Sluis Eefde has been expanded with a second chamber. This allows more ships to pass through the lock, the waiting times are reduced and the lock is no longer vulnerable due to obstructions. Because the lock with the two characteristic lifting towers from 1933 has national monument status, the new chamber had to be carefully fitted in. On behalf of Rijkswaterstaat, our office has drawn up the ambition document and the aesthetic program of requirements for the expansion. The accompanying frames offered space for the functional expansion and technical modernization of the lock and at the same time safeguarded the qualities of the monumental lock complex. The frameworks for the landscape around the lock have been drawn up in collaboration with MTD Landscape Architects. On 1 July, 88 years after the opening of the original lock, the renovated lock complex was officially inaugurated.

With a throughput of more than 70,000 containers per year, the lock complex at Eefde is an important logistical link between Twente and the port of Rotterdam and the European waterways. At the insistence of Twente industrialists, the 'Twenthe Canals' were dug in the 1930s to be able to transport coal by ship to the textile and machine factories. The lock in Eefde was opened on July 22, 1933. The complex then consisted of a sluice chamber with lifting towers, a pumping station and a drainwork, which is now called the Oude Gemaal. Later, the lock keeper's house, the diesel pumping station and the new drain work were constructed. Lock Eefde was the first of three locks that had to absorb the difference in height between the IJssel and Enschede and Almelo. Architect Dirk Roosenburg was responsible for the aesthetic design of the lock complexes and all bridges over the canal.

As with the design for the original lock complex, functionality was the guiding principle in drawing up the aesthetic program of requirements: improving and accelerating the locking process. Within this, the frameworks have been set up in such a way that the new chamber and all associated technology would be designed and constructed largely below ground level so as not to compete spatially with the monumental lifting towers of the existing lock. Due to the construction of the new chamber, the flood defense system had to move northwards over a great length below and above the lock. The green buffer between the lock and the village of Eefde, formed by mature rows of trees and groves, had to make way for this. Our office formulated the ambition for the restoration of valuable landscape elements and new additions. The frameworks for this were subsequently drawn up together with MTD. Eefde lock is not only important for shipping. The dynamics of the lockout attract a lot of attention. Eefdenaren are proud of 'their' lock and holidaymakers also like to come there. In addition to the functional integration of the new chamber, a great deal of attention was therefore paid to the space on and around the chambers when drawing up the spatial schedule of requirements. Several viewing platforms have been provided for both the old and the new chambers, and the frames on the north side provide a wide boulevard with an overview of both chambers.

Contractor L2T, an occasional collaboration between Mobilis and Croonwolter&Dros, was selected on the basis of a dialogue-driven tender procedure. Our office was involved in this selection on behalf of Rijkswaterstaat and subsequently monitored the aesthetic quality during the design phases as a member of the quality team, together with Rijkswaterstaat, the municipality of Lochem and MTD. Sjoekie de Bijll Nachenius is involved in the process on behalf of BiermanHenket as a spatial quality consultant for Rijkswaterstaat. “The civil engineering architecture of Sluis Eefde has great monumental beauty. By staying close to this purely functional approach when drawing up the frameworks, a harmonious ensemble could be designed in which both the imposing lifting towers from 1933 and the innovative new lock chamber come into their own,” explains Sjoekie de Bijll Nachenius. “In addition, the renovated lock complex has also become intelligent, energy-efficient and sustainable.”