Author/Editor		Istenič, Darja; Arias, Carlos A; Vollersten, Jes; Nielsen, Asbjorn H
Title		Improved urban stormwater treatment and pollutant removal pathways in amended wet detention ponds
Type		članek
Source		Journal of environmental science and health, Part A Toxic/hazardous substances & environmental engineering
Vol. and No.		Letnik 47
Publication year		2012
Volume		str. 1466-77
Language		eng
Abstract		Dissolved and colloidal bound pollutants are generally poorly removed from stormwater in wet detention ponds. These fractions are, however, the most bio-available, and therefore three wet detention ponds were amended with planted sand filters, sorption filters and addition of precipitation chemicals to enhance the removal of dissolved pollutants and pollutants associated with fine particles and colloids. The three systems treated runoff from industrial, residential and combined (residential and highway) catchments and had permanent volumes of 1,990, 6,900 and 2,680 m3, respectively. The treatment performance of the ponds for elimination of total suspended solids (TSS), total nitrogen (Tot-N), total phosphorous (Tot-P), PO4-P, Pb, Zn, Cd,Ni, Cr, Cu, Hg were within the range typically reported for wet detention ponds, but the concentrations of most of the pollutants were efficiently reduced by the planted sand filters at the outlets. The sorption filters contributed to further decrease the concentration of PO4-P from 0.04 ± 0.05 to 0.01 ± 0.01 mg L-1 and were also efficient in removing heavy metals. Dosing of iron sulphate to enrich the bottom sediment with iron and dosing of aluminium salts to the inlet water resulted in less growth of phytoplankton, but treatment performance was not significantly affected. Heavy metals (Pb, Zn, Cd, Ni, Cr and Cu) accumulated in the sediment of the ponds. The concentrations of Zn, Ni, Cu and Pb in the roots of the wetland plants were generally correlated to the concentrations in the sediments. Among 13 plant species investigated, Rumex hydrolapathum accumulated the highest concentrations of heavy metals in the roots (Concentration Factor (CF) of 4.5 and 5.9 for Zn and Ni, respectively) and Iris pseudacorus the lowest (CF < 1). The translocation of heavy metals from roots to the aboveground tissues of plants was low. (Abstract truncated at 2000 characters)
Descriptors		RAIN WATER POLLUTANTS WATER PURIFICATION PLANTS FILTRATION METALS, HEAVY NITROGEN PHOSPHORUS GEOLOGIC SEDIMENTS IRON COMPOUNDS ALUMINUM COMPOUNDS