Field monitoring of a LID-BMP treatment train system in China

Abstract

In order to assess the urban runoff control effectiveness of a low-impact development best management practice (LID-BMP) treatment train system, a field test of selected LID-BMPs was conducted in China. The LID-BMPs selected include three grassed swales, a buffer strip, a bioretention cell, two infiltration pits, and a constructed wetland. The test site is in a campus in southern China. The LID-BMPs, connected in a series, received stormwater runoff from four tennis courts with an area of 2808 m(2) and eight basketball courts with an area of 4864 m(2). Construction of the LID-BMPs was completed in early spring of 2012, and the sampling was conducted during May of 2012 to September of 2013. During the sampling effort, besides the performance evaluations of grassed swales and the bioretention cell in controlling runoff quantity as well as quality, the emphasis was also on determining the performance of the LID-BMP treatment train system. A total of 19 storm events were monitored, with nine producing no runoff and ten producing runoff. Data collected from the ten storm events were analyzed for estimating runoff quantity (peak flow rate and total runoff volume) and quality reduction by the LID-BMPs. The sum of loads (SOL) method was used for calculating the water quality performance of LID-BMPs. Results indicated that, for peak flow rate, a bioretention cell reduction of 50-84 % was obtained, and grassed swale reduction was 17-79 %, with a runoff volume reduction of 47-80 and 9-74 %, respectively. For water quality, the bioretention cell in general showed good removal for zinc (nearly 100 %), copper (69 %), NH3-N (ammonia nitrogen) (51 %), and total nitrogen (TN) (49 %); fair removal for chemical oxygen demand (COD) (18 %); and poor removal for total suspended solids (TSS) (-11 %) and total phosphorus (TP) (-21 %). And its performance effectiveness for pollutant removal increased in the second year after 1 year of stabilizing. When considering the aggregated effect of the LID-BMP treatment train system, it showed excellent removal for NH3-N (73 %), TN (74 %), and TP (95 %) and fair removal for COD (19 %) and TSS (35 %). The assessment results of the LID-BMP treatment train system provide valuable information on how to link the different types of LID-BMP facilities and maximize the integrated effectiveness on urban runoff control.

Assessing cost-effectiveness of specific LID practice designs in response to large storm events

“…There have been both field and laboratory experiments examining the hydrological processes in urban areas with LID practices (e.g., Brattebo and Booth, 2003;Liu et al, 2014;Wong and Jim, 2014;Jia et al, 2015a), revealing the effectiveness of LID practices in urban runoff and water pollutant control. There have also been a rising number of numerical modeling studies using stormwater http://dx.doi.org/10.1016/j.jhydrol.2015.12.011 0022-1694/Ó 2015 Elsevier B.V. All rights reserved.…”

Urban Stormwater Characterization, Control, and Treatment

“…These studies are potentially defining their own research niches, and include using treatment trains (Jia, Wang et al, 2015), retrofitting traditional urban stormwater infrastructure with LID (Palanisamy and Chui, 2015), and using mycofiltration for treating stormwater (Taylor et al, 2015). Jia, Wang et al (2015) monitored a LID treatment train that included grass swales, a buffer strip, two infiltration pits, and a constructed wetland. Results were indicative of the individual processes associated with the various practices, and demonstrate the potential of optimizing treatment trains for removal of suites of pollutants.…”

Sustainability

“…The hydrologic performance of rain gardens in Ohio, USA was evaluated using modeling techniques concluding that, for the modelled configurations, infiltration played a primary role in rain garden performance (Jennings et al, 2015). Field test results from the study of a treatment train, consisting of three grassed swales, a buffer strip, bioretention cell, infiltration pits, and a constructed wetland in China are presented by Jia et al (2015), indicating effective combination of treatment technologies for the reduction of peak flows and volume of runoff as well as improvement of water quality including nitrogen, phosphorus, TSS and metals. Two green roofs and a bare, unplanted, roof in Hong Kong were compared finding that the peanut plot had higher evapotranspiration than Sedum (Jim, 2015).…”