Life on the banks of a polluted river

REACH post-doc, Dr Sonia Ferdous Hoque, recounts a recent visit to one of the most polluted stretches of Bangladesh’s Turag River.

Rapid industrial growth attracts the rural poor to Dhaka City, Bangladesh. Image: Nushrat Yeasmin/REACH

During the past few decades, millions of poor people have migrated to Bangladesh’s capital city in search of work at the hundreds of ready-made garment (RMG) factories located along the Turag River. The rapid growth of the RMG industry – the largest export revenue earner for Bangladesh – has significantly boosted the country’s economic growth. However, at the same time, rampant discharge of untreated waste has polluted the Turag to such an extent that it is jeopardising the water security and health of workers and communities living on the riverbanks.

Our recent visit to low-income settlements along the Tongi Khal, the most polluted section of the Turag, revealed the hardships experienced by people who lack access to safe water for their daily drinking and domestic needs. Groundwater from deep boreholes, provided either by the local government or non-government organisations, is often the main source of water. These boreholes are equipped with electric pumps that draw water from the aquifers to overhead storage tanks. However, while water from these boreholes may be sufficient for drinking purposes, households often have to rely on surface water for other domestic needs.

Women in low income settlements along the Turag River use the polluted water for washing dishes and laundry. Image: Nushrat Yeasmin/REACH

We saw diverse water use behaviour between and within these communities, and across seasons. In one of the communities we visited, women said that they never use river water during the dry season as it is “dirty, smelly and disgusting”. However, during the wet season, when the water level rises, most of them prefer to wash and bathe in the river to avoid the hassles of collecting water and waiting in long queues. In another community nearby, we saw a number of women and children washing their dishes and clothes using the river water. The river was visibly polluted with chemicals, plastic bags and household waste. More alarmingly, there were hanging toilets just beside these water use points. Water from the small number of boreholes is sometimes used for rinsing the dishes or clothes after washing in the river.

Hanging toilets discharge human waste directly into the Turag River. Image: Nushrat Yeasmin/REACH

Improving water security for these low-income communities requires measures to stop the indiscriminate discharge of untreated effluent into the river. Effluent Treatment Plants (ETPs) are mandatory under existing laws; however, such environmental regulations are poorly enforced. Lack of financial capacity or reluctance to bear maintenance and operating costs, combined with a general disregard for environmental degradation, are often the reasons behind not having or running full capacity ETPs. While reducing pollution at source may improve water quality over the long term, with positive implications on human health, ecosystems and agriculture, achieving universal drinking water security will also require new infrastructure, possibly through construction of boreholes and small piped water schemes.

The REACH programme’s observatory Water security for an urban river aims to understand these hydrological and public health risks in stretches of the Turag River. We will explore how these risks, in turn, may affect industrial productivity due to avoidable illnesses faced by poorer residents of the area, particularly women working in these factories. The research will provide new models and tools for assessing the efficacy of pollution reduction initiatives at source and the impacts of different development interventions on the water security risks. Outputs will specifically enable decision-makers to prioritise investment plans to maximise returns in terms of water security risk reductions.

This blog was originally posted on the REACH website.

The Angola Low and Southern African rainfall in climate models

New research by Callum Munday, DPhil student at Oxford University’s School of Geography and Environment, sheds light on complex southern African climate dynamics, offering hope for improved regional climate prediction.

Understanding the 21st century changes in the patterns and characteristics of Southern African rainfall is critically important. The region’s socioeconomic activity is closely tied to rainfall and its variability: agriculture production is predominately rain-fed rather than irrigated, while electricity production is largely derived from hydropower e.g. in Zambia hydro accounts for almost all power generated.

Climate models are the best tools we have to predict future changes in rainfall. Unfortunately, in Southern Africa, the latest generation of more than 20 climate models vary greatly in their estimation of historical rainfall (the wettest model is 1.5 times wetter than the driest model). Most of the climate models also tend to overestimate rainfall compared to observational records. This poses a problem: which models can we trust for projecting future climate change?

The first step in addressing this problem is to understand why models differ in their simulation of rainfall in the present day. Our recent work, as part of the UMFULA climate project, attempts to address this question by looking at how well the range of models simulate the Angola Low; an important regional circulation feature.

The Angola Low is a low pressure system which is anchored over Angola and northern Namibia. In the summer months, December to February, it acts like a broker between the wet, tropical African region and the drier subtropical region. When active, it spins clockwise and diverts moisture in low levels of the atmosphere southward from the wet tropical area to the dry subtropical area. Our hypothesis was that wetter models would have a stronger Angola Low than drier models because more moisture would be transported into the subtropics in these models.

Our results supported this hypothesis. In the summer season, between 40 and 60% of the variability in model rainfall is associated with the strength of their simulated Angola Low. Wet models also simulate enhanced moisture transport from tropical to subtropical Southern Africa. Interestingly, the observationally-based reference datasets (“reanalyses”) simulate a weaker Angola Low than most models and are closer in their rainfall climatology to the drier models in the ensemble. This might suggest that drier models are producing a more realistic estimate of Southern African climate, although better observations of the Angola Low are needed to be confident in this assertion.

We are continuing this work by investigating in greater detail how the Angola Low affects rainfall in Southern Africa both in the present day and in the future. This work will help to identify credible models for projecting future climate change. These projections can be used to inform adaptation strategies ahead of climate change in the coming century.

This research is part of Callum’s DPhil, supervised by Richard Washington, and funded by the National Environmental Research Council (NERC). The work was carried out under the Future Climate for Africa UMFULA project, with financial support from the UK Natural Environmental Research Council (NERC) [Grant ref: NE/M020207/1], and the UK Government’s Department for International Development (DfID).The full paper can be found here.

Reforming water abstraction in the UK: a parliamentary perspective

Jerome Mayaud, DPhil student at Oxford University’s School of Geography and the Environment, shares his experience of a recent UK Government posting.

It can be daunting for both policymakers and academics to interact productively. Luckily, the UK’s Parliamentary Office for Science and Technology (POST) is designed to bring scientific research to parliamentarians (MPs and Lords) in short, accessible formats, primarily through four-page policy briefings called ‘POSTnotes’. In the spirit of accessibility, POSTnotes are freely available to the public, and can be useful sources of information for researchers too.

I received funding from the Natural Environment Research Council (NERC) to undertake a 3-month fellowship at POST starting in September 2016. This involved producing my own POSTnote on ‘Reform of Freshwater Abstraction’. The topic was very different to what I normally study for my PhD, so it provided a fascinating insight – from right in the heart of Westminster – into the Government’s proposals to reform the UK’s abstraction regime.

Freshwater resources in the UK are under increasing pressure. While total freshwater abstraction has declined by 15% since 2000 (mainly within the electricity industry), demand for water will likely increase over the coming decades due to population growth. Climatic changes, although uncertain, could also contribute to dwindling freshwater supply, due to a reduction in summer rainfall and increased evaporation from surface water. By the end of the century, serious droughts like that of 1975/6, when standpipes were installed in parts of the country to ration water, could have a 1 in 10 annual chance of occurring. Without adequate quantity and quality of water, the ecology of freshwater bodies may deteriorate. There could be tough economic consequences, too: Water UK estimates that imposing the most severe water restrictions will cost the UK economy £1.3 billion per day.

The current system for licensing water in England and Wales was introduced in 1963. At the time, water supply seemed ample and there were fewer concerns about the environmental effects of abstractions. Today, the system is dated and inefficient, and too inflexible to both protect freshwater environments and to meet future business and public water supply needs. As a result, the Department for Environment, Food and Rural Affairs (Defra) and the Welsh Government have proposed reforms to the regime that should be implemented by the early 2020s. Their focus is to link abstraction volumes more closely to water availability.

An interesting proposal is for the abstraction system to be managed collaboratively by both abstractors and regulators, using rules adapted to the needs of each catchment. The most water-scarce catchments (less than a third of the total) will be designated as ‘enhanced catchments’, with specific rules for environmental controls and trading of permits. In these enhanced catchments, abstractors will be provided with a proportion (or ‘share’) of the total available water, as well as well as short-term allocations based on these shares. This would allow a range of pre-approved trades to occur quickly and easily, including ‘put and take’ water transfers (e.g. from reservoirs and re-use schemes). Trading setups are likely to vary by catchment, but will be based on an electronic system that allows water prices to be agreed between the buyer and seller directly.

In theory, trading reduces adverse environmental and economic effects in times of water stress, and may encourage efficiency and promote innovation. Australia is often held as an example of how the introduction of tradeable licences has led to efficient new usages of water. However, the extent to which this can be attributed to trading is disputed, and some commentators have cast doubt on the applicability of the Australian experience to the UK. For instance, Australia’s large rivers lend themselves to being dammed far better than smaller rivers in the UK, so water can be stored, regulated and allocated over much longer timescales. Challenges of trading include the possibility of large abstractors dominating the market at the expense of smaller users, the emergence of hoarding and third party ‘water brokering’, and a perverse increase in abstraction that could result from reduced prices following efficiency gains. It is clear from the Australian case that strong regulation and clear communication of information, risk and permit reliability will be essential for establishing a functioning water market in England and Wales.

Alongside the proposed abstraction reforms, Ofwat, the water regulator in England and Wales, expects water companies to build ‘resilience’ into their business plans. A ‘twin track’ approach will likely be needed to improve water security in England and Wales, with strategies that both enhance supply (e.g. transfers between rivers, new reservoirs and dams, desalination, effluent reuse) and reduce demand (e.g. smart metering, improving building standards, tackling cultural and behavioural barriers).

The latest focus on resilience also encourages companies to use innovative modelling to improve evidence around future risks. Water companies can stress-test policy options, or assess them against multiple success criteria over hundreds of scenarios using approaches such as Robust Decision Making (e.g. as is done by Water Resources in the South East, a regional grouping of six companies).

For a fully integrated abstraction system to succeed, however, water companies should not work in isolation from other stakeholders. The UK Climate Change Risk Assessment 2017 evidence report promotes the notion of ‘collective arrangements’ for water, such as farm-based water-sharing schemes and river catchment management groups. Indeed, over 100 catchment partnerships (composed of 1,500 organisations) already exist in the UK, potentially forming a basis for Defra’s catchment-based approach. The abstraction system may also benefit from interactions with land management, for instance through rewarding land users that conserve water and invest in natural storage. Exit from the Common Agricultural Policy (CAP) could present an opportunity to introduce new incentives for land managers to improve water efficiency in the UK.

Researching my POSTnote was a challenge, especially when it came to balancing some very opposing views on a subject matter that is inherently highly political – access to water. But it was also an incredibly exciting time to be in Parliament. The ‘corridors of power’ were abuzz with the fallout from Brexit, Theresa May’s appointment as the new Prime Minister, and of course Donald Trump’s accession to the White House. It is our duty as researchers to connect with the policy world to a certain extent, and if done carefully and creatively, policy engagement can be rewarding and enriching. I would highly encourage any PhD students with an interest in policy to apply to RCUK’s policy internships scheme.

Social safeguards in Chinese-led dam projects in Indochina

New research by Oxford DPhil student, Julian Kirchherr, documents how Chinese dam builders are increasingly adopting international standards in response to dam opposition.

Chinese dam developers are at the forefront of global hydropower development, driving significant dam construction, particularly in Africa and Southeast Asia. New research, led by Oxford doctoral student, Julian Kirchherr, published in Energy Policy, documents the change in social safeguard norms in Chinese-led dam projects in Myanmar, Laos and Cambodia.

The paper, published as part of Kirchherr’s doctoral research at Oxford University’s School of Geography and the Environment, found that Chinese dam developers increasingly take international social safeguard norms into account when developing dam projects. This change in approach can be attributed to social mobilization in opposition to Chinese dam construction, with the suspension of the Myitsone Dam in 2011 considered a particular game changer for Chinese dam developers.

“Chinese dam developers would never have believed that the governments in Myanmar, Laos and Cambodia would consider suspending a Chinese-led dam project”, said Kirchherr. “This perception changed thanks to the Myitsone Dam.”

Despite the opposition to the Myitsone dam, the Government of Myanmar has not yet cancelled the project. In a recent commentary published in the Myanmar Times, Myanmar’s leading daily, Kirchher, and co-author Matthew Walton, Aung San Suu Kyi Senior Research Fellow at St Antony’s College, argue that the project should be aborted:

“Continuing it would be terrible for international safeguards”, said Kirchherr.

Kirchherr’s earlier DPhil research highlighted that a lack social safeguards are a root cause of massive anti-dam-protests. His work described the strategies implemented by anti-dam-movements in Myanmar and Thailand that culminated in the suspension of projects, ultimately encouraging Chinese developers to adopt international social safeguard norms.

Kirchherr, recently took up an assistant professor position at the Faculty of Geosciences, Utrecht University, where he will launch a research group focussing on the circular economy as a vehicle for business sustainability.

Lakes as well as oceans: understanding new evidence of the impact of climate change in the Early Jurassic Period

Earth Sciences DPhil student, Weimu Xu talks to the Oxford Science Blog about her new paper, recently published in Nature Geoscience.

Geochemical and biological research offers academics a window into earth history, enabling them to piece together events that occurred before records began. Much of our understanding of past climate change is based on geology, in particular the study of sedimentary rocks deposited in the oceans.

The paper that first recognised and defined Oceanic Anoxic Events (OAEs), written by Oxford professor Hugh Jenkyns and an American colleague, is considered a seminal contribution to geological history, that led the way to numerous studies on the effects of oxygen starvation in the oceans.

The discovery of organic-rich sediments, often described as black shales, at numerous deep-sea drilling sites during the early 1970s, led to the wider acknowledgement of the oceanic impact of climate change. At certain intervals during the Jurassic era, huge bouts of volcanic activity triggered increased concentrations of atmospheric carbon dioxide. This then caused a knock-on greenhouse effect, raising the sea-surface temperature and reducing oxygen levels in large parts of the ocean.

At the same, oceans benefited from increased nutrient levels, and as a result marine algae and bacteria bloomed. As they died, these organisms were preserved in sediments that formed on the sea floor and over time changed into source rocks for oil. It is these phenomena that illustrate the causes and effects of OAEs.

New research, published in Nature Geoscience, has for the first time examined the impact of this type of sediment deposition in lakes. The study demonstrates that lake environments responded in a similar way to climate change, developing the same anoxic conditions as in the oceans.

Led by Earth Sciences post-graduate student Weimu Xu, the work offers insight into how environmental factors have affected lake formation throughout the ages. Weimu and the team studied sediments from one of the largest lakes in Earth history – double the size of England and three times the size of Lake Superior – the largest lake (in surface area) in the world today. This ancient lake formed rapidly in the Sichuan Basin, China, as a result of Toarcian (Early Jurassic) climate change, about 183 million years ago.

Weimu spoke with Science Blog about the study’s key findings and what they can tell us about climate change today.

What is the key finding that you would like people to take from this study?

The extreme effects of past climatic changes are not limited exclusively to oceans. By dating the lake sediments to the Early Jurassic (Toarcian) period, we were able to show that large lakes formed and were affected in the same way as oceans during an OAE.

As the climate warmed, the continents experienced increased rainfall, creating lake reservoirs, which essentially acted like mini-oceans. Lake organisms became more abundant, drawing-down massive amounts of carbon dioxide from the atmosphere, which was eventually deposited into sediments. Overtime, these sediments became source rocks for oil.

Lake environments represent their own unique challenges. Did you encounter any specifically?

The biggest challenge for us was establishing the age of the sediments found in the Sichaun Basin, and proving that they were of similar age to those that formed in the oceans during the Toarcian OAE. The wealth of organic matter found in marine environments makes it quite easy to date an event, by basing it on a fossil’s geological age. But lakes do not have such fossils, which makes it much harder to determine the age of the sediments found.

A study of this nature involves a massive amount of work. How did you manage such an extensive undertaking?

Fortunately I worked with a great team. This work was led by myself, co-designed by M. Ruhl, H.C. Jenkyns and S.P. Hesselbo and involved a total of 11 people. The project is a great example of collaborative research.

We used three distinct methodologies, which would be impossible for any one researcher to master. Colleagues from the University of Durham applied radio-isotopic dating to establish the age of the sediments and colleagues from the British Geological Survey studied the pollen, spores and algae preserved in the sediments. Finally, to give us even more detail to support the age of the sediments, together with colleagues from the University of Bristol and at Shell Global Solutions International B.V., we applied stable carbon-isotope to analyse the sediments, plant and algae remains. These varied techniques convincingly showed that the sediments found, had formed at the same time as the Toarcian OAE.

We were fortunate to be able to partner with experts in these three fields, and of course our industrial partner Shell.

How long did the research take to conduct?

The study lasted from the first sampling trip in November 2013 to completion of this manuscript in September 2016. We also had to factor in time to get permission to publish the findings, from the oil companies providing the data.

Are there any long-term impacts associated with your findings?

There are definite links between the climatic event identified in the Toarcian and present-day global warming. A better understanding of past climate systems could help predict environmental and ecological changes in a future greenhouse world. While the lake we studied existed in the Early Jurassic period, there are lakes today in African and British Columbia for example, that have been affected by global warming. They are becoming more and more anoxic and some are losing fishery stocks as a result. People fixate on warmth, but anoxia goes hand in hand with warmth.

There’s a certain irony in the fact that the conditions which created oil and gas deposits millions of years ago are being recreated much more rapidly by burning of these fossil fuels.

How would you like to see this work used in the future?

Our study directly links lake formation and sediment deposition to the Toarcian OAE. By studying other lake sediments that were around at that time, researchers could establish if they also link to this event. For a better understanding of major climatic change in other intervals of the Earth’s history, people can also look and see if there were other major lake reservoirs that acted similarly.

It would also be useful to understand the impact, not only of carbon deposition, but carbon burial, during times of major climatic change, and how that impacted coal formation. This is something I am very keen to focus on next.

The paper, Carbon sequestration in an expanded lake system during the Toarcian oceanic anoxic event, can be viewed here.

This post was written by Lanisha Butterfield and first appeared on the Oxford Science Blog.

ITRC researcher wins Lloyd’s Science of Risk Prize 2016

Insurance industry recognises systems modelling tools developed by Environmental Change Institute researchers to support better infrastructure risk management.

Photo: Dr Raghav Pant presents his award-winning paper at the Lloyd’s Science of Risk Prize 2016

Dr Raghav Pant, Senior Postdoctoral Researcher for the ITRC, won the prestigious Lloyd’s Science of Risk Prize 2016 in Systems Modelling. His research paper explored how infrastructure systems modelling can help businesses improve their infrastructure risk management, and was published in collaboration with Professor Jim Hall (Director of ECI, University of Oxford) and Dr Simon Blainey (Lecturer in Transportation, University of Southampton).

Infrastructure owners, operators and insurers face profound socio-economic losses when their assets are exposed to external events, such as extreme weather, that cause serious damage or business interruptions.

Modelling tools for risk assessment incorporate the interactions between infrastructures, people and economy, and assist improved planning for these incidents. Dr Pant’s research provides advanced analytics, with better data for insurers on the vulnerabilities of their insured assets and connected networks. There is a clear financial incentive because such knowledge helps insurers to incorporate pro-active risk management to protect key assets and minimise losses. With his unique modelling, it is possible to look at the impact of different shocks on infrastructure networks, and to use this information to identify, for example, critical assets or the particular risks associated with flooding and other extreme events.

These insights can then be applied widely: improving asset management programmes, revising risk registers or informing investment decisions. Dr Pant said:

“Giving decision-makers better information about their potential risks can build their capacity to plan for the future. Our system-of-systems approach has applications across business and policy, so it’s just as useful for people responsible for maintaining infrastructure assets as it is for those who are planning new infrastructure. The ITRC methodology can be transferred to any general infrastructure context, and is already being applied to infrastructure systems in the UK and in other developed and developing countries.”

The Lloyd’s prize is awarded to the research paper that is judged to best inform the insurance industry on risks and risk management, and in confirming the award, Lloyd’s said:

“The judging panel, comprised of experts from academia and insurance, felt that your paper contained brilliant analysis and research. They felt that the paper adds directly to insurers’ knowledge, and that what it looks to cover is readily applicable and useful.”

Read more

This post was originally published on the ITRC webpage.

Modelling toxic chemicals in Dhaka’s Turag-Balu River

Professor Paul Whitehead provides an overview of a new water quality modelling collaboration – part of the Oxford-led REACH programme’s research in Bangladesh.

Netting fish on the Turag River, with the brickworks in the distance, Dhaka, Bangladesh. Wonderlane/Flickr CC BY 2.0

Pollution in large rapidly developing cities is a major problem responsible for many premature deaths and serious illnesses, especially for women and children. Pollution has been named ‘the silent killer of millions in poor countries’ by the Global Alliance on Health and Pollution.

The combination of high population numbers, insanitary conditions, poorly regulated industrial discharges and untreated domestic effluents has resulted in highly polluted city rivers which pose a significant threat to people using the river water, groundwater and associated water supply systems. Bangladesh’s Turag-Balu River system in central Dhaka is no exception, with over 30,000 factories discharging waste into the river system and 12 million people contributing waste with minimal treatment, as well as agricultural pollution from upstream areas.

The Turag originates from the Bangshi River, the latter an important tributary of the Dhaleshwari River, and flows through Gazipur and joins the Buriganga River at Mirpur in Dhaka District. The Turag receives a huge waste load of industrial effluent from Gazipur and the Tongi industrial area in addition to domestic waste from numerous sources along its banks. The industrial and municipal wastes are the major sources of pollution due to growing industrial development and the poor state of the sewerage and sanitation system, not only around the Turag but also throughout Dhaka City.

A new study of the Turag River system is currently underway, led by Professor Paul Whitehead from Oxford University and Professor Abed Hossain from the Bangladesh University of Engineering and Technology (BUET). The team are gathering new water quality data and establishing some mathematical models for the river systems, which can then be used to evaluate different pollution reduction measures including effluent treatment, flow augmentation and pollution warning systems.

In order to model water quality it is necessary to first model the hydrology of the system. It is clear that the hydrology of the system is highly complex and special attention needs to be paid to the additional flood flows and runoff coming from the upstream Turag catchment as well as from the Brahmaputra River (Figure 1). The extent of the connection with the upstream rivers, including the Brahmaputra River, is difficult to estimate but we have assumed the transfer of water across to the Turag as shown in Figure 1 and we have estimated this flow transfer system.

Figure 1. Reaches and sub-catchments of the Turag-Balu River System around Dhaka (dry season – left, monsoon season – right). The red arrows indicate the directions.

A set of preliminary simulations have been undertaken for the Turag River System with the whole river system spilt into 24 reaches as shown in Figure 1. We have used rainfall data to drive the hydrological model and Figure 2 shows the simulated and observed flows in Reach 10 of the Turag at the confluence with the Tongi Canal. The observed flows match simulated flows but note the observed flow data is only available at certain times of the year in the monsoon period. However, the peak flows and overall dynamics look reasonable, suggesting that the model is a good fit.

Netting fish on the Turag River, with the brickworks in the distance, Dhaka, Bangladesh. Wonderlane/Flickr CC BY 2.0

We have also used the model to simulate levels of nitrate and ammonia in the river. The results show low concentrations in monsoon periods when flows are high and dilute all of the pollution from diffuse runoff and point sources. Much higher concentrations are found in the low flow periods when little dilution occurs.

Once we have further calibrated the model we will investigate future potential change such as the impacts of climate change and socio-economic change on flows and water quality. We will also be able to set up additional models for pathogens and organic pollutants in the river system.

This blog post was originally published on the REACH website.