Quantifying Thermal Characteristics of Stormwater through Low Impact Development Systems

Abstract

Urbanization causes alteration of the thermal regime (surface, air, and water) of the environment. Heated stormwater runoff flows into lakes, streams, bays, and estuaries, which potentially increases the base temperature of the surface water. The amount of heat transferred, and the degree of thermal pollution is of great importance to the ecological integrity of receiving waters. This research reports on a controlled laboratory scale test to assess low impact development (LID) stormwater control measure impacts on the thermal characteristics of stormwater runoff. We hypothesize that LID stormwater control measures (SCMs) such as pervious surfaces and rain gardens/bioretention can be used to mitigate the ground level thermal loads from stormwater runoff. Laboratory methods in this study captured and infiltrated simulated stormwater runoff from four infrared heated substrate microcosms (pervious concrete, impervious concrete, permeable concrete pavers, and turf grass), and routed the stormwater through rain garden microcosms. A data logging system with thermistors located on, within, and at exits of the microcosms, recorded resulting stormwater temperature flux. Researchers compared steady state temperatures of the laboratory to previously collected field data and achieved between 30% to 60% higher steady state surface temperatures with indoor than outdoor test sites. This research helps establish baseline data to study heat removal effectiveness of pervious materials when used alone or in combination as a treatment train with other stormwater control measures such as rain gardens/bioretention.

Simulation and Comprehensive Evaluation of the Multidimensional Environmental Benefits of Sponge Cities

“…The nonpoint source pollution reduction rate is 45.18%. LeBleu et al [21] The average leachate temperature in permeable paving is approximately 2 degrees Celsius lower than in pavement runoff.…”

“…For example, Glick et al [16], Abduljaleel et al [17], and Quichimbo-Miguitama et al [18] simulated the hydrological benefits in their study areas, among which Quichimbo-Miguitama also focused on the inundation reduction benefits; Seo et al [19] and Deng et al [20] conducted simulations to evaluate the hydrological and nonpoint source benefits in the study area. In regard to ecological improvement benefits, LeBleu et al [21] found that LID stormwater control measures would reduce the heat load of stormwater runoff and mitigate the urban heat island effect to some extent; Shen [22] simulated the heat island effect mitigation effect of green roofs; Lin et al [23] used the life cycle assessment method to quantify the carbon reduction in the study area. In cost-benefit research of grey and green infrastructure, Wilbers et al [24] divided the benefits of grey and green facilities into direct benefits (avoidance of sewage overflows and urban flooding) and co-benefits (aesthetic value, increase in house prices due to green roof installation, prevention of sewage disposal, water use, etc.)…”

Simulation and Comprehensive Evaluation of the Multidimensional Environmental Benefits of Sponge Cities

“…In regard to ecological improvement benefits, LeBleu et al [21] found that LID stormwater control measures would reduce the heat load of stormwater runoff and mitigate the urban heat island effect to some extent. Shen [22] simulated the mitigation of the heat island effect by green roofs.…”

Increasing Sustainability of Residential Areas Using Rain Gardens to Improve Pollutant Capture, Biodiversity and Ecosystem Resilience

“…Stormwater carries pollutants and discharges them to surface waters. Pollutants include: Heavy metals (such as lead, zinc, copper, and cadmium), polycyclic aromatic hydrocarbons, soluble salts, pesticides, nitrogen, solids, pathogens, pharmaceuticals, and P. Phosphorus, a main pollutant in urban areas, enters waterways with surface water runoff degrading the waterways through over production of algae and aquatic plant growth [4][5][6][7][8][9][10][11]. The main source of urban P is residential lawns and streets.…”