Assessing the water quality response to an alternative sewage disposal strategy at bathing sites on the east coast of Ireland

Abstract

A three-dimensional model is used to assess the bathing water quality of two beaches following changes to the sewage management system. The model, firstly was first calibrated to hydrodynamic and water quality data from the period prior to upgrade of sewage treatment works (STWs), was .tThen it was used to simulate Escherichia coli distributions for discharge scenarios of the periods prior to and following the upgrade of the STWs under dry and wet weather conditions. Escherichia coli distributions under dry weather conditions demonstrate that the upgrade in the treatment worksSTWs has remarkably improved the bathing water qualityquality to a Blue Flag status.Consequently, the Blue Flag status at the two beaches would be regained.The new discharge strategy is expected to drastically reduce the rainfall-related incidents in which environmental limits of the Bathing Water Directive are breached. However, significant exceedances to these limits may still occur under wet weather conditions at Bray beach due to storm overflows that may still be discharged through the two Bray outfalls.

Hydro-epidemiological modelling of bacterial transport and decay in nearshore coastal waters

“…The 2D mesh contained 142,533 nodes and 281,440 elements, the 3D mesh contained 133,341 nodes and 264,237 elements, repeated over 5 sigma layers giving 666,705 nodes and 1,059,648 elements in total. As for similar studies the Smagorinski turbulence closure model was used in the horizontal (Bedri et al, 2015, Abu Bakar et al, 2017b, Guo et al, 2020 and vertical directions.…”

“…To enable accurate and fast dissemination of information it is therefore in the interest of the governing authority to develop predictive tools to provide water quality forecasts and warning systems (Bedri et al, 2014(Bedri et al, , 2016Chen and Liu, 2017;DHI, 2017a, b;Weiskerger and Phanikumar, 2020). Not only would this comply with the rBWD but it could enable the identification, reduction and removal of major pollution sources, increasing the likelihood of a bathing water being assigned Blue Flag status (Bedri et al, 2015;Lea, 1996).…”

Study on layout optimization of sewage outfalls: a case study of wastewater treatment plants in Xiamen

“…The ocean is the ultimate destination of terrigenous pollutants 1 . Discharging the domestic sewage and industrial wastewater meeting the discharge standards into the ocean after centralized treatment is an economical strategy to utilize the marine environment and relieve the offshore environmental pressure 2 , 3 , which is also one of the main ways of sewage discharge in the coastal areas 4 . The ocean can treat some pollutants through self-purification capacity.…”