Urban Stormwater Runoff Contamination Associated with Gutter and

Urban Stormwater Runoff Contamination Associated with Gutter and Pipe Material Use Olga Ogburn 1 and Robert Pitt 2 1 Graduate Student; Civil, Construction, and Environmental Engineering Department; The University of Alabama 2 Ph. D. , P. E. , BCEE, D. WRE Cudworth Professor of Urban Water Systems; The University of Alabama http: //www. slatetileroofing. com/gallery/images/allred_roof_systems_gallery/copper_gutters. jpg

The Goal q. To determine how stormwater quality is affected by the type of gutter and pipe materials, environmental parameters causing degradation of the material, time of contact, and interactions of those factors.

Prior Research q Contribution of rooftop material to runoff water quality, for example: – Zinc concentrations from uncoated galvanized metal ranged between 3. 5 and 9. 8 mg/L (Clark, Long et al. , 2008). – Zinc concentrations from coated galvanized metal were below 0. 5 mg/L (Clark, Long et al. , 2008). q Effect of pipe material and environmental parameters on drinking water quality, for example: – Iron concentration from PVC pipes reached 0. 058 mg/L after 3 days of exposure (Lasheen M. R. , Sharaby, C. M. , et. al, 2008).

Experimental Design q. A series of long-term static leaching tests q. Eight roof and pipe materials q. Low and high p. H condition q. Natural storm water was collected in the city of Tuscaloosa from downspouts and from storm drain inlets.

Materials: q. Gutter Materials: vinyl, aluminum, copper, and galvanized steel. q. Pipe Materials: concrete, HDPE, PVC, and galvanized steel. q. New materials q. Concrete pipes - 15 cm long q. The rest of pipes - 30 cm long

Experimental Design q Containers with p. H values of 5 and 8 (using Na 2 HPO 4 * 2 H 2 O and KH 2 PO 4 to create buffers) q Sampling times: time zero, 0. 5 hr, 1 hr, 27 hr, 1 mo, 2 mo, 3 mo Measured Parameters: q Metals (cadmium, chromium, lead, copper, zinc, aluminum, and iron) q Toxicity (Microtox) q p. H q Nutrients (ammonia nitrogen, total nitrogen, nitrate) and COD

Mass Release per Surface Area, mg/m 2 Lead Mass Release per Surface Area of a Pipe/Gutter in Containers with p. H 5 and p. H 8 100 10 P. Steel p. H 5 G. Steel p. H 5 0. 001 0. 1 Time, day 1 P. Steel p. H 8 1 10 0 q Lead release was observed only for galvanized steel materials during both short and long exposure times. q The loss of lead was higher for containers with p. H 8 compared to containers with p. H 5. q The highest lead release was noted for galvanized steel pipe at p. H 8 and was between 0. 628 – 0. 710 mg/L (corresponds to 25 - 30 mg/m 2). G. Steel p. H 8

Time, day Mass Release per Surface Area, mg/m 2

Mass Release per Surface Area, mg/m 2 Time, day

Mass per Surface Area, mg/m 2 Time, day

Mass Release per Surface Area, mg/m 2 Time, day

Concrete and Galvanized Steel Materials Concrete Pipes at 3 mo 0, 12 Total Metal Concentration, mg/L §No metals were detected with concrete pipes until 2 months 0, 10 0, 08 p. H 5 0, 06 p. H 8 0, 04 0, 02 0, 00 Lead Zinc Aluminum Iron Steel Gutters at 3 mo 16 16 14 14 12 10 p. H 5 8 p. H 8 6 4 2 Total Metal Concentration, mg/L Steel Gutters at 27 hrs Copper 12 10 p. H 5 8 p. H 8 6 4 2 0 0 Lead Copper Zinc Aluminum Iron

Aluminum and Copper Materials Aluminum Gutters at 27 hrs Aluminum Gutters at 3 mo 0, 020 0, 015 p. H 5 0, 010 p. H 8 0, 005 Total Metal Concentration, mg/L 0, 45 Total Metal Concentration, mg/L 0, 025 0, 000 0, 40 0, 35 0, 30 0, 25 p. H 5 0, 20 p. H 8 0, 15 0, 10 0, 05 0, 00 Lead Copper Zinc Lead Copper Gutters at 27 hrs Zinc Aluminum Iron Copper Gutters at 3 mo 6 7 6 5 p. H 5 4 p. H 8 3 2 1 0 Total Metal Concentration, mg/L 8 Total Metal Concentration, mg/L Copper 5 4 p. H 5 3 p. H 8 2 1 0 Lead Copper Zinc Aluminum Iron

Toxicity Gutters p. H 8 @ 5 min q At higher p. H conditions 80 % Effect q. Concrete and Vinyl materials – least toxic q. Copper and PVC – most toxic 100 0, 01 G. Aluminum p. H 8 60 G. Aluminum p. H 8 40 G. Copper p. H 8 20 G. Copper p. H 8 G. Steel p. H 8 0 0, 1 -20 1 10 10000 G. Vinyl p. H 8 -40 100 80 8 P. PVC 7 P. HDPE 60 P. Concrete p. H 8 6 P. Steel 40 P. HDPE p. H 8 5 G. Vinyl 20 P. HDPE p. H 8 4 G. Aluminum 3 G. Steel 2 G. Copper 1 1 10 Time, hr 10000 P. Concrete % Effect p. H, unitless 9 0, 1 Time, hr Pipes p. H 8 @ 5 min 10 0, 01 G. Vinyl p. H 8 -60 p. H measurements for containers with p. H 8 G. Steel p. H 8 0, 01 P. Concrete p. H 8 P. PVC p. H 8 0 0, 1 -20 1 10 10000 P. PVC p. H 8 P. Steel p. H 8 -40 -60 100 P. Steel p. H 8 Time, hr

Conclusions q. The greatest source of lead, zinc, and iron were galvanized steel materials, while copper materials were the highest source of copper. q. Lead and Zinc release was detected during both short and long exposure. q. During short exposure time copper releases were detected only for copper materials at both low and high p. H q. Copper and aluminum materials had the highest toxicity, while concrete materials were least toxic.

References § Clark, Shirley E. , Long Brett V. , Siu Christina Y. S. , Spicher Julia, Steele Kelly A. , 2008 Runoff Quality from Roofing during Early Life. Water Environment Federation. § Lasheen M. R. , C. M. Sharaby, N. G. El-Kholy, I. Y. Elsherif, S. T. El-Wakeel, 2008. Factors influencing lead and iron release from some Egyptian drinking water pipes. Journal of Hazardous Materials. 160 (2008) 675 -680 § http: //www. slatetileroofing. com/gallery/images/allred_roof_systems_gall ery/copper_gutters. jpg § http: //www. guttersupply. com/file_area/public/categories/Image. Url_1202 397996_9640. jpg Acknowledgements § NSF EPSCo. R

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