Good practice examples in Southern Europe

Transcription

1 Good practice examples in Southern Europe L. Sala, A. Angelakis and V. Lazarova Workshop: European experience and priorities. The initiative of the EU-MED Water Directors Antwerp, Belgium, 9 October 2007 Fantasy, fashion or necessity? Is water reuse a fantasy? No! Increase in water reuse projects implemented worldwide, specially in dry areas Is water reuse a fashion? No! Projects on operation get improved, not abandoned. Is water reuse a necessity? Gabriel Borràs (Head of the Planning Area, Catalan Water Agency, NE Spain): Water reuse has an essential role in our water resource management. Used water, when treated, is not a waste product but an essential water resource Ramon Folch (Chair of Polytechnic University of Catalonia's Social Council and Professor of the UNESCO Chair for Sustainable Development): If wastewater treatment plants would turn into reclamation plants we would have reclaimed water, pure and clear. We should think about it. After all, the bottled water we drink is reclaimed water too. By the natural cycle, but reclaimed. If we already do desalination, why don t we do reclamation, which is easier? (Excerpt from the article Aigua llençada ( Wasted water ), on El Periódico de Catalunya, 8th July 2007). 1

2 Why reuse in Southern Europe? Greater overall water demands per capita -agricultural irrigation included- than in Northern Europe Huge increase in population: tourism and immigration Irregular rainfall patterns and exposure to frequent droughts Need to comply with the WFD, a challenging task in such an environment Photos by courtesy of Consorci de la Costa Brava EU Water Framework Directive The environmental value of water Environmental value Agricultural and recreational value Questions: Where has water the highest environmental value? What kind of water is best to be used for irrigation? Photos by courtesy of Consorci de la Costa Brava 2

3 Change of paradigm Treat and dispose is obsolete Develop new resources with the least environmental impact Limitation in water transfers (as a general rule) Limitation of desalination plants (energy) Water recycling: give water a second chance All the water used for urban supply is concentrated in one facility (useful volumes) Most treatment before reuse is already provided by biological secondary treatment To get the water out the waste Photo by courtesy of Consorci de la Costa Brava Why reclaimed water? (I) A great portion of the overall water demand is for non-potable uses Okun (1998): only about 15% of water used in urban areas (of US) is required to be of potable quality It is a local resource: water is already in the vicinity of where it has to be used It is an auxiliary resource: it can save precious drinking water or water with environmental functions Photo by courtesy of Consorci de la Costa Brava Graphic by courtesy of Dr. Valentina Lazarova 3

4 Why reclaimed water? (II) Where traditional resources have been fully used, reclaimed water may be the new resource with the least marginal cost Safe water can be produced at reasonable costs Under certain circumstances, concomitant energy savings can be achieved (lower CO 2 emissions, climate change) Consumption, kwh/m3 6,00 5,00 4,00 3,00 2,00 1,00 ENERGY CONSUMPTION OF WATER SOURCES IN TOSSA DE MAR, COSTA BRAVA 0,00 Groundwater (Tordera Groundwater (local Desalination (in wells in Blanes) wells) Blanes) Kind of water Reclaimed water (Title-22) Withdrawal Treatment Transportation Graphics by courtesy of Consorci de la Costa Brava The role of reclamation After urban use, water quality can be restored to a great extent, so it can be beneficially reused again instead of discharged Reclamation is a water resource generation activity, not an extension of the wastewater treatment Similar function to a reservoir, an aquifer or a desalination plant to produce water, even though purpose is not drinking water supply Reclamation makes wastewater treatment plants work better Photo by courtesy of Consorci de la Costa Brava 4

5 How is public health protected? Wide range disinfection can be performed by various technologies and/or by the combination of more than one disinfectant agent. Proven results with ozone, UV, UV + chlorine. Greater removal of microorganisms and more diversity targeted (bacteria, viruses, Cryptosporidium) THM concentrations below drinking water levels if chlorination is managed with care On-line probes (turbidity, residual chlorine) for reliability of operation of water reclamation plants water not fulfilling quality requirements shall not leave the facility Photos by courtesy of Consorci de la Costa Brava Photo by courtesy of Prof. Francisco Lucena The growing need for indirect potable reuse (I) Traditional practices of water resources management usually, very sustainable- have been destabilized by development (i.e., Greek islands, Mediterranean Spanish coastline, etc.) New practices are needed to return to a more sustainable management => wastewater reclamation and reuse as one of the important tools and indirect potable reuse as a likely option for the future 5

6 The growing need for indirect potable reuse (II) Main advantages: No distribution facilities needed (lower investment costs) Whole year operation, not just in a particular season (i.e., as happens with irrigation) Residence time in aquifer and dilution with natural water improve quality; identity is lost Much better option than the traditional and surprisingly well accepted!!- indirect potable reuse due to the discharge of secondary effluents, runoffs and urban stormwaters to rivers and streams Unplanned indirect potable reuse: discharge of secondary effluent, usually non-disinfected treated wastewater. Graphic by courtesy of Dr. Andreas Angelakis. Planned aquifer recharge: discharge of disinfected, aditionally treated wastewater. Photo by courtesy of Consorci de la Costa Brava. Agricultural irrigation Vitoria, Spain: Since 1996, Title-22 treatment for 35,000 m 3 /day to be used for high value crops, some to be eaten raw and exported abroad. No adverse health effects reported. Increase in farmers standard of living => from dry farming (EU subsidies) to modernized agriculture (business mentality). 7,000,000 m3 reservoir only for the storage of winter reclaimed water already constructed. Photos by courtesy of TYTSA, Vitoria 6

7 Agricultural irrigation Noirmoutier, France: Tertiary treatment by lagooning for 6,100 m 3 /day. Irrigation of 500 ha of high value crops (potatoes) and protection of shellfish areas. Demand of farmers for the reuse of 100% of wastewater. Clermont-Ferrand, France: Tertiary treatment by lagooning for 10,000 m3/day. Irrigation of 700 ha of corn. First EU epidemiological study: no adverse health effects (aerosols, quality in distribution network). Photos by courtesy of Dr. Valentina Lazarova Agricultural irrigation San Rocco, Milano, Italy: Reclamation plant (filtration + UV disinfection) with a treatment capacity of 1 million p.e. (4 m 3 /s). Quality criteria: <10 E. coli / 100 ml. Irrigation of 22,000 ha of high value crops, including some to be eaten raw. Photos by courtesy of Dr. Valentina Lazarova 7

8 Agricultural irrigation Thessaloniki, Greece: Since 2006, 175,000 m 3 /day of secondary effluent are mixed (1:5 ratio) with water from the Axios river and used to irrigate 2,500 ha in the Halastra-Kalohori area. Projects for the reuse of up to 320,000 m 3 /day throughout Greece. RiverAxios industrial WWTP Sindos Diversion station 1 irrigation channel Diversion station 2 Sewer pipeline to river Axios Chalastra-Sindos agricultural area West Pumping Station shellfisheries Thessaloniki WWTP Thessaloniki main sewerage pipeline Thessaloniki Gulf East Pumping Station outfall pipeline Scheme from Soupilas A. and Papastergiou F. (2002). Preparations for large scale reuse of treated domestic wastewater for irrigation purposes in Thesaloniki. In: Proc. of Regional Symposium on Water Recycling in Mediterranean Region, Iraklio, Greece, September, pp Photos by courtesy of Mr. Athanasios Soupilas Golf course irrigation Costa del Sol, Málaga, Spain: 6 reclamation plants on operation. Peak production of 66,000 m 3 /day of disinfected effluents supplied to 34 golf courses (= 7.0 million m 3 /year). Future: 21 existing golf courses to be retrofitted with reclaimed water, expected need estimated at 24 million m 3 /year. Graphic by courtesy of ACOSOL, SA Source: 8

9 Landscape irrigation and urban non-potable uses Madrid, Spain: 2.14 m 3 /s of reclaimed water (Title-22 treatment train, Turbidity < 1.5 NTU, FC < 20 cfu/100 ml) to be reused for the irrigation of 17 urban parks (3700 ha) through 108 km of pipelines. Capital costs: 145 million. Potable water savings, 22.7 million m 3 /year. Partially in operation: 4.26 million m 3 /year supplied through the Red Centro (Central Network) to irrigate 637 ha of parks and landscaped areas. Graphics by courtesy of Ayuntamiento de Madrid Environmental reuse (funded with EU Cohesion Funds) Empuriabrava, Costa Brava, Spain: Since 1998, approx. 650,000 m 3 /year of nitrified and partially denitrified effluent is further polished in a 7 ha constructed wetland. Reclaimed water is used at the Aiguamolls de l'empordà Natural Park to recreate wetlands and restore vanishing wet meadows, an ecosystem of high value and that has suffered a steady decline in the area since the 60 s. Photos by courtesy of Consorci de la Costa Brava 9

10 Industrial reuse Prato, Tuscany, Italy: Lack of water resources has prompted the development of reuse in the local textile industries. Since summer 1998, they use reclaimed water (ozonation, contact filtration and biological carbon adsorption) mixed with the treated water derived from the Bisenzio river, whereas an equal flow of treated and disinfected wastewater from the Prato- Baciacavallo WWTP is diverted to the Bisenzio river to maintain its water balance. First example in Italy of integrated water management including water reuse. Information by courtesy of Prof. Costantino Nurizzo Aquifer recharge Blanes, Costa Brava, Spain: Since 2003, approx. 3.0 million m 3 /year of denitrified, Title-22 reclaimed water are used for the recharge of the lower Tordera aquifer. Part of a larger plan designed by Catalan Water Agency to improve the condition of the lower Tordera aquifer that includes desalination for a portion of domestic supply (in operation since 2002) and promotion of internal recycling in the local industries. Photos by courtesy of Consorci de la Costa Brava 10

11 Aquifer recharge, agricultural irrigation and environmental reuse Baix Llobregat, Barcelona, Spain: 30 million m 3 /year project for the delivery of high quality reclaimed water for several uses in the Baix Llobregat area, south of Barcelona. In operation since summer 2006, already 9.7 million m 3 of reclaimed water, formerly wastewater discharged into the sea, have been used for streamflow augmentation in the Llobregat river, and 0.4 million m 3 for seawater intrusion control. Photos by courtesy of the Catalan Water Agency Conclusions (I) Given the future challenges in Southern Europe (demand growth, EU WFD, impact of climate change), a rational and accurate management of water resources is needed. Treated wastewater offers an opportunity to develop a new resource to safely cope with non-potable demands and/or to improve the management of the overall water cycle. Public health protection is strictly observed and is an essential part of water reuse projects. Santa Clotilde Gardens, Lloret de Mar, Costa Brava, Spain, irrigated with reclaimed water since May Photo by courtesy of Consorci de la Costa Brava. 11

12 Conclusions (II) Practical experience on reclamation and reuse is available in Southern Europe for a great variety of uses which improve the situation of water resources, from local to regional level. Increasing trend in the development of water reuse projects in all the Mediterranean countries A sound policy is needed to help them succeed, since they can improve people s standard of living and the quality of their local environment. Tossa Creek, Tossa de Mar, Costa Brava, Spain, streamflow augmentation with reclaimed water for ecological purposes, June Photo by courtesy of Consorci de la Costa Brava. Thank you for your attention Questions? 12