Water Quality Improvement through Bioretention: Lead, Copper, and Zinc Removal

Abstract

Intensive automobile use, weathering of building materials, and atmospheric deposition contribute lead, copper, zinc, and other heavy metals to urban and roadway runoff. Bioretention is a lowimpact-development best management practice that has the potential to improve stormwater quality from developed areas. The practice represents a soil, sand, organic matter, and vegetation-based storage and infiltration facility used in parking lots and on individual lots to treat runoff. Investigations using pilot-plant laboratory bioretention systems and two existing bioretention facilities documented their effectiveness at removing low levels of lead, copper, and zinc from synthetic stormwater runoff. Removal rates of these metals (based on concentration and total mass) were excellent, reaching close to 100% for all metals under most conditions, with effluent copper and lead levels mostly less than 5 g/L and zinc less than 25 g/L. Somewhat less removal was noted for shallow bioretention depths. Runoff pH, duration, intensity, and pollutant concentrations were varied, and all had minimal effect on removal. The two field investigations generally supported the laboratory studies. Overall, excellent removal of dissolved heavy metals can be expected through bioretention infiltration. Although the accumulation of metals is a concern, buildup problems are not anticipated for more than 15 years because of the low metal concentrations expected in runoff. Water Environ. Res., 75, 73 (2003).

Lead and zinc removal with storage period in porous asphalt pavement

“…To ensure accuracy of the investigation, a synthetic stormwater was prepared, based on the methods reported by Davis et al (2003) and Myers et al (2007;2011), using ultrapure water to provide consistent water quality. The target pollutants and concentrations in synthetic stormwater were determined based on a report of road runoff quality in Nanjing, China (Yu et al, 2008); however, for this study the concentration of lead was multiplied by 100 providing a 'worst case scenario' to quantify severe impacts on plants, animals and humans.…”

A Mass Balance Model for Designing Green Roof Systems that Incorporate a Cistern for Re-Use

“…Developing undeveloped land reduces the evapotranspiration and increases the stormwater runoff for that area, thereby changing the hydrologic cycle for the watershed. The practice of using plant-and soil-based techniques for treating and holding stormwater at the source to decrease stormwater runoff and increase evapotranspiration rates is called low-impact development (LID) [9]. It should be noted that LID broadly equates to best management practice (BMP), water sensitive urban design (WSUD) and sustainable urban drainage system (SuDS).…”

Effect of slope and paver characteristics on performance of permeable pavement GI.

“…However, while the concentration of many pollutants did decrease after infiltration through the bioretention cell, the concentration of iron significantly increased, and some pollutants such as NO 2-3 -N remained intact. Apart from water quality aspects, using bioretention cells proved to be effective in mitigating peak runoff generated by small and midsize storm events (Davis, Shokouhian, Sharma, Minami, & Winogradoff, 2003;Hsieh & Davis, 2005;Hunt, Smith, Jadlocki, Hathaway, & Eubanks, 2008). Other studies have also verified that bioretention cells can reduce the volume of stormwater runoff, minimize peak flows, and recharge ground water while increasing evapotranspiration (Wossink & Hunt, 2003).…”