As a horticulturist for 25 years, I believe in the benefits of organic gardening for myself and my clients whether for fruits, vegetables or flowers. No one who has gardened with organics would argue the benefits.
My personal garden has been pesticide free for 17 years. The insect populations of predators and prey reached a balance after about 3 years. Since that time, I have observed a substantial reduction in the insect populations. Weeds will always be a problem but the loose organic soil makes them easy to pull. Our organic garden has afforded me and my family the piece of mind to walk on the lawn in bare feet and eat vegetables right from the garden.
That being said, I have another area of my environment that concerns me. I design and manufacture a rainwater harvesting system called The Original Rainwater Pillow. This business venture has required a deep study of water. I am often asked “Why should we harvest rainwater in areas where water is plentiful?” The fact is the more developed an area is, the more pollution there will be in the water sources. Impervious surfaces create storm water run-off that pollutes our ground water, streams and rivers. Rain is the cleanest water on earth before it touches a surface, but once it hits an impervious surface it washes the surface of debris and dumps the pollutants into our drinking water sources.
Atlanta and the surrounding metropolitan areas require over 500 million gallons of fresh water per day.(1) Most of the water is supplied from surface water (rivers and reservoir) and requires extensive treatment to insure that it meets EPA standards before it reaches the tap. The incredible quantity of water required daily impedes the municipal water treatment system’s ability to removal a variety of pollutants in our drinking water. It is well cited that these pollutants are on a very small scale and should have no affect on a healthy individual. Some of the common pollutants are pharmaceutical drugs(2)and a long list of industrial chemicals(3). These chemicals mainly enter our water system through storm water run-off and raw sewage overflow creating challenges for Atlanta’s water quality.
My concern with using municipal water in organic vegetable gardening is the fact that plants are basically water filters. As a plant grows it absorbs water and pollutants. It then transpires pure H2O into the atmosphere and the pollutants collect in the plant tissues. This filtering continues as long as the plant grows. The older the plant are the more pollutants present in the plants tissue. The efficiency of absorption varies with plant species and the size of the molecules of the pollutants.(4)
The premise of growing vegetables organically is to produce the cleanest healthiest vegetables possible. But irrigating with municipal water and it’s associated pollutants reduces the quality of the organic produce. The degree of contamination is dependent on many factors but the biggest issue is that we have no idea what the pollutants are and how they will affect us over long periods of time. It could be many years before we know or understand the long term affects of the chemical accumulation of pollutants in our drinking water and in our organic gardens. Our bodies might simply not be affected or evolve to assimilate these pollutants. But the fact remains that pollutants in our produce are measurable and steps should be taken to reduce or eliminate these pollutants.
The easiest way to overcome this issue is to collect rainwater. Water that falls from the sky has been pre-filtered thus making rainwater the cleanest water on earth. A well designed rainwater harvesting system will provide the highest quality water for potable and non-potable uses. The first consideration in selecting a rainwater harvesting system is to determine where and how you are going to store the water. A large variety of different catchment vessels are available from pillows to in ground cistern to various shapes of above ground tank. The size of a system is based on your collection potential (average annual rainfall ) and your water use needs. The other necessary components of a rainwater harvesting system include a collection area(usually a roof), a pre-filter prior to storage and a pump. For potable water systems, minor additional filters and UV light can provide the cleanest drinking water readily available.
Rainwater harvesting is a proven technology with the direct benefits of source point collection and use, which almost eliminates the energy cost necessary to provide water from any other source. Equally as important is the benefit of reducing storm water run off which is polluting other water resources. Rainwater Harvesting is one more option available to make our organic gardens simply more organic.