Towards controlled seasonal flooding pilots in the Mekong delta

Since the publication of the case study about controlled seasonal flooding in the Mekong delta, only few months have passed. What I heard recently is that debates about controlled seasonal flooding are increasingly being discussed in different fora (thanks Dung!). Last September the Vietnamese government repeated in a national workshop that seasonal flooding would positively contribute to the sustainability of agricultural production in the Mekong, and that they are willing to invest national funds in this.

Related, also the Worldbank, as an external investor, remains interested in the concept. Earlier I wrote that the Worldbank aligns tothe Mekong Delta Plan as a holistic framework to invest in various types of water-related projects. There are now initiatives taking shape to implement controlled seasonal flooding in the form of small pilots in some parts of An Giang province. These pilots are well in line with the recommendations brought forward in the MDP.

In this particular case, it is interesting to see if objectives in the field of agriculture and water safety can be met simultaneously. I noticed that controlled seasonal flooding was primarily discussed from the perspective of sustainable agriculture, but also that the ‘hydraulic bureaucracy’ predominantly supported it because of reasons of water safety. Diverting flood water in the northern parts of the Mekong delta, would primarily be good to lower peak water levels, and thereby safeguard urban areas such as Can Tho, further downstream. These are different, perhaps converging, but in practice maybe diverging interests.

This movie (three parts) about (the absence of) seasonal flooding is still very informative: link.

Practices and debates on de-poldering and embankment removal in the Netherlands

The idea to investigate controlled flooding projects was to a large extent influenced by a publication (2006) by Dik Roth, Jeroen Warner and Madelinde Winnubst, who in a detailed way analysed how plans for river widening, de-poldering and restored flooding became heavily debated among policy makers and local residents in the Dutch riverine area from the 1990s. Although related situations occurred in the more distant past (e.g. embankment breaches due to storms, or the abandonment of polders that were agro-economically not viable to maintain), to purposefully remove or relocate embankments started to be discussed in the late 1980s and 1990s. These first initiatives (Ooijpolder, Rijnstrangen, Beersche overlaat) were heavily criticised, not in the last place because of the top-down nature of how such initiatives were presented to local residents. The effectiveness of such interventions, and the major uncertainties that come along with policy making, resulted in fierce debates among different stakeholders. It resulted in the cancellation of the initiatives.

Building on this in my own (collective) research work, the de-poldering of the Noordwaard polder in this respect showed (2013) several similarities when it comes to debating the needs and effectiveness of controlled flooding. Compared to the earlier initiatives, the de-poldering project was much more oriented towards local residents, in terms of participatory processes and the involvement of farmers in discussions about how to continue with agricultural practices and a new spatial plan for the now flood-exposed area. As we discuss in our published article from 2014, the final decision-making stretch could however still be seen as a rather top-down decision, to make an end to growing tensions between policy makers and local residents. 

I would like to highlight one particular conclusion in the article. The de-poldering of the area increases discharge capacities in the region. This 'fixed' discharge capacity also means that any obstruction to achieving this capacity is unwelcome. This concerns excessive growth of vegetation in the floodplain, but also the deposition of sediments within the de-poldered area. As discussed in a previous blog, in the case of Bangladesh, sediment deposition is concerned an important and integral element of Tidal River Management in the coastal polders in Bangladesh. Flood dynamics and sediment deposition increase land height, something that has been similarly proposed via the 'Wisselpolder concept' (rotational polder flooding). The set hydraulic discharge objective obstructs this 'strategic' and long term view on controlled flooding.

Taking these debates to a higher level, it has to be said that flood prevention remains the dominant approach in dealing with flooding in the Netherlands. At the same time, practices and debates on embankment removal are of continued interest and occasionally spark up. I have been able to map quite a number of initiatives that concern de-poldering or restoring managed flooding in different parts of the country. Quite recently the Young Wadden Academy organized a meeting on the topic, provocatively entitled ‘Ditching Dikes’? They were quickly to acknowledge that ditching dikes altogether is not really feasible – but it is interesting in the sense that it contributes to a broader discussion about how to deal with water and land related dynamics typical to deltas, how to respond to ‘peak dynamics’ (e.g. floods) under the influence of climate changes, and how we can give shape to sustainable delta landscapes. It is very interesting to see how this debate, but also how future flood management policies, will develop towards the future in the Netherlands. 

Tidal River Management: from illegal embankment breaching to formalized concept in long-term delta planning

Several delta oriented research programmes have developed an interest in studying Tidal River Management (TRM). The programmes that have put efforts in analysing the specifics of TRM include the Urbanizing Deltas of theWorld programme, the ESPA programme, and ‘my’ Dynamic Deltas research project. Also within Bangladesh, different institutions such as FAO, UNDP and BWDB are conducting research on the topic.

TRM geographically takes place in the coastal zone of Bangladesh. It concerns the temporary removal of polder embankments, which makes these lands liable to tidal flooding again (and temporarily also inhibits agricultural production). Tidal dynamics redistribute sediments, from the adjacent silted up river system, and deposit them on the polder lands. These rivers regain some of their original profile, and within the polder, land is heightened. After closing the embankment again, it takes another 2-3 years to take the polder lands into cultivation again.

Recently published studies interested in TRM are set up from an environmental science point of view (e.g. calculating sediment dynamics, river discharge and tidal flows) but also from a social sciences perspective (e.g. policy analysis, social learning, sustainable livelihoods). Although the list below is probably not fully complete, it gives you an idea about the various dimension of TRM that have most recently (2017) been published.

Mutahara et al (2017): TRM and social learning for adaptive management; Gain et al (2017): interdisciplinary approach towards TRM implementation; Karim et al (2017): local stakeholder analysis of TRM in beel Kapalia. Earlier studies include Nowreen et al (2014) on rationalizing TRM from an historic perspective, and a discussion on the potential effectiveness of TRM in hydro-morphological terms between Auerbach et al (2015) and Hossain et al (2015). There are other articles under construction.

In our article from 2017, Jeroen Warner, Shah Alam Khan and I discuss how past flood management interventions in Bangladesh have oscillated between adopting ‘closed’ or ‘open’ approaches, and how TRM is positioned as an ‘in-between’ intervention. We also note that TRM started not as concept that was being developed and implemented by hydraulic engineers, but as a local initiative, by the authorities referred to as ‘illegal embankment breaching’. Despite its downsides, the embankment breaching also came with advantages and in order to make it acceptable for policy makers and water managers to take it seriously, it needed to be scientifically studied and be given a concept.

From this perspective it is fascinating to see that TRM is currently being discussed within the context of long-term delta planning. The recently published draft version of the Bangladesh Delta Plan 2100 (link or link) is quite positive about the potential of TRM as an element of coastal management in Bangladesh: “When considered, however, as part of an integral strategy for the coastal zone, it may be of interest considering national stakes. This measure is also considered effective for the longer term.” BDP2100 draft, p.300. Moreover, the plan discusses 7 potential TRM locations, referring to a TRM Master Plan developed by BWDB in 2013.

So, a locally contested illegal embankment breaching has made it to a formalized concept being discussed at the highest policy levels in Bangladesh. I'm sure we'll hear much more about it in the coming years. 

Third paper submitted: Tidal River Management in Bangladesh

Some weeks ago I submitted my third article, written with inputs from Jeroen Warner and Shah Alam Khan, to the Water Policy journal. The manuscript is now in review - fingers crossed! A short summary/preview is presented below.

Flooding polders in the coastal zone of Bangladesh

In line with the first case study about de-poldering of and controlled flooding restoration in the Noordwaard polder in the Netherlands, this article goes into related practices in the southwest delta of Bangladesh. What came to be known conceptually as TRM (Tidal River Management) includes the temporary removal of embankments around polders or beels, which enables tidal dynamics to flow in and out of the area. This means that the polder lands are not available for agricultural production for a number of years. The decision to start a TRM project therefore is not easily taken: thousands of people have to temporarily relocate and find other sources of income during this ‘active’ phase of tidal flooding.

But initiating these embankment cuts has to a large extent been driven by a combination of prolonged and severe water related problems: water logging and insufficient drainage capacity within polders, and silted up rivers hampering discharge from the drainage canals into the open water. By opening up the lands, tidal dynamics simultaneously scour river beds and deposit the sediment on the lands. In this way, polder lands increased in height substantially in some cases. By doing so TRM resembles the historic practices of low ‘eight month embankments’ which prevented flooding until rice harvest, after which these embankments started to overflow and spread out floods during flood season, depositing sediments on the land.

These practice happen against a background of a delta described as a ‘fluid environment’ (Lahiri-Dutt and Samanta, 2013) and an interesting social-ecological delta history (Iqbal 2010). Over the last decades many hydraulic interventions have been proposed and sometimes constructed, in an attempt to improve water management and flood protection in the southwest delta region. What can be learned from our analysis is that over the years approaches have ‘penduled’ in between closed and open water management approaches. TRM may be seen as an ‘in between’ concept, as it builds on existing polder infrastructure, but also advocates for periods of ‘openness’ with tidal flooding entering and leaving floodplains. On a final note, TRM has triggered the interest of NGO's, as well as long term policy planners to consider these practices in water policy plans, as well as researchers trying to understand the hydro-morphological dimensions of the concept.

Background info: embankments in the Netherlands

Besides a random online search for pictures about Dutch embankments, the Rijkswaterstaat Beeldbank offers a search function which yields over 15000 hits on the term ‘dijk’ (embankment/levee).

Source: Beeldbank Rijkswaterstaat

In 2015 a book on the history of Dutch dikes was published, which is a full inventory of embankments constructed all over the Netherlands. It was also issued in English and as an e-book. The video on this website gives a short preview of the book. A short and interesting blog posting chronologically summarizes periods in Dutch river management, while there are many books available that go into this topic. Gerard van de Ven’s ‘Man-made lowlands. History of water management and land reclamation in the Netherlands’ and Alex van Heezik’s ‘Battle over the rivers. Two hundred years of river policy in the Netherlands’ are two well-known examples, which can be found here and here.

The future of Dutch embankments is receiving substantial attention from different angles. The Delta Programme focusses on embankment strengthening and heightening within a climate adaptation context. The Room for the River Programme (nearly completed) also included river widening and embankment removal (or de-poldering). Recently moves were made to consider Dutch embankments as cultural heritage. 

Background info: Oosterschelde storm surge barrier

Besides a random online search for pictures about the Oosterschelde storm surge barrier, a dedicated website provides images as well as basic historical background about the delta works. It offers a subpage in English on the barrier itself, as well as a virtual tour (also available here) over/through the barrier’s interior.

This kind of information mainly functions as promotion material, and does not critically go into the socio-political dimensions of the dam. The decision to construct the dam in the first place, the resistance that rose against those plans, and the alternatives in terms of design are lively described by Paul de Schipper in his book ‘De slag om de Oosterschelde’ (the battle about the Oosterschelde). Unfortunately his account is written in Dutch, but several academic scholars, including Wiebe Bijker and Cornelis Disco have investigated political and scientific particularities of the structure in English. Their articles can be found here and here. 

 Source: Beeldbank Rijkswaterstaat

 Source: Beeldbank Rijkswaterstaat

Chris de Stoop: into de-poldering along the Belgian Scheldt

During the last weeks I read two books (written in Dutch) by Belgian author/journalist Chris de Stoop. 'De bres' (the breach - 2000) and 'Dit is mijn hof' (this is my yard - 2015). I found them quite intriguing – especially because they deal with the perspective of Belgian farmers regarding de-poldering plans and actions along the Belgian side of the Scheldt river. Although what follows below is far from a review (you may want to read this, although it is in Dutch), a short outline of his story is presented below. To start with the my main conclusions, drawn from the books: 1) de-poldering is not typically a Dutch thing, and 2) when it comes to driving forces, it is not only water/nature coalitions, but in this case also the harbour of Antwerp that drives the practice.

Both of de Stoop’s books deal with the region of Doel (or Waasland), located on the western shore of the Scheldt river, and west of Antwerp and its harbour. Due to its fertile clayey soil, this predominantly agricultural land yields some of the highest production in western Europe in terms of livestock production and potatoes measured per acre. In the 1960s and 70s, parts of the region were still wetlands (for example, het Verdronken Land van Saeftinghe, located just across the Dutch-Belgian border) which were planned to be drained, reclaimed and added to the ‘granary of northwest Europe’.

But by the 1980s and 90s, the farmer communities started to be confronted with plans to use this land in a different way: to enable the geographical expansion of the harbour of Antwerp. Plans, politics and actions to de-polder and to turn farm lands into docks and container terminals took hold, resulting in many farmers that were expelled from their lands. This took a heavy toll on individual farmers (de Stoop mentions at least one suicide) as well as the farming society as a whole, who saw many of its members departing or quitting with farming entirely. He describes the politics and games that are played in a very moving way, but also as classic good guys versus bad guys way.

In the 1990s, ideas about ‘nature compensation’ following the harbour expansion, and also allocating space for water from the perspective of water safety, were added to the agenda of de-poldering agricultural lands. The de-poldering of the Hedwige/Prosperpolder (on the Dutch-Belgian border), in which 900ha of agricultural land in both countries is being opened up to tidal dynamics, comes back as a case at several places.

On the upper map (source: http://www.kuleuven.be/pdl/uitstappen/2008doel.html) with Doel as a central dot, you see the area is fully in use for agriculture, with polders and canals adjacent to wetlands (het Verdronken Land van Saeftinghe in the northwest). On the lower map (source: http://www.doel2020.org/index.php) you see Doel as well, but now including existing (in blue) and newly planned docks (in pink)/terminals following the expansion of harbour activities, at the expense of farm land.

In his books, de Stoop is very critical towards nature organizations. In the past, he argues, nature organizations were partners of farmers in their continuous battle against, for example, their expanding neighbour. This changed when nature organizations stopped their alliance with farmers - nowadays, they partner with the harbour of Antwerp itself. He argues that they follow an agenda of searching for agricultural areas that can be (temporary) turned into natural areas as compensation for the harbours’ expansion and dredging work to keep the Scheldt at depth. Cynically, he adds, some of the new docks turn out to be obsolete, and many new nature areas do not develop as desired, requiring additional ecological engineering. Nature organizations, in their turn, argue that working together with the harbour would give better and quicker results, compared to resistance to any plan.

De Stoop’s descriptions are clearly from the perspective of the farmers and in that sense biased and dichotomized. But he does so with a purpose: returning to his homeland after his brother passed away gave him the chance to take up the work in agriculture again as well as explore how the farming community has experienced the plans and actions to expel them, for over 20 years. What is most striking are the political games that are played, as he describes the merciless measures that are taken to get farm land free for other purposes.

I’m now searching for books or viewpoint that tell the other side of the story ;p.