Royal Dutch Shell, Dong Energy and Centrica are examining a possible design flaw that may lead to wind turbines sinking into their foundations on the ocean floor.

Shell first identified the fault at the Egmond aan Zee wind farm off the Dutch coast. Dong and Centrica both said they are investigating their offshore turbines, reports Bloomberg.

Industry group Renewable UK’s head of offshore power Peter Madigan told Bloomberg the fault could have wider implications for the industry.

According to Renewable UK, repairing all offshore UK wind farms could cost approximately £50m ($77m).