The water-energy nexus: A sustainability assessment of water supply in Costa Brava, Spain Jun 02, 2014

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1 Chelsea Burns, American University, United States Water treatment plant, Costa Brava, Spain. The Cost a Brav a in Nort heas tern Medi terr ane an regi on of Cata luny a, Spai n is a hots pot for touri sm duri Global Water Forum 1

2 ng sum mer mon ths. Pop ulati on incr ease s from 240, 000 to over 1 milli on bet wee n June and Aug ust. For Toss a de Mar Global Water Forum 2

3 and Llor et de Mar, two of mos t visit ed mun icipa lities alon g Cost a Brav a, local wat er reso urce s hav e prov Global Water Forum 3

4 en insu fficie nt duri ng pea k seas on sinc e 197 0s. In last deca de, issu es of saltwat er intru sion due to Global Water Forum 4

5 over expl oitat ion of Tord era aqui fer duri ng sum mer mon ths has forc ed auth oriti es to dev elop o r supp ly alter Global Water Forum 5

6 nati ves, such as desa linat ion and wat er reus e. Energy intensity of supply alternatives In a recent study, we analyzed entire water life cycle of extraction, treatment, and conveyance to end users in Tossa de Mar and Lloret de Mar from Although desalination can guarantee a supply source in times of drought, energy intensity of this alternative makes it an expensive alternative, and in a part of world beset by economic challenges, an inherently unsustainable supply alternative. Water authorities in Catalunya are consequently forced to limit deployment and this restriction significantly compromises overall utility of desalination. 2 As water availability is predicted to become more variable in future due to climate change, authorities need to question viability of this supply alternative, whose sustainability is subject to economic shocks. Regarding individual energy components of water life cycle, analyzing energy intensity of conveyance proves a relevant exercise. For example, desalinated water must first be conveyed from treatment plant in Blanes to treatment plant in Tordera and n later transferred to municipalities. In comparison, tertiary treated water, an advanced wastewater treatment process that improves effluent quality beyond traditional sewage Global Water Forum 6

7 treatment process, is treated and conveyed within municipal boundaries. In Tossa de Mar, when treatment costs are included, total energy cost for tertiary treatment was 0.79 kwh/m 3 versus 3.69 kwh/m 3, for desalination. Therefore, it is less energy intensive in treatment and conveyance costs to augment supply through tertiary treatment than through desalination. Or sustainability considerations Although water reuse presents some advantages over desalination, it involves limitations as well. Water reuse is currently only available for non-potable applications throughout Costa Brava, meaning it is not treated to drinking water standards. Treating reclaimed water to meet potable standards is also energy intensive. Furrmore, additional infrastructure, such as new pipeline networks and depositories, are required for conveyance and maximized efficiency. Budget constraints challenge overall sustainability of this supply alternative. Need for sectoral integration In Spain, water policy is managed in a variety of ways from national to municipal level. Energy policy, on or hand, is primarily regulated at national level. The complexity of political and institutional structures behind water supply and energy policy makes sectoral integration difficult. The decision-making process is multidimensional: supranational, national, and local policies influence overall management scheme. Therefore, policies passed within entire institutional web have direct impacts on local municipal supply. Currently, representation from energy sector only resides in one leg of decisionmaking process. The National Water Council advises Ministry of Environment on how national water plans, agricultural, energy, industrial, or land-use plans impact water resources. 3 The head of Directorate General for Energy Policy and Mines, Ministry of Global Water Forum 7

8 Industry, Tourism and Commerce, as well as a representative from Spanish Association of Electrical Industry, advise national water policy makers. 4 According to a source at Catalan Water Agency, se members of energy sector sit within council to ensure that ir electricity production interests are satisfied. They do not offer advice on how water sector can better incorporate energy planning. This absence of integration means regional and local water authorities never come into contact with national energy planners, and thus, water supply decisions are made independent of energy sector. 5 This is insufficient and inefficient. It is critical that energy consumption remains a parallel concern under each subset of overall decision-making framework for water planning. Discussion Water authorities face specific energy intensity and sustainability challenges. These variables must be accounted for in all future water management plans. For example, water reuse has potential to redirect pressure from local aquifers to tertiary wastewater treatment, but certain limitations impede sustainability of supply mechanism. If conveyance and treatment values are compared, it is clear that furr development of tertiary treatment facilities in Tossa de Mar and Lloret de Mar would be a superior option to desalinated water if an equivalent volume of drinking water could be replaced. However, keeping limitations of tertiary supply in mind is critical. Applying reverse osmosis to tertiary treated water to bring it up to drinking water standards results in increased energy consumption. Thus far it is unclear if this method is comparable to desalination. At a global level, it is critical to remain aware of future projections of water supply alternatives that could shift overall energy consumption. Between 2006 and 2011 global desalination production increased from 25 million m 3 to 72 million m 3 per day. By 2015, projection stands at 100 million m 3. 6 In Spain, 2005 National Hydrological Plan under A.G.U.A program promotes increased construction of desalination and water reuse treatment facilities. Catalunya s regional water management plan follows a similar trend. While se supply alternatives meet increasing demand for fresh water resources, y are associated Global Water Forum 8

9 with increasing energy costs. Although desalination has potential to maintain healthy aquifer levels and avoid additional pipeline construction over hundreds of miles, it results in high energy costs and creates a greater demand for energy producing natural resources. Detailed energy-for-water production data is important for policy makers to integrate energy considerations at each institutional level throughout entire water resource management hierarchy. References: Burns, C. (2013), Important Water-Energy Nexus Considerations: A Sustainability Assessment of Water Supply in Two Municipalities of Costa Brava. Consorci Costa Brava. Girona. Spain. exus%20report.pdf Pers. comm. Agencia Catalana del Agua, 2013 Varela Ortega, C. & Hernández-Mora, N. (2010), Institutions and Institutional Reform in Spanish Water Sector: A Historical Perspective, in A. Garrido & M. Ramón Llamas (Eds.), Water Policy in Spain (p ). Leiden: CRC Press. OECD (2012), Meeting water coherence challenge, in OECD, Meeting Water Reform Challenge, OECD Publishing, Paris. doi: / en Pers. comm. Agencia Catalana del Agua, 2013 Olsson, G. (2012), Water and Energy: Threats and Opportunities. London, UK: WA Publishing. In August 2013, Chelsea graduated with dual masters degrees in International Relations and Natural Resources and Sustainable Development from American University in Washington. D.C. and University for Peace in Costa Rica. Currently, Chelsea works as a consultant for a Smart Grid Technology company. She conducts market research regarding conservation technologies and regional water/energy nexus initiatives in order to assess how water agency programs might benefit from Advanced Metering Technologies (AMI) and community Global Water Forum 9

10 outreach programs. This article summarizes Important Water-Energy Nexus Considerations: A Sustainability Assessment of Water Supply in Two Municipalities of Costa Brava, a water-energy nexus analysis of two coastal tourist destinations in Norrn Catalunya. The goal of report was to evaluate fluctuation of water supply across year and to examine relative energy costs of each of major sources used to meet water demand. Extraction, treatment, and distribution data sets for volume (m3) and energy consumption (kwh) were compiled monthly between years 2007 and 2011 for each water supply source. From se data, ratios (kwh/m3) were calculated to determine specific and relative energy consumptions. For full text see published version on Catalan municipal wholesale water supplier, Consorci Costa Brava s, website. The views expressed in this article belong to individual authors and do not represent views of Global Water Forum, UNESCO Chair in Water Economics and Transboundary Water Governance, UNESCO, Australian National University, or any of institutions to which authors are associated. Please see Global Water Forum terms and conditions here. Global Water Forum 10