Decision support for sustainable urban drainage system management ...

Journal of Environmental Management 101 (2012) 46e53

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Decision support for sustainable urban drainage system management: A case study of Jijel, Algeria Abbas Benzerra a, b, d, *, Marzouk Cherrared d, Bernard Chocat a, b, Frédéric Cherqui a, c, Tarik Zekiouk d a

Université de Lyon, France INSA-Lyon, LGCIE, F-69621 Villeurbanne, France c Université Lyon 1, LGCIE, F-69622 Villeurbanne, France d LRHAE, Université A. MIRA, Route Targua Ouzemour 06000, Béjaïa, Algeria b

a r t i c l e i n f o

a b s t r a c t

Article history: Received 20 May 2011 Received in revised form 1 January 2012 Accepted 9 January 2012 Available online xxx

This paper aims to develop a methodology to support the sustainable management of Urban Drainage Systems (UDSs) in Algeria. This research is motivated by the various difficulties that the National Sanitation Office (ONA) has in managing this complex infrastructure. The method mainly consists of two approaches: the top-down approach and the bottom-up approach. The former facilitates the identification of factors related to a sustainable UDS, the development priorities and the criteria available to managers. The latter assesses UDS performance using the weighted sum method to aggregate indicators or criteria weighted using the Analytical Hierarchy Process (AHP). The method is demonstrated through its application to the UDS in the city of Jijel, Algeria. Ó 2012 Elsevier Ltd. All rights reserved.

Keywords: Urban drainage systems Sustainable management support Indicators and sustainability criteria Performance assessment

1. Introduction In Algeria, as in many other African countries, urban drainage system (UDS) managers (in this case the National Sanitation Office e ONA) are facing huge challenges. This situation is the result of the rushed management of rapid urban development. For a long time, UDS have been designed for the sole purpose of meeting the population’s basic needs in terms of wastewater and stormwater transportation. Consequently numerous projects have been implemented with no overall strategy or coordination. Budgets have been allocated to building infrastructure, but future management constraints have neither been taken into account, nor have developments in the service provided by the UDS been accurately measured. Various aspects such as the protection of the environment, economic and financial management, maintenance, drainage system regulations and design standards, and information management have been neglected (Cherrared et al., 2007, 2010; C.N.E.S., 2000). In Algeria, the National Sanitation Office (ONA) faces the challenge of taking the government’s recent strategic focus on

* Corresponding author. INSA-Lyon, LGCIE, F-69621 Villeurbanne, France. Tel.: þ33 04 72 43 64 68. E-mail addresses: [email protected], [email protected] (A. Benzerra). 0301-4797/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. doi:10.1016/j.jenvman.2012.01.027

sustainable development (Loi n 05-12 du 04 août, 2005) into account in UDS. It needs to identify the concrete actions which will result in sustainable management. The multi-dimensional requirements of a sustainable development approach (economy, society and environment), as well as the lack of structured methodology and information at various levels of the hierarchy make this task particularly difficult (Ugwu and Haupt, 2007). This task is even more difficult for a country such as Algeria which needs to develop its urban infrastructure in order to increase its economic growth. In order to achieve sustainable management, it is first vital that the ONA’s management capacities are improved. Another prerequisite for achieving this is that the sustainability of the UDS can be measured or be quantified. This requires a set of criteria or indicators for sustainability to be built and approved by stakeholders. Our aim is therefore to develop a methodology to measure the sustainability of Algerian UDS and thereby to help improve how they are managed and developed. The methodology involves all partners in the process of choosing the relevant aspects of sustainable management and in defining the corresponding objectives. Since the 1987 report of the Brundtland commission (WCED, 1987), the concept of sustainability has become increasingly popular. The principle of sustainability can be applied to a variety of areas, including the sustainable management of UDS. The

A. Benzerra et al. / Journal of Environmental Management 101 (2012) 46e53

Agenda 21 resolutions were an outcome of the United Nation’s Conference on Environment and Development (UNCED, 1992) held in Rio de Janeiro, Brazil indicated that the concept of sustainability should be taken into consideration in urban water management. However, the detailed method of how to apply sustainability to decision-making in this area is not explained. In order to make the application of sustainability to urban water management possible, local Agenda 21 programs were set up at national (MATE, 2002) and continental level across Africa (NEPAD, 2001). However, the process of translating national sustainability objectives into practical actions within specific projects remains challenging. Over the last few years, many studies have looked at the methodology for assessing the level of service provided by an UDS. Most of these studies have focused on developing indicators to measure the performance of wastewater treatment plants (Lundin and Morrison, 2002; Quadros et al., 2010) or wastewater treatment systems (Balkema et al., 2002). Others studied the performance in terms of service provided (Kolsky and Butler, 2002; Geerse and Lobbrecht, 2002; Foxon et al., 2002; Matos et al., 2003; GuérinSchneider, 2001). Some studies take a more pragmatic approach to assess the sustainability of storm drainage networks, in particular by measuring performance in comparison to alternative techniques (such as retention and/or infiltration systems) (Ellis et al., 2004; Barraud et al., 1998; Dechesne et al., 2004; Moura et al., 2006, 2010). Most of these studies focus on the qualitative definition of indicators in the design phase but not on their quantitative assessment. Others looked at decision support tools. These fall into two main categories: At structural level: an overall vision of the system is integrated by focusing on a specific structure. Examples of this category include the ECOPLUIES project (Moura, 2008) dedicated to infiltration structures, CARE-S (Saegrov, 2006) and INDIGAU (Le Gauffre et al., 2007) which focus more specifically on performance indicators for the assets management of urban drainage networks; At the level of urban water management systems: The DAYWATER (Thévenot, 2008) and SUDS projects (Sheffield) (Kennedy et al., 2007) focus on stormwater control techniques at the source. The Triple Bottom Line (Taylor et al., 2006) and SWARD projects (Ashley et al., 2008) focus on the sustainable management of drainage networks. None of these projects correspond to the specific situation in Algeria. However, each one contains relevant and useful elements. Generally speaking sustainability studies contain finely-tuned indicators specifically adapted to a certain case. Therefore, locally defined performance indicators are required for our specific case. It is important that the methodology is adapted to the national situation in order to convince the decision-makers that it should be implemented. In our case, national interests will strongly influence the methodology used. Our study is based on the work of LGCIE (Toumi and Chocat, 2004; Chocat et al., 2007; Shuping et al., 2006; Granger et al., 2010). It also forms part of a commitment to develop a methodological tool to support the sustainable management of UDS in the Algerian context. The Algerian UDS is characterized by a lack of precise data on the drainage network, hydraulic malfunctions (flooding, dry weather overflow of sanitary sewage), pollution of the natural environment, the comfort and safety of urban populations etc. This paper describes a decision support methodology for sustainable UDS management. The method used to aggregate the performance of indicators and assign an overall performance

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score to each objective is presented. An example application is shown on the UDS of Jijel, a city in north-eastern Algeria. 2. Methodological approach The approach first requires the different themes concerning the sustainable management of the system to be identified. The priority objectives for the UDS are then set for each theme. Each objective is made up of a set of criteria, assessed using performance indicators. This top-down approach makes it easier to describe the selected objectives and to choose appropriate indicators. In order to prepare for the discussions regarding the themes related to UDS sustainability, we first recall the concept of sustainability including urban water management: a sustainable urban water system must provide the services required from a longterm perspective whilst protecting human health and the environment, with the minimum use of rare resources (Lundin, 1999). In order to evaluate UDS sustainability we must first answer the following questions: What are the system boundaries and available data for the UDS under consideration? How can useful indicators and sustainability criteria for decision support be identified? How can the raw data collected in the system be translated into a performance score which can be used later for decision support? These three questions are explored in the following subsections respectively. The proposed methodology for assessing UDS sustainability is structured in two main approaches: (i) Identification and description of the UDS indicators (top-down approach) and (ii) assessment of the UDS’s performance (bottom-up approach). The top-down approach is to define, in liaison with the system’s manager, the general requirements the UDS should meet in order to be considered a sustainable system. These requirements are identified as themes. These themes are then broken down into objectives. Criteria are then selected to measure the extent to which these objectives are met. Finally, the indicators are used to measure the criteria. The bottom-up approach involves developing aggregation methods which make it possible to determine an overall score for the whole system performance from the values obtained from the indicators. 2.1. System boundaries and data Currently, cities function using many technical systems (drinking water, urban drainage, roads etc.). These urban components interact with each other in a very complex manner. In this paper, we only focus on UDS with the aim of obtaining an overall vision of the system. The system includes not only the urban drainage network and its components (structures and urban basins) but also the wastewater treatment plant, the technical and political organizations that manage the system, the discharge environment and the city with its associated technical and organizational systems (Bonièrbale, 2004; Lundin, 1999). Furthermore, decision support for UDS management requires several data sets (i.e. from the drainage network, the wastewater treatment plant, the discharge environment etc.). It is therefore important when developing such a method to take into account data availability. This is particularly the case in Algeria as little data is available due to the absence of a monitoring body. The ONA is currently training its staff in this area and, in parallel, is using a group of foreign engineering companies to obtain data. This task

48


also requires cooperation between various administrative departments (various departments of the wilaya (Algerian administrative province) including Hydraulics, Environment, Health, Population, Urban Planning and Construction; local services; and the company responsible for drinking water management (Algérienne Des Eaux)). 2.2. Identification of indicators and sustainability criteria UDS sustainability criteria and indicators were identified, inspired by the research dealing with the issue of UDS management in Algeria (Benayada and Kettab, 2005; Cherrared et al., 2007; Kettab et al., 2008; Toumi and Chocat, 2004). Recent government directives on integrating sustainable development into project management (C.N.E.S., 2000, 2007) and the research literature on achieving sustainability and decision support also formed the basis for this paper. Defining sustainability requires the analysis of all the different aspects of a UDS. Hence a descriptive approach is implemented which describes the system in several parts: sanitary, flood protection, environmental, economic and service management. Fig. 1 summarizes the selected themes used in this approach. These themes make it easier for the service manager to identify the levers for a sustainable UDS management. Each theme requires critical analysis and a detailed description. This analysis takes into account both UDS operations and the resources available to the Algerian management services. The theme is then broken down further. Each theme is associated with a series of objectives. An objective represents a priority in terms of the system manager’s operational requirements. Each objective corresponds to a basic function of the UDS. It can either be set for a physical phenomenon or related to activities or organizations. Under each objective, one

or more criteria are then given in order to assess the level at which the corresponding function is considered to be fulfilled. These criteria constitute both a link between the objectives and the performance indicators and the reference indices for improving UDS management (Foxon et al., 2002). The summary of the themes, objectives and criteria drawn up by the LGCIE (Laboratory of Civil and Environmental Engineering, France), the LRHAE (Laboratory of Applied Hydraulics and the Environment, Algeria) and ONA managers in the city of Jijel, (Algeria) is shown in Fig. 1. A set of criteria has been identified (Shuping et al., 2006) in order to help select the most relevant indicators. The performance indicators associated with the criteria are not presented in this study. 2.3. Performance assessment The aim of our methodology is to provide a management chart to support the decision-making process. When doing this, we face two contradictory requirements: To not lose sight of the multi-dimensional nature of sustainability; To provide an overall vision of the service provided by the system. We used the method of partial aggregation which aggregates the indicators into criteria and then the criteria into the performance assessment of objectives. The multi-dimensional nature of the assessment is preserved at the objective level. The main procedure of the method is given as follows:

C1: Overall quality C2: Suitability for use to produce drinking water O1 C3: Suitability for use for irrigation Do not alter water O15 C4: Suitability for use for fishing quality of O2 C5: Suitability for use for swimming Prepare for the transition to receiving water Improve the C6: State of eutrophication an integrated urban water safety of urban management system C7: Reduce the risk of accidents resulting from inhabitants O14 malfunctions in surface drainage structures O3 C32: Reduce financial losses T1 Reduce the UDS’s Improve the T8 C8: Limit the risk of flooding impact on the local comfort of urban UDS inspections C9: Reduce odor pollution economy inhabitants in relation to Prospective its target C10: Reduce contamination O4 O13 environments by wastewater T7 Guarantee the health T2 Improve Economic and and hygiene of users C11: Reduce the discharged mechanisms for C31: Measure spending and Operational financial pollutant load funding UDS improve its effectiveness status of management O5 C12: Guarantee The TS yield UDS of UDS UDS C30: Adapt spending Ensure the correct O12 C13: Minimize overflow pollution to needs sustainability functioning of load (above standards) T6 Improve investment T3 Treatment System C29: Improve the C14: Produce reusable by-products and operating costs Quality of (TS) Institutional processing of complaints and re-use them UDS framework operation O11 C28: Improve the C15: Confine what is not reusable O6 T4 of UDS T5 recording of complaints and/or dangerous Improve user Ensure the quality HR Structural relations of the design and C23: Manholes quality of management C16: Improve the collection rate construction of the O10 UDS C24: Gully inlet UDN C17: Ensure the correct design and Ensure the O7 construction of wet weather C25: Overflow structure monitoring and Improve the collection structures maintenance of O9 C26: Network governance of O8 structures C18: Ensure reliable services for users Guarantee the skills C27: Equipments Guarantee the draining services of the personnel C19: Improve the connection rate health and safety responsible for the to the TS Legend: of personnel UDS C22: Improve staff training C20: Reduce the number of occupational accidents Ti : Theme i C21: Improve the protection of personnel Oi : Objective i against contamination from wastewater Ci: Criterion i UDS: Urban Drainage System UDN: Urban Drainage Network Fig. 1. Summary of the selected themes, objectives and criteria.


Step 1: to assign each indicator a value that contributes to the criterion; Step 2: to aggregate the indicators for each criterion in order to measure the overall performance of the criterion; Step 3: to aggregate the criteria to measure the level at which the objectives are met; Step 4: to assess the level of satisfaction with regard to a specific theme using the assessment results for each objective. We have maintained a multi-criteria assessment for the last step but have chosen to use an aggregation procedure for the second and third steps. This method requires a common scale for assessing the criteria and objectives in order to then manipulate them using simple operators (sums, averages, etc.). It is therefore important to first transform the estimated value for each indictor (indicator status) in order to give it a score on a standardized performance scale. 2.3.1. Performance scale The performance assessment starts by converting the values of indicators to performance values in certain scale. The scale should be defined finite, quantitative and scalar. The scale from 0 to 1 has been chosen in our case with 1 representing the best performance and 0 representing the worst. In order to transform the initial measurement of indicators into scores between 0 and 1, performance functions should be built first using standards and, where these are not available, the ONA experts’ recommendations. Fig. 2 shows an example of the performance function for the TSS (Total Suspended Solids) indicator to assess the quality of the discharge environment according to the SEQ-eau (Water Quality Assessment System) (Babut et al., 2003). This performance function corresponds to one of the indicators in criterion C4 of objective O1 (Fig. 1). When the concentration of TSS is less than or equal to 50 mg/l the performance values vary linearly between 0.6 and 1; when the TSS is above the threshold of 150 mg/l, the performance is zero. Performance functions of this type were built for each indicator. 2.3.2. Selected aggregation method The most frequently applied aggregation methods include: complete, partial and local aggregation (Roy and Bouyssou, 1993; Ben Mena, 2000). Complete aggregation is used in our case study based on the single criterion. Complete aggregation seems the most appropriate method for aggregating all the indicators corresponding to one common criterion. This corresponds to the context of our study and the ranking of the criteria and objectives developed (Fig. 1). Furthermore, this choice does not compromise the multicriteria nature of the overall assessment as the scores assigned to each objective are still available. There are a wide variety of complete aggregation methods, such as:

49

Pairwise comparison (Limayem and Yannou, 2004); Weighted sum (Roy and Bouyssou, 1993); Multi-Attribute Unity Theory (MAUT) developed by Keeney and Raiffa in 1976 (Bryhn et al., 2009); Or other mathematical functions such as that developed by Nassar et al. (2003), etc. The weighted sum method is used for its clarity and simplicity. It is a widely used method amongst the aforementioned techniques (Ben Mena, 2000). The main drawbacks of this method are: I) the possible compensation between indicator scores in some situations and II) its high sensitivity to changes in scale. The compensation is acceptable as the aggregation is implemented between elements of the same nature (belonging to the same objective). The second drawback is reduced when the same scale is used to assess all the scores to be aggregated, as is the case here. The performance of criterion Cj is assessed using the following equation:

PCj ¼

n X

PIji $wji

(1)

i¼1

where: PCj: performance value of criterion Cj; n: the number of indicators considered in criterion Cj; PIji: performance value of indicator Ii in criterion Cj; wji: value of weight factor for indicator Ii in criterion Cj. The aggregation approach is similarly implemented for the objective assessments. 2.3.3. Weighting method In this study, the weight was calculated using the AHP method. AHP is a multi-criteria decision support method which allows decision-makers to specify the relative importance of different elements. In the case of a complex problem such as our case study, the method is applied in a hierarchical manner from the indicator level up to the objectives level. The AHP method is based on pairwise comparisons of judgment. It integrates the importance of the criteria and the indicators into one overall score for the objective. Although AHP method is widely used (Ramanathan, 2001; Herath, 2004; Ugwu et al., 2006; Ugwu and Haupt, 2007; Hajkowicz, 2008), it has also been criticized (Al-Harbi, 2001). The main criticisms are: The addition of new indicators can change the ranking of existing indicators; The weights are calculated without taking into account variations in the scale of the indicators. However, according to the conclusions of previous studies (Harker and Vargas, 1987; Pérez, 1995; Al-Harbi, 2001), and given the precautions that are taken to overcome the drawbacks (same scalar scale for all assessments) this method is well adapted to our objectives. The procedure for the AHP method is summarized as follows: 1) Define the problem and determine its objectives; 2) Develop the hierarchical structure of the problem: 1st level: define the various objectives for the problem; 2nd level: select the criteria for each objective; 3rd level: assign indicators to each criterion. 3) Construct the decision matrix (see below).

Fig. 2. Performance function TSS for the assessment of water quality in the discharge environment.

The decision matrices are composed of elements aij. The element aij represents the order of preference between indicator/ criterion i and indicator/criterion j. The values of aij are assessed using pairwise comparison (Table 1).

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Table 1 Pairwise comparison for preferences in AHP (Al-Harbi, 2001).

Table 3 Average daily values for the pollution indicators in the receiving water (ONA, 2009).

Numerical rating

Verbal judgments of preferences

Pollution indicators

Unit

Value

1 3 5 7 9

Equal preference Moderate preference Strong preference Very strong preference Absolute preference

Dissolved oxygen (O2) Chemical Oxygen Demand (COD) Nitrate (NO3) Nitrite (NO2) Total Kjeldahl Nitrogen (TKN) Ammonium (NH4) Phosphate (PO4) Total phosphorous (Pt) Total Suspended Solids (TSS) Temperature (T ) pH Phenol index (C6H5OH) Mineral oils Foam Fecal streptococci (FS) Total coliform bacteria (T-coli) Escherichia coli (E. coli) Dry residue Sodium (Na) Chlorine (Cl) Sulfate (SO4) Arsenic (As) Zinc (Zn) Copper (Cu) Lead (Pb) Chromium (Cr) Nickel (Ni) Mercury (Hg) Cadmium (Cd)

mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l C e mg/l mg/l mg/l U/100 ml U/100 ml U/100 ml mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l

5.33 123.12 46.18 0.48 24.36 6.3 0.5 6.2 4363.67 28 6.9 0.016 0.58 0.63 4941 13,738 11,437 2238.4 296.6 337.67 364.27 32.1 4866.23 1173.21 69.67 36.93 403.05 0.933 3.625

Generally speaking, the values for aij are identified using questionnaires filled out by representatives of the stakeholders involved. In this case study, given the manager’s lack of knowledge regarding priority indicators and criteria, we have evaluated the values for aij ourselves. The matrix is then completed as follows: ajj ¼ 1 and aji ¼ 1/aij (reciprocal value). 4) To calculate the relative importance (weight) of each criterion with regard to its contribution to the objective. The procedure is as follows: The values in each column are summed; Each element in the matrix is divided by the sum of its column (normalization); The average for each element in a row of the matrix is calculated. The averages represent the weight vector (eigenvector). 5) To check the degree of consistency between the preferences. The consistency index (CI) is determined with the following formula using eigenvalue lmax:

4. Results and discussion

CI ¼ ðlmax nÞ=ðn 1Þ

(2) An example is presented in this paper to evaluate the objective “Do not alter water quality of receiving water”. This objective is assessed by integrating six associated criteria, four of which concern water usage (Fig. 1):

where: n: Matrix size. Consistency can be checked using the consistency ratio CR

CR ¼ CI=RI

(3)

where: RI: Random Index shown in Table 2. If CR < 0.10, the assignment of judgments is acceptable, if not the procedure should be reviewed (Al-Harbi, 2001).

Overall chemical quality; Suitability for use for drinking water production; Suitability for use for irrigation; Suitability for use for fishing; Suitability for use for swimming; State of eutrophication.

3. Case study We applied this methodology to the UDS in Jijel, Algeria. Jijel is located on the north-eastern coast of Algeria. It covers a surface area of 6238 ha and has 135,000 inhabitants. The city is equipped with a public drainage network which services 94% of the population. The rest of the city is serviced by private systems. Of the total public drainage network 92% is a combined network and 8% is a separate network. The total length of the network is around 113 km. The capacity of the WWTP (wastewater treatment plant) is 30,000 m3/day or 150,000 population equivalent (ONA, 2009). A significant proportion of the network (around 25%) is not connected to the WWTP. The average dry weather flow for the WWTP is approximately 9400 m3/day. The volume of sanitary sewage (untreated) directly discharged into the environment in dry weather is around 3000 m3/day.

The assessment of these different criteria depends on several indicators. As previously stated, only the indicators actually available on the study site are taken into account. In this case study measurements of the water’s pollution indicators are available (Table 3). These measurements are used to assess indicator performance. The representativeness of the data needs to be validated. Firstly, the pollution indicators are not sufficiently stringent. The European Union’s Water Framework Directive (EC, 2000) identified 33 pollutants as priority targets for environmental quality standards regarding to the chemical quality of bodies of water. Secondly, the measurements were collected over one single sampling campaign carried out in June 2008. Furthermore, there is no detailed information on the conditions in which the samples were taken. It is important that the reliability of the

Table 2 Random Index (RI) values (Al-Harbi, 2001). Matrix size

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

RI

0.00

0.00

0.58

0.90

1.12

1.24

1.32

1.41

1.45

1.49

1.51

1.53

1.56

1.57

1.59


51

Fig. 3. Performance of indicators for criteria C1eC6.

data is established prior to implementing the methodology in order to ensure its effectiveness. However, due to the lack of data, the data actually available has been used to explain the methodology. The performance functions established are used to convert concentration values into scores between 0 and 1 (see Fig. 2). This operation assigns a score to each indicator (Fig. 3). For the pairwise comparison phase the degree of toxicity of the parameters is taken into account. The performance indicator scores are aggregated using Eq. (1) with corresponding weight values (Fig. 4). The judgments of preference assigned to the criteria matrices and the

studied objective matrices are acceptable as their consistency ratios are less than 0.1 (Table 4). As can be seen in Fig. 5, the criterion C3 shows good performance (PC3 ¼ 0.719), while all the other criteria show relatively poor performances (PC1 ¼ 0.427; PC2 ¼ 0.294; PC6 ¼ 0.229; PC4 ¼ 0.220 and PC5 ¼ 0.159). As a result, the overall performance score for objective O1 is quite low: PO1 ¼ 0.357. Therefore, ONA managers should undertake measures to improve the water quality of the receiving water. For example, they could start to reduce the discharged pollutant load and increase the proportion of the wastewater network connected to WWTP.

Fig. 4. Weighted hierarchy for the studied objective.

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Table 4 Consistency ratios for the selected matrices. Criteria C1 Matrix size (n) Eigenvalue (lmax) Consistency Index (CI) Consistency Ratio (CR)

C2

Objective C3

C4

7 15 11 11 7.255 15.540 11.658 11.268 0.042 0.039 0.066 0.027 0.032 0.025 0.044 0.018

C5

C6

O1

6 6.273 0.055 0.044

6 6.198 0.040 0.032

6 6.344 0.069 0.055

Fig. 5. Performance of criteria for objective O1.

5. Conclusion and further research This paper presents a methodology developed to support sustainable UDS management. The themes, objectives and criteria developed are well adapted to local specificities including the difficulty in acquiring precise data on the drainage network, pollution in the discharge environment and the risk of waterborne diseases etc. It is particularly focused on making the best use of existing infrastructure. The methodology employs a structured approach to draw up and implement indicators, criteria and objectives. A top-down descriptive approach (from objectives to criteria to indicators) is developed in order to facilitate the definition of themes related to UDS sustainability, priority objectives for the managers, and appropriate criteria. A bottom-up approach is then used to produce a performance score for element of each level. The methodology has been applied to a real case study in Algeria. The results provide interesting information that is useful to the Algerian UDS managers. It provides a set of indicators which are important for operational applications. It also identifies the objectives requiring improvement and the criteria and indicators responsible for this. This therefore allows managers to focus studies in order to understand the main reasons for the quality failures observed. However, the method developed has only been validated in principle. The differences between the methodologies used in the literature and in our case study have not been compared. Clearly feedback from the different UDS stakeholders is needed to back up the results obtained from this method. This work will be done in a future study when more data becomes available. References Al-Harbi, K.M.Al-S., 2001. Application of the AHP in project management. International Journal of Project Management 19, 19e27. Ashley, R., Blackwood, D., Butler, D., Jowitt, P., Davies, J., Smith, H., Gilmour, D., Oltean-Dumbrava, C., March 2008. Decision support for sustainable option selection in integrated urban water management. ASCE Journal of Environmental Engineering 134, 200e209. Babut, M., Bonnet, C., Bray, M., Flammarion, P., Garric, J., Golaszewski, G., October 2003. Developing environmental quality standards for various pesticides and priority pollutants for French freshwaters. Journal of Environmental Management 69 (2), 139e147.

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