A Cost-Optimization Tool for Stormwater Management Plans Using Green Infrastructure Practices

Green infrastructure (GI) is viewed as a sustainable approach to stormwater management that is being rapidly implemented, outpacing the ability of researchers to compare the effectiveness of alternate design configurations. This paper investigated inflow data collected at four GI inlets. The performance of these four GI inlets, all of which were engineered with the same inlet lengths and shapes, was evaluated through field monitoring. A forensic interpretation of the observed inlet performance was conducted using conclusions regarding the role of inlet clogging and inflow rate as described in the previously published work. The mean inlet efficiency (meanPE), which represents the percentage of tributary area runoff that enters the inlet was 65% for the Nashville inlet, while at Happyland the NW inlet averaged 30%, the SW inlet 25%, and the SE inlet 10%, considering all recorded events during the monitoring periods. The analysis suggests that inlet clogging was the main reason for lower inlet efficiency at the SW and NW inlets, while for the SE inlet, performance was compromised by a reverse cross slope of the street. Spatial variability of rainfall, measurement uncertainty, uncertain tributary catchment area, and inlet depression characteristics are also correlated with inlet PE. The research suggests that placement of monitoring sensors should consider low flow conditions and a strategy to measure them. Additional research on the role of various maintenance protocols in inlet hydraulics is recommended.

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Comprehensive Performance Evaluation of Green Infrastructure Practices for Urban Watersheds Using an Engineering–Environmental–Economic (3E) Model

Sustainability ◽

10.3390/su13094678 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4678

Author(s):

Yi-Jia Xing ◽

Tse-Lun Chen ◽

Meng-Yao Gao ◽

Si-Lu Pei ◽

Wei-Bin Pan ◽

...

Keyword(s):

Performance Evaluation ◽

Environmental Economic ◽

Environmental Impact ◽

Pollution Control ◽

Green Infrastructure ◽

Stormwater Management ◽

Economic Cost ◽

Urban Watersheds ◽

Comprehensive Performance ◽

Detention Basins

Green infrastructure practices could provide innovative solutions for on-site stormwater management and runoff pollution control, which could relieve the stress of nonpoint pollution resulting from heavy rainfall events. In this study, the performance and cost-effectiveness of six green infrastructure practices, namely, green roofs, rain gardens, pervious surfaces, swales, detention basins, and constructed wetlands, were investigated. The comprehensive performance evaluation in terms of the engineering performance, environmental impact, and economic cost was determined in the proposed engineering–environmental–economic (3E) triangle model. The results revealed that these green infrastructure practices were effective for stormwater management in terms of runoff attenuation, peak flow reduction and delay, and pollutant attenuation. It was suggested that for pollution control, detention basins can efficiently reduce the total suspended solids, total nitrogen, total phosphorus, and lead. The implementation of detention basins is highly recommended due to their higher engineering performance and lower environmental impact and economic cost. A case study of a preliminary cost–benefit analysis of green infrastructure practice exemplified by the Pearl River Delta in China was addressed. It suggested that green infrastructure was cost-effective in stormwater management in this area, which would be helpful for sustaining healthy urban watersheds.

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Lightweight aggregates to reduce heavy metal pollution in green infrastructure for urban stormwater management

10.5194/egusphere-egu21-7915 ◽

2021 ◽

Author(s):

Concepcion Pla ◽

Javier Valdes-Abellan ◽

Miguel Angel Pardo ◽

Maria Jose Moya-Llamas ◽

David Benavente

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Green Infrastructure ◽

Metal Pollution ◽

Heavy Metal Pollution ◽

Urban Areas ◽

Stormwater Management ◽

Lightweight Aggregates ◽

Urban Stormwater ◽

Runoff Water

The impervious nature of urban areas is mostly responsible for urban flooding, runoff water pollution and the interception of groundwater recharge. Green infrastructure and sustainable urban drainage systems combine natural and artificial measures to mitigate the abovementioned problems, improving stormwater management and simultaneously increasing the environmental values of urban areas. The actual rate of urban growth in many urban areas requires the enhancement and optimization of stormwater management infrastructures to integrate the territorial development with the natural processes. Regarding the quality of runoff stormwater, heavy metals are critical for their impact on human health and ecological systems, even more if we consider the cumulative effect that they produce on biota. Thus, innovative stormwater management approaches must consider new solutions to deal with heavy metal pollution problems caused by runoff. In this study, we propose the employment of Arlita&#174; and Filtralite&#174;, two kind of lightweight aggregates obtained from expanded clays, to remove heavy metal concentration from runoff stormwater. Laboratory experiments were developed to evaluate the removal rate of different heavy metals existent in runoff stormwater. The lightweight aggregates acted as filter materials in column experiments to quantify their removal capacity. In addition, batch tests were also developed to evaluate the exhaustive capacity of the materials. Results from the study confirmed the efficiency of the selected lightweight aggregates to reduce the heavy metals concentration by up to 90% in urban stormwater runoff.

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