But there’s also water quality and flooding issues associated with using all available land for building.
Grass and dirt absorb water. Rooftops and concrete don’t. 1-inch of rain on an acre of grass will be absorbed. Replace that grass with impervious cover and you’ve got an extra 27,000 gallons of water, or about 2 swimming pool’s worth of runoff.
Grass has an extremely low runoff coefficient. The water absorption is almost on par with impervious surfaces. This is because the root system of most turf/gras systems is only a few inches deep. On the other hand native grasses, fescues, and trees are excellent for water infiltration! Rain gardens are also good choices as they promote pollinators. I’m a landscape architect --happy to answer any questions.
Errata: meant to say high runoff coefficient --not low.
the only good lawn is a flood management lawn, there’s two notable ones in my town and they literally turn into marshes when it’s been raining a lot or the water level is high, and without them entire areas would flood.
Yes, lawns are wasteful.
But there’s also water quality and flooding issues associated with using all available land for building.
Grass and dirt absorb water. Rooftops and concrete don’t. 1-inch of rain on an acre of grass will be absorbed. Replace that grass with impervious cover and you’ve got an extra 27,000 gallons of water, or about 2 swimming pool’s worth of runoff.
Grass has an extremely low runoff coefficient. The water absorption is almost on par with impervious surfaces. This is because the root system of most turf/gras systems is only a few inches deep. On the other hand native grasses, fescues, and trees are excellent for water infiltration! Rain gardens are also good choices as they promote pollinators. I’m a landscape architect --happy to answer any questions.
Errata: meant to say high runoff coefficient --not low.
Low runoff coefficient means more absorption and less runoff, even sod typically has a C of around 0.3, as opposed to the 0.95 of concrete.
I agree more natural landscaping is better!
Good catch. Still, very low infiltration compared to native grasses. I have the papers on it parked somewhere.
That’s what public parks and other green spaces are for.
the only good lawn is a flood management lawn, there’s two notable ones in my town and they literally turn into marshes when it’s been raining a lot or the water level is high, and without them entire areas would flood.