Even if you live in areas with low rainfall, you can harvest large amounts of rainwater.
It’s raining out. The water is running off the roof, through gutters, and onto the ground. From there, it seeks out lowest areas. This could be streets in urban and suburban areas, streams and ditches in rural areas.
Eventually the water feeds into larger streams, rivers and finally into the sea. In arid areas, water cascading from roofs may cause erosion,forming arroyos and ravines in the sandy soil, and then dissipate, evaporating or sinking into the ground far away from where it is needed.
Even in extremely arid areas (a region receiving less than 15 inches a year), thousands of gallons of rainwater and melting snow run off roofs, sidewalks, patios and other surfaces every year. Unless collected in some form, this water is lost to the homeowner and gardener. Here are some methods that the gardener can use to salvage some of this resource.
Rainwater Gardens
One of the easiest methods for capturing and using rainwater is a rainwater garden. Rainwater gardens can be simply a concave “dish” carved into the soil, or elaborate systems using dry streambeds and small collection basins. This water is generally used where it collects, watering plants along its path.
Use Native Plants
Gardeners have a tendency to plant anything that looks nice. However, many plants that “look nice” may not be suitable for the specific area. Native plants, on the other hand, are adapted to the rainfall of the area. In other words, they can survive on available rainfall alone.
Storing Rainwater
Before the development of public water systems, many people in America and elsewhere obtained their water from harvested rainwater.
This process can be as simple as collecting rainwater in a barrel. It can be as complex as the use of multiple tanks, pumps, valves and distribution systems.
For instance, a 55-gallon drum (with a hose attachment and spigot at the bottom) can simply be placed under a downspout. Gravity feeds the water to where it is needed. Or water can be fed through a gutter system into large tanks holding thousands of gallons of water.
Rainwater Harvesting Suppliers
There are many suppliers offering tanks of varying sizes, ranging in prices from several hundred to several thousand dollars. Most of these tanks are made of heavy-duty polyurethane, although some are made of steel.
Treating Rainwater
If the water is used solely for irrigation, no treatment is needed. However, if it is for household use, then there are treatment systems available at varying costs. Generally these systems include ultraviolet and reverse osmosis treatments.
There are varieties of other attachments and gizmos, which can be used in rainwater harvesting systems. Solar-powered mechanisms can open and close valves at specific times, allowing irrigation without constant supervision. Roof-mounted solar-powered rain sensors monitor precipitation. It can then adjust irrigation timers accordingly. There are virtually no regulations (except perhaps cosmetic rules in subdivisions) that prevent rainwater from being collected and used by householders for outdoor use.
However, there are generally regulations in place in most areas that require permits for indoor uses of rainwater (like flushing toilets, showers, washing clothes, etc.). These rules also require complete separation between the public water system and the rainwater system. This is to prevent possibly contaminated rainwater from backing up into the public system. If the harvested rainwater is to be used for drinking water, then there are much stricter regulations.
