Chemical Characteristics of Urban Stormwater Sediments and Implications for Environmental Management, Maricopa County, Arizona

Abstract

/ Investigations of the chemical characteristics of urban stormwater sediments in the rapidly growing Phoenix metropolitan area of Maricopa County, Arizona, showed that the inorganic component of these sediments generally reflects geologic background values. Some concentrations of metals were above background values, especially cadmium, copper, lead, and zinc, indicating an anthropogenic contribution of these elements to the sediment chemistry. Concentrations, however, were not at levels that would require soil remediation according to guidelines of the U.S. Environmental Protection Agency. Arsenic concentrations generally were above recommended values for remediation at a few sites, but these concentrations seem to reflect geologic rather than anthropogenic factors. Several organochlorine compounds no longer in use were ubiquitous in the Phoenix area, although concentrations generally were low. Chlordane, DDT and its decay products DDE and DDD, dieldrin, toxaphene, and PCBs were found at almost all sites sampled, although some of the pesticides in which these compounds are found have been banned for almost 30 years. A few sites showed exceptionally high concentrations of organochlorine compounds.On the basis of published guidelines, urban stormwater sediments do not appear to constitute a major regional environmental problem with respect to the chemical characteristics investigated here. At individual sites, high concentrations of organic compounds-chlordane, dieldrin, PCBs, and toxaphene-may require some attention. The possible environmental hazard presented by low-level organochlorine contamination is not addressed in this paper; however, high levels of toxicity in urban sediments are difficult to explain. Sediment toxicity varied significantly with time, which indicates that these tests should be evaluated carefully before they are used for management decisions.

Understanding the role of land use in urban stormwater quality management

“…Though numerous research studies have attempted to relate land use to pollutant loadings, the outcomes reported can be conflicting (Hall and Anderson, 1986;Lopes et al, 1995;Parker et al, 2000;Sartor and Boyd, 1972). This is due to the reliance on physical processes and the neglect of important chemical processes in describing various stormwater associated phenomena.…”

“…However the outcomes to-date has been far from conclusive, thus making it difficult to identify cause-effect relationships (Hall and Anderson, 1986;Lopes et al, 1995;Parker et al, 2000;Sartor and Boyd, 1972). The major failure has been the inability to derive statistically significant relationships even though qualitative relationships are generally evident.…”

Polycyclic aromatic hydrocarbon contamination in stormwater detention pond sediments in coastal South Carolina

“…For example, pond sediments collected from several areas within a commercial stormwater pond in Ontario, Canada ( PAH levels = 16,370 ng/g) were toxic to both nematodes and bacteria (Marsalek et al 2002). In addition, pond sediments from a variety of residential, industrial, and commercial stormwater ponds in Phoenix, AZ exhibited acute toxicity to the amphipod H. azteca (Parker et al 2000). This toxicity was primarily attributed to organochloride pesticides (DDT, DDE, chlordane, dieldrin, and toxaphene) and metals (As, Cd, Cu, Pb, and Zn); however, PAH levels in these sediments were not investigated.…”

Ground Water and Surface Water as One Resource: Connectivity and Interaction

“…The impact of human activities on surface stream habitant has been extensively studied throughout the world [1][2][3] [4], and this scientific information is now the basis for many stream restoration efforts [5][6].…”