• Nenhum resultado encontrado

Analysis of water management strategies for the left margin of the Guadiana river basin : implementation of a decision support tool

N/A
N/A
Protected

Academic year: 2021

Share "Analysis of water management strategies for the left margin of the Guadiana river basin : implementation of a decision support tool"

Copied!
170
0
0

Texto

(1)

A

NALYSIS OF

W

ATER

M

ANAGEMENT

S

TRATEGIES FOR THE LEFT MARGIN OF

THE

G

UADIANA RIVER BASIN

Implementation of a Decision Support Tool

D

IOGO

A

NDRÉ

P

INHO DA

C

OSTA

Dissertation submitted for partial requirements attendance for the degree on

MASTER ON CIVIL ENGINEERING —HYDRAULICS SPECIALIZATION

Supervisor: Professor Doutor Rodrigo Jorge de Oliveira Fonseca Maia

(2)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

MESTRADO INTEGRADO EM ENGENHARIA CIVIL 2007/2008

DEPARTAMENTO DE ENGENHARIA CIVIL

Tel. +351-22-508 1901 Fax +351-22-508 1446  miec@fe.up.pt

Editado por

FACULDADE DE ENGENHARIA DA UNIVERSIDADE DO PORTO

Rua Dr. Roberto Frias 4200-465 PORTO Portugal Tel. +351-22-508 1400 Fax +351-22-508 1440  feup@fe.up.pt  http://www.fe.up.pt

Reproduções parciais deste documento serão autorizadas na condição que seja mencionado o Autor e feita referência a Mestrado Integrado em Engenharia Civil -

2007/2008 - Departamento de Engenharia Civil, Faculdade de Engenharia da Universidade do Porto, Porto, Portugal, 2008.

As opiniões e informações incluídas neste documento representam unicamente o ponto de vista do respectivo Autor, não podendo o Editor aceitar qualquer responsabilidade legal ou outra em relação a erros ou omissões que possam existir.

(3)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Aos que me aguentaram nos dias em que funcionava e nos dias em que desesperantemente assim não. A uma mãe que se orgulha de algumas coisas, mas que sempre consegue dizer “mas ainda podias…”.

A um pai que orgulhosamente me deu o poder de me encantar com todos os mundos e de me apaixonar por todas as pessoas.

Um símbolo nasce de um carácter, uma moda da sua ausência. Um símbolo revela-se adimensional, uma moda finita e numérica. Um símbolo não se faz, nasce; uma moda não se revela, cria-se.

O que sabemos é o que vemos. O que vemos não pode ser mais do que sabemos. Aprendemos, depois vemos…. E só então depois sabemos o que vemos! Carácter, só depois sabedoria Diogo Costa

(4)
(5)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

ACKNOWLEDGMENTS

Ao Prof. Rodrigo Maia que exigente e pacientemente fez com que o trabalho desenvolvido fosse enquadrado e direccionado para as necessidades reais da região e das pessoas que dela directamente dependem. Para além disso, o desafio de redigir a dissertação em inglês foi encarado desde o início com grande dedicação, não tendo sido possível sem o seu empenhado e apoio. É com sincera amizade e companheirismo que recordo os momentos passados sob a sua orientação.

Agradeço igualmente ao projecto AquaStress que na mesma perspectiva ajudou para que os resultados pudessem ter alguma utilidade regional directa prática e que poderá dar continuidade ao trabalho desenvolvido.

Dirijo um agradecimento especial ao Eng. Isaurindo, director técnico do COTR (Centro Operativo da Tecnologias de Regadio), que prontamente me apoiou em todas as dificuldades e a todos os níveis. A um nível mais próximo, não posso deixar de expressar o que todos os que comigo diariamente convivem sabem, ou seja, a grande importância que tiveram para que todos os dias chegasse ao gabinete para estar com grandes amigos. Sabendo que cada um de vós sabe que de vocês falo, não particularizo ninguém mas especificamente me dirijo a cada um.

Aos meus “outros” amigos que, não directamente tiveram que lidar com mudanças de comportamento temperamental, mas que fizeram que a cada dia me renovasse e a cada espaço para descanso fizesse dele não o que precisava de ser, mas o que devia ser.

Finalmente, e com igual intensidade, agradeço á minha família que, cada um á sua especial maneira contribuiu para que me continuasse a sentir gente.

(6)
(7)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

ABSTRACT

This dissertation was developed with the aim of contributing for the definition of strategies for water resources management in the left margin of Guadiana River Basin.

Shared by Portugal and Spain, Guadiana Basin is one of the regions of the Iberian Peninsula with major water resources problems, as a result of meteorological and climatic adverse conditions

(agricultural droughts every 3 years), most frequently aggravated by inadequate irrigation and rain fed agriculture practices. The water policy in the region is much oriented to agriculture and is being enforced and promoted by the construction of several infrastructures with main agriculture purposes (namely, 30.000 ha in the Ardila new irrigation perimeter, under construction).

The regional progress is leading to a real agricultural new and complex paradigm, involving changing in landscape/land uses, agriculture practices, water sources allocation, water demand and a new water pricing policy.

On the other hand, agriculture development adds to a current deficient urban water supply, and that will surely amplify not only the current pressures on surface and groundwater but also the conflicts between those two sectors.

As a consequence of the regional overall context and transformations, the implementation of water management strategies and the development of infrastructures are aimed to face and solve water quantity and quality problems. The implementation of a DSS tool able to integrate the analysis of the existing ground and surface resources and the different demanding sectors, represents an important and useful contribution to improve knowledge and develop sustainable strategies for water management and regional agriculture policy proposals.

The WSM-DSS model allowed to formulate and evaluate short and mid-term water policies, supported by economic instruments and to address water scarcity related issues. Under possible hydrological and social scenarios, the model enabled to analyze different water management options. Finally, through the selection of indicators, the options may be compared and evaluated attending to goals defined for the region.

The integrated analysis of a complex social-economic set in a modeling perspective for decision-making support is an important innovative aspect of this dissertation. Furthermore, the possibility to envisage different future regional development perspectives, by means of allowing the assessment of different water demand and water availability scenarios, of new water infrastructures’ implementation (namely the Ardila irrigation perimeter) and of different alternative options, are important integrating innovating aspects. Finally, the development of a database aimed at a multi-scale analysis allows that assessment to be done either at the regional or at the plot scale.

The work developed benefited also from the integration of some aspects assessed in other research works developed in the AquaStress project.

Database was built with the objective of allowing future decision-makers use but also future improvements and updates, in order to give the possibility of analyzing new sustainable options and/or strategies, and to evaluate alternative water management policies.

(8)
(9)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

RESUMO

A presente dissertação foi desenvolvida com o objectivo de contribuir para a definição de estratégias de gestão dos recursos hídricos na margem esquerda da Bacia do Rio Guadiana.

Partilhado por Portugal e Espanha, a Bacia do Rio Guadiana é uma das regiões da Península Ibérica com mais problemas nos recursos hídricos, como resultado de condições meteorológicas e climáticas adversas (seca agrícola a cada 3 anos), geralmente agravadas por inadequadas práticas na agricultura, quer de sequeiro quer de rega. Deste modo, a política da água na região tem sido particularmente orientada para o sector agrícola, sendo fortemente impulsionada pela construção de novas infra-estruturas com fins agrícolas (nomeadamente áreas correspondentes aos novos 30.000 hectares do perímetro de rega público do Ardila, actualmente em construção). O desenvolvimento regional está a conduzir a região para um novo e complexo paradigma agrícola, envolvendo modificações na paisagem e nos usos dos solos, nas práticas agrícolas, na alocação dos recursos hídricos, nas necessidades de água e numa nova política de preços da água. Por outro lado, o desenvolvimento agrícola amplia os presentes défices no abastecimento urbano, o que resultará não só numa provável ampliação das pressões nos recursos superficiais e subterrâneos, como também entre aqueles dois sectores.

No contexto desse desenvolvimento e transformação regionais, a implementação de estratégias de gestão dos recursos hídricos e o desenvolvimento de novas infra-estruturas tornaram-se assim necessárias para mitigar e resolver problemas de quantidade e de qualidade desses recursos.

A utilização de um modelo de suporte á decisão capaz de integrar a análise dos recursos hídricos superficiais e subterrâneos existentes, e os diferentes sectores utilizadores de águas, representa uma importante e útil contribuição para melhorar o conhecimento e desenvolver estratégias de gestão dos recursos hídricos e propostas de políticas regionais agrícolas, de forma sustentável.

O modelo WSM-DSS permite formular e avaliar diferentes políticas de curto ou médio prazo relacionadas com a gestão directa ou indirecta dos recursos hídricos em regiões com escassez de água, e podendo estas ser apoiadas por indicadores. Baseado na formulação de possíveis cenários hidrológicos e sociais (de procura), o modelo permite analisar diferentes opções de gestão dos recursos hídricos. Finalmente, através da selecção de indicadores e de objectivos baseados nesses mesmos indicadores, as opções podem ser comparadas.

A análise integrada de paradigmas socioeconómicos complexos é orientada no sentido de poder dar um contributo para tomadas de decisão por parte de entidades com papel na gestão dos recursos hídricos. Para além disso, outros aspectos inovadores são de referir; sendo eles a possibilidade de poder integrar diferentes perspectivas de desenvolvimento regional futuro, permitindo a análise de diferentes cenários de procura e de disponibilidade hídrica, e a implementação de novas infra-estruturas (nomeadamente o novo perímetro de rega do Ardila) e diferentes opções de gestão alternativas. Finalmente, o desenvolvimento da base de dados teve como objectivo permitir a análise de resultados não só a nível regional mas também a nível específico local.

O trabalho desenvolvido pôde também beneficiar da integração de alguns aspectos resultantes de outros trabalhos específicos desenvolvidos por parceiros do projecto AquaStress.

A base de dados foi construída com o objectivo de possibilitar futuras utilizações por entidades com papel na gestão dos recursos hídricos na região, e de integrar futuros melhoramentos e actualizações, de modo a permitir aos decisores a análise de novas opções e estratégias sustentáveis, e a avaliação de políticas alternativas de gestão da água.

(10)
(11)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

GENERAL INDEX

ACKNOWLEDGMENTS ... i

ABSTRACT ... iii

RESUMO ... v

GENERAL INDEX ... vii

FIGURES INDEX ... Xiii TABLES INDEX ... Xvii SYMBOLOGY AND ABBREVIATIONS ... XiX

1. INTRODUCTION

... 1

1.1.FRAMEWORK AND OBJECTIVES OF THE DISSERTATION ... 1

1.2.ORGANIZATION OF THE DISSERTATION ... 2

2.

THE

IMPORTANCE

OF

WATER

RESOURCES

MANAGEMENT AND THE POTENTIAL CONTRIBUTION OF

DECISION SUPPORT TOOLS

... 5

2.1.WATER RESOURCES MANAGEMENT IN EUROPE ... 5

2.2.THE POTENTIAL CONTRIBUTION OF DECISION SUPPORT TOOLS ... 6

3. THE WSM-DSS TOOL CAPACITIES, CAPABILITIES AND

METHODOLOGY

OF

ANALYSIS.

PREVIOUS

IMPLEMENTATIONS

... 7

3.1.THE WSMDECISION SUPPORT TOOL ... 7

3.2.CAPACITIES AND CAPABILITIES ... 7

3.3.GENERAL TOOL METHODOLOGY OF ANALYSIS ... 8

3.4. PREVIOUS WSM TOOL IMPLEMENTATION: THE EXAMPLE OF THE RIBEIRAS DO ALGARVE CASE STUDY ... 9

4. CHARACTERIZATION OF THE CASE STUDY REGION

... 11

4.1.THE GUADIANA RIVER BASIN CONTEXT ... 11

(12)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

4.2.1.GENERAL CONTEXT AND LOCATION ... 12

4.2.2. REGIONAL PARADIGM AND MAIN PROBLEMS IDENTIFIED ... 13

4.3.INVESTMENTS, FUTURE DEVELOPMENT AND THE NEW WATER POLICY ... 13

4.4.CURRENT DEMOGRAPHIC, SOCIAL AND ECONOMIC CHARACTERIZATION... 14

4.5.CLIMATIC CHARACTERIZATION ... 17

4.6.WATER RESOURCES CHARACTERIZATION ... 18

4.6.1.HYDROGRAPHY ... 18

4.6.1.1.Guadiana River ... 19

4.6.1.2.Ardila River ... 20

4.6.2.HYDROGEOLOGY ... 21

4.6.2.1.Moura-Ficalho aquifer system ... 21

4.6.2.2. Gabros-de-Beja aquifer ... 22

4.6.2.3.Hydrogeologic systems with low water productivity and storage capacity ... 23

4.7.CURRENT WATER SUPPLY SYSTEMS AND INFRASTRUCTURES CHARACTERIZATION ... 24

4.7.1.DOMESTIC SUPPLY SYSTEMS ... 24

4.7.1.1.Public infrastructures for water storage and/or abstraction ... 24

4.7.1.2.Public systems for domestic supply ... 25

4.7.2.AGRICULTURE SUPPLY SYSTEMS ... 27

4.7.2.1.Private systems and infrastructures for irrigation supply ... 27

4.7.2.2.Future public infrastructures: The Ardila irrigation perimeter. ... 29

4.8.WATER AND WASTEWATER TREATMENT PLANS (WTP AND WWTP) CHARACTERIZATION ... 30

4.8.1.WTP’S CHARACTERIZATION ... 30

4.8.2.WWTP’S CHARACTERIZATION ... 30

5. CONCEPTUAL MODEL AND DATABASE

... 31

5.1.INTRODUCTION ... 31

5.2.WATER DEMAND ... 31

5.2.1.DOMESTIC WATER DEMAND ... 32

5.2.1.1. General methodology and conceptual models ... 32

5.2.2.AGRICULTURE WATER DEMAND ... 33

5.2.2.1. General methodology and conceptual model ... 33

5.2.2.2. General water demand patterns definition ... 35

(13)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

5.2.2.4. Data used and specific aspects ... 38

5.2.2.5. The data available. Extrapolation and assumptions used. ... 39

5.2.3.LIVESTOCK RAISING WATER DEMAND ... 40

5.3.WATER RESOURCES AND AVAILABILITY ... 40

5.3.1.SURFACE WATER ... 40

5.3.1.1. Guadiana River ... 40

5.3.1.2. Ardila River ... 42

5.3.2.GROUNDWATER ... 43

5.3.2.1. High water productivity and storage capacity aquifer: Moura Ficalho ... 44

5.3.2.2. High water productivity and storage capacity aquifer: Gabros-de-Beja ... 51

5.3.2.3. Low water productivity and storage capacity aquifers ... 53

5.4.WATER STORAGE AND ABSTRACTION INFRASTRUCTURES ... 54

6.

REGIONAL

AND

LOCAL

PROSPECTIVE

DEVELOPEMENTAL ANALYSIS. THE REFERENCE CASES

... 57

6.1. DATABASE POTENTIALITIES... 57

6.2.GENERAL TOOL SCHEMA OF ANALYSIS ... 57

6.3. METHODOLOGY FOR PAST, CURRENT AND FORESEEN FUTURE REGIONAL ANALYSIS. THE REFERENCE CASES ... 57

6.3.1.HYDROLOGICAL BASE SCENARIO DEFINITION (NORMAL) ... 58

6.3.2.BASE (SOCIAL) DEMAND SCENARIOS DEFINITION ... 60

6.3.2.1. General definition ... 60

6.3.2.2. Demand scenarios analysis: Sectoral regional water demand factors specificities ... 61

6.3.2.3. Demand scenarios analysis: Water demand evaluation and evolution ... 63

6.3.3.REFERENCE CASES (GLOBAL SCENARIOS) ... 65

6.4.COMPARISON OF THE REFERENCE CASES ... 66

6.4.1.REGIONAL GENERAL OVERVIEW ... 66

6.4.1.1. Regional indicators analysis: Domestic demand coverage ... 67

6.4.1.2. Regional indicators analysis: Irrigation demand coverage ... 67

6.4.1.3. Regional indicators analysis: Groundwater exploitation index ... 68

6.4.2.RELEVANT LOCAL SPECIFIC ANALYSIS... 69

6.4.2.1. Local specific results: Moura-Ficalho aquifer (high water productivity aquifer) ... 69

(14)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

6.4.2.3. Local specific results: Municipal irrigation demand coverage ... 73

7. METHODOLOGY AND SCENARIOS FOR WATER

MANAGEMENT STRATEGIES DEFINITION

... 77

7.1.OBJECTIVES ... 77

7.2.METHODOLOGY FOR STRATEGY FORMULATION S ... 77

7.3.SCENARIOS CONSIDERED ... 78

7.3.1. HYDROLOGICAL SCENARIOS ... 78

7.3.1.1. Normal (hydrological year sequence) ... 78

7.3.1.2. High dry (hydrological year sequence) ... 78

7.3.2.DEMAND SCENARIOS ... 79

7.3.2.1. Base demand scenario: BauAP... 79

7.3.2.2. Agricultural extreme scenario: A123... 79

7.3.2.3. Domestic extreme scenario: D12 ... 83

7.4.CASES OF ANALYISIS ... 86

7.4.1.BASE REFERENCE CASE (BauAP+Normal) ... 87

7.4.2.AGRICULTURAL EXTREME REFERENCE CASE (A123+HD) ... 88

7.4.3.DOMESTIC EXTREME REFERENCE CASE (D12+HD) ... 90

8. WATER MANAGEMENT OPTIONS ANALYSIS

... 93

8.1.INTRODUCTION ... 93

8.2.AGRICULTURE OPTIONS ... 93

8.2.1.CHANGING CROPPING PATTERNS (OA_CCP) ... 94

8.2.1.1. Regional winter cereals development (OA_CCP1) ... 94

8.2.1.2. Rain fed crops development (in private irrigation sites outside the Ardila public irrigation perimeter) (OA_CCP2) ... 96

8.2.2.REDUCTION OF AGRICULTURAL LOSSES (OA_RL) ... 98

8.3.DOMESTIC SUPPLY OPTIONS ... 100

8.3.1.WATER SUPPLY SOURCES SUBSTITUTION (OA_WSSS) ... 101

8.3.1.1. Moura municipality: SW source (Ardila River) replacement by GW source (Moura-Ficalho aquifer) (OA_WSSS1) ... 101

8.3.1.2. Mértola municipality: GW source (Low water productivity aquifers) replacement by SW source (Guadiana River) (OA_WSSS2) ... 103

(15)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

8.3.1.3. Mértola municipality: GW source (Low water productivity aquifers) replacement by SW source

(Enxoé dam) (OA_WSSS3) ... 105

8.3.2.WATER SUPPLY SYSTEMS AND/OR INFRASTRUCTURES REINFORCEMENT (OA_WSSR) ... 107

8.3.2.1. Enxoé domestic supply system reinforcement: GW abstraction (Moura-Ficalho) (OA_WSSR1) ... 107

8.3.2.2. Enxoé WTP treatment capacity reinforcement (OA_WSSR2) ... 109

8.3.3.REDUCTION OF URBAN WATER SUPPLY LOSSES (OD_RL) ... 111

9. WATER MANAGEMENT STRATEGIES ANALYSIS

... 115

9.1.INTRODUCTION ... 115

9.2.REGIONAL (FUTURE) WATER MANAGEMENT STRATEGIES ANALYSIS ... 116

9.2.1.STRATEGY 1–STRUCTURAL MEASURES ... 116

9.2.2.STRATEGY 2– REINFORCEMENT MEASURES (SYSTEMS’ UPGRADING) ... 118

10. CONCLUSIONS AND FUTURE WORK

... 123

10.1.CONCLUSIONS ... 123 10.2.FUTURE WORK ... 126 BIBLIOGRAPHY ... 127 ANNEXES ... 129 ANNEX 1 ... 131 ANNEX 2 ... 141

(16)
(17)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

FIGURES INDEX

Fig. 1: General implementation approach (WaterStrategyMan, 2002) ... 8

Fig. 2: Guadiana river basin context (the Portuguese part) ... 11

Fig. 3: Case Study region (general context) ... 12

Fig. 4: Resident population growth (%) (2000 – 2006) (data from Municipality services)... 14

Fig. 5: Activity sectors in Moura, Serpa and Mértola Municipalities ... 15

Fig. 6: Agriculture irrigation methods in Moura and Serpa Municipalities (according to data provided by COTR) ... 15

Fig. 7: Irrigated crops in Moura and Serpa Municipalities (according to data provided by COTR) ... 16

Fig. 8: Average Case Study region air temperature (ºC) (based on SNIRH) ... 17

Fig. 9: Yearly and monthly average precipitation in the CS (multi-year average) (based on SNIRH) .. 18

Fig. 10: CS hydrographic network ... 19

Fig. 11: Guadiana water flow at Alqueva dam section (adapted from INAG, 1999) ... 20

Fig. 12: Average water flow at Ardila River mouth (hm3) ... 20

Fig. 13: Main aquifers of the Case Study region ... 21

Fig. 14: Enxoé domestic supply system general context ... 25

Fig. 15: Hydraulic Infrastructures Schemes Identified in the Region ... 28

Fig. 16: Hydraulic circuit of the Ardila irrigation perimeter ... 29

Fig. 17: Mértola particular data management schema ... 33

Fig. 18: Data management scheme examples ... 34

Fig. 19: Crops water demand: (1) detailed monthly and yearly numerical data (mm/month and mm/year) and (2) graphical yearly data representation (mm/year) (defined according to FAO) ... 36

Fig. 20: Water demand for young and adult Olive tree (mm) (According to FAO and supported by ISAREG tool) ... 37

Fig. 21: Monthly water demand evolution trend along the olive tree growth period ... 37

Fig. 22: Guadiana river stream analysis and definition of stretches ... 41

Fig. 23: Conceptual model analysis for the Guadiana river modeling... 41

Fig. 24: Ardila river stream and drainage basins analysis ... 42

Fig. 25: Conceptual schema definition for modeling the Ardila River ... 43

Fig. 26: Schema of analysis for the groundwater ... 44

Fig. 29: Independent water flow regions for Moura-Ficalho aquifer ... 45

Fig. 27: Final results for general Moura-Ficalho water flow modeling (ERSHA, 2000) ... 45

Fig. 28: Horizontal water flow resulting from urban abstraction at Fonte-da-Telha, Gargalão, and Vale-de-Vargo boreholes (ERSHA, 2000) ... 45

(18)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Fig. 30: Water standing levels at the Moura

Fig. 31: Recharges indexes of Moura-Ficalho aquifer adapted from (ERSHA, 2000) Fig. 32: Conceptual GW abstraction model for region 1

Fig. 33: Analysis of GW flow depths of Moura

geological soil profile (adapted from (Costa et al, 2005) Fig. 34: Conceptual GW abstraction model for the region 2 Fig. 35: Analysis of the irrigated agriculture in the region Fig. 36: Conceptual GW abstraction model for the region 3 Fig. 37: Conceptual model for modeling Gabros

Fig. 38: Water flow along the Gabros-de

Fig. 39: Low productivity aquifers (conceptual model)

Fig. 40: Type of year meteorological classification (adapted from Deciles method) Fig. 41: Monthly domestic consumption coefficients for Moura administrative region Fig. 42: Livestock distribution along the CS region (number and percen

BauAP)...

Fig. 43: Irrigated agriculture areas (ha and %) (DScen: Bitp) Fig. 44: Irrigated areas (ha) (DScen: (a) Bau and (b) BauAP)

Fig. 45 : Moura’s domestic water demand along the year (m3) (DScen: BITP, BAU and BAU-AP) ...

Fig. 46: Water demand for stock raising (m3) (DScen: Bitp, Bau and BauAP) Fig. 47: Irrigated agriculture water demand (m3) (DScen: Bitp)

Fig. 48 : Water demand for irrigation (m3)

Fig. 49: Regional domestic demand coverage yearly evolution (m3) (Ref. Cases: Bitp, Bau and BauAP)...

Fig. 50: Regional irrigation demand coverage (m3) (Ref. Cases: Bitp, Bau and BauAP) Fig. 51: Regional groundwater exploitation index (Ref. Cases: Bitp, Bau and BauAP) Fig. 52: Moura-Ficalho aquifer (Region 2, Zone A) month water storage

Fig. 53: Region low productivity aquifers month water storage (Ref. Cases: Bitp, Bau and BauAP) Agriculture uses, - Domestic uses...

Fig. 54: Irrigation demand coverage yearly evolution in Moura Municipality (m3) (Ref. Cases: Bitp, Bau and BauAP) ...

Fig. 55: Irrigation demand coverage yearly evolution in Serpa Municipality (m3) (Ref. Cases: Bitp, Bau and BauAP) ...

Fig. 56: Irrigation demand coverage yearly evolution in Mértola Municipality (m3) (Ref. Cases: Bitp, Bau and BauAP) ...

the Left Margin of the Guadiana River Basin

Fig. 30: Water standing levels at the Moura-Ficalho aquifer (Costa et al., 2005) ... Ficalho aquifer adapted from (ERSHA, 2000) ... Fig. 32: Conceptual GW abstraction model for region 1 ... Fig. 33: Analysis of GW flow depths of Moura-Ficalho aquifer on regions 2 and 3 through the Hydro

ed from (Costa et al, 2005) ... Fig. 34: Conceptual GW abstraction model for the region 2 ... Fig. 35: Analysis of the irrigated agriculture in the region ... Fig. 36: Conceptual GW abstraction model for the region 3 ... Fig. 37: Conceptual model for modeling Gabros-de-Beja aquifer ...

de-Beja (according to ERSHA) ... Fig. 39: Low productivity aquifers (conceptual model) ... Fig. 40: Type of year meteorological classification (adapted from Deciles method) ...

c consumption coefficients for Moura administrative region ... Fig. 42: Livestock distribution along the CS region (number and percentage) (DScen: Bitp, Bau and

... Fig. 43: Irrigated agriculture areas (ha and %) (DScen: Bitp) ... Fig. 44: Irrigated areas (ha) (DScen: (a) Bau and (b) BauAP) ...

Fig. 45 : Moura’s domestic water demand along the year (m3) ...

Fig. 46: Water demand for stock raising (m3) (DScen: Bitp, Bau and BauAP) ... Fig. 47: Irrigated agriculture water demand (m3) (DScen: Bitp) ... Fig. 48 : Water demand for irrigation (m3) (DScen: (a) Bau and (b) BauAP) ...

Fig. 49: Regional domestic demand coverage yearly evolution (m3) (Ref. Cases: Bitp, Bau and ... Fig. 50: Regional irrigation demand coverage (m3) (Ref. Cases: Bitp, Bau and BauAP) ... Fig. 51: Regional groundwater exploitation index (Ref. Cases: Bitp, Bau and BauAP) ...

Ficalho aquifer (Region 2, Zone A) month water storage ... Fig. 53: Region low productivity aquifers month water storage (Ref. Cases: Bitp, Bau and BauAP)

... Fig. 54: Irrigation demand coverage yearly evolution in Moura Municipality (m3) (Ref. Cases: Bitp, Bau

...

Fig. 55: Irrigation demand coverage yearly evolution in Serpa Municipality (m3) (Ref. Cases: Bitp, Bau ...

Fig. 56: Irrigation demand coverage yearly evolution in Mértola Municipality (m3) (Ref. Cases: Bitp, ...

... 46

... 47

... 48

Ficalho aquifer on regions 2 and 3 through the Hydro-... 49 ... 50 ... 50 ... 51 ... 52 ... 52 ... 53 ... 59 ... 62

tage) (DScen: Bitp, Bau and ... 62

... 63

... 63

Fig. 45 : Moura’s domestic water demand along the year (m3) ... 64

... 64

... 65

... 65

Fig. 49: Regional domestic demand coverage yearly evolution (m3) (Ref. Cases: Bitp, Bau and ... 67

... 68

... 69

... 70

Fig. 53: Region low productivity aquifers month water storage (Ref. Cases: Bitp, Bau and BauAP) - ... 72

Fig. 54: Irrigation demand coverage yearly evolution in Moura Municipality (m3) (Ref. Cases: Bitp, Bau ... 73

Fig. 55: Irrigation demand coverage yearly evolution in Serpa Municipality (m3) (Ref. Cases: Bitp, Bau ... 74

Fig. 56: Irrigation demand coverage yearly evolution in Mértola Municipality (m3) (Ref. Cases: Bitp, ... 75

(19)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Fig. 57: Hydrological year sequence comparison (Normal and high dry) ... 78

Fig. 58: Irrigation demand coverage (A1 effects analysis) ... 80

Fig. 59: Groundwater exploitation index (A1 effects analysis) ... 81

Fig. 60: Agriculture demand (A2 effects analysis) ... 81

Fig. 61: Irrigation demand coverage (A2 effects analysis) ... 82

Fig. 62: Groundwater exploitation index (A2 effects analysis) ... 82

Fig. 63: Irrigation demand coverage (A3 effects analysis) ... 83

Fig. 64: Domestic demand (D1 effects analysis) ... 84

Fig. 65: Domestic demand coverage (D1 effects analysis) ... 85

Fig. 66: Groundwater exploitation index (D1 effects analysis) ... 85

Fig. 67: Domestic demand coverage (D1 effects analysis) ... 86

Fig. 68: Irrigation demand coverage (reference cases comparison) ... 88

Fig. 69: Groundwater exploitation index (reference cases comparison) ... 89

Fig. 70: Evaluation and regional average indicators (reference cases comparison) ... 89

Fig. 71: Domestic demand coverage (reference cases comparison)... 90

Fig. 72: Groundwater exploitation index (reference cases comparison) ... 91

Fig. 73: Evaluation and regional average indicators (reference cases comparison) ... 91

Fig. 74: IDC comparison of OA_CCP1 effects over BauAP+Normal and A123+HD ... 94

Fig. 75: Groundwater exploitation index (comparison of OA_CCP1 effects over BauAP+Normal and A123+HD) ... 95

Fig. 76: Evaluation of option (comparison of OA_CCP1 effects over BauAP+Normal and A123+HD) 96 Fig. 77: IDC (comparison of OA_CCP2 effects over BauAP+Normal and A123+HD) ... 97

Fig. 78: Groundwater exploitation index (comparison of OA_CCP2 effects over BauAP+Normal and A123+HD) ... 97

Fig. 79: Evaluation of option (comparison of OA_CCP2 effects over BauAP+Normal and A123+HD) 98 Fig. 80: IDC (comparison of OA_RL effects over BauAP+Normal and A123+HD) ... 99

Fig. 81: Groundwater exploitation index (comparison of OA_RL effects over BauAP+Normal and A123+HD) ... 99

Fig. 82: Evaluation of option (comparison of OA_RL effects over BauAP+Normal and A123+HD) ... 100

Fig. 83: Domestic demand coverage (comparison of OD_WSSS1 effects over BauAP+Normal and D12+HD) ... 101

Fig. 84: Groundwater exploitation index (comparison of OD_WSSS1 effects over BauAP+Normal and D12+HD) ... 102

Fig. 85: Evaluation of option (comparison of OD_WSSS1 effects over BauAP+Normal and D12+HD) ... 102

(20)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Fig. 86: Domestic demand coverage (comparison of OD_WSSS2 effects over BauAP+Normal and D12+HD) ... 103 Fig. 87: Groundwater exploitation index (comparison of OD_WSSS2 effects over BauAP+Normal and D12+HD) ... 104 Fig. 88: Evaluation of option (comparison of OD_WSSS2 effects over BauAP+Normal and D12+HD) ... 104 Fig. 89: Domestic demand coverage (comparison of OD_WSSS3 effects over BauAP+Normal and D12+HD) ... 105 Fig. 90: Groundwater exploitation index (comparison of OD_WSSS3 effects over BauAP+Normal and D12+HD) ... 106 Fig. 91: Evaluation of option (comparison of OD_WSSS3 effects over BauAP+Normal and D12+HD) ... 106 Fig. 92: Domestic demand coverage (comparison of OD_WSSR1 effects over BauAP+Normal and D12+HD) ... 108 Fig. 93: Groundwater exploitation index (comparison of OD_WSSR1 effects over BauAP+Normal and D12+HD) ... 108 Fig. 94: Evaluation of option (comparison of OD_WSSR1 effects over BauAP+Normal and D12+HD) ... 109 Fig. 95: Domestic demand coverage (comparison of OD_WSSR2 effects over BauAP+Normal and D12+HD) ... 110 Fig. 96: Groundwater exploitation index (comparison of OD_WSSR2 effects over BauAP+Normal and D12+HD) ... 110 Fig. 97: Evaluation of option (comparison of OD_WSSR2 effects over BauAP+Normal and D12+HD) ... 111 Fig. 98: Domestic demand coverage (comparison of OD_RL effects over BauAP+Normal and D12+HD) ... 112 Fig. 99: Groundwater exploitation index (comparison of OD_RL effects over BauAP+Normal and A123+HD) ... 112 Fig. 100: Evaluation of option (comparison of OD_RL effects over BauAP+Normal and A123+HD) . 113 Fig. 101: Evaluation and regional average indicators (Strategy 1) ... 118 Fig. 102: Evaluation and regional average indicators (Strategy 2) ... 120

(21)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

TABLES INDEX

Table 1: Population distribution in the Case Study region (in 2001) (INE, 2001) ... 14

Table 2: General characteristics of Moura-Ficalho aquifer system (ERSHA, 2000) ... 22

Table 3: General characteristics of Gabros-de-Beja aquifer system (entire aquifer) (ERSHA, 2000) .. 23

Table 4: General characteristics of the low water productivity and storage capacity aquifer systems (INAG, 2000) ... 23

Table 5: Moura Municipality supply systems ... 26

Table 6: Serpa Municipality water supply systems ... 26

Table 7: Mértola Municipality supply systems (inside de CS) ... 27

Table 8: Irrigation methods efficiency (COTR) ... 36

Table 9: Olive water demand (due to regional irrigation strategy) (mm/month) (COTR) ... 38

Table 10: Criteria used to complete the data available for the agriculture exploitations inventory (data: 2005 irrigated agriculture inventory) ... 39

Table 11: Lack of data management criterion ... 55

Table 12 : Monthly averaged precipitation in the CS region (mm) ... 59

Table 13: Meteorological year’s classification according to Deciles method defined ... 60

Table 14: Social (Demand) scenarios ... 61

Table 15: Reference Case definition (demand and hydrological scenarios combination) ... 66

Table 16: High dry (HD) hydrological year sequence ... 79

Table 17 : Case Study region goals ... 87

Table 18: Evaluation scores for different period of analysis (BauAP+Normal, A123+HD and D12+HD) ... 115

Table 19: Strategy 1 - options implementation sequence ... 116

(22)
(23)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

SYMBOLOGY AND ABBREVIATIONS

AquaStress – European I.P. Project on “Mitigation of Water Stress through new Approaches to Integrating Management, Technical, Economic and Institutional Instruments”

COTR – Centro Operativo de Tecnologias de Regadio, Irrigation Technology Operation Center EFMA – Empreendimento de Fins Múltiplos do Alqueva, Alqueva Dam Multipurpose Infrastructure System

INAG – Instituto da Água, National Portuguese Water Institute

INE – Instituto Nacional de Estatística, National Portuguese Statistical Service

INETI - Instituto Nacional de Engenharia, Tecnologia e Inovação, I.P., National Institute for Engineering, Technology and Innovation

ISAREG - Irrigation scheduling simulation model (Teixeira, 1994) FAO – Food and Agriculture Organization of the United Nations

SNIRH - Sistema Nacional de Informação de Recursos Hídricos, National Information System on Water Resources

WSM-DSS – Water Strategy Man Decision Support System

CS – Case Study EU – European Union GW – Groundwater SW – Surface water

WTP – Water Treatment Plant (ETA)

WWTP – Wastewater Treatment Plant (ETAR)

Bitp – Business in the past Bau – Business as usual

BauAP – Business as usual with Ardila irrigation perimeter implementation DScen – Demand scenario

GEI – Groundwater exploitation index DDC – Domestic demand coverage IDC – Irrigation demand coverage HD – High dry

CCP – Changing cropping patterns RL – Reduction of losses

(24)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

WSSR – Water supply source reinforcement ST – Strategy

(25)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

1

INTRODUCTION

1.1.FRAMEWORK AND OBJECTIVES OF THE DISSERTATION

The globalization phenomenon has promoted a world scale economic competition and intense internationalization of markets. In fact, together with intense global competition, conflict of uses began logically to occur more frequently not only at local regional scale but currently also at the world scale level.

The Alentejo region is characterized by low precipitation and low water storage capacities and strategic water reserves. In fact, the regional economic activities were adapted to its typical general dry and water scarcity characteristics. The rain fed agricultural practices together with livestock raising activities were the most significant in the primary economical sector of activity.

The development policy of the region was always strongly focused on agriculture. In accordance, together with the urgent necessity of developing a strategic water reserve, the Alqueva multi-purpose system was conceptualized and began to be built in 1976.

Focused mainly in energy production and irrigation for agriculture, the construction of the multipurpose system started promoting a change on the old agriculture paradigm, until then strongly characterized by traditional rain fed practices, as referred previously.

The general objective of the present dissertation is the analysis of possible options and strategies able to complement and contribute to the sustainable development of the region. The work developed was based in the implementation of a decision support tool, the WSM-DDS, previously successfully used in Algarve region.

The research work focused in the Portuguese part of the left margin of the Guadiana River basin, region commonly affected by droughts. In fact, the Alqueva dam multipurpose system will particularly affect this region through the construction of a public irrigation perimeter. Based on a hydraulic circuit that integrates eight dams and is supported upstream by Pedrogão dam storage reservoir, connected itself with Alqueva dam storage reservoir, the new public perimeter will benefit a total of 30 thousand hectares of irrigated areas.

(26)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

The research work was developed integrated in an European project, the AquaStress project – “Mitigation of water stress thought new approaches to integrating management, technical, economic and institutional instruments”, started in February 2005, with the contract n.511231 of the European Commission and integrated in the 6th Framework.

The research work presented in the dissertation corresponds to a specific task of the overall project, and was entirely carried out by the author Diogo Costa, under supervision of Prof. Rodrigo Maia. The specific data or research work carried out by other partners of the project is clearly mentioned along the document in proper place.

1.2.ORGANIZATION OF THE DISSERTATION

The dissertation is composed by ten chapters, this first introductory (Chapter 1) and the next two related with also introductory and general contextualizing subjects (Chapters 2 and 3).

The research work developed can be divided in two main phases. The first stage embraced tasks related with the database development and its calibration (Chapters 4, 5 and 6), The database calibration shall be meant as the adjustment of the conceptual models used in order to translate real water availability and demand interrelationships and/or by validating the input data having in attention the adequacy of the modeling results to real site characteristics (e.g., to adjust local low productivity aquifer usable recharge values having in attention usual water levels on wells). Concluded the first stage, related issued with the analysis of water management options and strategies were developed and analyzed (Chapters 7, 8 and 9). Finally, conclusions and considerations about future work are developed (Chapter 10).

More detailed resume of each chapter is described focusing particular issues addressed.

On chapter 2, a brief reference to the European water management practices and on its importance is presented. The potential contribution of decision support tools for water management is also addressed.

Chapter 3 describes the capacities and potentialities of the decision support tool used, the WSM-DSS. Together with a general presentation of the tool, it is presented also a brief resume of the European project WaterStrategyMan, responsible for building the DSS tool. Finally, as example, a case of previous tool implementation is generally described in relation to issues addressed and results achieved.

On chapter 4, a general characterization of the CS region is presented. Embracing the different Municipalities, water uses and water sources and infrastructures, this chapter focus on giving general information about issues with role on region’s water context. In fact, the issues focused were incorporated in the database, leading to the possibility of being addressed and integrated in the simulations analyses.

(27)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Chapter 5 presents the methodology and conceptual models used to model the different natural and human agents with role in water related issues. The research work presented in this chapter is extremely important because it describes the way the bridge between “real” region and the model functioning was conceptualized. The special relevance of this chapter is related with the fact the work developed in this stage was used as basis for the subsequent chapters.

On Chapter 6, past, current and future expected regional development paradigms are simulated with the objective of calibrating the model and developing regional and specific local analysis on water sources and uses.

Chapter 7 describes the methodology used to analyze the efficiency and efficacy of options and strategies implementation.

On chapter 8, analysis of options implementation impacts are carried out individually aiming at identifying the efficiency of each of them. To support identifying the most effective options, evaluations are carried out in relation to a regional goal potential contribution. In addition, the individual options analysis will be important for a solid choice of the most suitable ones to be integrated in the strategies to formulate.

Chapter 9 integrates the analysis of water management strategies. The analysis is supported by the evaluation criterion used in previous chapters. The analysis is carried out based on a base reference case and on two extreme reference cases, also previously used in the analysis of options.

Finally, on chapter 10, conclusions and description of envisaged future work close the research work developed and the dissertation document.

(28)
(29)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

2

THE IMPORTANCE OF WATER

RESOURCES MANAGEMENT AND

THE POTENTIAL CONTRIBUTION OF

DECISION SUPPORT TOOLS

2.1.WATER RESOURCES MANAGEMENT IN EUROPE

Before the Water Framework Directive (WFD) formulation and approval, the European Union water policy ad already addressed important environmental issues, namely related with pollution and nutrients due to agriculture and industry emissions. However, analysis on the implementation of the existing legislation revealed low existence or effectiveness of the measures undertaken by some Member States (in some cases very low). That could be correlated to adequate corresponding investments made over the last decades by only some countries/regions, where those problems have been largely resolved.

In fact, although integrated water resources management has been a general goal for a long time, there was no legislative incentive to fully implement this concept within a short time frame in most of the EU countries.

By 2000, the EU Water Framework Directive was then adopted on a common water resources policy EU guidance document. The Directive establishes a common framework for sustainable and integrated management of all types of water. Groundwater, inland surface water, transitional water and coastal water management are required to be managed integrated. In addition, other factors like the social context and economic implications should be taken into account.

The objective of the Directive is to reach good status of all water bodies in the EU member states and associated states by 2015. Nevertheless, according to a communication from the Commission of the European Communities to the European Parliament and the Council (Commission of the European Communities, 2007), the percentage of water bodies meeting all the WFD goals is currently low, being is some Member States not more than 1%.

The 2015 deadline is at major risk to be achieved in densely populated areas and in regions with intensive and often unsustainable water use.

The adverse meteorological condition of the countries located in the Mediterranean part, where water scarcity is becoming more severe in many cases, reinforces the necessity of sharing surface (rivers and

(30)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

lakes) and ground water resources with the objective of meeting the growing water demand but also the goals defined in the Directive.

The conflicts between those regions, on which Portugal is included, result from disagreement concerning of shared water resources quantitative and qualitative issues. Therefore, cooperative arrangements to jointly manage shared water resources are becoming necessary, not only to avoid conflict but also to optimize utilization and to achieve water security.

2.2.THE POTENTIAL CONTRIBUTION OF DECISION SUPPORT TOOLS

The potential contribution capacity of decision support tools for achieving the objectives promoted by the WFD, are extremely relevant. In fact, the possibility of incorporating surface and ground waters, as well as different water users, in a large spatial scale, can contribute to the development of river basin water management plans, important issue addressed by the Directive.

In addition, the Directive mentions also the necessity of all Member States to take into account the principle of water services costs recovery. In some cases, these tools allow to incorporate economic analysis to support the assessment of most appropriate water management options and strategies. Flowing that, different tools have been developed aiming at integrated river basin planning and management. As examples there are the Mike Basin tool and Aquatool.

The Mike Basin tool was developed by the Danish Hydraulic Institute (DHI), an independent self-supporting research and consulting organization, affiliated to the Danish Academy of Technical Sciences. The Mike Basin was applied to several regions, such as the Zambezi River (crossing several countries in Africa), the Upper Yangtze River (China), the Oranie River (Algeria) and the Srepok River (Vietnam). The tool allows basin wide representation of water availability, to incorporate sector water demands, multi-purpose reservoir operation, transfer/diversion schemes, and possible environmental constraints.

The Aquatool was developed by the Water Resources Engineering Group, part of the department of Hydraulic engineering and Environment of the "Universidad Politécnica de Valencia" (Spain) and was already applied in several Spanish basins, such as Júcar, Segura and Tejo; as well as in regions on Argentina, Brazil and Italy. The tool allows developing mapping schemas, to incorporate base numerical information and allows graphical analysis of the results. The model does not integrate economic analysis.

(31)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

3

THE WSM-DSS TOOL CAPACITIES,

CAPABILITIES AND METHODOLOGY

OF ANALYSIS. PREVIOUS

IMPLEMENTATIONS

3.1.THE WSMDECISION SUPPORT TOOL

The WSM-DSS tool was developed under a four year European Project started in 2002, the WaterStrategyMan project, on which the calibration was supported by its implementation on six Case Studies (Greece, Italy, Spain, Portugal, Cyprus and Israel) (http://environ.chemeng.ntua.gr/WSM/). The project aimed at developing an integrated water resources management tool that could take into account economic, technical, social, institutional and environmental aspects to meet both directly and indirectly the EU requirements concerning preservation and enhancement of water resources but still addressing also regional development.

Through the analysis and exploitation of those case studies, guidelines and protocols were defined and a decision support tool was developed and provided to decision makers to improve water resources management, by enabling to reflect the specificities of each region and to present simple but exhaustive results.

Generally, the WSM-DSS allows decision-makers to address water scarcity related issues by formulating and evaluating short and mid-term policies, supported when necessary by economic instruments. Taking into consideration any possible hydrological and social scenarios, the model enables to analyze different water management options and strategies. Finally, through the selection of indicators, the options can be compared and evaluated attending to goals defined for the region.

3.2.CAPACITIES AND CAPABILITIES

Generally, the main objective projected for the implementation of this tool is related with the definition of water management options and strategies. Aiming at achieving that, the model’s implementation allows:

(32)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

(1) Describing the existing situation in a case study area, in terms of hydraulic and environmental characteristics of man-made and natural water systems;

(2) Assessing the state of the water system under different aspects such as available water sources and specific water availabilities, water use practices and economic aspects;

(3) Defining and applying alternative strategies for an integrated water resources management based on technical management options/actions;

(4) Analyzing the behavior of the water sources in relation to different scenarios and to alternative strategies’ implementation. The scenarios and strategies are both defined taking into consideration the overall water availability in the region and the water demands patterns from the different users; (5) Evaluating the impacts of actions and/or policies through a multi-criteria approach defined taking into consideration local, national or international legal constraints and directives.

3.3.GENERAL TOOL METHODOLOGY OF ANALYSIS

The implementation of the tool can be structured in three main stages. The first phase embraces the effort related with the definition of drivers and data collection (numerical data but also GIS information). The second phase, involves the interactive process of adaptation of the model to the region, through the analysis of results and calibration of the database, aiming at the definition of Reference Cases. Those shall be understood as regional developmental scenarios under which the effectiveness of options and strategies to be potentially implemented will be analyzed and evaluated. Finally, the last stage is related with the definition and simulation of water management options and strategies (Fig. 1).

Input data (Drivers)

Pre processor

(Pressures) Water Allocation (State) Post processor (Impacts) Strategy Definition (Responses) Precipitation Evaporation Population Growth Land Use Patterns

Available Supply Forecasted Demand Water quality of supply sources Waste generation Impacts - Environmental - Social - Economic Policy Options - Supply Enhancement - Demand Reduction - Pollution Prevention - Institutional Capacity - Socio-Economic Instruments Water balance Water Pollution Water Cost Demand Feedback

(33)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

While options are singular and individual ??? actions or measures (e.g., building a dam, change crop patterns, increase water tariffs, etc.), strategies are plans combining those options during the analysis time period.

For the last stage, the tool incorporates a section to support the simulation of options and strategies. In fact, large scale options implementation is significantly supported by a section developed for that specific purpose. The tool allows to simulate options such crop changing patterns, improvement in irrigation techniques, reduction of losses, improvement of reservoir’ operating rules, wastewater reuse, water pricing and reallocation of water sources (with the possibility of considering new infrastructure building).

The evaluation of options and strategies is possible to undertake based on indicators related with efficiency and environmental and economic aspects.

3.4.PREVIOUS WSM TOOL IMPLEMENTATION: THE EXAMPLE OF THE RIBEIRAS DO ALGARVE CASE STUDY

As mentioned above, the WaterStrategyMan European project was responsible for the development of the WSM-DSS tool. From the six Case Studies developed to support the development of the tool, by the implementation of it in different region, the Ribeiras do Algarve River Basin was the site chosen for the Portuguese Case Study.

Ribeiras do Algarve River Basin is located in the southern stretch of the Portuguese territory. Occupying a total area of about 3837 km2, the River Basin embraces 18 Municipalities. In this region,

deep changes occurred on water management practices during the last decades, for long dependent mostly exclusively on GW sources. In fact, the water demand growth, consequence of tourism development, lead to an increase on overexploited aquifers. As consequence, the degradation of those water sources started occurring, namely translated into salinisation problems and water quality deterioration, transforming most of them non-reliable for domestic use.

By the time of the WSM research project, Querença-Silves aquifer was considered to be the only one remaining in Algarve region with water in quantity and quality necessary to be used sustainably for domestic water supply abstraction.

To assure reliable water supply for resident and tourist population and for agriculture, by the end of the 90’s, a new primary water supply system for urban supply was then established. That system, which is mostly based on surface water sources, supplied 85% of the total urban water consumption in 2002. The remaining regional urban water supply was supported by groundwater under the Municipalities responsibility. Industrial consumption represented only less than 1,5% of total urban consumption. Although tourism mobilized the major economic activities in the region, agriculture was still the main water consumer in the basin (65%), using mainly groundwater (86%).

(34)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

As part of the new developmental strategy of increasing tourism activity, golf courses implementation also increased. By the end of 2003, about 25 golf courses already existed in the Algarve River Basin, representing approximately 41% of the total existing in Portugal.

Although the domestic supply systems were already significantly improved, are still to be solved other water issues related with deficient infrastructures, poor groundwater quality, high values of secondary water supply network losses (16% to 61%) and inadequate irrigation methods, urging the implementation of alternative water management measures.

The implementation of the DSS tool followed the following methodology: (i) establishment of calibrated scenarios as basis for analysis, (ii) identification of objectives and criteria, (iii) identification of options to solve the problems, (iv) estimation of the impacts of the different options and (v) evaluation using different indicators related with efficiency, environmental and economic issues.

With a close contact with regional institutions responsible for domestic public water supply, with special emphasis for Águas do Algarve, the implementation of WSM made possible the analysis of regional water management strategies, mostly focused on foreseen water scarcity scenarios and potential development expectations.

In short resume, the implementation of the models revealed that if cost recovery goals were imposed strategies mostly relying on small-scale measures and on exploitation of both surface and groundwater could reach similar or even better results than strategies based on structural measures.

(35)

Analysis of

4.1.THE GUADIANA RIVER BASIN

The Portuguese part of the Guadiana river

Algarve with relatively different main characteristics and specificities

Fig. 2: Guadiana

Alentejo region, where the major part characterized as one of the poorest regions

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

CHARACTERIZATION OF THE CASE

STUDY REGION

UADIANA RIVER BASIN CONTEXT

of the Guadiana river basin lies in two administrative regions, Alentejo and Algarve with relatively different main characteristics and specificities (Fig. 2).

Legend

Alentejo region Algarve region Guadiana River basin (Portuguese part)

Guadiana River Ardila River

Guadiana river basin context (the Portuguese part)

the major part of the Portuguese Guadiana River basin is characterized as one of the poorest regions in the EU, currently presenting demographic

the Left Margin of the Guadiana River Basin

4

CHARACTERIZATION OF THE CASE

STUDY REGION

two administrative regions, Alentejo and

Legend

Alentejo region Algarve region Guadiana River basin (Portuguese part)

Guadiana River Ardila River

basin is located, is demographic decrease and

(36)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

short economic and social development. Regarding the economical sector, this administrative region is devoted essentially to agricultural activities, mainly characterized by rain fed crops.

Algarve’s river basin part regards the downstream area, embracing the estuarine region. Despite being a region with significant development over the last decades, especially due to tourism, the demographic dynamic of that river basin area is still low comparatively with the regions of Algarve located outside the basin. In terms of economic sectors, the tourism and agriculture together with stock raising activities are the most relevant.

4.2.THE CASE STUDY REGION

4.2.1.GENERAL CONTEXT AND LOCATION

The Case Study is focused on a region on the left margin of the Portuguese Guadiana river basin, limited by this river (west), the border with Spain (east) and Moura Municipality administrative limits (north) (Fig. 3). Embracing also Serpa and part of Mértola Municipalities, the CS region is a mainland bordering region with the lowest density (17 inhab/ km2), the lowest PIB and the biggest index of social desertification of the country.

Legend

Moura, Serpa and Mértola Municipality regions Communities embraced by the CS

Guadiana River Ardila River

Alqueva and Pedrogão dams Alqueva dam storage reservoir

Fig. 3: Case Study region (general context) SPAIN P O R T U G A L

(37)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Aiming at social and economic development not only of the CS Municipalities but also the overall Alentejo region, investments were envisaged for decades. In 2002 the construction of Alqueva dam is concluded. Alqueva dam is the main dam of a multipurpose complex system built with the objective of setting up a strategic water reserve and providing guarantee of water supply for irrigation, for the population and for industry (EDIA 2002).

Inside the CS study region, other important dams, with special relevance for Pedrogão, the main downstream dam of Alqueva, will directly affect the region through a complex network planned mainly for agriculture proposes.

4.2.2. REGIONAL PARADIGM AND MAIN PROBLEMS IDENTIFIED

This region is typically a drought’s vulnerable Mediterranean area (occurring every 3 years, according to INAG), as a result of meteorological and climatic adverse conditions and that fact is most aggravated by inadequate irrigation and rain fed agriculture practices. Implementation of water management strategies and development of infrastructures are aimed to face and solve water quantity and quality problems.

In fact, the main economical activity in the region is agriculture and the water policy is then much oriented to it. The current change on land uses began to transform landscape, leading to a real new and complex agricultural paradigm, involving changing crop patterns, agriculture practices, water sources allocation, water demand and a new water pricing policy.

On the other hand, agriculture development adds to a current deficient urban water supply, and that will surely amplify not only the current pressures on surface and groundwater but also the conflicts between those two sectors. In fact, the promoted regional development is already leading to some problems, namely in the existing water sources.

4.3.INVESTMENTS, FUTURE DEVELOPMENT AND THE NEW WATER POLICY

Part of a huge EU relevant investment in irrigation agriculture, the Ardila public irrigation subsystem, currently under construction, is being developed in the Case Study region.

The expected development of the irrigation Ardila sub-system and the national and E.U. agricultural policies lead already to a strong irrigation development in the CS region (where the rain fed agriculture and cultures were, and still are, traditional) in the last years, namely on olive tree and vineyards.

The Ardila irrigation perimeter will benefit 30000 hectares of irrigated areas in the communities of Santo Agostinho and São João Baptista in Moura municipality and the communities of Brinches, Pias , Salvador, Santa Maria and Vale de Vargo in Serpa municipality, and is foreseen to start operating still in 2008. The estimated water requirement for the expected 7 irrigation blocks is 197.5hm3 for an

(38)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

4.4.CURRENT DEMOGRAPHIC, SOCIAL

Demographically the municipalities inside population density (Table 1), reflecting

Table 1: Population distribution

Administrative Regions

Moura Serpa

Mértola (region inside CS) CS region (total)

The Case study region population records tendency that lasts for decades, mainly driven by migration phenomenon is mainly due to

also related to the poor soil type, especi

Fig. 4: Resident population growth (%) (2000

the Left Margin of the Guadiana River Basin

SOCIAL AND ECONOMIC CHARACTERIZATION

Demographically the municipalities inside the Guadiana Case Study Region are characterized by low reflecting general Alentejo region situation.

: Population distribution in the Case Study region (in 2001) (INE, 2001)

Area (Km2)

Population

Resident Density (hab/km2)

957,72 16590 19,78

1103,74 16823 15,34

552,99 5036 10,10

2614,45 38449 15,07

records show a decrease over the last years (Fig. 4), following a tendency that lasts for decades, mainly driven by population ageing and rural-urban migration migration phenomenon is mainly due to the population search of better living conditions, and that is

soil type, especially at Mértola region.

: Resident population growth (%) (2000 – 2006) (data from Municipality services)

Guadiana Case Study Region are characterized by low

, following a urban migration. The ter living conditions, and that is

(39)

Analysis of

Moura and Serpa Municipalities are divided in 8 and 7 sub respectively. The most of Mértola

administrative regions of it place

Economically, the tertiary sector is the most important employees of this sector work also in agriculture, as a secondary sector, agro-alimentary industries are the more volumes.

Fig. 5: Activity sectors in Moura, Serpa and Mértola Municipalities

The agriculture sector went through a deep changing process since the last decade.

rain fed agriculture practices are still the most common in the Case Study region, irrigation become very popular (Fig. 6).

Fig. 6: Agriculture irrigation methods

Mostly promoted by the new Ardila irrigation perimeter, the intensive development of

practices began mainly since 1995. In fact, the drip irrigation methods become very popular mostly due to the Olive also intensive development.

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Moura and Serpa Municipalities are divided in 8 and 7 sub-administrative regions (freguesias), Mértola Municipality is placed outside the Case Study region,

placed inside the region under investigation (Fig. 3).

tertiary sector is the most important activity, although a significant employees of this sector work also in agriculture, as a complementary activity (

alimentary industries are the more representative both in number and in sale

Activity sectors in Moura, Serpa and Mértola Municipalities

through a deep changing process since the last decade.

practices are still the most common in the Case Study region, irrigation

Agriculture irrigation methods in Moura and Serpa Municipalities (according to data provided by COTR)

Mostly promoted by the new Ardila irrigation perimeter, the intensive development of

practices began mainly since 1995. In fact, the drip irrigation methods become very popular mostly due to the Olive also intensive development.

the Left Margin of the Guadiana River Basin

administrative regions (freguesias), is placed outside the Case Study region, with 3

sub-, although a significant part of the activity (Fig. 5). In the both in number and in sale

through a deep changing process since the last decade. In fact, although practices are still the most common in the Case Study region, irrigation has

(according to data provided by COTR)

Mostly promoted by the new Ardila irrigation perimeter, the intensive development of irrigation practices began mainly since 1995. In fact, the drip irrigation methods become very popular mostly

(40)

Analysis of Water Management Strategies for the Left Margin of the Guadiana River Basin

Between 1995 and 2005, the irrigated areas

areas using drip irrigation methods was almost inexistent but in ten years new four thousand agricultural areas started using that irrigation method

The Olive crop was, and still is, the most wide spread crop in the Case Study region

accordance with the previous figure (Fig. 6) irrigation practices were almost inexistent not only on the areas using this crop but also in general.

The irrigation practices development o also using those practices (Fig. 7).

1996

Fig. 7: Irrigated crops in Moura and

The increase on the use of irrigation practices crop productions as a consequence of the the existence of the Ardila public irrigation agriculture to get in the global competition.

region, although more expressive investments were felt over the last year on Vine, Beetroot and Maize crops.

the Left Margin of the Guadiana River Basin

Between 1995 and 2005, the irrigated areas increase more than twelve times. In 1995 the agriculture areas using drip irrigation methods was almost inexistent but in ten years new four thousand agricultural areas started using that irrigation method.

, and still is, the most wide spread crop in the Case Study region. Nevertheless, in accordance with the previous figure (Fig. 6) irrigation practices were almost inexistent not only on the areas using this crop but also in general.

The irrigation practices development over the last years was intensive in Olive but other crops started

2000 2005

and Serpa Municipalities (according to data provided by COTR)

practices, starting intensively in 1995, aimed mainly at the increase of the world scale agricultural competition. irrigation perimeter has given the possibility for the genera

to get in the global competition. The development affected almost all existing crops in the region, although more expressive investments were felt over the last year on Vine, Beetroot and Maize increase more than twelve times. In 1995 the agriculture areas using drip irrigation methods was almost inexistent but in ten years new four thousand

Nevertheless, in accordance with the previous figure (Fig. 6) irrigation practices were almost inexistent not only on the

crops started

(according to data provided by COTR)

mainly at improving competition. In fact, for the general region’s development affected almost all existing crops in the region, although more expressive investments were felt over the last year on Vine, Beetroot and Maize

Imagem

Fig. 3: Case Study region (general context) SPAIN
Table 4: General characteristics of the low water productivity and storage capacity aquifer systems (INAG, 2000)
Fig. 18: Data management scheme example
Fig. 21: Monthly water demand evolution trend along the olive tree growth period
+7

Referências

Documentos relacionados

Remelted zone of the probes after treatment with current intensity of arc plasma – 100 A, lower bainite, retained austenite and secondary cementite.. Because the secondary

The probability of attending school four our group of interest in this region increased by 6.5 percentage points after the expansion of the Bolsa Família program in 2007 and

The first harvest, in general, favored the occurrence of rotten kernels for all studied genotypes and, therefore, all accessions evaluated showed values above the maximum

Conforme debatido anteriormente nos capítulos teóricos deste trabalho, com o avanço das TIC, sobretudo após a ascensão da web 2.0, uma infinidade de ferramentas

Na hepatite B, as enzimas hepáticas têm valores menores tanto para quem toma quanto para os que não tomam café comparados ao vírus C, porém os dados foram estatisticamente

Ousasse apontar algumas hipóteses para a solução desse problema público a partir do exposto dos autores usados como base para fundamentação teórica, da análise dos dados

7KH LQWHQVH VSRUXODWLRQ RI % FLQHUHD RQ GLVHDVHG HXFDO\SWXVSODQWVLVHDVLO\VSUHDGE\ZLQGDQGE\LUULJDWLRQ ZDWHU)HUUHLUD)HUUHLUD 6RX]D)HUUHLUD 0LODQL7KLVLVVLPLODUIRU