Leading water experts offer nuanced view of election campaign’s "wet issue"
The 2026 election campaign was a battle over the protection of Danish drinking water. DTU’s two leading experts in the field offer here a number of clarifications regarding the key messages that remain.
Professors Hans-Jørgen Albrechtsen (left) and Poul Løgstrup Bjerg from DTU Sustain have been actively following the debate on drinking water protection. They are pleased that the issue is part of the political agenda, but feel that important nuances are missing from the election campaign. Photo: Thomas Steen Sørensen
Thursday 13 August 2026
Sari Vegendal
To the left and centre-leaning parties, the case was clear: If drinking water is to be protected, a national ban on agricultural pesticide spraying must be implemented. “No,” was the response from the right and centre-leaning parties, where the Liberal Party and the Liberal Alliance argued for regulation and voluntary agreements as the way forward.
Emotions ran high during the spring election campaign, with one of the hot topics being protecting Danish drinking water and the introduction of a pesticide ban—a measure that has now been implemented in the new government programme.
DTU’s two leading experts in drinking water protection and groundwater and soil contamination, respectively—Professor Hans-Jørgen Albrechtsen and Professor Poul Løgstrup Bjerg—have been following the debate with great interest.
They view increased focus on water protection and the proposal for a pesticide ban as positive, but they are calling for more nuance and expert insight into the many political statements made during the election campaign.
Below they explain in more details the nuances they believe voters should have been made aware of—and which key messages may have caused confusion.
1: Proposal for national pesticide ban
For Professor Hans-Jørgen Albrechtsen, a researcher in drinking water at DTU Sustain, it makes sense to focus on the key issue: the centre/left-leaning parties’ proposal to introduce a ‘national pesticide ban’, which has now been included in the new government programme.
That’s certainly positive, but he believes the wording of the proposal has caused confusion from the start.
“I think it sounded to many people as if the intention was to ban all pesticide spraying in agriculture, even though that was far from the case,” he says, explaining:
“In reality, the goal was to stop spraying in vulnerable groundwater recharge areas (known as SGOs in Denmark), which is exactly what the new government intends to do now. SGOs are designated areas where rainwater seeps down into the aquifers from which we extract the groundwater that is treated to become drinking water. So they account for only a small portion of total farmland in Denmark.”
His colleague Poul Løgstrup Bjerg, who conducts research on soil contamination and groundwater protection at DTU Sustain, agrees with this assessment. He also points out that the discussion of the proposal itself lacked depth.
“It very quickly turned into a question of whether you were for or against a pesticide ban. If you didn’t say ‘for’ off the bat, you were assumed to be against it,” he says—calling for a debate on other possible measures.
“The parties never fully explored the many alternatives. And there are quite a few—from groundwater protection zones, where total protection against all contaminants is implemented, to various targeted measures to regulate the spread,” he says.
2: Timeframe and impact of pesticide ban
With regard to the current pesticide ban, both experts point out that politicians failed to provide information during the election campaign about how quickly the measure would take effect.
“I think many Danes got the impression that a ban on spraying would ensure clean drinking water right away, but that’s far from the reality,” says Hans-Jørgen Albrechtsen.
First of all, he points out that the work to identify the so-called SGOs in Denmark has only just begun—and only once that work is complete will a pesticide ban take effect. Only on Funen has this been done, while the rest of the country still needs looking at.
Second, the impact of an intervention cannot be measured in the groundwater until many years from now.
“The process by which rainwater seeps through the soil into the aquifers is a lengthy one. This means that the groundwater that is currently being turned into drinking water is more than 30 years old,” explains Poul Løgstrup Bjerg, adding:
“So it will also take 30 years or more for the effects of a ban to make a difference. In addition, a pool of pesticide residues is bound in the soil, from which they slowly leach out—and this can further delay the effect of any intervention.”
During the ‘waiting period’—from the time a pesticide ban is enforced until it takes effect—the contaminated water we pump up will still need to be treated so that clean water comes out of our taps.
“A ban is a really good idea, but we will have to carry on cleaning contaminated groundwater—in particularly vulnerable areas—for the next 30 years or more,” concludes Hans-Jørgen Albrechtsen.
Hans-Jørgen Albrechtsen is a professor of Public Health Engineering at DTU Sustain and one of Denmark’s leading groundwater and drinking water experts. His research includes groundwater contamination, pesticides, bacteria in water supplies, and drinking water treatment. He has headed up several major research projects and received the Grundfos Prize (2012) and Grundvandsprisen (2021) for his contributions to Danish drinking water research. Photo: Thomas Steen Sørensen
3: Focus on spraying as the sole source of contamination
Hans-Jørgen Albrechtsen also notes that the focus was almost exclusively on pesticides from agricultural spraying during the election. Although it is important to protect groundwater from agricultural pesticides, he points out that the pesticides currently found in our groundwater do not come solely from agriculture.
“Take for example the pesticide degradation product BAM. It comes from a weed killer that was previously used by both public and private entities. And then there are pesticides from wood preservatives (DMS) used in cities. Both substances are now illegal to use, but they are still in the soil and pose a threat to the groundwater. That’s why they should also be part of a political discussion about drinking water protection,” he says.
“Especially DMS is significant, as it accounts for a considerable portion of the pesticides found in drinking water wells in urban areas,” adds Poul Løgstrup Bjerg.
Experts see the political proposal to limit agricultural pesticides as a very positive step, but they also point out that it is misleading to single out agricultural pesticides as the sole source of contamination.
“For one thing, there are other sources of contamination and a ban on pesticides is far from a solution to all problems. The problem with nitrates in the groundwater, for example, does not stem from the pesticides sprayed by farmers, but from fertilizers,” says Hans-Jørgen Albrechtsen, adding:
“To solve the nitrate problem, we have to also think about regulating fertilizer use in agriculture.”
4: Other substances overlooked
In addition to this, Poul Løgstrup Bjerg felt that the election campaign debates lacked a clear overview and academic depth.
“Where was the thorough analysis of the overall threat? And where were the clear political visions for the future direction? What we got was a simple discussion of a very technical proposal,” he says.
Poul Løgstrup Bjerg is a professor of environmental geochemistry at DTU and one of Denmark’s leading experts on groundwater contamination and water resources. His research focuses on risk assessment and remediation of contaminated soil and groundwater, including pesticides, PFAS, and other environmental contaminants. He has received several prestigious awards for his research, including Ejnar og Aase Danielsen Fondens Miljøpris (2011), ATV-Fondens hæderspris (2012), and Grundvandsprisen (2017). Photo: Thomas Steen Sørensen
Poul Løgstrup Bjerg points to the so-called ‘forever chemicals’—known collectively as PFAS—as an example of a significant issue that was largely overlooked during the election campaign.
PFAS substances come from sources such as firefighting foam and consumer products like food packaging and rainwear, and—like the pesticides BAM and DMS—they are extremely difficult to break down in the environment. That means that they remain in the soil and pose a threat to the groundwater, even though several of these substances are now illegal.
He therefore makes the following recommendation to the expert commission—tasked by the new government with coming up with suggestions on how to address other forms of groundwater pollution:
“I hope the opportunity to conduct a comprehensive analysis of the situation will be seized and that it will be possible to handle various types of contamination. What we need is a holistic approach to protecting our groundwater. This could set the direction for future policy in areas such as agriculture,” he says.
Safe or not?
Drinking water is safe to drink
If anyone is still unsure whether it is safe to drink tap water, the experts want to make it clear that it is the groundwater that is contaminated, not the drinking water.
Drinking water is treated at water treatment plants to ensure that the levels of harmful substances remain below the established limits. However, as groundwater contamination increases, there is also a growing need for research and development in purification technologies to ensure clean and safe drinking water. However, the final message from the two experts is clear:
“Danes should be concerned about our groundwater—not their drinking water. It’s safe to drink water from the tap.”
