A novel screening tool for the health risk in recreational waters near estuary: The Carrying Capacity indicator

Sci Total Environ. 2019 Dec 1:694:133584. doi: 10.1016/j.scitotenv.2019.133584. Epub 2019 Jul 30.


The present study aims to provide a conceptual framework to help practitioners to improve the quality of recreational waters near estuary, which may be affected by untreated wastewater from Combined Sewer Overflows (CSOs). When CSOs are activated, the concentration of bacteria (e.g., Enterococci and E. coli) in estuary increases, thereby resulting in a potential health threat to swimmers. Here, the bacterial exposure is evaluated using physically-based stochastic model for contaminant transport, while human health risk is determined by Quantitative Microbial Risk Assessment (QMRA). Based on human health risk framework, we quantify the Carrying Capacity (CC) of the recreational water body. Such an indicator is defined as the number of swimming individuals that can be sustained in a beach resort with an acceptable risk threshold. The CC increases by dilution processes and by reduction of the source concentration, which in turn depends on the improvements in the sewage system. The presented approach can be a useful screening tool for policy-makers and other stakeholders, thereby providing a potential solution to the trade-off between economic development and the sustainable ecosystem in coastal areas.

Keywords: Bathing water quality; CSOs impact; Carrying Capacity; Quantitative microbial risk assessment; Recreational waters management; Spatially integrated statistics.

MeSH terms

  • Bathing Beaches
  • Ecosystem*
  • Environmental Monitoring*
  • Escherichia coli
  • Estuaries*
  • Humans
  • Models, Theoretical
  • Risk Assessment
  • Sewage / microbiology
  • Water Microbiology*


  • Sewage