It’s never, ever maintained properly and the inlets or “permeable” pavement gets plugged up and effectively gets turned into 100% IC almost every installation. My last city’s engineering team went from encouraging it to recommending it be banned when they saw what happens when it isn’t maintained.
There’s some pervious asphalt at my office that has over 10 years of fines in it and infiltrates <1”/hr. If you hit it with a vacuum it quickly clears to >50”/hr.
It’s never, ever maintained properly and the inlets or “permeable” pavement gets plugged up and effectively gets turned into 100% IC almost every installation. My last city’s engineering team went from encouraging it to recommending it be banned when they saw what happens when it isn’t maintained.
There’s some pervious asphalt at my office that has over 10 years of fines in it and infiltrates <1”/hr. If you hit it with a vacuum it quickly clears to >50”/hr.