Decreased waterborne pathogenic bacteria in an urban aquifer related to intense shallow geothermal exploitation

Garcia-Gil, Alejandro and Gasco-Cavero, Samanta and Garrido, Eduardo and Mejias, Miguel and Epting, Jannis and Navarro-Elipe, Mercedes and Alejandre, Carmen and Sevilla-Alcaine, Elena. (2018) Decreased waterborne pathogenic bacteria in an urban aquifer related to intense shallow geothermal exploitation. SCIENCE OF THE TOTAL ENVIRONMENT, 633. pp. 765-775.

Full text not available from this repository.

Official URL: https://edoc.unibas.ch/67397/

Downloads: Statistics Overview


The implications of intensive use of shallow geothermal energy resources in shallow urban aquifers are still not known for waterborne pathogens relevant to human health. Firstly, we hypothesized that waterborne enteric pathogens would be relatively increased in heated groundwater plumes. To prove this, microbiological sampling of 31 piezometers covering the domain of an urban groundwater body affected by microbiological contamination and energetically exploited by 70 groundwater heat pump systems was performed. Mean differences of pathogenic bacteria contents between impacted and non-impacted monitoring points were assessed with a two-tailed independent Student's t-test or Mann-Whitney U and correlation coefficients were also calculated. Surprisingly, the results obtained revealed a significant and generalized decrease in waterborne pathogen contents in thermally impacted piezometers compared to that of nonimpacted piezometers. This decrease is hypothesized to be caused by a heat shock to bacteria within the heat exchangers. The statistically significant negative correlations obtained between waterborne pathogen counts and temperature could be explained by the spatial distribution of the bacteria, finding that bacteria start to recover with increasing distance from the injection point. Also, different behavior groups fitting exponential regression models were found for the bacteria species studied, justified by the different presence and influence of several aquifer parameters and major, minor and trace elements studied, as well as the coexistence with other bacteria species. The results obtained from this work reinforce the concept of shallow geothermal resources as a clean energy source, as they could also provide the basis to control the pathogenic bacteria contents in groundwater bodies. (C) 2018 Elsevier B.V. All rights reserved.
Faculties and Departments:05 Faculty of Science > Departement Umweltwissenschaften > Ehemalige Einheiten Umweltwissenschaften > Applied Geology (Huggenberger)
UniBasel Contributors:Epting, Jannis
Item Type:Article, refereed
Article Subtype:Research Article
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
Last Modified:23 Apr 2020 16:03
Deposited On:23 Apr 2020 16:03

Repository Staff Only: item control page