Water is one of our most precious resources, and the available amount is dwindling every day.  Texas is actively promoting water conservation including rainwater catchment due to anticipated shortages.  Rainwater catchment is an alternative to using up ground water.  It's also good for the environment.

Rainwater catchment or rainwater harvesting is the collection and storage of rainwater from roofs.  It operates on a simple principle of containing and using rainwater near where it falls thus using less energy than municipal water systems and wells.

Using rainwater was at one time a traditional practice in the United States and is in use throughout the world. It has been estimated that there are about 250,000 rainwater collection systems in the United States. Many people in Australia, New Zealand and some Caribbean islands depend entirely on rainwater harvesting for their water needs.

The costs of rainwater collection are largely set-up costs - the water is essentially free. If your current water source is a well or a public utility, your costs will increase as surface and ground water become more scarce and energy costs rise.  When using a public water system, you may be affected by restrictions during drought conditions. With a rainwater harvesting system, you control how much water you use and when you use it.

Installing a rainwater harvesting system costs about the same as drilling a well, but it requires less maintenance and energy than using groundwater.  Municipal and well water requires more chemical treatment than naturally soft rainwater.  Rainwater tastes better and is better for your plants and appliances.

Rainwater harvesting systems come in many shapes and sizes. They can serve both potable (i.e. drinking) and non-potable needs. Click on this link to see several rainwater harvesting systems and the different types of tanks that can be used. Click on this link to learn about wet and dry rainwater harvesting systems.

Here is a simple schematic showing one of the ways rainwater is collected and stored.

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Rain landing on the roof and is captured in the gutter. From there the water flows into a small filtering barrel called a roof washer. The inlet of the roof washer has a filter that removes leaves and other debris. Filtered water then flows through an underground pipe leading to the storage tank. There are other filtering mechanisms, such as first flushes and sock filters and other pipe configurations that can be used.

Most larger systems collect water from multiple downspouts and are custom-designed to suit to the specific catchment area, site location, and water end-use.