Somehow I missed this the first time by, but it's definitely worth mention, even if it is 2 years old.
When it came to the pollutant removal efficiency of pervious concrete, all we really had to cite was this table:
The Stormwater Center at the University of New Hampshire, however, has published their data in a new table, and it shows just how good pervious concrete is in pollutant removal efficiency. Page 11 is the highlight.
The report also discusses the practice of sealcoating asphalt parking lots and the impact on downstream water quality, "Although it is intended to remain on the pavement surface, UNHSC researchers found that much of the sealcoat flakes and then washes off during storm events, ending up in nearby streams and stormwater treatment devices. ...UNHSC field data shows that just nine months after sealing only 4 percent of the entire parking lot area, PAH levels increased in the swale receiving runoff from the entire lot to 95.7 mg/kg, double the regulatory limit of 44.7 mg/kg." That's a 60-fold increase in Total PAH from pre sealant levels!
Also of interest, are their practical notes on how well pervious concrete performed through the tough New Hampshire winter, "While the pavement froze sooner, deeper, and for longer periods than the reference condition, the pores remained open and well-drained year round." The authors also included some new recommendations for winter maintenance on page 17.