Something did not quite chime about Michael Buckley’s ‘High and dry’ in the February-April Mekong Review, although initially I could not put my finger on it. The empirical evidence and regional examples to back up his contentions of a river system in serious trouble were all sound.

Buckley made no bones about the river’s aquatic ecology: ‘What is transpiring here is ecosystem collapse’. And I would not disagree. But all the same, there was a piece of the jigsaw missing. Virtually all the blame for the sad state of affairs was being placed at the concrete footings of hydropower dams. What was absent was a commensurate discussion about the role of irrigation schemes. After all, can a migrating fish differentiate between a wall of concrete designed to store water for hydropower generation and a wall of concrete designed to store water for irrigation purposes?

According to a database compiled by the CGIAR’s Water, Land and Ecosystems Research Greater Mekong Programme, of 364 large dams logged in the Mekong basin up to 2015, 176 are designed for hydropower, 185 for irrigation and three for ‘other’ purposes. But irrigation dams, oddly, do not seem to attract a fraction of the attention (or outrage). Of the countries in the basin, Thailand has by far the greatest number of irrigation schemes, with 142 located in the north-east region alone. In total across the lower Mekong basin (LMB), in 2015 there were estimated to be just over 5.1 million hectares under irrigation: about 36 per cent of the total agricultural land area, according to the Mekong River Commission’s State of Basin Report in 2018. In Vietnam, the overall area under irrigation is greatest at over 700,000 ha, mostly concentrated in the Mekong Delta. The total ‘command area’ of these projects is many times greater than that of hydropower projects, which mostly comprise a dam structure, a reservoir and a headworks area; therefore the ecological footprint of these projects tends to be spread wider. Most of the area classified as ‘irrigated’ across the LMB is devoted to the cultivation of rice, one of the thirstiest staple food crops on the planet.

Hydropower dams do tend to be higher, grander and more visible than their irrigation counterparts, giving them a more iconic status for would-be nation builders. Such dams inevitably have a massive impact on the aquatic environment when located on mainstream or large tributary rivers. But what else might explain why irrigation tends to be overlooked in the majority of articles invoking ecosystem crashes? One reason might be that most large hydropower schemes since the late 1990s have been public-private partnerships, bringing to the fore the issue of evil capital interests profiting. By contrast, nearly all irrigation schemes have been state-driven affairs, with financing coming either entirely from the domestic budget, or from a mixture of foreign aid loans and grants, backing up domestic funds. Hence, the schemes are considered state property from day one and are placed under state bureaucracies to greater or lesser degrees, usually directly proportional to the scale of the project.

Alternatively, it might be related to a common perception that irrigation schemes are built for the primary benefit of ‘poor farmers’. Hydropower has frequently fostered popular perceptions of being driven by greedy multinational corporations, distant industrial interests and wealthy urban energy consumers; irrigation is seen as a far more benign enterprise. One agricultural economist, reflecting a systemic and optimistic bias in World Bank-financed large irrigation project appraisals, posed the rhetorical question, ‘Irrigation is such a good thing—who can be against it?’ While the self-interest of farmers who might receive heavily subsidised water seemed a fairly obvious motivation, he noted there was also a general lack of accountability and transparency in national bodies that allowed projects to proceed smoothly to implementation, helping to conceal hidden interests including irrigation agency bureaucrats, lending agency staff, development consultants and construction contractors. As a result, over-blown economic assumptions about benefits and production were (and are) the norm. Added to which, there is invariably a wall of official hubris and obfuscation surrounding performance of individual irrigation projects, so accessing reliable information and data can be challenging.

What emerges in such an atmosphere is an omertà-like code of silence concerning repeated and systemic failure: a willingness by those in authority to go to great lengths to conceal what has become an ‘inconvenient truth’. Over years of studying this phenomenon and the motivations of the actors and institutions involved, I have concluded that widespread irrigation failure has been brushed under the carpet. While one might anticipate that officials serving authoritarian states might be coy and unwilling to critically appraise the sector, it has been rather more surprising to encounter varying degrees of obfuscation, silence and censorship within Western nations’ development institutions.

There is significant confusion and poor awareness about the type and extent of negative environmental impacts from irrigation schemes. Buckley’s article correctly draws attention to many factors besides the physical blocking of migration routes upstream and downstream by dams. These include a drop in sediment and nutrient content in the river as it settles out in reservoirs and marked changes in the timing and magnitude of the floodpulse regime, both critical for the life cycle of hundreds of fish species. Water quality parameters change upstream and downstream of hydropower dams, and the same impacts also pertain for irrigation dams.

But irrigation also precipitates environmental impacts not found in hydropower. When water is diverted and channelled through canals, fields and drainage ditches before being released back into the river, it undergoes qualitative and quantitative changes. In the vast majority of irrigation schemes, farmers invariably liberally use pesticides and chemical fertilisers. Pesticides are often used incorrectly in dosage and timing, frequently mixed together in more potent cocktails, while many types routinely applied are banned elsewhere in the world. Farmers, often poorly trained and lacking awareness of the dangers, frequently wash out or dispose of pesticide containers directly into fields, canals and water sources. Hence, the outflow water becomes tainted with the toxic residues and salt, often brought to the surface by irrigation. Salinisation is a huge problem in northeast Thailand.

I have long been trying to locate exceptions to the general rule of failure observed in northeast Thailand, Laos and Cambodia, i.e. examples of irrigation projects deemed ‘successful’ or ‘sustainable’ and, where possible, to visit them to verify the claims. I have invariably found the claims of success/sustainability exaggerated, or in some instances just outdated. I had been made aware of an Australian aid-funded development project in the south of Cambodia and informed that it was succeeding using a pumped irrigation model. I visited Wat Thmey scheme in Prey Kabbas district, Takeo province, with high expectations that finally I might see a project working according to plan. This project that was the one shown to visiting ambassadors and senior dignitaries, with fully one-tenth of the five-year US$45 million budget diverted to its construction and operation. The overall programme was designed to ‘add value’ to agricultural products in Cambodia to ‘solve poverty’.

Armed with some baseline data, I visited this project in March 2017 and again in July 2018. What I found was significant exaggeration of the social and economic benefits, including the numbers of beneficiaries, and a downplaying of its many failings and negative impacts. The inequities created by its development were causing community polarisation and local discord, as the management had essentially been purloined by Hun Sen’s ruling Cambodian People’s Party, and opposition figures had been marginalised, or in some cases denied access to water. The majority of the purported command area and farmers claimed as project beneficiaries were in fact not receiving irrigation from it, but were relying on their own resources to pump water from underground or alternative surface water sources. While the project was still functioning on my second visit, there were clear signs it was heading towards failure without outside assistance (hardly a reassuring sign of ‘sustainability’) because revenue from the declining number of water users was insufficient to cover basic operation and maintenance costs. Yet, as far as Australia’s Department of Foreign Affairs and Trade was concerned, all was hunky-dory, thanks to a five-star report from an evaluation mission that had primarily relied upon data provided by the project and government agencies, which predictably talked in glowing terms and concocted fanciful figures regarding benefits. The authors managed to overlook a catalogue of doubtful practices and assaults on the environment from the scheme’s development and liberal use of dangerous agrochemicals by water users, resulting in knock-on impacts on the poorest and most vulnerable community members, formerly reliant upon wild fish and harvesting of wetlands resources.

When I published an analysis of this ‘model’ scheme and invited comment from the senior DFAT official overseeing its regional water resources projects, who had originally suggested I study the scheme, I received no reply, despite prompting. Later, I heard from a senior programme manager responsible for the irrigation project that he concurred with my observations and conclusions, but there was external pressure to continue offering Cambodian government elites the projects they desired, which inevitably led to a dearth of critical thinking around irrigation investment strategy. In other words, this was little more than a political ‘gifting’ project.

Seen in this light, the hundreds of other donor-funded irrigation projects across Cambodia can be understood as strategic ‘prebendary gifts’, harking back to tributes offered by foreign missions to royal courts across Southeast Asia in return for trading privileges or other economic rewards. As is the nature of this modern expression of an older gift-giving culture, the act is hidden in plain sight and yet not tacitly acknowledged for what each of the parties involved understands as its true purpose. The gift of water, whether from sacrosanct ruler to subject or politician to follower is still very much alive and well.

It is likely that the irrigation sector will continue to be overlooked for the material, symbolic and ideological role it plays in maintaining the status quo in underlying power relations, as much at the local level as the national and regional geo-political levels, unless and until it gets dragged into the light of critical inquiry.

• Tags: David J.H. Blake, Free to read, Mekong River, Michael Buckley