Re-examining the economics, engineering and water management paradigms- An interview with Claudia Sadoff

Director-General, International Water Management Institute, Colombo, Sri Lanka

The UN reports that the world is currently not on track to meet Sustainable Development Goal 6 by 2030. What’s your assessment?

The challenge with SDG 6 is that it is not a direct continuation of the Millennium Development Goals (MDGs). The MDGs focused very much on improving access to water, but SDG 6 is fundamentally different and far more ambitious, because it also looks at the sustainability, quality, and allocation of water, the implications of the way in which we manage water, and the participatory aspects of the way in which water management decisions are made. A straight line continuation of the efforts that were made for the MDGs will not necessarily get us to the SDGs, so we will need to revisit some of the basic assumptions that we have been using about water management if we want to meet both the water services goals and the broader goals around water resources management.

 We need to change the way we manage the economic signals around water to ensure it is used sustainably, to safeguard its quality, to promote its efficiency and productivity, and to allocate it to its best uses.

What approaches or lines of action can change course to get SDG 6 back on track?

We have traditionally not treated water as the scarce resource it is, so we need to change the way we manage the economic signals around water to ensure it is used sustainably, to safeguard its quality, to promote its efficiency and productivity, and to allocate it to its best uses. We also need to look differently at our water engineering paradigm; to consider nature based solutions as well as built infrastructure, but most importantly, we need to move away from a ‘single use’ engineering approach to much more circular water systems.  Finally, we need to revisit our water management paradigms. In the context of unpredictable hydrology and climate change and the restrictions that scarcity is beginning to demonstrate, multi-purpose water use planning has to be much more common, adaptive and flexible if we really want to deliver efficiency and equity, as the SDGs are targeting.

Are there already examples of these new ways of thinking that re-examine the economics, engineering and water management paradigms?

In terms of the water economics paradigm, there is a range of incentives. Reflecting the true value of water through pricing is one, but it is not socially acceptable everywhere. There are charges on effluent that can help to incentivise the sustainability of water withdrawals as well as to improve the quality of the water that is returned back to the environment. There are water conservation incentives, as well as water markets that allow the movement of water between different users on a voluntary basis to more socially productive or highly valued uses. Because cultural norms, economic conditions and regulatory systems vary by country and even among states and smaller jurisdictions, the way water markets operate on the ground is very different, even though the core water conservation purpose is the same. In the Murray-Darling Basin of Australia, for example, each season farmers holding water entitlements (a permanent right to take/use/extract a volume of water that is determined based on overall water availability) decide whether or not it will be more profitable to grow crops with their allocated water, or sell some water and reduce crop production.

In terms of engineering, there are very exciting examples of integrating natural capital into urban planning, extraordinary circular economy examples in various mega-cities, such as rainwater capture with permeable surfaces and drainage systems, as well as the use of aquifers that underlie cities and that can be recharged with treated wastewater. We are seeing examples of water reuse at different prices for different uses, so that water can be produced from treated wastewater or desalination.

In terms of the water management paradigm, there are highly functioning river basin organisations, laws and treaties, that recognise that the uncertainty of water requires flexibility in terms of water allocations; differentiated drought pricing policies that would adapt to uncertain hydrological extremes, and a general recognition that the adaptive management of water needs to be built into the institutions, the water rights regimes and the water allocation regimes that we have, because we are more often facing scenarios that fall well beyond what has historically been considered the norm.


In some corners, there’s this strong notion that nature based solutions cannot respond to the pace at which many developing countries are sprawling and the water challenges that come with it. For example, the consideration of the extensive land requirements of wetlands and other nature-based solutions. What’s your view?   

One of the most interesting aspects of thinking through that question is that there is an assumption that you have a direct trade-off between keeping land in its natural state, as natural capital, and developing the value of land. When rapidly developing cities, that may encompass farmland or wetlands, begin to urbanise that land, draining wetlands and building over them, there is not much recognition of the value that is being lost when those natural capital assets are being undermined.  And the truth is that we know that green, liveable cities are highly desirable. You find better air quality, higher property values, and often lower crime rates and lower incidence of mental illness in areas with water and green spaces nearby. Green spaces are also very effective in terms of floods control and recharge of aquifers to avoid landslides.

The notion that nature-based solutions only work where extensive land is available is challenged by several experiences around the world. In the Netherlands, one of the most densely built countries in the world, water resilience goes hand in hand with urban planning, which values this type of infrastructure not just for the added resilience but also for their potential to improve well-being. The Eendragtspolder in Rotterdam is a reservoir for floodwater, but also a popular retreat for its bike paths and water sports. In Singapore, where high-density urban development is the norm, the Active Beautiful Clean waters program developed by the Public Utilities Board provides reference to developers on how to implement nature-based infrastructure and has contributed to a greening of public and private spaces as well as increased resilience to urban flooding. Finally, let’s not forget that many nature-based solutions such as green roofs and green-blue walls have little or no land requirement and can provide significant water resilience in cities.

 In many of the most developed urban spaces investments are being made to add green spaces that were originally removed. 

This whole idea of affordability of sustaining natural capital or natural ecosystems within urban spaces is something that needs to be revisited. In many of the most developed urban spaces investments are being made to add green spaces that were originally removed. The idea is for developing countries that are in the process of expanding their urban areas to try to mindfully integrate natural spaces in a rational way into their urban planning, and essentially leapfrog many of the cities who are finding that they need to re-invest in green spaces to make their cities more liveable.


You are currently living in Colombo, Sri Lanka. How is the city becoming more adaptive and liveable?

Colombo is a wetland city, and government authorities here are doing a pioneering job in trying to consciously and fully integrate wetlands directly into ‘green-grey’ style urban expansion and planning. The wetlands in Colombo significantly help control floods, supply food sources such as rice, vegetables and fish, and sustain a rich ecosystem in particular for bird life. Colombo has in fact applied Wetland City Accreditation from the Ramsar Convention on Wetlands, which is the intergovernmental treaty that provides the framework for national action and international cooperation on wetlands.


The International Water Management Institute has dedicated to applied research on the safe recovery of water, nutrients and energy from domestic and industrial waste streams. Can you share some of the most representative initiatives and business models emerging from these practices to make wealth from waste?

IWMI has been working for 15 years now mainly to refine this concept of resource reuse and recovery. The waste streams that we see growing are full of resources – both wastewater and municipal waste carry with them tremendous assets that are often released into the environment untreated. If properly treated, however, these waste streams contain water, nutrients and energy that can be safely recovered and returned into productive use. Some of the business models that we have been looking at is a combination of composting municipal waste and faecal sludge, which is particularly important for rapidly urbanising peri-urban areas, where you do not have a matured connected sanitation system, but sludge needs to be removed from residential areas. This combination of composting sludge and food waste can be undertaken in a way that safely produces fertiliser pellets that can capture the nutrients that are inherent in these waste streams and return them to productive uses in agriculture. Here in Sri Lanka we are working with plantation owners of rubber, where these sort of fertilisers can help return carbon to the delicate tropical soils as part of a process that removes hazards from the environment.

There are a lot of business models depending on what resource you need to recover, whether it is biogas, fertilisers or the treatment of wastewater for use in manufacturing or gardens, and different business models that are appropriate for different sewage systems, levels of population and land requirements.

What incentives are needed to help upscale innovations in water reuse?

I think outscaling may be as important as upscaling, as many of the lessons that we are learning come from the most decentralised, modular and scalable systems. There are many economic tools to encourage waste management, economic and regulatory incentives that will compel residents of urban areas to manage their trash and have their waste and sewage collected, and other mechanisms can be created by subsidizing and encouraging adoption of technologies. There are also tremendous opportunities for public-private partnerships (PPP) because these waste streams do become income streams, and if PPP can be established where the creation of the enterprise is made easy and possibly incentivised by the government, they can be financially self-sustainable, and bring a social advantage. Part of the real challenge, however, relates much more to behaviour around perceptions. Waste streams are two sides of the same coin – they are hazardous, and that is why we need to take responsibility for them; but they are also incredibly valuable, if we manage them mindfully and safely, and recover those resources for returning them to productive use.

 Waste streams are two sides of the same coin – they are hazardous, and that is why we need to take responsibility for them; but they are also incredibly valuable, if we manage them mindfully and safely, and recover those resources for returning them to productive use.


Irrigation efficiency is key to mitigate water scarcity, yet scientific evidence suggests that efficiency improvements alone do not deliver the presumed benefit of increased water availability. What type of tools and analysis can support real water savings in agriculture?

IWMI has been working on ‘water accounting’, which looks at the basin wide scale of water fluxes and flows, and the different uses that water is put to across a landscape or basin scale that can account for changes in hydrology, reflux to agriculture, transpiration across different landscapes, or to simply understand how much water there is, what is been used for, and eventually its quality. That level of understanding of the hydrologic systems is what we ideally would have in order to manage water in a truly integrated life-cycle, because any user within a basin system can withdraw water, use it, and some share of it will move back into the system. There will necessarily be trade-offs between users as basins increasingly become closed (that is, a system in which all water is put to some use or another), so really understanding those trade-offs require systems of modelling, accounting, and analytics that are still being developed today. The whole concept of sustainable water use, which is called for in the SDGs, is one in which we need information to assess and understand what the full resource envelope is within each system, so that all systems can interact. Only then can we know if we are managing it sustainably.

What are the next generation jobs in water and sanitation?

The water sector is traditionally considered the purview of engineers, but I think there are going to be important opportunities for data and information professionals to really engage in the way we develop and deliver water services by keeping track of the availability and quality of water. We will want to invest more on behavioural sciences with regards to water management, because these social behaviours will really shape our water future. Understanding people’s perceptions of the value of water, the hazards of dirty water, the acceptability of recycled water will be essential as scarcity causes many of the trade-offs between water users and externalities that are created from one set of users to a part of the society. Water economists will also become an important part of the workforce,  to manage, measure and communicate the trade-offs in the water management decisions that we make. Finally, systems science and ecology are areas that will need to be integrated much more to account for the impact on ecosystems.

 Due to rising uncertainty and scarcity, you can no longer separate the communities of practice between those who deliver water services and those who manage water resources


What is it that you are most excited about to participate at the IWA World Water Congress & Exhibition?

The reason that I’m excited to participate in this conference is because I come from the water resources world and I see that the distance between water resources and water services is something that has finally begun to disappear. Due to rising uncertainty and scarcity, you can no longer separate the communities of practice between those who deliver water services and those who manage water resources; the whole urban water cycle needs to be considered if services are to be sustainably and viably delivered, and if the resource itself is to be managed sustainably and for its best uses. To my mind, the big issue for our global community of practice is how to better integrate water resources management with water services delivery, and to use the technologies and the information systems that are increasingly available in the service of that goal.