Performance of an Underground Stormwater Detention Chamber and Comparison with Stormwater Management Ponds

Abstract

Abstract:The transportation of pollutants from impervious surfaces during runoff events to receiving water bodies is a serious environmental problem. Summer runoff is also heated by impervious surfaces, causing thermal enrichment in receiving water body systems and degradation of coldwater aquatic ecosystems. End-of-pipe stormwater management facilities that are open to the environment can result in further elevated temperatures due to exposure to solar radiation. Receiving water systems that provide coldwater habitat require cool water temperatures to sustain healthy conditions for cold water flora and fauna (e.g., trout, dace). Underground Stormwater Detention Chambers (USDC) are a technology for the detention and treatment of stormwater runoff that can potentially solve the thermal issues associated with sun-exposed detention facilities while still providing an equivalent level of treatment services for stormwater pollutants. A field study of an USDC located in Southern Ontario was undertaken to characterize its treatment performance and effect on water temperature. The results were: the USDC was found to provide similar levels of stormwater treatment as wet detention ponds. On average, outlet maximum temperatures were 5˝C cooler than inlet maximum temperatures, and outlet water temperatures remained within the thermal regime for coldwater fish habitat throughout the evaluation period. There was little to no stratification of temperature, nor dissolved solids, but stratification of dissolved oxygen was observed mid-winter and into the spring.

Evaluating the water quantity and quality performances of underground gravel filter basins.

“…As shown in Figure 49, the most significant thermal effect is a pronounced reduction in event maximums, where the median values of the outlet maximum temperatures were found to be 1.8 °F lower compared with the temperatures in the entrance manhole. A similar pattern of outflow temperature reduction in underground detention systems was observed in previous studies (Drake et al, 2016;Natarajan and Davis, 2010). This reduction of temperatures in the outflow would prevent thermally enriched runoff during the summer months from discharging into receiving streams.…”

“…Underground detention chambers are also known to reduce suspended solids, thermal effects, and metal concentrations in stormwater runoff (Drake et al, 2016).…”

“…The GISs are used to reduce the peak flow and volume. These structures can also have a considerable impact on reducing the pollution loads and concentrations carried by the stormwater runoff (Bean et al, 2007) and may have an effect on water temperature and reducing stream warming (Drake et al, 2016).…”

Hydrodynamic modelling of the influence of stormwater and combined sewer overflows on receiving water quality: Benzo(a)pyrene and copper risks to recreational water

“…E6, E20, E45 and Lundbyleden with approximately 200 000 AADT (City of Gothenburg 2017), large water quality benefits would be gained. Underground retention or detention facilities have the potential to save valuable urban land while removing particles and bound pollutants as well as reducing peak flows (Drake et al 2016, Tran and Kang 2013, US EPA 2001. Such a sedimentation facility already exists in Gårda in Gothenburg, where to runoff from 2.1 ha of the E6/E20 is drained and treated.…”

Application of Artificial Neural Networks in the Dimensioning of Retention Reservoirs

“…the Blaszczyk model for rainfall [12,17]. The model largely simplifies the rainfall and leads to disturbance in the hydrological processes within the rainfall (sewer system) retention reservoir system [18,19]. A frequent consequence of this is the underestimation of the required retention facility volume, which increases the risk of wastewater overflow from the sewer system, resulting in local flooding.…”