Wetenschap - 14 september 2017

A Delta Plan for Bangladesh

tekst:
Albert Sikkema

Bangladesh suffers from flooding every year, but this year’s floods have been exceptionally extensive. High time for a Dutch-style Delta Plan. Work has been going into this for years, and WUR is on board. But there is more to this Delta Plan than dykes, says researcher Catharien Terwisscha van Scheltinga. A central component of it is Bangladesh’s land use planning.

© Sk Hasan Ali / Shutterstock

How many deaths have been caused by the recent flooding in South Asia is not yet known. Estimates range from 1200 to 1600 victims. But this was not a major item of world news; more media attention went to the flooding in the American city of Houston, which caused a handful of deaths. One of the main reasons for this, says Catharien Terwisscha van Scheltinga, is that there are floods and drownings every year in Bangladesh. She lived there for five years to implement education and research projects in the fields of climate change, water management and food security for Wageningen University & Research. She is also one of the architects of a Delta Plan for Bangladesh.

‘The residents of the Bangladeshi capital Dhaka don’t realize there is a huge flooding disaster in their country,’ says Terwisscha van Scheltinga. ‘They don’t suffer much from it. A dyke was built around Dhaka in the 1970s, so the river water no longer flows into the city. Dhaka does still get regular flooding, but that is because of the poor drainage. The present flooding disaster affects the poor in the countryside most. Small farmers who don’t have any food because their land is flooded. And to make matters worse, they are suffering from a failed harvest. Wage labourers are stuck in their villages, so they have no work, no income and therefore no food.’

Bangladesh is as flat as the Netherlands and is carved up by three very large rivers – the Ganges, Brahmaputra and Meghna – which bring huge volumes of water down from the Himalaya every year. At this time of year the annual monsoon rains are added to that. This year the monsoon started early and went on for a very long time, so by the end of August half of Bangladesh was inundated.

Water management
Ten years ago, Prime Minister Balkenende proposed to his Bangladeshi colleagues that thought be given to a Delta Plan for Bangladesh. A few years later, Terwisscha van Scheltinga was involved in a preliminary study by WUR, in which the fundamental question was posed: does Bangladesh need a Delta Plan? ‘We talked to people and came across a lot of dissatisfaction. There were already plans, but they had got stuck at the planning stage, were not integrated with plans in other sectors, and depended largely on the ambitions and ideas of those in power. There was no long-term vision, and you need that if you want to improve the water management for the decades to come.’

And yet Terwisscha van Scheltinga also saw that the time was ripe for a Delta Plan. ‘Bangladesh has been through a long period of economic growth and is on the way to becoming a middle income country. There are still a lot of poor people who live from hand to mouth, but many Bangladeshis are gradually getting into a position where they have the latitude and the money to make long-term plans.’

The preliminary study led in 2014 to the assignment from the Bangladeshi government to draw up a Delta Plan – with Dutch funding. This plan is now under construction by a consortium led by Twynstra Gudde consultants and with other parties including Euroconsult, Deltares, WUR and leading Bangladeshi institutes. The draft is ready. ‘What we are talking about now is the broad lines of a plan. If it is approved, the Bangladeshi government wants to launch an investment programme, with support from the World Bank. That is why the World Bank is already involved in the planning now, so as to avoid delays at a later stage.’

Replacing rice
Central to the Delta Plan is land use planning as part of adaptive water management. ‘We take an integral view of both food and water supplies, which vary from region to region. Part of Bangladesh is very dry, and there the water table is sinking. In that area you want to retain more water and adapt agriculture to the dry conditions, by replacing rice with crops that need less water, for instance. And irrigating more with surface water. This leads to a particular kind of land use which in turn determines what kind of water management you need, where dykes should be built, and how high they should be.’

The issues in the south of Bangladesh, on the Indian Ocean, are completely different. ‘In that area there is a lot of fish farming, especially shrimp farming, which makes use of salt water that comes in with the tide. But there are also rice farmers here who use fresh water and for whom the tide is a problem.’ Here too, you’ve got to come to agreements about land use planning before you can start talking about dykes, explains the researcher. Another element in the Delta Plan is the Ganges Barrage, a large dam with a reservoir intended to capture the monsoon water in the west of Bangladesh. This water can be used in the dry season. The construction of the dam has been postponed for the time being for lack of agreement on a suitable location. Terwisscha van Scheltinga has her doubts about the dam. ‘A dam is structural so you should only construct dams if they offer advantages in all circumstances. If not, you’d better opt for another form of adaptive delta management. That gives you the flexibility to respond to changing circumstances.’

Summer dykes
In this regard, there is another Dutch invention that could be useful in Bangladesh: winter and summer dykes, with water meadows between them. ‘In Bangladesh they are not familiar with the idea of high and low dykes, with farming being allowed in the water meadows but no houses. That could fit well into the Bangladesh situation, but again, this hasn’t been worked out yet.  Neither dykes nor anything else are a silver bullet which solves everything. Our main task is to get a combination of measures which improve both agriculture and water management, and to anticipate the expected climate change.’

As to climate change, Terwisscha van Scheltinga isn’t giving anything away at this point. ‘We must collect facts and data, above all. On the basis of baseline studies I can safely say there is climate change is going on. And then I don’t just mean that the weather in Bangladesh has become more extreme, because climate conditions in this country always varied widely. From our analyses it appears that the rainy season is shifting, so the rains no longer coincide with the farmers’ sowing calendar. In that way, climate change has a direct impact on the food supply.’

Reacties 4

  • Wim

    Veel kleinere stuwmeren kunnen naast water beheersing ingezet worden om voldoende witte energie op te wekken om waterstof aan te maken. waardoor waterstof een exportproduct kan worden.

    Energiemaatschappijen kunnen dan de (deel)investeerders worden.

  • big niggaa

    noice

  • gijs

    help me

  • gijs

    help me


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