Case Study Report Serpis
SERPIS RIVER (Jucar River Basin District), Spain
(Deliverable D33)
Author
Date
G. Lozano, M. Pulido, J. Andreu
April 15, 2007
Contact information AquaMoney Partners
Colophone
This report is part of the EU funded project AquaMoney, Development and Testing of Practical Guidelines
for the Assessment of Environmental and Resource Costs and Benefits in the WFD, Contract no SSPI022723.
General
Deliverable
Deadline
Complete reference
Status
Approved / Released
Reviewed by
Pending for Review
D33. Case study Report Jucar RBD (Serpis river basin)
15-04-2007
Lozano, G., Pulido, M., J. Andreu (2007), Case study Report Jucar, Subcatchment
Serpis UPVLC, Valencia, Spain
Author(s)
Date
Comments
Second draft
First draft for
Lozano, G., M. Pulido, 15-04Comments
J. Andreu
2007
Under Preparation
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Restricted to other programme participants (including the Commission Service)
Restricted to a group specified by the consortium (including the Advisory Board)
Confidential, only for members of the consortium
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Date
X
Copyright © 2006
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any
means, electronic, mechanical, photocopying, recording or otherwise without the prior written permission of the copyright holder.
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Content
1. General case study characteristics
1.1 Location of the case study area
1.2 Geographical characteristics
1.2.1 Physical general characteristics
1.2.2 Climate
1.2.3 Lithology & Geology
1.2.4 Population and land uses
1.2.5 Biotic framework
1.3 Water system characteristics
1.3.1 Total natural runoff and available water resources
1.3.2 Streams and aquifer characteristics
1.3.3 Hydraulic infrastructure
1.4 Characterisation of water use
1.4.1 Water uses and services by socio-economic sectors
1.4.2 Origin of water use
1.4.3 Environmental flow requirements
1.4.4 Economic analysis of water use
1.4.5 Trends and future projections
1.4.6 Water quality and environmental problems
2. Pressure, impact and risk analysis
2.1 Significant pressures impacting on water status
2.1.1 Point and diffuse source pressures
2.1.2 Abstraction and flow regulation pressures
2.1.3 Morphological pressures
2.1.4 Pressures on groundwater bodies
2.2 Impacts on surface and groundwater bodies
2.2.1 Sure impact
2.2.2 Probable impact
2.2.3 Probable impact on heavily modified water bodies, reservoirs
2.2.4 Impacts on groundwater
2.3 Water bodies at risk of not achieving a good status
2.4 Diagnosis of water quality and ecological issues
2.5 General trends and future pressures
3. Policy issues
3.1 Water management framework and major issues
3.1.1 Institutional framework
3.1.2 Legal and water rights issues
3.1.3 Droughts and water scarcity problems
3.1.4 Flood risk issues
3.1.5 Water quality issues
3.1.6 Resources overexploitation
3.1.7 Water use efficiency
3.2 Relevant water policy questions in the basin
3.2.1 Policy options and goal achievement
3.3 Information sources and stakeholder involvement
4. Environmental and resource cost analysis and methodological issues
4.1 Main water-related goods and services provided in the basin
4.2 Possible benefits and cost from that water services
4.3 Type of ERC analysis to performance
4.4 Proposed methods and tools for the valuation of ERC:
4.5 Some practical and methodological issues
5. References
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Case Study Report Serpis
1.
General case study characteristics1
1.1
Location of the case study area
The Serpis River Basin is located at the East of Spain, within the domain of the Jucar River Basin District
(see Fig. 1). It is located south to Valencia province, and north to Alicante province, mainly within the
municipal districts of Gandía, Bellreguart, Villalonga, Alquería de Aznar, Beniarrés, Muro de Alcoy,
Cocentaina y Alcoy.
Figure 1 Location of the Serpis river basin in Spain
Francia
España
Portugal
Confederación
Hidrográfica
del Júcar
Cuenca del
río Serpis
Mar Mediterráneo
Figure 2 Location of the Serpis river basin within the Jucar River Basin District
M
ed
i te
rrá
ne
o
Gandia
Rí
ío
R
Emb. Beniarrés
Bc
Río Agres
B
Río
Alcoy
ell
ar x
Río
1.2
Geographical characteristics
1.2.1
Physical general characteristics
lop
Po
Río
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Rí
Pe
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ila
oB
is
ern
a
is
rp
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1
Mainly from the Jucar RBD Art. 5. Report
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Table 1 Physical general characteristics of the basin
Characteristics
Management System
Description
Serpis
River basins
Surface are of the whole
system (km2)
Surface Serpis river basin (km2)
Serpis, Jaraco, Beniopa
Serpis river length (km)
Altitute
74.5
From 1462 m above sea level to the sea (Mediterraneam sea)
Upper basin: Valleseta, Penaguila, Barchell, Polop rivers
Middle basin: Agres river, La Encantada gully
Lower basin: Bernisa river
Main tributaries
1.2.2
990
753
Climate
Table 2 Main climatic characteristics
1.2.3
Characteristics
Description
Main climate type
Coastal Mediterranean
Climate
Mild continental Mediterranean
Average annual temperature
16.3 ºC
Average annual precipitation
630 mm
Average annual evapotranspiration
988 mm
Lithology & Geology
The Serpis river basin rises from the last mountains of the Betic range in its Mediterranean coast extreme.
The upper basin, in the proximity of Alcoy city, runs across marl deposits. The single surface reservoir in the
basin is located in Beniarres, with a geology consisting of limestone and marls. From Lorcha, the river
becomes narrow and fits into carbonate strata through the Infierno gully and until Villalonga. The current
mouth of the river is located the port of Gandía on alluvial quaternary deposits in the Plana de Gandía-Denia
coastal plain.
Population and land uses
The total population of the area is 228.389 inhabitants. Alcoy and Gandía are the main urban areas, both with
more than 60000 inhabitants. During summer, mainly due to tourism, there is a significant increase in
population, the higher increase happening in the Gandía coastal city. Table 3 shows the main land uses in the
area.
1.2.4
Table 3 Main climatic characteristics (source: GesHidro-CHJ, 2006)
Land Uses
Artificial areas
Agriculture areas
Forest
Humid zones
Water bodies
2
Area (hec.)
3,102.87
46,408.15
48,091.91
273.28
577.60
Case Study Report Serpis
1.2.5
Biotic framework
The main ecosystems in the basins are related to the 3 types of ecotypes presented in the area:
• high mineralization, high-mid Mediterranean mountain (ecotype 11; the highest upper basin)
• high mineralization, low-mid Mediterranean mountain (ecotype 9; for most of the river)
• high mineralization, low Mediterranean mountain (ecotype 7; for the lower basin)
In the Art. 5 report, specific reference conditions are defined for each ecotype, in terms of IBMW
(macroinvertebrate index), DI (diatoms index), MI (macrophytes index), and EI (ecotrophy index). Ecotype
7 has a higher IBMW and DI, although lower MI.
There is a protected zone in the river basin comprising surface water bodies supporting fish life (in
accordance with the Directive 78/659/CE), defined as “cyprinid reaches” (Fig. 3). The basin has also areas
within the Natura Network 2000, belonging to the Sites of Community Importance and Special Protection
Areas (Fig. 3).
Figure 3 Cyprinid reaches (left figure; in red). 2000 Natura Network (rigth figure)
1.3
Water system characteristics
1.3.1
Total natural runoff and available water resources
The values of total natural runoff, including groundwater discharge, are presented in Table 4.
Table 4 Surface and groundwater resources in the Serpis RB (source: Jucar River Basin Mngmt. Plan)
BASIN
Serpis river until Beniarrés dam
Serpis river between Beniarrés dam and
Villalonga
Bernisa river
Serpis river, rest of basin
Serpis river, total basin
TOTAL NATURAL RUNOFF (Mm3)
SURFACE
AQUIFER
TOTAL
RUNOFF
DISCHARGE
15,69
25,75
41,44
11,60
5,74
lp.
33,0
17,11
lp.
10,00
52,86
28,71
5,74
10,00
85,89
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Total available surface and groundwater resources are presented in Table 5.
Table 5 Surface and groundwater resources in the Serpis RB (source: Jucar River Basin Mngmt. Plan)
Characteristics
Description
Conventional resources
Superficial resources regulate
17.0 Mm3/year
Groundwater resources
105.0 Mm3/ year
Irrigation return
8.0 Mm3/ year
Total volume of available resources
130 Mm3/ year
Marginal (nonconventional) resources
Reuse sewage waters*
4.5 Mm3
* Proyected in the current Jucar RB Hydrological Plan (CHJ, 1999)
1.3.2
Streams and aquifer characteristics
Figura 4 and Table 6 and 7 show some characteristics of the streams and aquifers in the Serpis river basin.
According to the art. 5 report, there are 12 surface water bodies, 13 groundwater bodies, and 1 heavily
modified water body, the Beniarrés reservoir.
Figure 4 Serpis river and main tributaries (left) and groundwater bodies (rigth) (source: Art. 5, Jucar RBD)
Table 6 Surface water bodies characteristics (source: Art. 5, Jucar RBD)
Code
21.01
21.02
21.03
21.03.01.01
21.04
21.05
21.05.01.01
21.06
21.07
21.07.01.01
21.07.01.02
21.08
4
Water body
Serpis river: Upper basin - Pont Set Llunes
Serpis river: Pont Set Llunes – Alcoy WWT
plant
Serpis river: Alcoy WWT plant– Beniarrés
dam
Valleseta river
Beniarrés dam
Serpis river: Beniarrés dam - Lorcha
Encantada gully
Serpis river: Lorcha - Reprimala
Serpis river: Reprimala - Murta gully
Bernisa river: Cabecera – Llutxent gully
Bernisa river: Llutxent gully – Serpis river
Serpis river: Murta gully – Sea
Length Km
8.35
Category
River
River
8.05
River
19.89
23.59
6.36
8.07
10.21
10.22
10.43
5.11
24.53
8.17
River
Modified river
River
River
River
River
River
River
Modified river
Case Study Report Serpis
Table 7 Main groundwater bodies and characteristics (source: Jucar River Basin Mngmt. Plan)
HGU
Name
Surface
Highly permeable
outcrop
Highly permeable
outcrop
31 De las Agujas mountain
32 Grossa mountain
Area
(km2)
90
430
Geology
JurassicCretassic
CretássicMiocenic
Naturals exits
50
Springs
22
20
100
Albaida, Jaraco and
Cañoles rivers
11
12
100
Bullens, Albaida and
Serpis rivers
11
15
125
Jaraco and Serpis rivers,
springs, discharges to sea
70
37 Almirante Mustalla
Highly permeable
outcrop
180
38 Plana de Gandía-Denia
Highly permeable
outcrop
240
Highly permeable
outcrop
150
Cretassic
45
Girona and Racons rivers
15
210
Jurassic,
Cretassic
and
quaternary
25
Serpis and Vinalopó rivers
7
200
15
Springs
9
150
40
Springs
10
39
Almudaina-Alfaro-MediodíaSegania
40 Mariola mountain
44 Barrancones-Carrasqueta
46 Serella-Aixorta-Algar
Highly permeable
outcrop
Highly permeable
outcrop
Highly permeable
outcrop
Cretassic
and Tertiary
Extractions
Pumping Lateral transfer
(Hm3)
(Hm3)
Recharge
(Hm3/year)
15
There are some reaches of the Serpis river and the tributaries with stream-aquifer hydraulic connection.
There also some small wetlands and lagoons along the basin with important groundwater feeding.
1.3.3
Hydraulic infrastructure
The main hydraulic infrastructure consists of:
•
A dam that produces the Beniarres reservoir, with a storage capacity of 29.5 Mm3
•
Hydropower plants:
Table 8 Hydroelectric plants (source: CHJ, 1999)
Hydropower Plants
Lorcha
Rincón del Duque
Ullals
Reprimala
Power
0.68
0.12
0.13
0.34
Hydraulic jump (m)
31.0
18.3
(-) Not in use any more
•
Irrigation canals:
Table 9 Irrigation canals (source: CHJ, 1999)
Canals
Acequia Real de Gandía (Canales Bajos del Serpis)
Canales Altos del Serpis
Riegos de Bernisa
Huerta de Beniarrés y Lorcha
Pequeños regadíos del Bajo Serpis
Pequeños regadíos del Alto Serpis
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•
Wastewater Treatment Plants (WWT):
There are 30 WWT plants that get wastewater from the main urban and industrial areas, and treat aroind 29
Mm3/year. The 3 more important are: Font de la Pedra (18.5%; discharges to the river); Alcoi (25.6%;
discharges to the river); and Gandía (49.8%; discharges to the river). WWT discharge represents a high
percentage of the total streamflow: up to a 50% during winter, and a 90% during summer time (in drought
years, u to 90% of annual flow). Wastewater discharge is also responsible for up to a 90% of the annual load
of solids, organic matter and nutrients.
Figure 5 shows the main surface and groundwater bodies, hydrogeological units, urban areas and WWT
plants in the basin.
Figure 5 Serpis river basin main elements
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Case Study Report Serpis
1.4
Characterisation of water use
1.4.1
Water uses and services by socio-economic sectors
Figure 6 shows the main water uses in the basin, while industrial water consumption is shown by sectors in
Fig .7. The main water industry is textile.
Figure 6 Water uses in the basin
Figure 7 Industrial water consumption by sector
1.4.2
Origin of water use
Table 10 shows the main source of supply for the main water uses in the basin. The main springs and
groundwater intakes are shown in Fig. 8.
Table 10 Origins of water use (source: CHJ, 1999)
Use
Urban supply
Agriculture
Industry
Hydropower
Origin
Groundwater - springs
Mix (surface and groundwater)
Groundwater (municipal supply network and wells)
Surface water
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Figure 8 Main springs and groundwater intakes
1.4.3
Environmental flow requirements
According to the River Basin Management Plan (CHJ,1999), the reservoir operation is constrained by the
need to release 1000 l/s as minimum streamflow downstream the reservoir for environmental purposes (i.e.,
12 Mm3/year).
There is also a seawater intrusion problem in the alluvial coastal aquifer, and the River Basin Hydrological
Plan estimates that a minimum of groundwater discharge to the sea of 21 Mm3/year is required to stabilize
the fresh-salt water interface. This requirement necessary imposes constraints on the coastal aquifer
exploitation.
1.4.4
Economic analysis of water use
There is no specific economic studies for the urban areas supplied by the basin, but a technical study
prepared for the Jucar Water Agency used a cross-sectional econometric data study to derive a global
demand curve and estimate an average price-elasticity of the urban water demand for the whole Jucar RBD
of -0.65 (García-Valiñas, 2005; Fig. 9). So a reduction of 1% in water consumption would require a price
increase of 1.54 %.
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Case Study Report Serpis
Figure 9 Urban economic water demand curve
The total cost per habitant of the water supply and potable water treatment services, and the intake,
conveyance, distribution, wastewater treatment and discharge, for the whole Jucar RBD, is approximately
120 €/year, with an average payment of 96 €. Most of the subsidies are located in water and wastewater
treatments. The unit cost per cubic meter is 1.06 € (MMA, 2005). This figure does not include the cost of the
sewer system, 0.42 €/m3, since this is not a cost strictly associated to urban domestic water supply. The
average recovery of the costs of urban water services in 2002 was a 95% (MMA, 2005; see Fig. 10).
Figure 10 Cost recovery (% and €/m3) of water services in the Jucar RBD
(source: General Directorate of Water, Spain)
García-Mollá (2000) analyzed water demand in diverse irrigation districts in the Comunidad Valenciana
autonomous region. Two important irrigation districts with surface water are included in the study:
Comunidad de Regantes Alcoy-Bernisa and Canales Altos del Río Serpis, as well as several groundwater
irrigation districts. The main crop is orange trees, about 90% of the area, and the rest consists mainly on fruit
trees and vegetables. Table 11 shows irrigation costs.
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Table 11 Origins of water use (source: Garcia Mollá, 2000)
Water
origin
Crop
Surface
water
Average
cost
% of the
total
irrigated
land
Average
weighted
cost
0.13
(€/Hec)
Max
Min
Average
983.7
0.06
0.04
0.05
0.4
52
0.34
0.07
0.15
3.2
Orange
trees
Orange
trees
Groundwater
Volumetric cost (€/m3 )
Fig. 10 shows the demand curves (net benefit functions) for the main irrigation districts in the basin. These
demand functions were obtained by mathematical programming models, using Positive Mathematical
Programming (Blanco et al., 2004).
Figure 11 Irrigation economic water demand curves (unit water price vs. water use)
Demanda de agua Acequia real de Gandía
33
30
30
Precio del agua (cents/m3)
Precio del agua (cents/m3)
Demanda de agua Regadíos del Jaraco
33
27
24
21
18
15
12
9
6
3
0
5700
5750
5800
5850
5900
27
24
21
18
15
12
9
6
3
0
9750
5950
9800
9850
Uso de agua (m3/ha)
30
30
27
24
21
18
15
12
9
6
3
24
21
18
15
12
9
6
3
8080
8100
8120
8140
8160
0
3900
8180
4000
4100
4200
30
30
Precio del agua (cents/m3)
Precio del agua (cents/m3)
33
27
24
21
18
15
12
9
6
3
5900
5950
Uso de agua (m3/ha)
4400
4500
4600
4700
4800
Demanda de agua Pequeños regadíos alcoia y El Comtat
33
5850
4300
Uso de agua (m3/ha)
Demanda de agua Regadíos no tradicionales del Bajo Serpis
1.4.5
10000
27
Uso de agua (m3/ha)
0
5800
9950
Demanda de agua Pequeños regadíos Valle de Albaida
33
Precio del agua (cents/m 3)
Precio del agua (cents/m3)
Demanda de agua Canales Altos del Serpis
33
0
8060
9900
Uso de agua (m3/ha)
6000
6050
27
24
21
18
15
12
9
6
3
0
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
Uso de agua (m3/ha)
Trends and future projections
There are no specific projections available on the evolution of the urban, industrial, and agriculture demand
in the basin, although urban population seems to be slightly increasing in the last years. Regarding
infrastructure, there are some ongoing design and construction projects of wastewater treatment plants, for
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Case Study Report Serpis
both, new plants or upgrading and expansion of existing plants. Also, two of the main WWT plants, Alcoy
and Muro, will move to a more advance tertiary treatment with the aim of reusing wastewater from irrigation
and industrial uses for irrigation purposes.
1.4.6
Water quality and environmental problems
Water quality issues in the basin are mainly related pre-treated wastewater discharges from urban and
agricultural uses. Water quality is usually better in the upstream water bodies. In the middle and lower basin,
the water quality gets worse, mainly due to the polluted discharges from urban (Alcoy, Concentaina, Muro)
and industrial areas in the upper basin, and from Gandia city in the lower basin.
Probably the most important water quality problem occurs is the severe eutrophication process in Beniarres
reservoir, located downstream the discharge of the urban and industrial areas of Alcoi, Concentaina, and
Muro de Alcoy. It forms a hyper-eutrophic lake, with a high alga productivity level and intense alga bloom.
This is affecting the current water use for irrigation and other possible uses. Under warm summer weather, a
thermal stratification occurs, with the hypolimnion under anoxic conditions (without oxygen). This provokes
fish kills in the reservoir. The eutrophication process is also causing the deterioration of aesthetic conditions,
unpleasant odour and colour, the impossibility of recreation uses, etc.
On the other hand, water impoundment in the Beniarrés reservoir improves downstream water quality;
downstream, the status deteriorates again due to the previously mentioned industrial areas of the middle
reaches.
As previously discussed, groundwater is the basic source of urban water supply in the region. But there are
sea water intrusion problems in the coastal aquifer (Plana de Gandía – Denia aquifer), and a high nitrate and
ammonia concentration under irrigated lands, compromising it use for drinking water supply.
Other water quality impacts are:
- High abstraction pressure on the river
- Issues on protected areas (fish life, 2000 Natura Network protected areas)
- Morphological pressures (dams, weirs, channelling, etc.)
But there are also specific water quantity problems:
- Low guarantee of surface water supply for irrigation
- Drought episodes
- Eventual flood issues
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2.
Pressure, impact and risk analysis
2.1
Significant pressures impacting on water status
2.1.1
Point and diffuse source pressures
This analysis is mainly based on the Art. 5 Report and IMPRESS studies by the Jucar Water Agency.
Sources of emission are divided into point and non-point sources.
The main pressures from point sources are derived from urban wastewater discharges and industrial
discharges, mainly from textile industry. Other sources are sewer overflows, stormwater discharges, etc.
The main pressures from diffuse sources are due to agricultural water runoff and the intense use of pesticides
and fertilizers provoking a high nitrogen excess. Most surface water bodies are under significant global
pressures. Table 12 and Fig. 12 summarize these conclusions.
Table 12 Significant pressures on surface water bodies
Pressure
Drivers / Origin
Significant pressure
High and very high
• Organic load
Number of industries
Diffuse sources
High and very high
• Nitrogen excess
• Polluted soils
Water abstractions
High and very high
• Consumptive water abstractions
• Non-consumptive water abstractions
(hydropower plants)
Morphological impact
Very high
Other human pressures
Very high
• Fish species
• Land uses and fires
Global
Significant • Weighted combination of all the Very high in most surface water
bodies
Pressure
previous pressures
Point sources
Figure 12 Pressures on surface water bodies
Global pressure from point
sources
12
Global pressure from diffuse
sources
Pressure from water
abstraction
Case Study Report Serpis
Pressure from morphological
change
2.1.2
Abstraction and flow regulation pressures
Water abstraction from surface water bodies is mainly for irrigation, since urban areas are supplied from
wells.
2.1.3
Morphological pressures
The river basin has been subject to substantial morphological change mainly from the infrastructure for water
regulation and abstraction (dams, weirs, etc.), and the channelization of the final reach of the river.
Pressures on groundwater bodies
Fig. 13 shows the main significant pressures on groundwater bodies, considering point pollution, nitrogen
excess, pesticides, seawater intrusion, and pressures from water abstraction
2.1.4
Figure 13 Pressures on groundwater bodies
Groundwater
body code
080.042
080.043
080.044
080.045
080.046
080.047
080.048
080.049
080.053
080.054
080.058
080.059
080.060
080.065
080.066
080.067
Groundwater body
Sierra de las Agujas
Barig
Plana de Jaraco
Plana de Gandía
Marchuquera Falconera
Sierra de Ador
Valle de Albaida
Sierra Grossa
Villena - Benejama
Almirante Mustalla
Alfaro - Mediodía Segaria
Muro de Alcoy
Sierra Mariola
Barrancones Carrasqueta
Sierra Aitana
Serrella - Aixorta Algar
Global
pressure
080-042
YES
YES
YES
YES
YES
YES
No
No
YES
YES
YES
YES
No
No
080-044
080-043
080-049
080-046
080-045
080-048
080-047
080-054
080-053
080-059 080-922
080-058
080-060
080-067
080-065
080-066
No
YES
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2.2
Impacts on surface and groundwater bodies
2.2.1
Sure impact
Sure impact occurs when the impact of the pressures implies that the water body status is in breach of the
legislation in force. Given that the existing legislation in force only covers physic-chemical parameters, this
type of impact assessment is only based on the chemical status (the ecological status is not considered at this
stage). Fig. 14 depicts the water surface bodies under “sure impact”, according to the Art. 5 Report.
Figure 14 Sure impacts on surface water bodies
Sure impact. Priority substances,
list I
2.2.2
Sure impact. Priority substances,
list II
Sure impact – protected zones
for fish life
Probable impact
Water bodies subject to probable impact are those that most likely will not achieve the environmental
objectives defined by the WFD, or its status will be poorer than good by 2015. In this case, although current
environmental and water legislation are met for the water body, some of the following circumstances occur:
biological indices showing water quality status poorer than good, irregularities in the functioning of aquatic
ecosystems, deficiency for dissolved oxygen, salinisation, eutrophication or occurrence of substances
included in annex VIII of the WFD. Fig. 15 depicts the water surface bodies under “probable impact”,
according to the Art. 5 Report.
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Case Study Report Serpis
Figure 15 Probable impacts on surface water bodies
Probable biologic impact
IBMWP index
Probable physico-chemical
impact. Dissolve oxygen
Probable physico-chemical
impact. Chloride
Probable morphologic impact
Probable ecologic impact
Probable chemical impact
2.2.3
Probable impact on heavily modified water bodies, reservoirs
To evaluate the “probable impact” on heavily modified water bodies, the selected indicator for the case of
reservoirs was “chlorophyll a”. It is considered to be impact if the value is less than the one for the good
potential. This is the case for the Beniarres reservoir (Table 13).
Table 13 Origins of water use (source: Garcia Mollá, 2000)
Name
Beniarrés
Chlorophyll- Secchi
a (mg/m3)
(m)
173,2
0,8
Phosphorus
Probable impact
(mg/m3)
555
YES
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2.2.4
Impacts on groundwater
Groundwater bodies at risk of not achieving a good status are obtained as the worst status derived from the
assessment on groundwater quantitative (based on the comparison between the available resource and total
abstraction) and chemical status (based on the concentration of nitrates, conductivity, ammonium, and
sulphate). The main impact is due to the high nitrate concentration, because of the irrigation practices. There
is also aquifer overexploitation in the coastal aquifer 045, with high conductivity and ammonium too.
Figure 16 Probable impact, groundwater bodies
2.3
Water bodies
Probable
impact
080.042
080.043
080.044
080.045
080.046
080.047
080.048
080.049
080.053
080.054
080.058
080.059
080.060
080.065
080.066
080.067
YES
No data
No impact
YES
No impact
No data
No impact
No data
YES
YES
No impact
YES
No impact
No impact
No impact
YES
080-042
080-044
080-043
080-049
080-046
080-045
080-048
080-047
080-054
080-053
080-059 080-922
080-058
080-060
080-067
080-065
080-066
Water bodies at risk of not achieving a good status
Combining the results obtained for significant pressures and impacts in every water body it is possible to
come up with the risk assessment of failing to reach the environmental objective (see Fig. 17). Three
possibilities are considered: water bodies with high risk, medium risk and low risk (MIMAM, 2003).
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Figure 17 Criterion for risk assessment on surface water bodies
Combining the results obtained for significant pressures and impacts in every water body it is possible to
come up with the risk assessment of failing to reach the environmental objective (see Fig. 16). Three
possibilities are considered: water bodies with high risk, medium risk and low risk (MIMAM, 2003).
Most water bodies in the Serpis River are at very high or high risk of failing to achieve the environmental
objetives, mainly due to urban and industrial pollution (Fig. 18). As it was previously presented, there are
many towns (Alcoy and Muro de Alcoy in the upper basin, and Lorcha, Ayelo and Villalonga in the middle
reaches), all of which are important sources of industrial pollution.
Figure 18 Risk on surface water bodies
Risk map
Risk under study
The Beniarres reservoir is considered to be at a medium risk with probable impact.
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2.4
Diagnosis of water quality and ecological issues
The quality conditions are especially critical in two water bodies: the 21.03, which corresponds to the urban
and industrial area of the upper basin, located between the Alcoy WWTP effluent discharge and the tail of
the reservoir, and the water body 21.04, Beniarres reservoir, due to the eutrophication problems. As
discussed earlier, other significant environmental problems are referred to aquifer pollution by nitrates,
seawater intrusion and morphological alteration in the different weirs and the dam in the Serpis river,
provoking a barrier effect on fauna and flora and changes in the streamflow patterns.
With regard to the water quality and environmental objectives, the following quality indices have been
proposed by the Jucar Water Agency in a preliminary study, in which 5 categories are considered:
Table 14 Water quality indexes
Dissolved oxygen (%) DBO5 (mg O2/l)
C1
C2
C3
C4
C5
70
60
50
<40
>70
60
50
40
<3
3
5
7
5
7
9
>9
P2O5 (mg/l)
<0,4
0,4
0,4
0,7
0,7
0,7
2,3
>2,3
NO3 (mg/l)
<50
<50
<50
>50
>50
Conductivity
(µS/cm)
<600
600
800
800
1000
1000
1200
>1200
Table 15 Water quality classification and potential uses
2.5
General trends and future pressures
The trend is the reduction of pollutant discharge by:
18
-
More advanced wastewater treatments (e.g., nutrient reduction in WWTP discharges upstream the
reservoir)
-
Control of direct industrial and urban wastewater discharges and illegal water abstractions
Case Study Report Serpis
-
Better irrigation management practices
-
Wastewater reuse for agriculture and industrial applications
Regarding the quantity of the resource, the climatic change scenarios that have been proposed for the region
suggest considerable reductions in streamflow, while we can forecast a certain increase in the urban and
industrial water demand. This is a clear threat for the achievement of the good ecological status, as well as it
can lead to an increasing aquifer overexploitation and pollution. All this necessary points out the need of an
optimal and rational resource management.
3.
Policy issues
3.1
Water management framework and major issues
3.1.1
Institutional framework
The Spanish Constitution determines that the National Administration will be in charge of the management
of the hydraulic public domain whenever the river basin lies within more than one Comunidades Autónomas
(regional governments), which is the case of the Jucar RBD to which the Serpis River basin belongs. The
Jucar River Basin Authority (Confederación Hidrográfica del Júcar, CHJ), belongs to the chart of the
Ministry of Environment, within the national administration but functionally autonomous. This organization
carries out the mission of providing public service linked to water resources management over the entire area
covered by the district. The principal activities in which this public institution is engaged in are: managing
water resources, administrating the hydraulic public domain (including groundwater), elaborating,
monitoring and updating the hydrological plan, and constructing and operating hydraulic infrastructures.
3.1.2
Legal and water rights issues
The 1985 Water Law brought groundwater into the system of water use regulation along with surface water,
shifting it from private property to public domain status. The 1999 Amendment regulates water rights
transfer contracts. Only entitlement holders can enter into contracts and the water buyer must of greater or
similar priority that the water seller. This means a restriction on transfers, depending on the order of priority
established in art. 60 of the Water Law (the first priority if for domestic water supply, followed buy
irrigation, industrial uses, and others) or by the River Basin Hydrological plan, if it modifies the previous
rank.
3.1.3
Droughts and water scarcity problems
The geographical location in the Mediterranean region determines the hydrological behaviour of the basin.
The basin often suffers droughts, which can be classified as moderate, severe, and critical, according to the
Standard Precipitation Index. In general, in the last 35 years, the most representative droughts occurred on
year 1982, 1994-95 and 1999-2001. As part of the mitigation polices to solve the drought problem, we have
the Beniarres reservoir, increase of wastewater reuse, and better conjunctive use management of surface and
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groundwater resources.
3.1.4
Flood risk issues
The Serpis is a Mediterranean river, with a very irregular streamflows and prone to flood problems.
Fortunately, the dam is providing an important mitigation of the flood risk.
3.1.5
Water quality issues
See section 2.4. Eutrophication (P and N) due to agriculture is the major problem for water quality. There are
also some problems related to seawater intrusion in a coastal overexploited aquifer.
Current plans (investments in WWTP, urban drainage, emission reductions, wastewater reuse, etc) will not
be sufficient to achieve good quality.
3.1.6
Resources overexploitation
See section 2.2. and 2.3. Since most water use for urban supply is coming from groundwater, some aquifers
in the basin are currently overexploited, mainly in the lower basin. This leads to the problem of seawater
intrusion in the coastal Plana de Gandía-Denia aquifer. The River Basin Hydrological Plan estimates that a
minimum of groundwater discharge to the sea of 21 Mm3/year is required to stabilize the fresh-salt water
interface. This requirement necessary imposes constraints on the coastal aquifer exploitation.
3.1.7
Water use efficiency
Reducing water losses for irrigation by improving the applications techniques, upgrading the infrastructure
and moving to drop irrigation in some Districts that still apply surface furrow irrigation, would increase
water conservation and efficiency in the basin. However, despite the low efficiency in some irrigation
districts (around 40%), part of the water lost by percolation ends up replenishing the underlying aquifers.
Return flows constitute an important component from low-efficiency irrigation practices that should not be
discarded in any analysis.
The improvement of the efficiency of the WWT plants will allow increasing water reuse in the basin,
reducing quantitative pressures by abstractions and aquifer overexploitation, environmental flows and
seawater intrusion.
3.2
Relevant water policy questions in the basin
3.2.1
Policy options and goal achievement
The Serpis river basin has been designed as a pilot basin within the Jucar RBD for the development of the
cost-effectiveness analysis and the study of possible situations of disproportionate costs that would lead to
objectives or time derogations (following art. 4 of the WFD). The Jucar Water Agency, conjunctively with
this team of the Universidad Politécnica de Valencia, has been also a pilot basin within the second phase of
the Common Implementation Strategy. The main contribution has been within Working Group B, in the
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Case Study Report Serpis
section of Cost-Effectiveness Analysis.
A broad range of technical, economic and political measures are being under consideration with the purpose
of developing the least cost-efficient combination of measures to achieve the environmental objectives of the
WFD. Fig. 19, adapted from the Cidacos case study, MIMAM, 2000).
Figure 19 Measures for improving the status of water bodies (adapted from the MIMAM, 2000)
- Riverbank
restauration
Fluvial ecosystems
(habitat)
Water
quantity
(flow)
Water
quality
(physic-chemical)
- Demand management
- Increase in efficiency
- Increase in supply
- Treatment
- Control
- Recycling
Economic Instruments
One of the main goals in the design of the programme or measures is the reduction of pollutant discharge by
(see section 2.5.):
-
More advanced wastewater treatments (e.g., nutrient reduction in WWTP discharges upstream the
reservoir)
Control of direct industrial and urban wastewater discharges and illegal water abstractions
Better irrigation management practices
Wastewater reuse for agriculture and industrial applications
Wastewater reuse is one of the central policy options for the basin. The increase in treated wastewater reuse
from agriculture and industrial uses, mainly for crops irrigation, is expected to generate several positive
effects in the basin, as:
-
3.3
Nutrient removal, and reduction of the need of fertilizers for crops
Reduce the pressure of streamflow abstractions (by providing an additional source of supply)
Environmental enhancement (both in water quantity and quality terms)
Reduction of quantity and quality pressures on aquifer exploitation
Information sources and stakeholder involvement
The information on pressures and impacts is taken mainly from the Art. 5 Report, available at
http://www.chj.es/CPJ3/IMAGENES/imagenes.htm. Other significant references are included in the
reference section.
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Monitoring data and GIS information is available from the GESHIDRO GIS-database, developed by the
Jucar Water Agency.
The identified stakeholders are: households (drinking water, recreation), industry (process water), agriculture
(irrigation), recreation (fishing), and environmentalist groups.
4.
Environmental and resource cost analysis and methodological
issues
4.1
Main water-related goods and services provided in the basin
Most important goods and services provided by the aquatic ecosystem include drinking water, irrigation
water, recreation, and water used for industrial processes such as food processing, and textile and paper
industry. Other services include nutrient storage and uptake, carbon sequestration, biodiversity and habitat,
aesthetic values, flood protection, and water storage.
4.2
Possible benefits and cost from that water services
The benefits provided by the aquatic ecosystem can be classified into use and non-use values. Following the
classification proposed by NRC (1997), use values can be classified as extractive values (for surface water,
mainly agricultural and industrial use values; others) and in-situ values (e.g., ecological values, buffer values,
recreational values). In the case of groundwater, the extractive values correspond mainly to the municipal
uses, and in-situ values involves buffer values, but also sea-water intrusion values(fundamental for coastal
aquifers), and ecological and recreational values (since groundwater is feeding some wetlands, but also the
river as baseflow).
4.3
Type of ERC analysis to performance
Different interpretations have been given to the famous and controversial sentence of art. 9 of the WFD
about the recovery of the costs of water services, including resource and environmental costs. The Jucar
RBD, and in general, most of the south and east Mediterranean basins in Spain, have to deal not only with
water quality issues, but also mainly with severe water quantity problems. Some of these rivers can even get
completely dry during certain periods of the year when under a drought, as it happened to some reaches of
the Jucar river during the 1994-94 drought. Of course, water quality is closely linked to water quantity, and
water allocation decision have a great influence on water quality and the ecological status of the river.
The WATECO Guidance (2002) defined environmental cost as the damage costs that water uses impose on
the environment and ecosystems (including non-use values), and those who use the environment (use
values). According to the conclusions of the ECO2 Group, environmental cost can be assessed as
environmental damage cost or as damage avoidance (protection) cost (Brouwer 2004). Environmental costs
can be also defined as the costs of not reaching good ecological status by 2015, using the GES as the
reference condition for the definition of costs and benefits. The objective of our economic valuation study
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Case Study Report Serpis
can be also the estimation of environmental and resource benefits of reaching good ecological status. This
ERCB values can be included in the cost-effectiveness analysis to determine the WFD programme of
measures, but also in a cost-benefit analysis of the identified WFD programme of measures to underpin
possible derogation according to Article 4 and classification of Heavily Modified Water Bodies.
The Ministry of Environment in Spain is about to approve a legally binding Technical Guidelines for the
development of the new River Basin Management Plans (RBMP). In the last draft version of the Guidelines,
resource cost is defined as “the opportunity cost or benefit forgone when a scarce resource is allocated to a
use instead of other possible competing uses. This cost arises from an economically inefficient resource
allocation in time or among users”. The information related with the economic efficiency of water use is very
relevant in systems in which different uses compete for a scarce resource. Efficient water use is
fundamentally about recognition of water’s opportunity costs (Griffin 2005). Theoretically, if water tariffs
include this cost, an optimal resource allocation should be reached, marginal economic benefits of water
would be equal across different uses, and society’s water related welfare would be maximized. Despite the
concept’s apparent simplicity, measuring the opportunity cost of water is difficult. One option to
simultaneously value and optimally allocate water may be to establish markets or tradable permits for water
use or pollution. In the absence of well-functioning water markets, opportunity cost assessment requires “a
systems approach and a number of more or less heroic assumptions about real impacts and responses to
these” (Briscoe 1996). This assessment has to be based on a proper system to estimate the value of water for
users in the system.
In the mentioned Guidelines, environmental cost is defined as the additional cost of the measures to achieve
the good ecological status, as a way to economically assess the gap between the BAU scenario and the
environmental objectives. This is a practical, cost-based approach. However, the cost of imposing some
measures, as for example, the maintenance of minimum ecological streamflows in the river (one of the main
management decisions to achieve a good ecological status in rivers which severe low flow periods) have to
be necessary defined in terms of opportunity cost. Minimum ecological streamflows impose changes in the
system operation and water allocation; when these changes imply a reduction in the supply to other uses in
the basin, an opportunity cost exists (in the sense of forgone benefits).
A benefit-based definition of resource and environmental cost as the foregone benefit of not reaching the
GES (or, what is the same, the benefits from reaching the GES) would require the contribution of direct (e.g.,
contingent valuation) or indirect (e.g., travel cost or hedonic pricing) environmental valuation methods.
4.4
Proposed methods and tools for the valuation of ERC:
A combination of different methods and tools is expected for the valuation of ERBC.
Hydro-economic models provide useful tools for a systematic assessment of the resource opportunity cost
and the opportunity cost of the management measures required to achieve the environmental objectives (eg.,
minimum streamflow) in a water resources system. Theses values change dynamically in space and time.
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The integrated hydro-economic model can be developed “ad-hoc” for a specific system, or we can resort to
the use of generic tools integrated in Decision Support Systems (DSS). New modules have been integrated in
the DSS AQUATOOL, incorporating tools to apply the proposed methodology. AQUATOOL (Andreu et al.,
1996) is a generalized DSS for integrated water resources planning and management. Using the
AQUATOOL software, an integrated hydro-economic simulation model is currently being developed for the
Serpis river basin, including simulation of water quantity and quality in the basin for both, surface and
groundwater resources. The main water uses and hydraulic infrastructure is represented in the model.
Demands are economically represented using economic demand (net benefit) functions for agricultural,
industrial and urban uses. Legal and institutional constraints are incorporated to the model. We can also
impose water quantity-quality constraints to reach a GES, and calculate the corresponding forgone benefits
(opportunity costs).
Inductive methods will be also used for valuing environmental water goods/services
• Stated preferences methods (CV, choice experiments)
• Benefits transfer
Stated preference methods (choice experiment and/or contingent valuation) will be used to assess use and
non-use values (as willingness to pay) associated with reaching a good ecological status in 2015.
The main tools for analysis are:
• Surveys (for the stated preference methods)
• Statistical techniques (regression analysis)
• GIS based value mapping
4.5
Some practical and methodological issues
Some practical and methodological issues are:
• Availability of good data on water status, pressures and impacts, and socioeconomic environment
• Spatial and temporal aggregation for the economic analysis of the river basin water quality and quantity
issues
• The way to deal with uncertainty issues
• Integration of the different economic valuation tools and techniques for the final definition of ERCB
values
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Case Study Report Serpis
5.
References
• Andreu, J; J, Capilla; J. Ferrer; A. Solera.1996 Sistema Soporte de Decisión AQUATOOL. Universidad
Politécnica de Valencia. Escuela Técnico Superior de Caminos, Canales y Puertos. Departamento de
Ingeniería Hidráulica y Medio Ambiente. Valencia.
• Confederación Hidrográfica del Júcar. Oficina de Planificación Hidrológica. 2005. GesHidro. Soporte
digital Base de Datos y SIG. Valencia.
• Confederación Hidrográfica del Júcar. Oficina de Planificación Hidrológica. 2005. Informa para la
Comisión Europea sobre los Artículos 5 y 6 de la Directiva Marco del Agua. Demarcación Hidrográfica
del Júcar. Valencia
• Freeman, A.M. III, 2003. The measurement of environmental and resource values. Theory and methods.
Resources for the Future, Washington, DC.
• García-Mollá, Marta. 2000. Análisis de la influencia de los costes en el consumo del agua en la
agricultura Valenciana. Caracterización de las entidades asociativas para riego. Tesis Doctoral.
Universidad Politécnica de Valencia. Departamento de Economía y Ciencias Sociales. Valencia.
• Griffin, R.C., 2005. Water resource economics. The analysis of scarcity policies and projects. MIT press.
Cambridge, Massachusetts, USA. 402 pp.
• Hernández Crespo, Carmen. 2006. Estudio de la calidad de las aguas en el embalse de Beniarrés
(Alicante) mediante el desarrollo de modelos de calidad de aguas superficiales. Ejercicio Final de Carrera
Tipo II. Universidad Politécnica de Valencia. Escuela Técnico Superior de Caminos, Canales y Puertos.
Valencia.
• Jenkins, M.W., J.R. Lund, and R.E. Howitt, 2003. Using economic loss functions to value urban water
scarcity in California. Jrnl. American Water Works Association, 95(2), 58-70
• Ministerio de Medio Ambiente. Confederación Hidrográfica del Júcar. 1999. Plan Hidrológico de Cuenca
del Júcar. Anejo Nº 4. Sistemas de Explotación. Madrid.
• Villalobos de Alba, Ángel Alfonso. 2007. Análisis y de distintos tipos de sequía en la cuenca del río
Júcar. Tesis Doctoral. Universidad Politécnica de Valencia. Escuela Técnico Superior de Caminos,
Canales y Puertos. Departamento de Ingeniería Hidráulica y Medio Ambiente. Valencia.
• WATECO, 2002. Economics and the Environment. The implementation challenge of the Water
Framework Directive. A Guidance Document. Guidance document N.1, Common Implementation
Strategy for the Implementation of the Water Framework Directive, European Commission 2002.
• Young, R., 2005. Determining the economic value of water: concepts and methods. Resources for the
Future, Washington, DC.
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