Rainwater Catchment

Rainwater harvesting is an environmentally friendly way of collecting water for a wide variety of purposes, including watering the garden, doing laundry, flushing toilets, and even drinking. Much of an average household’s water needs can be met by collecting rainwater without worrying about treating the water. However, if the goal is to drink the water, proper treatment is crucial.

Rainwater Contaminants

In theory, rainwater should be an excellent source of clean water; however, this isn’t necessarily the case.

Increasing levels of carbon dioxide in our atmosphere reduces the pH of rainwater. With a lower pH, rainwater will be aggressive in dissolving various contaminants from collection systems (roof, eaves trough, etc.). This acidic water can have negative impacts on copper piping and metal fixtures in the home.

E. coli, giardia, and cryptosporidium can also contaminate rainwater when it comes into contact with animal droppings—for example, bird or raccoon droppings on the roof. Water contaminated by these microorganisms must be properly treated before being consumed.

Rainwater Storage

Extra attention must be paid to the storage of the collected water. Turbidity from debris (leaves, dirt particles) as well as taste and odors may occur when catchment is improperly stored. Exposure to the elements could also increase the odds of contamination, which can be worsened by elevated temperatures during storage.

While rainwater harvesting is a common and effective method for collecting a water supply, it’s important to test the water and implement appropriate water treatment, depending on its intended use.