Although water may seem like a boundless resource, it is far from it. Only 2.5 percent of the planet’s water is fresh, and 74 percent of that is tied up in the polar icecaps. Groundwater accounts for another 25 percent, leaving just 1 percent of freshwater to be found in lakes, rivers, soil, and air. Due to population growth, drought, and pollution, groundwater resources are seriously declining. Today the world fights over oil; tomorrow (if not already) it will fight over water.

Gardeners can play a key role in conserving freshwater by harvesting rainwater. In addition to reducing demand on our water supplies—especially important during drought and summer (when 40 percent of all water is used outdoors)—rainwater harvesting reduces water pollution. In a rainstorm, oil, pesticides, animal waste, and fertilizers from our lawns, sidewalks, driveways, and streets are washed into sewers that often overflow into rivers and estuaries, contaminating fish and other wildlife. Rainwater harvesting prevents rain from becoming polluted stormwater and puts it to use where it falls.

The quality of rainwater is unsurpassed when it comes to watering plants and landscapes. Captured rainwater is free of the salts and pollutants associated with ground and surface water. In urban areas, the natural acidity of rainwater is good for soils that have become alkaline from cement-leached lime. The natural temperature of rainwater doesn’t shock plants with cold the way tap water can. Best of all, rainwater contains no chlorine, a chemical added to drinking water that inhibits plant growth. And rainwater is free!

Designing a Rainwater Harvesting System

Regardless of how much rain your area gets or how big your landscape is, you can design a rainwater harvesting system that works for you. The most common method of capturing rainwater for irrigation involves taking rain from building gutters and storing it in an outdoor tank .

“It isn’t easy to come up with ‘one size fits all’ instructions for building rainwater harvesting systems because of variations in styles of roofs, downspouts, storage tanks, and garden layouts. You have to use a combination of research, common sense, ingenuity, and dumb luck to design and build your system.”

Ideally, rainwater harvesting systems for irrigation include five basic components:

• Catchment or collection area—usually a roof;
• Transport for the water, such as gutters, downspouts, and piping;
• Roof washer to intercept the first flush of rain (plus any debris or bird feces) from the roof—usually a sealed downspout next to the main downspout;
• Storage tank ;
• Gravity- or pump-driven system for distributing water to the garden.

Bear in mind that only non potable usage of rainwater is described here; harvesting rainwater for drinking involves several levels of filtration as well as chemicals for disinfection.

For a free no-obligation consultation on how you could benefit from rainwater harvesting contact us