title: Rooftop runoff as a source of contamination: a review.
abstract: Scientific reports concerning chemical and microbiological contaminant levels of rainwater runoff from rooftop collection in both urban and rural areas are reviewed. This alternative source of water has been documented to often contain substantial amounts of contaminants. Studies describing levels of heavy metal contamination specific to runoff from rooftop catchment areas containing exposed metal surfaces are discussed. Depending upon the intended use, scientific evidence is also accumulating that various treatments and disinfections will be required prior to release of roof-runoff water either into surface waters or for more direct consumer usage. For microbial contamination, current proposed standards and guidelines regarding this type of water source are shown to vary widely worldwide. Scientific literature reveals a lack of clarity regarding water quality guidelines and health related standards for certain types of rooftop runoff. Studies suggests that rainwater collection systems which are properly designed, maintained, and treated may provide a valuable supplement to existing water supplies by reducing demand on community water supplies/infrastructure costs, enhancing effective management of storm water runoff, and increasing restoration of underground reservoirs through controlled infiltration.
authors: USEPA, MCEARD, MS 314, 26W. Martin Luther King Drive, Cincinnati, Ohio 45268, USA. lye.dennis@epa.gov
authors: Dennis J
authors: DJ
authors: Lye
mesh_terms: D003247:Conservation of Natural Resources; D004784:Environmental Monitoring; D004787:Environmental Pollution; D011891:Rain; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis; D014881:Water Supply
chemical_list: D014874:Water Pollutants, Chemical