Author: Scott Mouw
For gardeners or anyone interested in water conservation, rain barrels are essential. These barrels allow homeowners to collect rainwater from a roof to use as an alternative water supply in place of groundwater. Most rain barrels have a closed top to help control mosquitoes and keep out extraneous materials, but I have always had an open-top barrel with a spigot to be able to dip water out for quick trips to vegetable and flower gardens.
As I quickly found out when I set up my barrel, mosquitos will definitely find it. So how do you control mosquitoes with an open barrel? After trying a number of methods, I decided to follow nature’s example and use fish.
Goldfish in particular have proven hardy in withstanding the harsh conditions of a rain barrel. The very small, cheap varieties available in any pet store can grow to four inches in length and live five years or more. They can even survive through a cold winter and nights where three inches of ice forms on the surface, more or less hibernating at the bottom of the barrel.
And goldfish certainly do the job of mosquito control. For a time, I had two barrels where I experimented with fish in one and none in the other. In the barrel without fish, mosquito larva quickly became well established. But in the barrel with fish, the water was super clean, a sign that the fish were eating well.
Open rain barrels are not for everyone and there are some downsides. For example, having fish means you can never use all the water in the barrel. But regardless of whether it is open or closed, the main point is to get a barrel to reduce the use of city water for outdoor watering. There are at least two local suppliers of rain barrels in Raleigh; Rain Barrels International and Rainwater Solutions, and a quick Google search can uncover other sources. Rainwater Solutions sells rain barrels made in part from recycled plastic from milk jugs and laundry detergent bottles (HDPE #2), processed by Blow Molded Solutions in Mayodan. Yet another good reason to recycle your plastic bottles!
Scott Mouw, is the outgoing Section Chief for Recycling and Materials Management in the Division of Environmental Assistance and Customer Service of the N.C. Department of Environmental quality. Scott has been with the State for more than 24 years and has led grant and assistance programs to expand material collection and processing efforts that provide vital feedstocks to manufacturers in North Carolina and around the world. He has focused on increasing public access to efficient, comprehensive local recycling services as well as expanding and streamlining the state's recycling economy. Scott has also been involved in crafting and implementing policies and engaging in many regional and national dialogues to help support increased material recovery. On February 28, 2017, he will be retiring from NCDEQ to go to work on a part-time basis with The Recycling Partnership, a national non-profit dedicated to improving the U.S. recycling system.