Sustainable Approaches for Stormwater Quality Improvements with Experimental Geothermal Paving Systems

Abstract

This research assesses the next generation of permeable pavement systems (PPS) incorporating ground source heat pumps (geothermal paving systems). Twelve experimental pilot-scaled pavement systems were assessed for its stormwater treatability in Edinburgh, UK. The relatively high variability of temperatures during the heating and cooling cycle of a ground source heat pump system embedded into the pavement structure did not allow the ecological risk of pathogenic microbial expansion and survival. Carbon dioxide monitoring indicated relatively high microbial activity on a geotextile layer and within the pavement structure. Anaerobic degradation processes were concentrated around the geotextile zone, where carbon dioxide concentrations reached up to 2000 ppm. The overall water treatment potential was high with up to 99% biochemical oxygen demand removal. The pervious pavement systems reduced the ecological risk of stormwater discharges and provided a low risk of pathogen growth.

Renewable energy combined with sustainable drainage: Ground source heat and pervious paving

“…The main focus for laboratory-based experiments of the combined system were concerns regarding the impact on water quality of harvesting heat in the sub-base of a PPS [13].…”

“…Neither GSH nor SuDS are new approaches taken separately, however designing them together, making use of a renewable source of energy as well as finding a secondary use for excess surface water which would otherwise be directed to the storm sewer, is relatively new, and a timely development. In fact, Tota-Maharaj and Paul [13] call this infrastructure the "next generation" of PPS. Laboratory experiments with model test rigs have indicated the potential for this technology, but there has been very little information published at the building scale.…”

Filtering Capability of Porous Asphalt Pavements

“…Porous asphalt pavements are more sustainable alternatives to traditional impervious asphalt and concrete pavements. Interconnected void spaces in the pavement allow for water to infiltrate into a subsurface storage zone during rainfall events [10,11].…”

Decision-Making and Sustainable Drainage: Design and Scale

“…Water can be released gradually or utilised for non-potable purposes. All the devices in Table 1 can play a pivotal role in tackling the impacts of climate change, whether via Ecosystem Services provision through GI [12], or the flooding reduction benefits of devices such as porous paving [7,13]. However, underlying these factors are site-specific features of the drainage catchment which impact on the potential to infiltrate on site, detain water and also to be able to convey it to the next SuDS device, the receiving watercourse or groundwater reservoir.…”