Drought Management and Planning for Water Resources - Chapter 7 ppsx

chapter seven Droughts and the European water framework directive: Implications on Spanish river basin districts Teodoro Estrela Confederación Hidrográfica del Júcar, Spain Aránzazu Fi

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chapter seven

Droughts and the European water framework directive:

Implications on Spanish river basin districts

Teodoro Estrela Confederación Hidrográfica del Júcar, Spain Aránzazu Fidalgo

Confederación Hidrográfica del Júcar, Spain Miguel Angel Pérez

Universidad Politécnica de Valencia, Spain

Contents

7.1 Introduction 170

7.2 Droughts in the WFD 170

7.3 Drought planning legal framework in Spain 171

7.4 Drought management tools 173

7.5 Drought indicators for the Spanish territory 173

7.6 The Júcar River Basin District 174

7.6.1 Recent droughts occurred in the Júcar river basin 182

7.6.2 Drought indicators in the Júcar River Basin District 182

7.6.3 The Júcar River Basin Drought Special Plan 186

7.7 Conclusion 190

References 191

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170 Drought Management and Planning for Water Resources

7.1 Introduction

The European Water Framework Directive (WFD) (2000/60/EC) establishes

a framework for community action in the field of water policy The mainobjective of the WFD is to achieve the good status of water bodies, protectingthem and impeding their deterioration This directive represents a substan-tial change in the traditional approach for water management since:

• It emphasizes water quality aspects, environmental functions, and asustainable water use, contributing to mitigate the effects of floodsand droughts

• It establishes the river basin as the basic unit for water managementincluding in its domain groundwater, transitional, and coastal waters

• It requires transparency in the access to hydrological and mental data, forcing standardization of procedures to determine theenvironmental status of water bodies

environ-• It introduces the principle of cost recovery favoring a greater publicparticipation in the whole process

The WFD is a complex directive that imposes a large number of tasks

on European Union member states The directive is organized into 53 ments, 26 articles, and 11 annexes, which is transferred to the legal system

state-of member states

A key aspect of the WFD implementation has been the creation of anetwork of European pilot river basins with the main goal to ensure thecoherence and crossed application of the guide documents elaborated byworking groups made by experts from the member states Spain assumedthe highest level of compromise by proposing verification and evaluation,

in the territorial area of the Júcar River Basin Authority (RBA), which is one

of the pilot river basins, of all guide documents and agreed to work on thedevelopment of a platform of a common Geographic Information System

In this chapter droughts are analyzed from the perspective of the WFD,placing emphasis on drought planning and management aspects and focus-ing on the case of Spain and more specifically on the Júcar RBA

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Chapter seven : Droughts and the European water framework directive 171

In Article 1 (Purpose), the purpose of the directive is specified to establish

a framework for the protection of inland surface waters, transitional waters,coastal waters, and ground water, which prevents their further deterioration,protects and enhances the status of aquatic ecosystems, promotes sustainablewater use, aims at enhance protection and improvement of the aquatic envi-ronment by promoting a progressive reduction of discharges, ensures acontinuing reduction of pollution of ground water, prevents its further pol-lution, and contributes to mitigate the effects of floods and droughts Point 6 of Article 4 (Environmental objectives) explains that temporarydeterioration of the status of water bodies shall not be in breach of the require-ments of this directive if this is the result of circumstances of natural cause orforce majeure, in particular extreme floods and prolonged droughts, when all

of the following conditions have been met : (a) all practicable steps are taken

to prevent further deterioration in status, (b) the conditions under which cumstances that are exceptional or that could not reasonably have been foreseenmay be declared, including the adoption of the appropriate indicators, are stated

cir-in the River Bascir-in Management Plan, (c) the measures to be taken under suchexceptional circumstances are included in the program of measures, and (d) asummary of the effects of the circumstances and of such measures taken or to

be taken is included in the next update of the River Basin Management Plan

In Annex 6 (Lists of measures to be included within the programmes ofmeasures) Part B the demand management measures are included, whichdescribe inter alia the promotion of adapted agricultural production, such

as low water requiring crops in areas affected by droughts

To summarize:

• Droughts constitute an exemption from some WFD requirements

• The declaration of a drought situation must be defined in the BasinManagement Plan, adopting adequate indicators

• Measures to be adopted in drought situations must be incorporated

in the Programme of Measures

• The Basin Management Plan, once updated, will summarize the fects of droughts and measures

ef-• Low water requiring crops should be applied in areas affected bydroughts

7.3 Drought planning legal framework in Spain

Drought management can be carried out by two main approaches:

1 As an emergency situation, that is considering it as a crisis situation,which can be restored with extraordinary water resources

2 As a current element of the general water planning and management,which means that a risk analysis must be carried out to assess its prob-ability of occurrence and measures to be applied must be planned ahead

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In Spain, droughts have been traditionally managed according to thefirst approach, although since the entry into force of the Hydrologic NationalPlanning Act (HNP, 2001) both approaches should be used

The Water Act foresees proper measures for strong drought situations.These measures are determined by the Spanish government and are focused

on the use of the public hydraulic domain They are submitted by theso-called Royal Decree Acts of urgent exceptional measures Public works(mainly drought wells) that result from these measures are declared of publicuse and the private property where they might be located can be expropri-ated for immediate construction

Clear examples are the urgent measures applied at the beginning of the1980s or during the years 1994 and 1995, with the building of urban supplypipes Examples of laws associated with urgent measures for drought situ-ations are:

• Act: “Ley 6/1983 de 29 de junio de 1983, sobre medidas excepcionalespara el aprovechamiento de los recursos hidráulicos escasos a con-secuencia de la prolongada sequía”

• Act: “Ley 15/1984 de 24 de mayo, para el aprovechamiento de losrecursos hidráulicos escasos a consecuencia de la prolongada sequía”

• Act: “Real Decreto-Ley 8/2000, de 4 de agosto, de adopción de didas de carácter urgente para paliar los efectos producidos por lasequía y otras adversidades climáticas”

me-The formal procedures of response to droughts should be considered in

a more integrated planning for the coming years Article 27 of Act 10/2001,July 5, of the National Hydrologic Plan (NHP) refers to drought planning,stating in point 1:

For the intercommunity basins, the Ministry of Environment, inorder to minimise the environmental, economic, and social impact

of any situations of drought, shall establish an overall system ofwater indicators that allows these situations to be predicted andacts as a general reference for Basin Organisations to formallydeclare situations of alert and temporary drought This declara-tion shall involve the implementation of the Special Plan de-scribed in the following point

Also point 2 of the same article specifies:

Basin Organisations shall draw up, in the scope of the ing Basin Hydrological Plans, and within the period of two yearsfrom this Act coming into force, special action plans in situations

correspond-of alert and temporary drought, including the rules for tion of systems and the measures to implement with relation to theuse of the public water domain The mentioned plans, subsequent

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to a report from the Water Council for each basin, shall be sent

to the Ministry of Environment for their approval

Finally, point 3 of the referred article 27 states:

The Public Administrations responsible for urban supply tems, which serve, singly or jointly, towns of 20,000 inhabitants

sys-or msys-ore, must have an Emergency Plan fsys-or drought situations.This Plan, which shall be reported by the Basin Organisation orcorresponding Water Authorities, must take into consideration therules and measures laid down by Special Plan mentioned in point 2,and must be operative within a maximum period of four years

7.4 Drought management tools

Drought situations are extreme hydrological events where water is scarce,and precipitation is at a minimal level They are characterized by havinglong duration with starting and ending periods uncertain

The anticipation in the application of mitigation measures becomes anessential tool for the reduction of socioeconomic effects of droughts; that iswhy having completed indicators systems that allow early warning of theseextreme events is essential These systems must be considered as key ele-ments in drought events management and in the strategic planning of theactions to be taken

The main tools for drought management and planning available in Spainare:

• Drought indicators for the Spanish territory

• Drought indicators for the River basin district

• The River Basin Drought Special Plan

• The Emergency Plan for public water supplies greater than 20,000inhabitants

These tools are described in the following section

7.5 Drought indicators for the Spanish territory

Currently, a Spanish Indicator System has been established in order to assessthe quantitative status of water resources in the different exploitation systemsexisting in each river basin district The Spanish Ministry of Environment hasdone this task jointly with the Centre of Studies and Experimentation of PublicWorks (CEDEX)

Different parameters have been chosen (inflows, outflows, and storage

in reservoirs, flow river gauges, precipitation, and aquifer water level) foreach exploitation system These parameters are used to assess the quantita-tive status of water resources in each system, comparing the record achieved

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in a determined period of time that has a historical and representative meanvalue Figure 7.1 shows the location of the selected control points

The comparison is expressed in terms of different percentages depending

on the adopted temporal period of analysis (one month, three accumulatedmonths, or 12 accumulated months) Figure 7.2 and Figure 7.3 respectivelyshow the percentage values of precipitation for a month and for the accu-mulated precipitation for the last three months

Maps are then drawn up with values of the corresponding indicators.These data are generated by the River Basin Authorities and are sent peri-odically to CEDEX where a common database is kept

7.6 The Júcar River Basin District

The Júcar River Basin District (Júcar RBD) is located on the eastern part ofSpain (Figure 7.4) It is made of a group of different river basins and covers

an area of 42,989 km2 From the 17 autonomous communities in the Spanishterritory, the Júcar RBD encompasses part of four of them: Valencia,Castilla-La Mancha, Aragón, and Cataluña, just including a small area fromthe latter

The population within the district is about 4,360,000 inhabitants (2001),which means that about 1 in every 10 Spaniards lives in the Júcar RBD Inaddition to this number about 1,400,000 equivalent inhabitants are added

Sistema de Indicadores Hidrológicos

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46 mm 33.6

37 mm 26.0

20 mm

28.4

21 mm 39.6

31 mm

40.4

20 mm 44.0

35 mm

48.2

28 mm 51.7

25 mm 41.2

21 mm

51.4

35 mm 38.2

21 mm 27.3

13 mm 36.1

55 mm 58.8

51 mm 57.2

49 mm

66.0

62 mm 59.1

41 mm 74.2

47 mm

71.8

54 mm 81.8

71 mm

89.0

99 mm 77.8

82 mm

84.3

101 mm 59.0

70 mm 63.0

77 mm 77.499 mm 56.3

70 mm 68.5

73 mm

60.6

69 mm 70.5

124 mm 70.4

83 mm

77.8

173 mm 58.0

98 mm 48.3

64 mm 48.3

67 mm 40.9

58 mm 52.3

179 mm 66.2

257 mm 63.9

197 mm

61.8 172mm

72.5

263 mm 64.7

197 mm

70.4

263 mm 78.4

250 mm

57.9

177 mm 70.1

236 mm

72.7

221 mm 67.6

236 mm 72.6

236 mm

73.4

213 mm 77.9

235 mm 80.7

266 mm 81.5

240 mm

72.7

210 mm

84.6 215mm

71.0

153 mm

80.1

198 mm 68.5

152 mm 69.5

156 mm 83.2

181 mm

81.9

214 mm 81.4

172 mm 87.9

159 mm

82.5 163mm 85.1

192 mm

91.0

223 mm 86.5

213 mm

91.5

219 mm 78.1

232 mm 80.5

225 mm 93.2

250 mm 65.9

203mm 63.6

169 mm

40.5

145 mm 67.1

177 mm

46.9

316 mm 34.8

213 mm 45.5 162mm 50.3

173 mm 43.1

159 mm 9.0

48 mm

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due to the tourism, primarily in the Valencia community Nevertheless, theJúcar RBD is a district of great contrast since population density ranges fromover 20,000 inhabitants per square kilometer in the metropolitan area of thecity of Valencia at the coast, to less than two inhabitants per square kilometer

in the mountainous areas of the province of Cuenca at the western part ofthe district

The area has a Mediterranean climate, with an average annual tion of 504 mm (MIMAM, 2000b), varying from 250 mm in the south to about

precipita-800 mm in the north of the area (Figure 7.5) This situation necessitates definingdifferent levels of regional vulnerability to droughts The precipitation overthe basin produces a mean annual runoff of 80 mm, which represents approx-imately 16% of the precipitation Renewable water resources are about 3400

hm3/year (MIMAM, 2000b)

The amount of 504 mm/year corresponds to a volume of 21,220 hm3/year over the land surface of the territory About 85% of this precipitation isconsumed through evaporation and transpiration by the soil-vegetationcomplex The remaining 15% comprises the annual runoff of 3250 hm3 / year

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according to their behavior, with the most important being the humid periods

of 1958–1977 and 1986–1990, and the driest periods of 1978–1985, 1991–1995,and 1997–2000 as is shown in the deviation graph in Figure 7.8

The Júcar RBD is characterized by long drought periods, in some casesreaching even 10 years An index that reflects the annual deviation from themean annual rainfall is the Standard Precipitation Index (SPI), shown in

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Figure 7.9, which is a normalized index used for quantifying deficits in thevolume of precipitation for any given period of time

The spatial deviation maps for the years corresponding to the 1977–1986and 1991–1995 drought periods are shown in Figure 7.10 These maps repre-sent, for each year, the percentage of variation of the annual precipitation withrespect to the mean annual values corresponding to the period 1940–2000 Thebars in Figure 7.9 show the highest percentage variation from the period meanvalue (1940–2000), which indicates that those are the driest years for the rep-resented drought period

Within the Júcar River Basin District the water resources used come fromsuperficial and ground water origins Superficial water resources have beenused historically since Roman and Arab times Nowadays, these resourcesare being regulated through large dams (Figure 7.11) The reservoir capacityfor the whole basin is of 3300 hm3; of high importance are the reservoirs ofAlarcón, Contreras, and Tous in the Júcar river, and Benageber in the Turiariver The resources coming from ground water, with a value of 2500 hm3/year,represent slightly more than 70% of the total resources used, which reflectsthe importance of this type of resource in the basin (MIMAM, 2000b).The joint use of surface water and ground water is quite common withinthe basin, with clear examples being the Plana of Castellón, La Marina Baja,

or the Ribera of the Júcar However, the intensive use of ground water hasproduced overexploitation problems in some of the hydrogeological units,such as the ones of the exploitation system Vinalopó-Alacantí, the ones fromcoastal plateaus of the province of Castellón, or the hydrogeological unit ofthe Mancha Oriental aquifer

Regarding the reuse of nonconventional resources, it is important tomention the high potential of reuse (treated wastewaters), which represents

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