying mosquitoes. When a rain barrel is full, the water begins to stagnate, slowly creating a stench; and, any standing water is quite attractive to the local mosquito population.

Keeping Rain Barrel Water Clean

The reason for rainwater stagnating isn’t the water itself, so-to-speak. It becomes stagnate and “dirty” when organic matter is introduced into it. During a rainstorm, it’s common for a lot of organic matter to be carried by running rain water channeled through a gutter system. Leaves, insects, sticks, and more are all swept away, particularly during a downpour. That’s why most homeowners elect to put a filter of sorts at the end of the downspout, to keep said organic matter out of the water.

Rainwater collection is an age–old technology that has long been used in arid southwestern places such as Texas, Arizona, and New Mexico, as well as states like California and Nevada, where growing populations are stressing limited water supplies. Lately, though, it’s been finding new practitioners even in more well-saturated environs, where rising water bills and dwindling rainfall levels are making homeowners think twice before blasting the tap. —This Old House

By cutting off outside contaminates, it’s possible to keep the rain “fresh” for several weeks, even months. A tightly closed lid and “sealed” system will keep the water free of organic matter; and, hence, no stench. Another trick is to keep the sunlight out. When sunlight hits the water, algae can start to bloom, which is organic, creating the same problem. A small dose of chlorine bleach will keep algae from blooming and will evaporate away in a few days, making it safe for watering plants. A single cup of vinegar or putting charcoal at the bottom will also keep the water clean.

Of course, you should clean it well after use to keep the barrel itself intact. Regular cleaning will prevent things from festering and growing after collecting rainwater and will help to ensure better quality water for your landscaping and gardening needs. Last but not least, if you do have a continual problem with odor emanating from your barrel, it could be the design. Containers with spigots placed too high will collect rain below that line and sit, therefore stagnating, contaminating the entire contents.

Keeping Mosquitoes Away from Your Rain Barrel

Another common problem with a water tank is that any standing water attracts mosquitoes. That’s not good for a number of reasons, the least of which are annoying bites that cause itching. Because these tiny blood thirsty insects breed in and around standing water, a water butt is the perfect place to take-up residence.

To keep mosquitoes away, the barrel should not only be closed-off, but proofed. In other words, don’t leave water lingering on the top, if it’s a truly closed system. Warding off mosquitoes can be done with these three simple, easy to do solutions:

  • Liquid dish soap. Add just one tablespoon once per week or after a storm. By doing this, you’re creating a thin film on the surface of the water. This breaks the surface tension and what that does is drown any mosquitoes that might find their way into the container. They die off before they can lay eggs, but, now you’ve potentially got organic matter that will break down.
  • Mosquito dunks. These contain what’s called “bacillus thuringiensis israelensis” or Bti. You sink one dunk per month or as they are needed and it kills the larvae of mosquitoes and blackflies. It works by dissolving and releasing bacteria.
  • Vegetable oil. A quarter cup of vegetable oil applied weekly or after a storm will do much the same thing as dish soap. The difference here is, the larvae are suffocated by the floating layer of oil.

With these little tips and tricks, you can easily keep your barrel water from stagnating and repel mosquitoes, making it free to use for watering your garden or lawn.

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