The effect of roofing material on the quality of harvested rainwater

Quality and seasonal variation of rainwater harvested from concrete, asphalt, ceramic tile and green roofs in Chongqing, China

“…In conclusion, the concrete roof contains lots of alkaline substances and metals. Therefore, the mean pH of the concrete roof was significantly higher than the other roofs, mainly because of the alkaline nature of the concrete, which is consistent with other studies (Mendez et al, 2011). On the concrete roof, the mean concentration of TSS was significantly higher than the other roofing material samples.…”

“…In our study, the mean concentrations of TOC and Zn(aq) from the asphalt roof were significantly higher than the concrete and ceramic tile roofs, and the mean concentrations of TN, COD and Cu(aq) were higher than the concrete and ceramic tile roofs. Mendez et al (2011) found that the asphalt fiberglass shingle roof was expected to be a source of organic matter. Drapper et al (2000) found that TOC and COD concentrations in asphalt road runoff were 3e5 times higher than those from a concrete road.…”

“…Despins et al (2009) found that the quality of harvested rainwater from steel roofs was better than that from asphalt shingle roofs, particularly with respect to total organic carbon, turbidity and color. Mendez et al (2011) examined harvested rainwater quality from five roof types (conventional roofing materials: asphalt fiberglass shingle, Galvalume metal, and concrete tile; alternative roofing materials: cool and green) at Austin, Texas. They found that the metal, concrete tiles and cool roofs were suitable for rainwater harvesting application; however, the shingle and green roofs produced very high dissolved organic carbon concentrations, which could lead to high concentrations of disinfection byproducts.…”

Rainwater Harvesting Systems in Australia

“…The removal of pollutants by collecting the first-flush and separating it from the water in the rainwater tank can result in better water quality in the tank. Mendez et al (2011), however, did not find a significant difference in the water quality in rainwater tank with or without a first-flush. A recent study in Western Sydney showed elevated levels of microbes, nutrients and heavy metals in the first-flush, which were significantly higher than the samples of the harvested water (van der Sterren et al, 2009;.…”

Quantifying Rooftop Rainwater Harvest Potential: Case of Mbeya University of Science and Technology in Mbeya Tanzania

“…On the other hand, the quality of harvested rainwater is influenced by the type of roofing materials. It has been noted that metal roofing materials have lower concentrations of fecal indicator bacteria than other roofing materials [6]. During the onset rainfall, the samples of the collected rainfall indicate that pollutants concentration is high in the first liter but decrease substantially in the subsequent samples [7].…”