Dry Feet at Last in the Indonesian Banger Polder

Can you imagine 20 centimetres of sea water in your street every day

Local resident

The 80,000 inhabitants of a neighbourhood round the Banger canal in Semarang on the island of Java in Indonesia think nothing of it.

The people who live in this five-square kilometre area are used to the fact that water from the Java Sea flows through their streets every day. And if it rains in Semarang – known as ‘the city of floods’ – the water even finds its way into homes and businesses.

Elevating the buildings only helps temporarily because soil subsidence is between five and 10 centimetres a year. This is caused by urbanisation and the fact that ground water is extracted for domestic water supplies. Meanwhile many businesses have left the area for safer premises elsewhere in the city which means local unemployment is high. The flooding is ruining people’s health and unless measures are taken, the water will continue to rise, and people could even die.

Map of Banger canal

Locals sceptical of plans to create a polder around the choked Banger drainage canal

Local resident

A technical plan was quickly set up under a joint development project by the Indonesian and Dutch governments.

This involves installing a water pumping station and storing water in fish ponds. The locals were not particularly interested. This was the umpteenth plan and one which they themselves would have to pay towards in the form of a polder tax! After all, creating a polder is a long-term project and service and maintenance costs must be paid for. The local council will finance part of the costs, but residents too will have to contribute. They are not impressed by the fact that a polder tax is much cheaper in the long term than continually raising your house. Seeing is believing.

Proposal: a democratic regional water authority based on the Dutch model to build support

Local resident

To embed the polder concept into the community, a polder board was set up to give residents, businesses and scientists a say in the system. But it took time to establish what is a completely new concept in the region. A lot of time. In fact, real support only came when a liaison officer with Indonesian roots became involved. With an eye for local values and customs, he brought the builders and the decision-makers together. Gradually the mood in the neighbourhood changed and several ambassadors for the plan emerged spontaneously during open discussions at information evenings. They became members of the polder board and started a conversation with residents. But there was one condition: they would only pay for maintenance of the polder once it had been implemented and there was proof that it worked.
The efforts of Semarang’s mayor turned out to be vital for the project. By introducing new legislation, he made sure the polder board was given authority and accelerated the construction process when weak project management threatened to lead to delays. The polder board was given a course in water management by experts and developed a budgeting model, a disaster management plan, a maintenance system and a strategic vision which properly safeguards expertise.

© Unie van Waterschappen | Dutch Prime Minister Opens Outfall Pumping Station in Semarang, Indonesia

It works: the risk of flooding falls, from daily to once every 10 years

Local resident

The trust of residents grew when the new polder system even prevented flooding during the high spring tides. Since the new system became fully operational in 2018, inhabitants do not need to waste time protecting their property. The neighbourhood is blossoming at a rapid tempo. New businesses are springing up and people are investing in their houses. They have a perspective for the future again. The polder board is also entering a new phase. In Semarang the team has chosen to put the operation and maintenance of the polder into the hands of the local council. And thus, the Dutch water governance model is adjusted to local circumstances. The polder board remains responsible for the system and has signed a Service Level Agreement with the council. The team is working with enthusiasm to expand the involvement of the community. Its newest campaign: preventing garbage being dumped in the water. This is done through practical solutions such as public litter bins. But even more importantly is the appeal for a sense of responsibility for the collective struggle for dry feet in the Banger polder.