Characteristics and Fate of Stormwater Runoff Pollutants in Constructed Wetlands

Abstract

Nonpoint source (NPS) pollution continues to degrade the water quality. NPS pollutants signals high concerns against a sustainable environment. Low impact development (LID) is the leading management practice which regulates and treats stormwater runoff especially in highly impervious urban areas. Constructed wetlands are known to have efficient removal capability of NPS pollutants. Likewise, these LID facilities were intended to maintain the predeveloped hydrologic regime through series of mechanisms such as particle settling, filtration, plant uptake, and etc. In this study, the objective was to investigate the characteristics, fate and treatment performance of the two in-campus constructed wetlands (SW1 and SW2) which were installed adjacent to impervious roads and parking lots to treat stormwater runoff. A total of 42 storm events were monitored starting from July 2010 until November 2015. Manual grab sampling was utilized at the inlet and outlet units of each LID facilities. Based on the results, the wetlands were found to be effective in reducing 37% and 41% of the total runoff volume and peak flows, respectively. Aside from this, outflow EMCs were generally lower than the inflow EMCs in most events suggesting that the two wetlands improved the water quality of stormwater runoff. The average removal efficiency of pollutants in facilities were 63~79% in TSS, 38~54% in TN, 54% in TP and 32%~81% in metals. The results of this study recommend the use of constructed wetlands as efficient treatment facility for urban areas for its satisfactory performance in runoff and pollutant reduction.

Investigation of the Factors Affecting the Treatment Performance of a Stormwater Horizontal Subsurface Flow Constructed Wetland Treating Road and Parking Lot Runoff

“…The removal efficiency of a nature-based stormwater treatment facility varies depending on the influent water quality, filter media characteristics, microbiological activities, and the type of vegetation utilized in the system [34,36]. Iris, commonly planted in CWs, is effective in removing nitrogen in water [37,38]. Iris is capable of simultaneously absorbing nitrous oxide and deoxidizing nitrogen in its roots [12].…”

“…biological activities, and the type of vegetation utilized in the system [34,36]. Iris, commonly planted in CWs, is effective in removing nitrogen in water [37,38]. Iris is capable of simultaneously absorbing nitrous oxide and deoxidizing nitrogen in its roots [12].…”

Advances in ecotechnological methods for diffuse nutrient pollution control: wicked issues in agricultural and urban watersheds

“…SWs are built particularly for purifying SR and commonly have less biodiversity than natural wetlands in terms of both plant and animal life. Alihan et al (2017) assessed the impact of SWs on controlling initial SR pollution on campus. They found suspended solid, total N, total P, and trace metal elimination rates of 60%-72%, 40%-50%, and 30%-80%, respectively.…”

Bibliometric Analysis and Comprehensive Review of Stormwater Treatment Wetlands: Global Research Trends and Existing Knowledge Gaps

“…It was found that vegetated microcosm wetlands effectively reduced pollutant concentrations in the stormwater by up to 76% [14]. Alihan et al (2017) recommended the use of CWs for treating urban stormwater runoff. The CWs, which treat runoff from impervious roads and parking lots, effectively reduced the total runoff volume and pollutant concentrations by up to 37% and 81%, respectively [15].…”

“…Alihan et al (2017) recommended the use of CWs for treating urban stormwater runoff. The CWs, which treat runoff from impervious roads and parking lots, effectively reduced the total runoff volume and pollutant concentrations by up to 37% and 81%, respectively [15]. Studies regarding the applicability of CWs in agricultural runoff treatment were also conducted by several authors.…”