Building with Nature in Indonesia

Demak, Northern Java, Indonesia

Communities in Northern Java are suffering from coastal erosion affecting hundreds of kilometers of coastline. In some areas, more than 3 kilometers of land—including entire villages—have already been engulfed by the sea. Eventually, 30 million people in Indonesia may be affected by coastal erosion. As a solution to this problem, a stable coastline in Northern Java is being built through an innovative Building with Nature approach. This project, which was started in 2015 and is scheduled to conclude in 2020, has initiated the construction of permeable structures that help to establish a healthy sediment balance. Once the near-shore seabed level is sufficient, mangroves will establish naturally and will serve as another natural defense against further erosion. This project won The Vernufteling Award 2016, a prestigious Dutch engineering award for innovative engineering solutions in the Netherlands. On behalf of EcoShape, Wetlands International coordinates the initiative in partnership with the Indonesian Ministry of Marine Affairs and Fisheries, and Indonesian Ministry of Public Works and Human Settlements, the consultancy agency Witteveen + Bos, and others.

Above and article cover: Aerial overview of the project area showing sediment accumulation behind permeable barriers installed to capture sediment.

(Photo by Pro57)

Producing Efficiencies

The main causes of the erosion problems are the removal of mangrove belts for aquaculture development, construction of coastal infrastructure that disturbs sediment build-up from offshore sources, and groundwater extraction, which causes land subsidence and river canalization. The Building with Nature approach is being introduced to address these causes, employing the strategies of integrating mangrove and river restoration, small-scale engineering, and sustainable land use.

Groundwater abstraction is a global cause of soil subsidence in many areas of the world. Therefore, informed decisions can only be made by first mapping water demands, planning water availability, considering water safety, and through dialogue. The Building with Nature Consortium is exploring the potential to shift to surface water and severely reduce groundwater extractions, but it is better to first map all the water demand, which the project partners encourage through multi-stakeholder dialogue.

Using Natural Processes

A model is being developed for sustainable aquaculture that provides space for mangrove restoration and requires less use of chemicals in order to enable vulnerable communities and economic sectors to prosper, to be more self-reliant, and to increase their hazard resilience. Permeable barriers have been built from poles and brushwood to dampen the waves and capture sediment. Once the near shore bed level rises enough, mangrove beds will regenerate naturally, creating a natural defense that will protect the hinterland from further erosion. The objective is to replicate and scale up the Building with Nature approach to other rural and urban areas. Building with Nature is innovative and site specific and it operates in areas where the understanding of systems is limited and where changes are dynamic.

Building permeable dams together with local communities.

(Photo by Nanang Sujana)

Broadening Benefits

The goal is to build a stable, restored mangrove coastline that reduces erosion and enables inclusive economic growth, one that can adapt to sea level rise so that communities in Demak are safe and can prosper. This is being accomplished through an inspiring Building with Nature pilot in which a paradigm shift is triggered towards water infrastructure solutions that align the interest of economic development with care for the environment. The alternative “business as usual” scenario will lead to a fully flooded area with evacuated villages and land loss due to land subsidence and erosion.

Semi-permeable barriers and natural mangrove—Desa Bedono.

(Photo by Pro57)

Promoting Collaboration

The measures for the project will be rooted in community development plans and government master planning for sustainable development. A strategy of learning-by-doing has been adopted and the knowledge gained and the lessons learned are being shared widely to support the sound replication of this approach. This sharing will be accomplished through capacity building, knowledge exchange, and embedding in policies and planning.

Building with Nature in Indonesia is a program advanced by EcoShape, Wetlands International, the Ministry of Marine Affairs and Fisheries, the Ministry of Public Work and Human Settlement, Witteveen+Bos, Deltares, Wageningen University & Research, United Nations Educational, Scientific and Cultural Organisation-Delft Institute for Water Education, Von Lieberman, Blue Forests, Diponegoro University, and local communities.

Farmers in Demak are trained through coastal field schools to develop, test, and implement best practices, such as generating farm inputs locally to reduce cost in an ecologically sound way. With the help of government programs, the trained villagers pass on their insights through new training in other villages.

(Photo by Boskalis)