Indonesia has approximately 20 million hectars of peatland, primarily in Sumatera, Kalimantan, Sulawesi and Papua islands.  This is the largest tropical peatland area in the world and currently facing serious threats due to inappropriate management. 

Peatland’s ability to store water up to 90% of its volume has an important bearing of the hydrology of related watersheds.

Land use changes and human activities such as illegal logging and forest fires cause various hydrological and water management problems, including flooding, erosion and sedimentation, a fall in the ground water table and leaching.

In order to solve the hydrological problems in peatland areas caused by canals or ditches construction in the past it is necessary to manage the hydrology through the blocking of these canals or ditches. This blocking can be made by construction of dams, bunds, weir and controlled blocking

From the case study carried out at the black water ecosystem in the Puning River, Central Kalimantan, Indonesia, many water problems have been identified.  Such problems, including the construction of ditches (small canals) to transport illegal logs, which drained lots of water out from the peatland area; forest and peatland fires, and erosion and sedimentation, which reduced peatland and rivers’ water holding capacity/retention.  Ground water table in the Puning area fluctuates and has a maximum water table of +3m and a minimum water table of –3m. The discharge of Puning River is 97 m3/sec and this goes into the Barito river.  The maximum monthly average rainfall in this area is 360 mm in November, and the minimum monthly average rainfall is 92 mm is July.

In order to solve the hydrological problems in the Puning area which are caused by the existing ditches/small canals, it is necessary to choose methods and techniques which are appropriate for the area, such as controlled/closing of the canals/ditches using local materials, including wood planks and clay.

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