The Essentials of Rainwater Harvesting

The idea behind rainwater harvesting is pretty simple: rain falls, it is collected, stored and used at a later date. With the advent of new technology, new filters and purification systems, there is a great opportunity for wide-spread daily application of rainwater harvesting. Not only is it used as a sustainable way of irrigation, but it is also used in industry, as well as for our daily needs at home. To truly understand how it all comes together, here is the essential lowdown on rainwater harvesting.

Where to Collect

Collecting rainwater can be achieved from almost any surface, but roofs are by far the best catchment option. Roofs turnout the largest amount of quality water in an efficient and cost-effective way. The quality of water, however, depends on the type of roofing material, and the amount of debris. Inert roofing materials, like terra cotta and stone tiles, and elastomeric membranes, together with a pre-filtration system, churn out water that is fit for irrigation and external usage. Suitable filtration and a post treatment system are a necessity when collecting rainwater for internal use, like drinking, and washing.

How to Harvest

The actual harvesting process of rainwater depends on the transfer system. The water is transferred to the usual drainage installations of your facility. The most cost-effective harvesting systems use available gutters and downspouts to collect rain into a container. With an addition of a gutter cap system, they also serve as pre-filtration, which can reduce maintenance costs.

Storage Considerations

When harvesting rainwater, you need strong and capacious water cartage tanks, which are able to store large amounts of water. These containers can range from 55 gallons to 10,000 gallons, but all of them need to be structurally strong in order to support the weight of the water. To maximize efficiency, the downspout needs to be directed to a central location, where the cartage tanks are placed. However, the tanks should never be placed near utility services or septic tanks, as not to contaminate the water.

How to Make Rainwater Fit for Drinking

Before you are able to drink water from a water harvest tank, it first needs to pass through several levels of filtration. The first one is the pre-filtration system which gets rid of the largest debris before exiting the downspout. Before entering the storage unit, it passes through a second, finer filter, which further cleans the water of contaminants. The final step includes a chemical, filtration treatment. Even though it goes through the filtration system, you should always measure and inspect the quality of water before using it.

Key Benefits

The advantages of rainwater harvesting are numerous. In places like India, rainwater is propagated as the best alternative to ground-water irrigation, aiding farmers during dry seasons. Both in agriculture and industry, it provides access to an available and regulated water supply that is more cost effective and better for the environment than other, more conventional sources. Depending on the size of your home and storage tank, rainwater can also provide you with enough water to supply your annual demand at home, as well. Although the initial investment comes at a big cost, the later filtration and maintenance costs are only a fraction of the conventional method of water supply.

In the end, we need to remember that, for a long time, people have been collecting rainwater in areas of the world where water was scarce. Only now, when we are constantly reminded of our impact on the planet, do we realize its full potential. Providing us with a sustainable and renewable supply of water that can minimize our environmental footprint for a fraction of the cost of alternative sources, harvesting rainwater is a smart and conscious choice to make.

Guest Contributor, Lillian Connors