Hydrochemical and microbiological evaluation of groundwater in an agricultural area of Ecuador

Abstract

Hydrogeochemical and microbiological parameters of groundwater samples in the Paipayales agricultural community in western Ecuador were studied to evaluate groundwater origin, contamination, and suitability for domestic use and irrigation. The water wells studied are typically shared by multiple families which account for 37% of the total community population. A total of 31 parameters of water samples from the wells used by the community were analysed by four laboratories at the ESPOL University. The parameters analysed included microbiological and chemical compounds, along with physical characteristics typically influencing water quality. As regards the World Health Organization (WHO), U.S. Environmental Protection Agency (EPA), and Ecuadorian standards, all samples failed to meet the required concentrations for at least one compound. The chemical analysis showed eight elements (cadmium, aluminium, ammonia, iron, manganese, chloride, and bromide) exceeded the maximum limits for drinking water in at least one well. Seventy percent of sampled wells failed to meet the maximum permissible limits for at least one chemical parameter. Water in all wells showed the presence of microbiological contaminants. The high natural groundwater salinity limits the ability to use this groundwater for irrigation purposes. Water in open and closed wells shows different hydrochemical and microbiological patterns. The presence of domestic animals and the lack of protection for wells may influence the quality of water. It is highly recommended that the authorities increase water supply and storage capacity to improve the availability of drinkable water in rural communities in the area.

Keywords

• agriculture
• contamination
• groundwater quality
• microbiology
• well