A pioneering research, carried out by IDAEA-CSIC, IRTA, Eurecat and companies like Facsa, Protecmed and Nenuphar, has demonstrated for the first time the seasonal performance of an innovative treatment for groundwater contaminated with nitrates, pesticides, and antibiotics.
A nature-based solution
The two pilot plants, located in Barcelona and Castellón, combine:
- Cultivation of microalgae and bacteria.
- Cork and wood biofilter, which facilitates denitrification.
This system has managed to remove up to 98% of nitrates and over 90% of pesticides and antibiotics, adapting to seasonal variations.
The problem of contaminated groundwater
Groundwater, crucial for human consumption and ecosystems, is facing increasing contamination, especially in areas of high agricultural and livestock activity. The presence of antibiotics in water poses a risk of antimicrobial resistance, considered a public health issue.
Conventional methods such as reverse osmosis or activated carbon are effective but come with high costs and waste generation. In rural areas, decentralized treatments are a more sustainable and economical alternative.
Operation of the new system
The metataxonomic study on microbial diversity, carried out by IRTA, revealed that the degradation of wood pellets activates microbial processes that reduce nitrate to molecular nitrogen, improving the quality of the treated water.
Furthermore, the biomass generated during the process can be used for:
- Organic fertilizers in agriculture.
- Biogas production, ensuring a circular economy approach.
Safety of treated water
To assess the suitability of the water, IRTA conducted tests with rabbits for 21 days on a demonstration farm. The results indicated that:
- There were no adverse effects on the animals’ health.
- The feces did not contain antibiotics or resistance genes.
This sustainable and efficient treatment represents a key advancement in protecting water resources, reducing contaminants, and promoting responsible water use.
