Assessing the impact of COVID-19 lockdown on surface water quality in Ireland using advanced Irish water quality index (IEWQI) model

Md Galal Uddin; Mir Talas Mahammad Diganta; Abdul Majed Sajib; Azizur Rahman; Stephen Nash; Tomasz Dabrowski; Reza Ahmadian; Michael Hartnett; Agnieszka I Olbert

doi:10.1016/j.envpol.2023.122456

Assessing the impact of COVID-19 lockdown on surface water quality in Ireland using advanced Irish water quality index (IEWQI) model

Environ Pollut. 2023 Nov 1:336:122456. doi: 10.1016/j.envpol.2023.122456. Epub 2023 Sep 4.

Authors

Md Galal Uddin¹, Mir Talas Mahammad Diganta², Abdul Majed Sajib², Azizur Rahman³, Stephen Nash⁴, Tomasz Dabrowski⁵, Reza Ahmadian⁶, Michael Hartnett⁷, Agnieszka I Olbert²

Affiliations

¹ School of Engineering, University of Galway, Ireland; Ryan Institute, University of Galway, Ireland; MaREI Research Centre, University of Galway, Ireland; Eco-HydroInformatics Research Group (EHIRG), Civil Engineering, University of Galway, Ireland. Electronic address: mdgalal.uddin@universityofgalway.ie.
² School of Engineering, University of Galway, Ireland; Ryan Institute, University of Galway, Ireland; MaREI Research Centre, University of Galway, Ireland; Eco-HydroInformatics Research Group (EHIRG), Civil Engineering, University of Galway, Ireland.
³ School of Computing, Mathematics and Engineering, Charles Sturt University, Wagga Wagga, Australia; The Gulbali Institute of Agriculture, Water and Environment, Charles Sturt University, Wagga Wagga, Australia.
⁴ School of Engineering, University of Galway, Ireland; Ryan Institute, University of Galway, Ireland; MaREI Research Centre, University of Galway, Ireland.
⁵ Marine Institute, Rinville, Ireland.
⁶ School of Engineering, Cardiff University, The Parade, Cardiff, CF24 3AQ, UK.
⁷ School of Engineering, University of Galway, Ireland; Ryan Institute, University of Galway, Ireland.

PMID: 37673321
DOI: 10.1016/j.envpol.2023.122456

Abstract

The COVID-19 pandemic has significantly impacted various aspects of life, including environmental conditions. Surface water quality (WQ) is one area affected by lockdowns imposed to control the virus's spread. Numerous recent studies have revealed the considerable impact of COVID-19 lockdowns on surface WQ. In response, this research aimed to assess the impact of COVID-19 lockdowns on surface water quality in Ireland using an advanced WQ model. To achieve this goal, six years of water quality monitoring data from 2017 to 2022 were collected for nine water quality indicators in Cork Harbour, Ireland, before, during, and after the lockdowns. These indicators include pH, water temperature (TEMP), salinity (SAL), biological oxygen demand (BOD₅), dissolved oxygen (DOX), transparency (TRAN), and three nutrient enrichment indicators-dissolved inorganic nitrogen (DIN), molybdate reactive phosphorus (MRP), and total oxidized nitrogen (TON). The results showed that the lockdown had a significant impact on various WQ indicators, particularly pH, TEMP, TON, and BOD₅. Over the study period, most indicators were within the permissible limit except for MRP, with the exception of during COVID-19. During the pandemic, TON and DIN decreased, while water transparency significantly improved. In contrast, after COVID-19, WQ at 7% of monitoring sites significantly deteriorated. Overall, WQ in Cork Harbour was categorized as "good," "fair," and "marginal" classes over the study period. Compared to temporal variation, WQ improved at 17% of monitoring sites during the lockdown period in Cork Harbour. However, no significant trend in WQ was observed. Furthermore, the study analyzed the advanced model's performance in assessing the impact of COVID-19 on WQ. The results indicate that the advanced WQ model could be an effective tool for monitoring and evaluating lockdowns' impact on surface water quality. The model can provide valuable information for decision-making and planning to protect aquatic ecosystems.

Keywords: COVID-19 impact; Coastal waters; Cork harbour; Irish water quality index model; Pollutant trend analysis.