New Zealand Journal of Marine and Freshwater Research abstracts

---

Stormwater runoff quality from copper roofing, Auckland, New Zealand

Sarah L. Pennington¹
Jenny G. Webster-Brown^1,2

¹ School of Geology, Geography and Environmental Science
² Department of Chemistry
 University of Auckland
 Private Bag 92019
 Auckland, New Zealand
 email: j.webster@auckland.ac.nz

Abstract Copper (Cu) roofing materials have traditionally been used in New Zealand for institutional roofing, but are now increasingly used on domestic dwellings. The potential contribution to Cu contamination in urban catchment systems was assessed by measuring dissolved and acid-soluble Cu concentrations in the runoff from three full Cu roofs, and one concrete tile roof with Cu guttering, as a function of time during multiple rain events. Full Cu roofs generated runoff with concentrations of up to 7690 µg/litre Cu, predominantly present as dissolved, free Cu2+ owing to the low pH of the rainwater runoff. Runoff from the concrete tile roof with Cu guttering generated up to 590 µg/litre Cu, and the portion of dissolved and free Cu2+ was less owing to the pH buffering effect of the cement-based roofing material. A “first flush” effect was demonstrated in many rain events, where initial runoff had elevated concentrations of both dissolved Cu and particulate Cu, in the form of inorganic Cu minerals and organic Cu-rich aggregate particles.

Keywords first flush; speciation; guttering

New Zealand Journal of Marine and Freshwater Research, 2008, Vol. 42: 99–108
0028–8330/08/4201–0099     © The Royal Society of New Zealand 2008
M07028; Online publication date 11March 2008
Received 1 June 2007; Accepted 30 November 2007

PDF file of entire paper: Print-quality (1318K) | screen-quality (392K)

---

This year's abstracts | Journal home page | All abstracts | Publishing home page