WIKA Accelerates Construction of Semarang-Demak Toll Road Section 1B
PT Wijaya Karya (Persero) Tbk (WIKA) is accelerating the construction of the Semarang-Demak Toll Road Section 1B as part of efforts to strengthen connectivity in the Pantura (North Coast) region of Java while supporting the integration of the Trans-Java Toll Road network. As of June 2026, the project’s progress has reached 81.19% and is targeted for completion in April 2027.
WIKA’s scope of work on the Semarang-Demak Toll Road Section 1B includes ramp on, ramp off, main road, sea dike, combi wall, and revetment construction. Several major works have already been completed, including the ramp on, ramp off, main bridge, and combi wall. Meanwhile, ongoing work involves the placement of selected material top layer used as preloading for the sea dike.
The Semarang-Demak Toll Road plays a strategic role in reducing traffic loads on the Pantura route, particularly on the Semarang-Demak section, and in strengthening connectivity within the Trans-Java Toll Road system. Beyond supporting public mobility and logistics distribution, the project is also designed with a dual function as a sea dike.
This dual function is one of the project’s key values. In addition to serving as transport infrastructure, the Semarang-Demak Toll Road Section 1B is part of a strategy to mitigate tidal flooding in the coastal areas of Semarang and its surroundings. The project is designed to help address tidal inundation, the impacts of land subsidence, and damage to the Pantura road caused by flooding.
WIKA Corporate Secretary Ngatemin stated that the construction of the Semarang-Demak Toll Road Section 1B reflects WIKA’s contribution to delivering infrastructure that is not only oriented towards connectivity but also provides direct benefits to coastal communities. “The Semarang-Demak Toll Road Section 1B is a strategic project with dual benefits, serving both as a main connectivity route on the Pantura and as tidal flood control infrastructure. Through this project, WIKA is committed to supporting infrastructure development that meets mobility needs while providing protection for the coastal areas of Semarang,” he said, quoted from a written statement on Tuesday (23/6/2026).
In its execution, the project faces fairly complex construction challenges because it is being built on soft soil and is directly connected to the sea area. To address these challenges, WIKA is applying a special construction method involving the use of bamboo piles and bamboo mattresses before the placement of fill material on top. The bamboo pile and mattress structure serves to maintain the stability of the embankment on soft soil while distributing the embankment load evenly.
Additionally, the project employs Prefabricated Vertical Drain (PVD) technology in the soil improvement process. The embankment work is carried out in stages, observing waiting periods at each stage: 55 days for stages 1 through 5, and 150 days for stage 6. These stages are necessary to ensure the embankment density meets the established design requirements.
From the tidal flood control perspective, the project is built with a sea dike elevation above the highest sea water level and is equipped with a revetment structure on the seaward side. The sea dike also synergises with a retention pond that functions to help control water levels on the landward side. Thus, when sea water levels rise, the land area on the Semarang coast is expected to be protected from tidal inundation.
The construction of the Semarang-Demak Toll Road Section 1B has also had a positive impact on employment. At the peak of the bamboo mattress work, the number of workers involved reached approximately 750 people, with around 200 of them being local residents. The involvement of local labour is particularly needed in the manual assembly of bamboo mattresses using nylon rope ties.
Once fully operational, the Semarang-Demak Toll Road Section 1B is expected to provide long-term benefits for the community, especially in alleviating traffic congestion on the Semarang-Terboyo-Demak Pantura route. Furthermore, the sea dike within the project is also expected to help address tidal flooding problems in the coastal areas of Semarang, so that the benefits of the development can be directly felt by the surrounding community.