Designing a rain garden to handle all of the runoff from a roof or driveway entails careful calculations.
Is it safe to water a garden with roof runoff.
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.
One exception was zinc and elevated levels could lead to build up of this element in soils.
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.
But you can also learn by experimenting.
Using rain barrels to collect roof water runoff.
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.
At high enough levels this can cause injury to plants and those plants should not be consumed 1.
Steep slopes can however be a good thing for stormwater absorption.
Roof runoff has many outdoor uses.
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.
The untreated runoff quickly killed the salmon while the fish in the rain garden treated water survived.
Asphalt shingles and aluminum hmmm i definitely wouldn t consider drinking that water.
Gardeners often collect water in a rain barrel with little to no protection from the roof s first flush of runoff.
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.
Use it to wash cars and outdoor equipment and to rinse patios.
Also micro organisms can proliferate in the reservoir itself.
Steep slopes can be good for runoff keep in mind the slope of the land while designing your stormwater friendly landscape.
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.
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.
Build one watch what happens after a storm and then enlarge it as needed.