The Leppa aqueduct is part of the A32 motorway near Akkrum, where the motorway passes under the Boarn river. You can use the aqueduct to sail from Terherne and Akkrum to Grou via the Boarn, for example.
Thanks to the aqueduct, you can sail from Terherne via Akkrum to Grou, for example, without having to use the busy Prinses Margriet Canal. It is located just 2 kilometres south of the larger Mid-Fryslân Aqueduct, which does pass over it. The aqueduct is accessible 24 hours a day to road traffic, slow traffic and shipping.
The aqueduct itself has a closed section of approximately 20 metres. The A32 motorway passes underneath with 2x2 lanes, and on the east side there is a separate underpass for slow traffic heading towards Grou.
The aqueduct was built in 1993. For its construction, the course of the Boarn river was shifted about 300 metres to the north. A special construction method, known as “polder construction”, was used during the construction. This involved placing a plastic film in the ground to act as a barrier for the groundwater. This allows the water level within the polder to be controlled, making the construction of the aqueduct feasible.
