All 1,694 public shelters may need mould and pest treatment
Monday 31st August 2026 on 16:01 in
Denmark
All 1,694 concrete shelter trenches with public access in Denmark are expected to require treatment for mould and pests such as rats, according to a document obtained by construction newspaper Licitationen from the Agency for Societal Safety, as reported by DR.
“If the concrete shelter trenches are to be repaired or renovated and possibly prepared for use, all concrete shelter trenches will presumably need to be treated for mould and pests,” the document says.
Denmark generally distinguishes between three types of shelters. Public shelters include the concrete shelter trenches described by the agency. They are intended for people caught outside, such as road users or residents of buildings without shelters.
Most shelter spaces are in so-called protected rooms, which are secured rooms in existing buildings such as residential properties. There are also supplementary shelters that do not meet the requirements but still provide some protection.
According to a 2024 overview, the concrete shelter trenches provided 113,018 of the approximately 3.4 million places in Danish shelters.
A nationwide inspection of all concrete shelter trenches began in December 2025. The inspection was intended to give authorities an updated overview of the shelters’ actual condition and capacity.
It found that just under half of the 1,694 trenches could be put into use in an emergency. Kristeligt Dagblad reported earlier in August, based on a parliamentary question, that 831 trenches meet basic requirements and have “the central permanent installations”.
However, even those 831 shelters were judged to require several remedial measures and “actual preparation” before use.
The concrete shelter trenches were built until the 1950s, for example along roads and in parks in larger cities. They were intended to give people who happened to be in the streets during an air raid a place to seek refuge. Many have since been closed.
The next phase of the national inspection will examine protected rooms.