If you pay for your water or use a well, you understand the idea of water conservation. There is either a charge for how much water you use, or you draw from an underground water source. No matter which one supplies your main water needs, there are limitations. There is a way to supplement all your water needs by building your own rainwater harvesting system.

A rainwater harvesting system makes use of the precipitation that falls naturally. If you understand what a rainwater harvesting system is and how it works, you can appreciate the amount of free water you can have at your disposal.

What Is a Rainwater Harvesting System?

Gathering rainwater is one of the simplest and oldest ways to generate a self-supply of water. In ancient times, people used to build a water supply for dry periods. The technology to dig wells, or pump water from reservoirs was not available, so freshwater sources such as rivers and lakes were the only source of water other than rainfall. Today there are national organizations that help people harvest water.

The source of rainwater differs depending on the geographical makeup of the area and the structures themselves. Hills and mountains have long been a natural source of water runoff. Roofs of homes and buildings also provide a lot of rainfall runoff. Taking advantage of this water by diverting for irrigation, or collecting it for future use, is the called rainwater harvesting.

How Does It Work?

A rainwater harvesting system works very similarly to a cistern. The different places the system can collect the water dictate how the system works. The easiest type of rainwater harvesting system is a simple serious of canal-like ditches used to divert water into a single holding area. This is only an option for locations where water runs off a hillside. While it is limited by the geographical makeup of the land, it is great for filling ponds, bogs or man-made reservoirs.

However, one can install a rainwater harvesting system in places where the land is absolutely flat. If you have a house, barn, driveway, or any type of structure with a roof, you can use the concept. You take any surface that rainwater falls on or even surfaces where snow lies, and you can put that water to a purposeful use by installing a rainwater harvesting system.

You can treat the water you harvest for drinking purposes in your home or minimally filtered to make it safe for livestock. The primary use for a rainwater harvesting system is to save water for irrigation or to restock groundwater supplies. No matter where you live if you have surfaces where rainwater runs off, you can employ the concept of harvesting this water.

a simple diagram that shows how rainwater is harvested

What Are the Main Components?

Rainwater accumulates as it falls in rivers and on other flat surfaces, even the ground. The parts of a rainwater harvesting system depend on which of these circumstances affect or influence the water collection. If you are diverting water off hillsides or along the gradually sloping ground, you only need to alter the contour of the land to move the water where you want it.

This type of harvesting uses ditches or ravines, with the water collected in ponds or ground-level holding tanks. When the runoff from structures supplies the collected water, one must usually add some containers. Basic plumbing designs, water pipes attached to the ends of gutters or at the end of drains, funnel the water to a holding system.

A rudimentary way to collect rainwater for livestock uses an old bathtub with the drain plugged up. There are tanks made specifically for retaining rainwater. You can add pumps along the pipeline to force the water uphill, or into a home. Large holding tanks use powerful pumps that create enough pressure to power irrigation heads.

It’s true that the most basic system simply funnels rainwater off the roof and into a big holding tank like a small swimming pool. Still, the components for building elaborate rainwater conservation systems are available.

How to Build a Rainwater Harvesting System

To build a rainwater harvesting system that collects water to fill ponds or other types of retaining reservoirs, all you need to do is move dirt. Sometimes, minor alterations to the contour of a hill are enough. They will divert all the water runoff into a holding area.

Step 1

To build a more elaborate system, you can pour concave drainage areas out of concrete, or use a rock with an underlying mat to prevent the ground to absorb the water. For longer storage, or to divert for filtration, you can use a number of simple methods. PVC pipe is the standard item you’ll need to build a rainwater harvesting system.

Step 2

The larger the system, the larger the diameter of the PVC you’ll need. The number places you need to turn the direction of water will determine how many elbows and angled connections you’ll need. One common type of rainwater harvesting system takes rain runoff from rooftops and funnels it to a holding tank. You can use standard gutters, but for ultimate efficiency, a wider gutter will handle more gallons of runoff.

Step 3

All you need to do for a simple tank system is to attach a PVC pipe, usually no less than a 2-inch diameter. Connect them off each downspout, high enough to allow sufficient slope flowing into your holding area. The number and size of rainwater collection tanks vary. You can add massive tanks that hold as much as 1,500 gallons of rainwater. Another way is to use small drum-like containers that resemble normal sized garbage cans.

Step 4

Some people get inventive and build their own tanks of recycled bladder tanks, above-ground swimming pools or standard 100-gallon drums. What you plan to use the water for, and how much you want to store will dictate this part of your project. The ecological mindset of the world is continually growing towards a focus on water conservation.

So much water comes naturally from rain and snowfall that wasting this source is inefficient environmentally. The idea of building a rainwater harvesting system is even more important in areas with limited access to fresh water.

By using sound rainwater collection practices, dry and arid climates make use of limited annual rainfall. Building a simple rainwater collection setup is easy. To design an elaborate rainwater harvesting system, there are professional experts who can help you with planning and materials.

Bottom Line

What you need to do today, is assess how much water you watch go wasted as it runs off down the sewer drain. This water could reduce your monthly bill, plus ease the strain on underground supplies. Most of all, it will help move our world towards a better sense of water conservation.

Image sources: 1, 2