Is It Safe To Water A Garden With Roof Runoff

Locate a rain garden at least 10 feet from your house and at least four times that far from a septic system or steep slope.

Is it safe to water a garden with roof runoff.

Roof runoff has many outdoor uses. So roof runoff is not considered safe for human consumption in most countries at least not without filtration. Curiously in other countries the inhabitants are not so squeamish and roof runoff water is their main source of drinking water soil microbes and root hairs carefully filter materials entering the roots. But could the runoff water contain harmful elements or chemicals that are leached from the roof and pose a hazard to plant life or even be capable of contaminating garden soil and crops grown for food.

To store as much rainfall as possible in your garden soil you can set up a rainwater irrigation system that diverts your roof runoff water directly onto your garden beds or lawn if you prefer. Steep slopes can be good for runoff keep in mind the slope of the land while designing your stormwater friendly landscape. Steep slopes can however be a good thing for stormwater absorption. One exception was zinc and elevated levels could lead to build up of this element in soils.

Also micro organisms can proliferate in the reservoir itself. Using rain barrels to collect roof water runoff. But you can also learn by experimenting. Build one watch what happens after a storm and then enlarge it as needed.

The water flowing from a roof does pick up a small quantity of contaminants including chemicals from shingles and gutters possibly bird and animal waste tannins and other compounds from leaves in the gutter etc. In one study most of the metals tested the same in rain barrel water as in rain water before it hit the roofs so little to no concern there. Asphalt shingles and aluminum hmmm i definitely wouldn t consider drinking that water. So roof runoff is not considered safe for human consumption in most countries at least not without filtration.

So watering the soil instead of pouring it directly on the veggies provides an opportunity for the soil to work some of its purifying magic before the water is taken up by the plants. Designing a rain garden to handle all of the runoff from a roof or driveway entails careful calculations. At high enough levels this can cause injury to plants and those plants should not be consumed 1. Limited studies have been conducted focusing on the safety of roof runoff for vegetable garden irrigation.

Unless the zinc content is particularly high it is safe to use on lawns and ornamental gardens. Gardeners often collect water in a rain barrel with little to no protection from the roof s first flush of runoff.