So roof runoff is not considered safe for human consumption in most countries at least not without filtration.
Is it safe to water a garden with roof runoff.
The untreated runoff quickly killed the salmon while the fish in the rain garden treated water survived.
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.
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.
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.
Also micro organisms can proliferate in the reservoir itself.
Unless the zinc content is particularly high it is safe to use on lawns and ornamental gardens.
Use it to wash cars and outdoor equipment and to rinse patios.
One exception was zinc and elevated levels could lead to build up of this element in soils.
But you can also learn by experimenting.
If your property slopes toward any buildings you will want to divert that water.
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.
Using rain barrels to collect roof water runoff.
Designing a rain garden to handle all of the runoff from a roof or driveway entails careful calculations.
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.
At high enough levels this can cause injury to plants and those plants should not be consumed 1.
Asphalt shingles and aluminum hmmm i definitely wouldn t consider drinking that water.
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.
Roof runoff has many outdoor uses.
Limited studies have been conducted focusing on the safety of roof runoff for vegetable garden irrigation.
So roof runoff is not considered safe for human consumption in most countries at least not without filtration.
Build one watch what happens after a storm and then enlarge it as needed.
Gardeners often collect water in a rain barrel with little to no protection from the roof s first flush of runoff.