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Urban water: when engineering met social science

For a long time, the one and only mission of public water service was to provide the best possible supply, both in quantity and quality. But the increasing stress on water resources and the rise of other environmental issues now force suppliers and local authorities to completely rethink their approach. Technical innovation is part of the solution, but the whole models are to be reinvented. Along which lines?

October 2012
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The urban water issue raises numerous questions: potable water supply and distribution, wastewater sanitation, the interaction between these services and natural resources, between the city and its environment. In the prospect of sustainable growth, these questions have become key issues. They bring together researchers and field players to work on innovative projects such as EAU&3E, in order to develop sustainable urban water management systems.

In Europe as in other places, these projects are implemented in a quickly changing environment, particularly with the public service crisis that is now striking developed nations. In the field of water management, this crisis shows several features. The central debate focuses on the edges of public management versus private management of water supply and wastewater treatment. This issue often carries two other debates. The first concerns the level of centralization or decentralization. The second concerns separate versus integrated management.

This crisis is all the more remarkable that the European model is, on the whole, a very successful achievement. Since the apparition of modern public networks in Europe during the 19th century, a tremendous evolution has shown water distributed, first from public fountains, to now almost universal distribution networks.

Although developing countries still don’t have universal access to water, they do seem to experience a very similar crisis. How to move out of this crisis? To find new answers, one must first take a look back at the conditions that led to develop efficient water service and wastewater treatment.

A brief history of the European model

Europe has beyond doubt one of the best overall water service and wastewater treatment in the world: the water distribution network is one of the tightest, thanks to the population density and to the existence of public service over time. Besides, water consumption is quite contained, compared to the United States where it can reach up to three times the volume.

This success is mainly due to the decisions taken by public authorities during the 19th century to develop new policies inspired by the example of Great Britain. The Continent wouldn’t be able to meet these standards without local authorities capable of assuming the organization responsibilities of these new policies. But the implication of national governments was also crucial. They invested heavily in the implementation of costly infrastructure, supported subsidies and subscription to bond issues, enabled savings banks to grant loans and above all other issues, gave full priority to drinking water over other uses.

This new era started before the discoveries of Pasteur. Back then, most engineers in charge of developing water service were civil engineers. To respond to the urgent needs of great cities, water was brought from increasingly far away distances by transportation structures (aqueducts, tanks etc.) or by pumping deeper and deeper. In Paris, water supply aqueducts would measure between 55km and 173km. The US were able to follow this strategy during a long time, thanks to the abundance of available water resources. In New York, for instance, a drinking water aqueduct was built in 1939 from the Croton Reservoir, 66km from the city. Nowadays, this aqueduct is part of larger ensemble of long-distance aqueducts that brings water from the Catskills-Delaware watershed, over 240km from Manhattan.

However, civil engineering infrastructures have their own limitations. Besides, new techniques have redrawn the infrastructure map. The invention of bacteriology led to sanitary engineering which in turn enabled cities to draw their resources from nearby water supplies.

These techniques were implemented on an institutional basis supported by local authorities. From this new market of water emerged giants such as Veolia or Suez. The progressive adoption of volumetric pricing and the transformation of a basic service into an industrial and commercial service have settled water service as a long-term, self-financed model.

The sustainability of the whole system depends on to the association of a technical model: the pressurized network of treated water; and an institutional framework: the local public service, with its features of equity, continuous access and mutability. The same technical/institutional model was implemented for sanitation purposes. Thus, the gradual generalization of water treatment plants on one hand, and of wastewater sanitation plants on the other, have definitively separated urban water network from water resources, each of these under specific economic and juridical regimes.

This model is currently struck by a deep crisis. In the last twenty years, new questions have appeared in the management of water service. They could soon make the situation unsustainable.

An unprecedented crisis

First of all, we’re talking of a mature industry, where infrastructures have to be renovated gradually, without the help of the initial subsidies. It’s the main cause for the rise of water prices. In France, for example, with a network of almost one million kilometers of water pipelines, the renovation budget could reach 85 billion euros. The global infrastructure is aging fast. According to a recent study led in the Rhône and Mediterranean area including Corsica, the renovation need for the drinking water infrastructure is estimated at 1 billion euros in 2008 – a 50% increase between 2001 and 2008.

At the same moment, the European rules require an increase of new investments in favor of the environment. Within the EU15, the overall cost necessary to meet the mandated goals of the urban waste water directive reaches over 150 billion euros in 10 years! And since sanitation is now paid by the water bill, the cost recovery strategy only tends to inflate water prices. To take back the French example, the average price of water has more than doubled between 1990 and 2008, from 1,5 euro/m3 to 3,57 euro/m3 including sanitation and taxes. No wonder that the European policy is applied so reluctantly and that disputes before the European Court of Justice are so common.

But this isn’t all: new price plans also encourage users to avoid wastes. The aim is to reduce the volume of infrastructure management needed and to protect valuable resources. In fact, in many European cities, the water consumption has steadily decreased since the beginning of the 1990s. This phenomenon is often due to very specific causes. The consumption drop in cities of the “new Länder” in Eastern Germany was particularly impressive because the decrease of consumption per person was further amplified by the massive exodus due to unemployment. In Magdeburg for example, the population decreased by 20% since the reunification and forecasts until 2050 show similar tendencies – a fact that could raise many problems. The decrease in water consumption is such that in some neighborhood, the water stagnates over 25 days in the pipelines before being consumed.

This decrease also affects great cities such as Paris, where the increasing tendency was clearly inverted at the beginning of the 1990s, although the population started to increase again. Between 1990 and 2008, the water consumption decreased by 25%. At a time when the renovation of some network segments cannot be avoidable, it is urgent to analyze the reasons of this decrease: will it go on, at which rhythm? In Paris, four different parameters have been identified as important drivers of this evolution: the expansion of the tertiary sector in the Parisian economy (industries have left the city); the fight against waste in big consumption centers like hospitals; the proliferation of eco-friendly household appliances (washing machines and dishwashers); and last, the impact of weather, in terms of humidity and temperatures.

Today, the decrease of water consumption in private households is clearly observable. We don’t know yet whether it’s a consequence of acute ecological awareness or simply an effect of the price increase. In any case, what could support sustainable growth doesn’t necessarily help: in most European countries, the water price is linked to the volume of water consumed. A decrease – even very slight – makes the incomes drop and forces to rebalance accounts by raising prices. At the end, the situation evolves at the expense of the poorest members of society, who don’t necessarily have the means to invest in eco-friendly water equipment: as stipulated by the European directive, water users must pay the cost of the services they use. This exceeds the basic operating or amortization costs. The stagnation of low incomes in conjunction with the increase of prices raises serious problems of access to water. In low-income households, the cost of water represents up to 10% of the overall budget, whereas it barely reaches 1% for an average salary (1470 euros). In the Niort area, for instance, water-poor households (those for which water represents over 3% of their budget) represent approximately 6% of the population. The issue of “right to water” is not only a problem for developing countries…

Towards a paradigm shift?

These tensions lead unavoidably to a remapping of policies. The autonomy of public services in relation to resources is reconsidered, especially in great urban areas, where the impact on environment is considered to be excessive. The European directive encourages territorial solutions, with policies aiming at preserving water resources both in quality and quantity, rather than investing in costly sophisticated techniques. Following this aim, contracts were made with farmers who work on water catchment basins. These contracts are in average three times cheaper than chemical treatments for diffuse pollution.

A thorough debate on the efficiency of water service should be completed by a long-term approach looking beyond the conventional policy of supply and taking in account both the demand and the environment. The current situation sheds a new light on the possible conflicts between environmental, social and economic issues – that are often treated separately. In order to identify desirable and undesirable effects for water services as well as their causes, one must confront a number of divergent threads simultaneously. Here is a quick overview of the main issues at stake today.

Water consumption over the last twenty years has decreased. But how much longer will this trend continue? And above all, how will public services recover costs with the subsequent decrease of their income?

Aging infrastructures need renovation. But should they be renewed identically or with a reduction of network capabilities in mind? Where will the funding come from?

Low-income households are having a hard time paying their bills, and things won’t get any better soon. What are the solutions to this urgent issue: an internal balance between users or a social support to the poorest?

Does citizen participation to the service management help win or lose time? What are the additional transaction costs? Which other costs are avoided? Besides, aren’t we witnessing a change from conventional town operating scales to concentrations and centralizations at various supra-local scales? What combinations should we adopt between upscaling and downscaling (at the scale of neighborhoods or even individual houses) infrastructures and management modes concerning water service?

A need for multidisciplinary research

This crisis forces us to acquire more knowledge and improve the combination between the different dimensions of urban water sustainability. This effort takes place quite naturally in the debates over sustainable cities. Uncertainties concerning the future demand add to the problem of aging infrastructures and to social issues. At the same time, the traditional governance of water service based on the separation between the supply provided by engineers and the demand expressed by elected officials needs to be revised.

We must therefore acquire better knowledge in the four main fields of sustainability: the famous Three E’s of Sustainability (Environment, Economics and Equity) to which adds a fourth parameter, Governance.

The latter divides in two separate fields: internal governance concerns the reorganizations that aim at improving the way elected officials, technicians and users work together; external governance manages the changes of territorial scale and the coordination of tasks to make the service more resilient. Among the lines of research to explore, several threads correspond to the four issues at stake.

1. Improve the models concerning the possible evolution of water consumption according to various equipment hypotheses and household behaviors. Contemplate the use of alternative resources and urban planning; evaluate their impact on the cost of services. Up to now, most models linked consumption to the price of water and to the average wealth of users; now new data need to be implemented: about the environment, economic activity and climate and on increasingly “micro” scales, by using the information provided by remote-controlled water meters.

2. Improve the long-term management of infrastructures, by implementing technical choices aiming at reconquering the aquatic resources according to the European framework directive. Network managers need to launch a deeper reflection on management modes of technical assets in a historical, long-term perspective.

3. Develop a systematic analysis of the balancing of price offered to users and especially, monitor the effects on the poorest. Within the EAU&3E project, for instance, we developed a computer program that analyzes the effects of price changes on families of different sizes and economic levels, before trying to measure the impact of the new price tariffs and consumption volumes on the general financial balance of the service.

4. Think about implementing a multi-level governance, external and internal, to enable a better resilience of services compared to the global changes and a stronger implication of citizens/users. For instance, shall we build eco-neighborhoods that take water into account, even through a necessary articulation with existing public services?

These research issues can be synthesized and put into relation thanks to a prospective approach of water services in cities. Elaboration of new techniques, invention of new jobs and cross-fertilization of different fields… the management of urban water comes as completely new idea!

Bernard Barraqué
Research Director, CIRED (CNRS, EHESS PSL Research University, AgroParisTech, Ponts ParisTech, CIRAD)
Laure Isnard
Research Engineer, CIRED (CNRS, EHESS PSL Research University, AgroParisTech, Ponts ParisTech, CIRAD)