and wastewater infrastructure need to be revisited in the region, in order to ensure the adequacy of service as well as the appropriate level and means of treatment
12.3 Responses
Regional legal instruments have contributed to the general improvement in access to sanitation and reduced impact of wastewater discharges, notably the EU Urban Wastewater Treatment Directive (UWWTD) (see Box 12.3), as well as the UNECE/WHO Protocol on Water and Health (UNECE/WHO, 2016) (see Box 12.4). Some legal instruments in the region provide for technical progress.
The notion of ‘best available techniques’
(BAT), as defined in the EU environmental legislation relating to industrial pollution, also addresses management methods and the environmental impacts. In the chemicals sector, BAT is used as part of an integrated wastewater management strategy, applying a combination of techniques prioritizing those aiming to prevent or reduce the generation of water pollutants and to recover pollutants at the source. In this context, BAT differs from the ‘best available technologies’ based on which the Parties to the Convention on the Protection and Use of Transboundary Watercourses and International Lakes (Water Convention;
see Section 3.2.1) (UNECE, 1992, entry into force in 1996) are obliged to set limits for wastewater discharges, the latter constituting a set of requirements considering technical aspects (as well as availability), but also financial affordability (UNECE, 2013).
BOX 12.2 OPTIMIZING REUSE POTENTIAL: QUALITY CONTROL OF TREATED WASTEWATER AND EXPLORING ECOLOGICAL SANITATION IN EUROPE AND NORTH AMERICA
Treated wastewater holds significant potential to augment water supplies, even for drinking, and the USA reuses water in major volumes. By allowing detection of chemical and biological contaminants, modern analytical technology and multiple barriers provide the necessary control elements to ensure safe water reuse (Water Science and Technology Board, 2012). A pioneering case of direct potable reuse (DPR) in the USA is the facility of Big Spring, Texas which uses microfiltration, reverse osmosis and UV disinfection. The treated wastewater is mixed with raw water, serving some 250,000 people (Water Online, 2014; Woodall, 2015).
Water scarcity has been an important driver of water reuse, and the matching of water quality to the end use determines the need for treatment. West Basin Water Utility produces five types of “designer” waters for specific uses: irrigation, cooling towers, seawater barrier and groundwater replenishment, as well as two types of boiler feed waters (West Basin Municipal Water District, n.d.). Some water uses are susceptible to be fulfilled with reclaimed water having undergone limited treatment, notably green space maintenance (WssTP, 2013). A lack of risk-based treatment guidelines for greywater and stormwater has been noted to constrain broader use in the USA (National Academies of Science, Engineering and Medicine, 2015). To increase the reuse potential of industrial wastewaters, research and technology development are needed, but also demonstration of the available technologies, as well as combinations of new and existing biological and chemo-physical treatment technologies (WssTP, 2013).
In principle, separation of urine at the source and the recovery of faeces for fertilizer could provide opportunities for both rural households and entrepreneurs, and reduced wastewater treatment could have, for example, energy saving benefits. Interpretations on the use of human faeces and urine vary greatly, even within the EU, from following the same guidelines as for animal manure to prohibiting the practice altogether.
While use of compost from dry toilets and source-separated urine in private gardens may be permitted, use on commercial crops is commonly prohibited (O’Neill, 2015). Driven by aspirations to set up ecological closed-loop processes, ecological sanitation using composting toilets and constructed wetland systems for greywater treatment have been used in ecological settlements (i.e. Allermöhe-East Hamburg, Germany), resulting in the reduction of residents’
water and energy use (Von Muench, 2009). The effective realization of sanitation products’
reuse, and the safe use of the fertilizers it contains require that legislation and policies provide a supportive framework, the related health risks are controlled, related logistical issues are solved (i.e. collection of urine, which will subsequently be turned into a solid form), and that cultural acceptance is achieved (O’Neill, 2015).9
9 The author wishes to acknowledge inputs received from: Sharon Megdal and Susanna Eden (Water Resources Research Center, University of Arizona) on use of wastewater; and Sari Huuhtanen (Global Dry Toilet Association, Finland) on ecological sanitation.
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BOX 12.4 NATIONAL TARGET-SETTING UNDER UNECE-WHO/EUROPE
PROTOCOL ON WATER AND HEALTH: ADDRESSING WASTEWATER CHALLENGES The Protocol on Water and Health to the UNECE Water Convention is a legally binding instrument that requires Parties to set national and local targets covering the entire water cycle, including sanitation. The aim is to protect human health and well-being through improved water management, including the protection of water ecosystems, and by preventing, controlling and reducing water-related diseases. The Protocol’s forthcoming programme of work for 2017–2019 sets an objective to strengthen countries’ capacities and scaling up risk-based management approaches in water supply and sanitation. The Protocol’s cross-sectoral planning and accountability
approach offers a practical framework to translate into specific national targets in order to achieve the ambitions of SDG 6, including notably target 6.3 to halve the proportion of untreated wastewater and to substantially increase water recycling and safe reuse.
Sources: UNECE/WHO (2016).
Contributed by Nataliya Nikiforova (UNECE) and Oliver Schmoll (WHO Regional Office for Europe)
BOX 12.3 EUROPEAN UNION’S URBAN WASTEWATER TREATMENT DIRECTIVE The UWWTD (EU, 1991), complemented by the EU’s other pollution control and environmental protection instruments, is a major legal tool that has contributed to the progress visualized in Figure 12.1.
The UWWTD, adopted in 1991, addresses the collection, discharge and treatment of urban wastewater. Its main objective is the protection of surface waters from the adverse effects of wastewater discharges. This is achieved through the requirement for collection and treatment of wastewater in all settlements (agglomerations) with a population equivalent, or p.e.,10 larger than 2,000. The UWWTD provides for the biological treatment of wastewater (secondary treatment) in agglomerations larger than 10,000 p.e. or even smaller. In catchments with particularly sensitive waters (covering nearly 75% of the territory of the EU), such as those suffering from eutrophication, tertiary wastewater treatment can be required. The UWWTD laid out a gradual implementation schedule which requires systems in the largest agglomerations (and with potentially the largest impact) to be made compliant first.
Based on datasets submitted by 28 EU Member States, covering more than 19,000 agglomerations above 2,000 p.e. and generating a pollution corresponding to 495 million p.e., the European Commission assessed the overall compliance rate at 88%. An additional EUR 22 billion investment is forecasted, which will allow EU Member States to fully implement the UWWTD. In addition to investment, one of the main challenges to implementation is long-term planning (EC, 2016b). Where implementation of the UWWTD is well-advanced and combined sewerage systems are used, stormwater overflow can become more significant as a source of diffuse pollution. Therefore, reducing such overflow appears essential for improving compliance rates (Milieu, 2016).
While compliance is a challenge, especially for the recently acceded countries, it is also an opportunity for improvement (Michaud et al., 2015).
Contributed by EEA.
10 Population equivalent, or p.e., is the unit used to quantify the pollution load under UWWTD. One p.e.
corresponds to the organic load which has a five-day biochemical oxygen demand (BOD5) of 60 g of oxygen per day (Umweltbundesamt GmbH, 2015).
Indigenous leader inspects a contaminated river in the Amazon rainforest
UNECLAC | Andrei Jouravlev
With contributions from: Caridad Canales (UNESCAP); Eduardo Antonio Ríos-Villamizar, Emilio Lentini, Gustavo Ferro, Ivanildo Hespanhol, Jaime Llosa, Julio Sueros and Miguel Doria (UNESCO Montevideo Office); and Miguel Solanes and Shreya Kumra (UNECLAC)