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Water Harvesting

catch the rain Water harvesting is the capture, diversion and storage of rainwater for plant irrigation and other uses. It is appropriate for large scale landscapes such as parking lots, parks, apartment complexes, schools and many other commercial uses. It is just as practical for small residential yards as well.

Many different methods are used for water harvesting. Some of them can be very inexpensive and easy to do. Storage containers, large and small, or used in water harvesting, as are berms and canals.

Why should you harvest water?

Water harvesting can reduce your normal water use and can be used to control flooding and erosion.
It is possible to direct water to areas best suited for allowing it to return to the water table.
Plants love rainwater. Not only do the plants love this salt-free water, your soil does to. There is no better way to water your plants than with using good ole rain water.

Rainwater can be harvested for immediate use, or stored and used as needed. If you are just starting out with water harvesting I suggest directing the water for immediate use to start with. When you have done all you can in that aspect and still have left over water, then by all means, store it.

Using rain water means getting it to the plants in an easy, and automatic, fashion. One bucket at a time, during a rain storm, is not the way we want to do it. Simple water system designs use gravity to move the water to where it can be used. The area where the water is collected from is called the catchment area. A catchment area is normally a rooftop, a paved area or possibly an area in your yard. The best catchment areas are hard smooth surfaces.

The distribution system connects the catchment area to the landscape holding area. Distribution systems direct the flow of water and can be of a very simple nature, or in some cases, quite elaborate. Examples of distribution systems include :

Gutters and downspouts
Sloped sidewalks and driveways
Hillsides and sloped yards
Channels and ditches are used to move water
Piping such as PVC pipe is commonly used

The roof of your home will probably be your biggest source of rain water, so let's take a look at some ways to properly harvest this water. Rain gutters are the most common distribution systems for harvesting roof water. The water can be captured from the roof and directed to your plants in many different ways.

One of the easiest ways is to run the water directly into a landscape holding area. This would consist of a concave area with some type of edging to retain the water. The water is then immediately used for watering the plants.

Channels and pipes can be used as part of the distribution system. The water coming out of downspouts can go directly into a channel and taken to landscape holding areas containing plants.

Landscape holding areas can be easily created by digging out some dirt, creating a low spot. This dirt can then be used to build berms, moats and possibly terraces. With proper design your holding areas can overflow and run from one to the next.

French drains are holes, or trenches, filled with gravel. They can be an excellent way of channeling water from one holding are to the next. French drains, or underground landscape pipes, are ways to distribute the harvested rainwater in an invisible manor.

rain water Your objective with a simple, gravity fed, harvesting design is to get the water from your roof to your plants. Before you start digging observe your yard during a rain. See where the water goes, find the low spots and the high areas. Determine if you have areas that would be adequate holding areas or would you need to create one, or several. If you have existing plants in areas you want to hold water consider building berms around these areas as apposed to digging down and possibly damaging the roots. Holding areas should extend beyond the drip line of existing plants, whenever possible.

After your simple water harvesting system has been in use for a while begin to monitor your water use. Are you still needing to water your plants with tap water? Is this water use more than you would like it to be? If so, you may need to go to the next step and get involved in a complex water harvesting system.