The Urdaibai 'laboratory' gathers lessons learned in light of new European water mandates

Bilbao, July 25 (EFE).- The "laboratory" that the beautiful Biscayan area of the Urdaibai Biosphere Reserve has become, where a team has been researching for years to improve the quality of water intended for human consumption, is gathering lessons of potential interest in light of new European requirements to protect water catchments.

The European Drinking Water Directive, transposed into Spanish law by Royal Decree in 2023, requires Member States to assess risks in water catchment areas for human consumption by 2027 to ensure its quality.

This is where the so-called "Urbaso methodology" could be of interest. It is based on establishing protective perimeters around the catchment area. This methodology is promoted by the research team working in the Urdaibai Biosphere Reserve, where 39 water extraction points are located in forested areas, 13 of them in pine and eucalyptus plantations.

Researchers from the EU-funded Life Urbaso project are working under the coordination of the Neiker Research Center to demonstrate that proper forest management, which reduces soil erosion in the watersheds surrounding catchments, improves the quantity and quality of drinking water by ensuring that less sludge and sediment end up in the watershed.

The BC3 climate change research center, the University of the Basque Country (EHU), the Bilbao Bizkaia Water Consortium, and the EFE Agency are also participating in the project.

"Novelty" in the legislation

Professor of Hydrogeology at the University of the Basque Country, Iñaki Antigüedad, explained to EFE that the European directive introduces a novel approach to risk assessment and management in the catchment area.

This means that, instead of the traditional approach that looks at the "pipe" that carries the water to the Drinking Water Treatment Plant (DWTP) as the starting point, it focuses on the catchment area: It's about "turning 180 degrees and saying 'I get the water here, but where does the water come from?'"

A marteloscope simulates sustainable forest management strategies in Urdaibai.

The new regulations advocate a "holistic approach" to risk management in catchment areas, placing them at the heart of measures aimed at reducing the level of purification required for drinking water production.

In this context, the Department of Antiquity has indicated that the "Urbaso methodology" being developed in Urdaibai, with several years of research focused on three "rings" of protected areas in catchments with a different forestry system implemented in each, could be applicable to rural areas of the Cantabrian Sea.

"Aggressive" forestry activity

"In rural areas where the catchments are surface water, the risk to water quality doesn't come from industry. The main problem comes from forestry activity," he stated, which is what Life Urbaso aims to address.

The expert lamented that "today," forest management practices, especially those related to pine and eucalyptus plantations, "are still quite aggressive with respect to water resources."

"Anyone who goes to the mountains will see scrubland, destruction from heavy machinery, and loss of soil..." he noted.

This loss of soil, he said, causes an increase in sediment in streams, and when heavy rains occur, it produces "that chocolate brown color we see when there are significant flows."

He insisted that most of this "chocolate" is generated by "inappropriate soil management in forestry," and this issue "is not given the importance it deserves," he lamented, because "we have the big-city mentality that believes industry is what pollutes."

However, he warned, in this case there is "a water quality problem," since "many times it cannot be collected because such turbid water cannot be transported to a DWTP."

"The high turbidity of the water," he argued, "is at the root of the problem of trihalomethanes," chemical compounds formed by the reagents used in the DWTP to improve water quality at source and which are a cause for concern in Europe due to their potential health risks.

"Urbaso Methodology"

The Antiquity Department has deemed it "unthinkable" that the risk assessment and management of each water catchment area, each with its own unique characteristics, can be carried out in a short period of time.

Given this, and as long as there is no other methodology, the Urbaso project's methodology can be useful as a starting point and basis for carrying out the corresponding work, he stated.

UE Research focuses on Life Urbaso, a project to improve water in Urdaibai.

The professor also praised the Life Urbaso project in the context of climate change and rising temperatures, aiming to achieve not only greater quality but also greater quantities of water for human consumption by controlling the phenomenon known as evapotranspiration.

Linked to climate change, this phenomenon is accelerating because water evaporates faster at higher temperatures.

A future scenario of higher temperatures would make it inadvisable to surround the water catchment with vegetation with high water demands, since in times of drought, "eucalyptus trees—a major water consumer—continue to drink" while the catchment dries up, the expert warned. EFE