Water Reclamation and Reuse in Costa Brava ( ): Lessons learned and practical contributions

Transcription

1 Water Reclamation and Reuse in Costa Brava ( ): Lessons learned and practical contributions Lluís Sala Workshop INNOVA-MED CONFERENCE Innovative processes and practices for wastewater treatment and re-use in the Mediterranean region Girona, 8-9 October 2009

2 The Costa Brava Name given to the coastal strip of the Girona province, in NE Spain Mediterranean climate: hot, dry summers, mild winters and usually wet autumns and springs (avg. rainfall around 650 mm/year) Rugged coastline, with beautiful beaches, tourism-oriented area 27 municipalities, approx. 100 km from north to south (straight line) Resident population, approx. 240,000 inhabitants. Maximum population in summer estimated at over 1 million inhabitants (Spanish, European)

3 The Consorci de la Costa Brava (I) Water agency created in 1971 by the 27 municipalities of the coastal area of Girona s province. Deals with the whole water cycle: Wholesale purveyor of drinking water to 14 municipalities (3 of them external to CCB) 18 million m 3 /year in 2008 Biological wastewater treatment to 28 municipalities (2 of them external to CCB) in 18 WWTP 31 million m 3 /year in The 2 remaining municipalities to be connected to WWTP by Reclamation and reuse of treated wastewater for nonpotable purposes since million m 3 /year in 2008 produced in 14 facilities Construction, operation and maintenance of water treatment facilities funded by the Catalan Water Agency (regional water authority, tax collecting agency)

4 The Consorci de la Costa Brava (II) Facilities operated by CCB (as of 2009)

5 The Consorci de la Costa Brava (III) Volumes treated and reclaimed (2008) Operational area Number of WWTP Volume of wastewater treated in 2008, million m 3 /year Number of reclamation facilities Volume of reclaimed water produced in 2008, million m 3 /year Percentage of water reclamation, % Northern Central I Central II Southern Total

6 The Empresa Mixta d Aigües de la Costa Brava, SA -Costa Brava Water- Created on April 1st, 2006 Shareholders: Public: Consorci de la Costa Brava (33 %) Private: Grouping of Economic Interest (67 %), originally formed by the following companies: SEARSA, SOREA and AQUALIA. Operates all the wastewater treatment and reclamation facilities owned by the CCB and some owned by the municipalities served by the CCB (i.e., pumping stations)

7 Evolution of reclaimed water production

8 Breakdown of uses Aquifer recharge 34% Golf course and landscape irrigation 19% Agricultural irrigation 12% Internal and nonpotable urban uses 3% Environmental uses 32% 2008 Golf course and landscape irrigation Environmental uses Aquifer recharge Agricultural irrigation Internal and non-potable urban uses

9 Reasons to reuse Over-extraction, depletion and pollution of the small coastal aquifers (mid 60 s). Increase in non-potable urban demand (golf courses, private and municipal gardens) (late 80 s mid 90 s). Significant investment for an adequate supply of drinking water (water transfers and desalination) (late 80 s to early 00 s). Significant investment in wastewater collection and treatment to biological, secondary level (mid 70 s to present day). Effluent discharged into the sea through submarine outfalls was the common practice = a valuable resource was lost. An additional treatment (reclamation) produces safe water to cope with non-potable demands = more logical resources management in the area, specially in dry periods. There are better things to do with the treated effluent rather than discharge those valuable resources into the sea!

10 Water reuse in the Costa Brava

11 Key developments / achievements (I) Practical criteria for the use of reclaimed water in golf course irrigation ( ) Management of water of changing quality Nutrient recycling is also a benefit: nutrient contributions have to be accounted and fertilization plans modified accordingly Factors affecting nutrient contributions: Nitrogen and phosphorus: Type of WWTP Storage of reclaimed water N/P ratio in water decreases with increased HRT Potassium Salinity of drinking water Discharges to sewer lines

12 Key developments / achievements (II) Energy balances in the municipal water cycle ( ) Ecological footprint of the different parts of the water cycle Water reclamation and reuse leads to energy savings where drinking water requires high energy consumption: Surface water transported to large distances and/or high altitudes Groundwater transported to large distances and/or high altitudes Desalinated, in any of the distribution situations New criteria to decide where to promote water recycling step towards a greater sustainability Advantages: Tool for a totally objective assessment Independent of prices, taxes and subsidies Applicable to any given technology Universal

13 Key developments / achievements (II) Energy balances in the municipal water cycle ( ) ENERGY CONSUMPTION OF WATER SOURCES IN TOSSA DE MAR, COSTA BRAVA 6,00 Consumption, kwh/m3 5,00 4,00 3,00 2,00 1,00 0,00 Groundwater (Tordera wells in Blanes) Groundwater (local wells) Desalination (in Blanes) Reclaimed water (Title-22) Kind of water Withdrawal Treatment Transportation

14 Key developments / achievements (III) Publication of key paper Towards sustainability in water recycling by L. Sala and M. Serra. Water Science and Technology Vol 50 No 2 pp 1 7, IWA Publishing 2004, originally presented at the IWA 4th International Symposium on Wastewater Reclamation, Recycling and Reuse, Mexico DF, November 2003 Water reuse as a tool for efficient allocation of water resources Ecological analysis of the cycle of the main pollutants (carbon,nitrogen, phosphorus) Public health protection Energy balances in the municipal water cycle Determination of the positive externalities

15 Key developments / achievements (IV) Development of scientific information and technical criteria forthe combined use of disinfecting agents in water reclamation = wide range disinfection, better public health protection ( , experiments by UB + UPC + EMACBSA+ CCB in Castell d Aro and Blanes reclamation plants) Indicator microorganisms Escherichia coli Clostridium spores Somatic coliphages 5 5, , , , ,0 1 95% IC 0-1 N = 12 FILEC UVEC 1UV2CLEC 0,6CLEC 1UVEC 1UV1CLEC 2UV1CLEC 95% IC 0,0-1,0 N = FILCSR 2UVCSR 1UV2CLCSR 0,6CLCSR 1UVCSR 1UV1CLCSR 2UV1CLCSR 95% IC 0-1 N = FILSOM 2UVSOM 1UV2CLSOM 0,6CLSOM 1UVSOM 1UV1CLSOM 2UV1CLSOM Similar results with pathogens: infective oocysts of Cryptosporidiumspp. and enteroviruses not detectable in 100 litre-samples when combination of UV + chlorine was used

16 Key developments / achievements (V) Improvement of disinfection capabilities and public health protection EVOLUTION OF THE RECLAIMED WATER QUALITY IN TOSSA DE MAR. PERCENTILE 90 OF THE ANNUAL SET OF DATA. SS, turbidity 25,0 20,0 15,0 10,0 5,0 Until 2006, faecal coliforms Annual number of samples SS: values Turbidity: values FC or Escherichia coli: values Escherichia coli 0, Year SS, mg/l Turbidity, NTU Escherichia coli, cfu/100 ml 1

17 Key developments / achievements (V) Improvement of disinfection capabilities and public health protection EVOLUTION OF THE MONTHLY AVERAGE VALUES OF MICROBIAL INACTIVATIONS IN THE TOSSA DE MAR RECLAMATION PLANT 7,0 6,0 Inactivation, log units 5,0 4,0 3,0 2,0 1,0 0,0-1,0-2,0-3,0 G03 A03 J03 O03 G04 A04 J04 O04 G05 A05 J05 O05 G06 A06 J06 O06 G07 A07 J07 O07 G08 A08 J08 O08 G09 A09 J09 Coliformes fecals MONTHS E. coli (FC until 2006) SRC Lineal (E. coli (FC until 2006)) Lineal (SRC)

18 Key developments / achievements (VI) Reclaimed water distributed through specific networks does not increase the risk of Legionelladisease compared to the use of drinking water GLOBAL RISK INDEX OF LEGIONELLA DISEASE ACCORDING TO THE EVALUATION GUIDE BY THE SPANISH HEALTH MINISTERY 100 Acute risk Value of the index Moderate 0 Tossa distribution system - 1 Tossa sprinkler Lloret storage tank - 2 Sampling point Lloret sprinkler TAB < 100,000 cfu/ml and without biolfilm TAB > 100,000 ufc/ml and with biofilm plus fouling

19 Key developments / achievements (VII) Applicability of the measurement of redox potential for the online control of chemical disinfection (2007-?) From Lucena & Muñoz (2009) -

20 Key developments / achievements (VIII) Collaboration on pioneer studies on Waterharmonica systems -mostly, but not exclusively, constructed wetlands which are used for water treatment but that also have a clear nature enhancement purpose (Waternet, Vrije Univ. Amsterdam) Discharge from WWTP: particles, flocs, loose bacteria, nutrients, low dissolved oxygen A portion of the river is impaired Waterharmonica Discharge from Waterharmonica systems: algae, rotifera, cladocera, copepoda, lower nutrients, higher dissolved oxygen What is discharged is much closer to the biota living in the river ecosystem Can help comply with the EU Water Framework Directive!!

21 Key developments / achievements (IX) Pioneer studies on biological filtration by cladocera cultures as natural reclamation treatment Dutch-Catalan cooperation project (2007 -?)

22 Key developments / achievements (X) Development of reclaimed water networks in some municipalities of the Costa Brava where drinking water is scarce and/or expensive Initially, only for municipal non-potable uses. Will to extend the supply to private non-potable uses In operation in Tossa de Mar and Lloret de Mar (both since May 2007) and in construction in Port de la Selva In Tossa de Mar and Lloret de Mar produce water and energy savings Detailed monitoring has shown no quality problems Reclaimed water supplied to municipalities for their own non-potable urban uses may be subject to pricing in the near future.

23 Since 2007: Applied research Cooperation with universities to: Promote applied works of Master s students Help with ongoing studies (i.e., MODELKEY project, Models for assessing and forecasting the impact of environmental key pollutants on marineand freshwater ecosystems and biodiversity ) Answer practical questions, i.e Do faecal microorganisms inactivated during disinfection regrow on reclaimed water storage facilities or theones found are from external contributions? Build or host pilot plants and learn from experience: Biological filtration at Empuriabrava MF + RO at Torroella de Montgrí coupled to the MODELKEY project MBR at Castell-Platja d Aro LEQUIA group, UdG

24 Some recent work 6th Conference on Wastewater Reclamation and Reuse for Sustainability, October 9-12, 2007, Antwerp, Belgium L. Sala, A. Angelakis and V. Lazarova: Good practice examples in Southern Europe. Workshop: European experience and priorities: The initiative of the EU-MED Water Directors. Antwerp, Belgium, 9 October 2007 G. Borràs, M. Soler and L. Sala:Summary of data concerning the quality of the reclaimed water produced at the Blanes Reclamation Plant (Costa Brava, Girona, Catalonia). L. Sala and S. Romero de Tejada:Use of reclaimed water in the recreation and restoration of aquatic ecosystems: practical experience in the Costa Brava region (Girona, Spain). M. Montemayor, A. Costan, F. Lucena, J. Jofre, J. Muñoz, E. Dalmau, R. Mujeriego and L. Sala:The combined performance of UV light and chlorine during reclaimed water disinfection Presentació[1.3Mb] A. Costan, M. Montemayor, F. Lucena, J. Jofre, J. Muñoz, S. Quintana and L. Sala:Microbiological water quality improvement from reclaimed water discharges into Ridaura River (Costa Brava, Girona, Spain) Presentació[8.6Mb] J. Muñoz and L. Sala:Environmental criteria for alternative nutrient removal in treated wastewater. (Best poster award of the conference) R.Kampf, L.Sala, H. Van der Geest, A.Romani, J.Comas, T.Claassen, S.Gerbens, R.Neef, W.Menkveld:Biological filtration of treated wastewater by Daphnia: An alternative for techincal filtration, or an addition? L.Sala, T.Claassen, R.Kampf, J.Sala, D.Boix, H.Van der Geest:Trophic webs from discharges: Nature enhancement through the waterharmonica concept

25 RO water produced from Torroella de Montgrí s secondary effluent and used for the EU MODELKEY project Thank you for your attention! Questions?