RAINWATER HARVESTING METHODS
Rainwater harvesting, which is the process of collecting and storing water from catchment areas such as roofs, rock surfaces and hilly areas, can be done in several ways. The method of choice for this process is determined by several factors including frequency and quantity of rain, end users, funds and resources available and the characteristics of the catchment medium.
Climate change, increasing demand for water and rising costs of water supply are making rainwater harvesting increasingly important, and it therefore behooves anyone interested in finding a consistent and sustainable source of water to consider using this simple and affordable process to solve their water supply problems. The following are the most common methods used to harvest rainwater, from systems that utilize the most basic techniques and equipment, to those that require considerable capital outlay and expert advice.
Groundwater recharge occurs when rain and surface runoff enter the soil and are stored by soil and other man made media for future use. It is becoming increasingly important due to falling levels of water supply from boreholes and wells in urban areas which utilize groundwater sources without any way of replenishing this dwindling supply. Groundwater recharge replaces lost sources of water with rainwater runoff to reverse the effects of overexploitation.
There are several methods to recharge underground water sources including:
- Sand dams
- Re-used plastic barrels
- Direct recharge of wells and boreholes
Roof water harvesting
Roof water harvesting involves collecting rainfall from roofs and storing it in jars, tanks or barrels. The amount of water stored is determined by the size and shape of the roof. The roof water collecting system has 3 basic components i.e. collection surface, conveyancing system and storage facility. The collection surface is typically the roof of a building; the conveyancing system refers to the gutters and pipes that deliver the water into the storage vessels which may be tanks, barrels or cisterns.
Surface runoff harvesting
Surface runoff harvesting uses man made systems to collect rainwater runoff from surfaces such as roads, hills, trenches and others and divert it into both natural and manmade storage systems like dams, ponds, underground reservoirs, streams and rivers. All water collected in this way must be treated and conserved properly in order to make it safe for various purposes including human and livestock consumption, irrigation of crops and household purposes such as general cleaning and laundry.
Rainwater harvesting is a simple and affordable way for people to meet their water needs while helping to conserve valuable water resources in the face of increasing global demand. Whatever your needs are, there is a method to suit your budget and living circumstances, and anyone who is looking for a sustainable water supply method would do well to consider rainwater harvesting. Want to learn more about the incredible methods you can use to harvest rainwater? The Open Permaculture School and on Regenerative Leadership Institute page you can find all the courses you need to make a start.