As the Water Demand Projections Are Based on an Integrated Analysis That Includes Social

TABLE OF CONTENTS3. SOCIO-ECONOMIC DATA BASIS AND DEVELOPMENT OF SCENARIOS………………… 443.1. Methodology and Data Compilation………………………………………………………. 443.2. Scenario Development………………………………………………………………………483.2.1. General……………………………………………………………………………..48 3.2.2. Scenarios Developed for the Gediz Basin Case Study……………………….493.3. References for Section III……………………………………………………………………524. LUC DYNAMIC LAND USE CHANGE MODEL STUDIES...... 584.1. General...... 584.2. Land Use Classification...... 594.3. Major Land Use in the Coastal Area (Izmir Bay)...... 604.4. Agricultural Land Use in the Gediz Basin...... 624.5. Conclusion...... 65 3. SOCIO-ECONOMIC DATA BASIS AND DEVELOPMENT OF SCENARIOS3.1. Methodology and Data CompilationWater demand projections required by SMART are based on an integrated analysis including social, economic, and institutional perspectives. Accordingly, socio-economic data for the Gediz Basin are compiled to contribute to the socio-economic analysis in WP02 and to underlie the scenario development and comparative analysis in WP10.As specified in Project Deliverable D02.2 “Guidelines for the Socio-Economic Analysis: Issues and Indicators” by UATLA, there are four tasks identified in WP02:1) Population, demographic and migration policy analysis, 2) Political and economic options adopted for the study areas, 3) Competing water uses, 4) Economic analysis of water resources.In Task 1, population dynamics are identified on the basis of demographic parameters and projections, such as those related to birth, death, migration, and their trends in the past. In particular, migration policies are analyzed, and it is observed that a limiting migration policy has different effects on population growth from those imposed by a free migration policy. For the Gediz Basin, socio-economic data are collected and processed to derive the indicators presented in Table 3.1 .Table 3.1. Indicators and Data Needs for Task-1 of WP 02.UNITS in which INDICATORS the indicator is DATA NEEDS expressed Task 1 Population, Population growth rate % of growth Resident population demographic Immigration and Migratory balance Number of people migration Emigration policy Number of Resident population analysis Population Density people/municipalit y area (km²) Municipality area Number of Resident population Number of persons by persons by household household Households Resident population Crude Death Rate %o Number of deaths Resident population Crude Birth Rate %o Number of live births Female population by age Synthetic general fertility Number of groups index children by mother Number of live births Life expectancy at birth Number of years Life expectancy at birth44 Some indicator values for Task-1 are computed on the basis of available data such as; growth rates, yearly growth rate, population density, and the rate of the net immigration. It was possible to obtain population data for each district throughout the basin; however, the other required data were available only on a regional and/or national basis. In Appendix II, Tables A2.1 to A2.5 present the collected and calculated data for Task-1.of the Gediz Basin case study. The aim of Task-2 is to analyze the institutional structure of water quantity and quality management in the basin; thus, planning and management policies, instruments and their levels in the region are studied to include also the level and pattern of economic growth. It is therefore intended in Task-2 to analyze basic policies and options for economic growth that lie at the origin of competing uses of water. The consequences in terms of labor demand are also important issues to understand the changes in regional dynamics and expected developments. Data for Task-2 are compiled on the basis of specified indicators, as presented in Table 3.2. The available data for the Gediz case study are given in Appendix II on Tables A2.6 to A2.9.Table 3.2. Indicators and Data Needs for Task-2 of WP 02.UNITS in which INDICATORS the indicator is DATA NEEDS expressed Growth of G.D.P. (Gross G.D.P. (Gross Domestic Domestic Product) at market % Product) at market prices prices Resident population Activity rate % Number of persons with an Task 2 economic activity Agricultural income Agricultural income Political and distribution by the main € distribution by the main types Economic types of production of production Options Adopted for Industrial income distribution Income distribution by main the Study by main industrial activity € industrial activity groups Areas groupsPercentage of tertiary % Employment in tertiary sector employmentTourism income contribution Tourism income € to the regional product Regional productNo data are collected for the last indicator on tourism income since tourism activities do not have a significant contribution to the economy of the basin. Analysis of the various stakeholders and their interests, along with the identification of water demands, are performed within the scope of Task-3. The economic and demographic structures of45 the rural/urban interface are investigated in terms of their consequences for multisectoral current and projected water demand, and the implied conflicts. Data for this task are collected according to the identified needs given in Table 3.3, and the compiled data are presented in Table 3.4.Table 3.3. Indicators and Data Needs for Task-3 of WP 02.UNITS in which the INDICATORS indicator DATA NEEDS is expressed Resident population Water consumption per capita liters/day Total water consumedResident populationDomestic consumption of liters/ca- water consumed per person for the Task 3 water per capita day purposes of ingestion, hygiene, cooking, Competin washing of utensils and other household g Water purposes Uses Commercial water liters/day water consumed per commercial activity consumptionIndustrial water consumption liters/day water consumed per industrial unit per unitTotal water consumption m3 Total water consumedTable 3.4. Water Consumption in the Gediz Basin.WATER SOURCE INDICATOR CONSUMPTION500 liters/ ca- State Hydraulic Works, DSI; Department of Water consumption per capita day Water Works of municipalitiesDomestic consumption of State Hydraulic Works, DSI; Department of 150 liters/ca-day water per capita Water Works of municipalities 300 liters/ ca- State Hydraulic Works, DSI; Department of Commercial water day Water Works of municipalities; Irrigation consumption including Associations agricultural useState Hydraulic Works, DSI; Department of Industrial water consumption 50 liters/ ca-day Water Works of municipalities; individual per unit industries and organized industrial districts46 State Hydraulic Works, DSI; Department of Water Works of municipalities; individual Total water consumption 700 000 000 m3 industries and organized industrial districts; irrigation associationsIn the scope of Task-4, the costs of water supply are included in the analyses, considering the possible differences between costs of domestic water, irrigation water, industrial and other needs (e.g. aquaculture). Data requirements for this task are specified in the project Deliverable D02.2 as those given in Table 3.5. The case study data are presented in Table 3.6.Table 3.5. Indicators and Data Needs for Task-4 of WP 02.UNITS in which INDICATORS the indicator is DATA NEEDS expressedWater price for the domestic €/m3 Water price for the domestic use useWater price for the €/m3 Water price for the Agriculture AgricultureTask 4 Economic 3 Analysis of Water price for the Industry €/m Water price for the Industry Water Resources Water price for the Tourism € Water price for the Tourism units units Water treatment - Water treatment investments investments Reservoir storage - Reservoir storage investments investments Water distribution and use Water distribution and use systems - systems investments investmentsData related to the indicators identified in all these four tasks were compiled as much detailed as possible, but still some problems were encountered, as described in the following.In Task-1, some data such as life expectancy at birth were not available at municipal or regional scales. Furthermore, for some indicators, like the crude death rate, data were not available for the previous years to facilitate “change in time” comparisons.In Task-2, no data were available on growth of GDP at regional or municipal scales. In addition, data for the years 1994 and 1998 were compiled instead of 1990 and 2000, respectively, due to the unavailability of the latter. For industrial income distribution, again there were no available data.47 In Task-3, it is noted that domestic water consumption is different in each of the 36 municipalities in the Gediz Basin due to varying life-styles. Furthermore, there were no available data for water consumption in the previous years. Another problem encountered was the lack of sufficient information on groundwater use. In general, data on groundwater use are not recorded but roughly estimated. Similarly, water consumption in commercial and industrial units is not known; hence, it is estimated roughly on the basis of per capita values, regarding the total water budget along the basin.Table 3.6. Water Prices for Consumptive Water Use in the Gediz Basin.INDICATOR WATER PRICE SOURCEState Hydraulic Works, DSI; Water price for the domestic use 0.4 €/m3 Department of Water Works of municipalitiesState Hydraulic Works, DSI; Water price for the Agriculture 0.01 €/m3 Department of Water Works of municipalities; irrigation associationsState Hydraulic Works, DSI; Water price for the Industry 0.90 €/m3 Department of Water Works of municipalities no significant Water price for the Tourism - contribution to units income Water treatment investments no data available -Reservoir storage investments no new investment - Water distribution and use no data available - systems investmentsIn accomplishing Task-4, the difficulty was the presence of too many municipalities, each with a different rate of domestic water consumption. On the other hand, costs of agricultural water consumption are not fixed; irrigation water is allocated by DSI for free, but Irrigation User Associations decide upon the fees, regarding maintenance, operation and management costs in the irrigation schemes. Industrial units receiving water from municipal water distribution schemes pay approximately 0.90 €/m3, but no cost is defined for groundwater use. In Gediz, new investments on reservoir storage are not planned except for the two reservoirs which are currently under construction. Furthermore, no data are available on investments for treatment and water distribution schemes.3.2. Scenario Development3.2.1. GeneralIn the scope of SMART, three dimensions, namely economical, social and environmental, are considered as pillars of sustainability, and it is emphasized that sustainability lies in the cross- section of these three dimensions.48 Accordingly, a significant part of efforts identified for SMART is devoted to the development and comparison of management scenarios for the selected case study areas, regarding sustainability criteria. Three types of scenarios are considered after determining the current status of the study areas as:- Business as usual (BAU), - Optimistic (OPT), and - Pessimistic (PESS).The Business As Usual Scenario assumes the continuation of existing trends and depends on the current dynamics of the study area. The Optimistic Scenario foresees improvement in the existing policies and trends and focuses on the environment. On the other hand, in the Pessimistic Scenario, it is assumed that population trends may increase the pressure over water use and that there is an aggravation of existing policies and trends that may have harmful effects over water.Each scenario is designed on the basis of the “Water Demand Framework” as shown in Figure 3.1. For each scenario, sustainability indicators are determined, and then all scenarios are compared to each other. Figure 3.1. Framework for Water Demand Projections.3.2.2. Scenarios Developed for the Gediz Basin Case StudyIn the Gediz Basin, domestic, agricultural and industrial water demands constitute the main types of water consumption along the entire basin. Nearly 100 % of available water is consumed by these three sectors. While domestic and industrial water demands are met by groundwater resources, almost 75 % of surface waters is utilized by irrigation schemes (Cetinkaya et.al.,2004).Domestic water demand has increased within the past years because of high immigration rates from rural to urban areas. Immigration has also resulted in rapid development in urban areas so that most of the infrastructural investments have become insufficient.Increases in industrial water demand depend mainly on the accelerated growth in industrial areas, especially in Manisa and Kemalpasa districts. Water needs of the industry are met by groundwater, but no records of consumption are available. The increase in agricultural water demand is caused by high losses in the existing irrigation schemes and to a certain degree, by changes in crop patterns.The driving forces considered for increases in these three main types of water consumption are summarized in Fig 3.2 (Cetinkaya et.al.,2004). For baseline conditions, the variables which describe the current driving forces are given in Table 3.7. 49 50 Immigration from Rural Population Over Exploitation of Change in Crop Insufficient M&O* to Urban Areas Growth Groundwater for Pattern Irrigation No new Investment for Increase in Urban Increase in Irrigation Water Population Irrigated Area Conveyance Basin-out Water Systems Ttransfer Increase in Irrigation Water No new Insufficient Pricing Investment for Financial Status Low Precipitation Better Irrigation for Domestic Methods Water Supply Infrastructure Investments Groundwater Pollution High Irrigation Water Increase in Industrial Loss Ground & Surface Water Use Surface Water PollutionINCREASE IN INCREASE IN INCREASE IN DOMESTIC WATER INDUSTRIAL WATER IRRIGATION WATER DEMAND DEMAND DEMANDINSUFFICIENT WATER SUPPLYFigure 3.2 Driving forces leading to insufficient water supply (*: Maintenance and Operation).51 Table 3.7. Existing (baseline) conditions in the Gediz Basin.Variables/driving forces Baseline Birth control existing Urban growth rate 923 000 Rural growth rate 704 000 Precipitation rate 700 mm/y Groundwater supply 9 mm/y Surface water supply 59 mm/y Groundwater pollution Class IV Basin-out water transfer (surface & 0.2 mm/y groundwater) Domestic water use (groundwater) 7.4 mm/y Industrial water use (groundwater) 3 mm/y Irrigation water use 39 mm/y Domestic water supply investments sufficient Change in crop pattern Cotton, grape, maize Irrigation m/o* investments insufficient Loss rate in irrigation system 30 % Irrigated area 1070 km2 Industrial water use (surface water) 0 mm Class IV Surface water quality (highly polluted according to the Turkish Water Quality Standards Water exploitation awareness Insufficient awareness *: Maintenance and OperationThe baseline variables/driving forces are considered for development of three scenarios; business as usual (BAU), optimistic and pessimistic, for which the following assumptions are made (Cetinkaya et.al., 2004); There is an existing and successful birth control policy in Turkey. In scenario development, birth control is taken into consideration for BAU and optimistic scenarios. In rural areas of eastern Turkey, birth control is not fully successful; hence, such a situation is also developed into a pessimistic scenario.  The high immigration rate from rural to urban areas is reflected in the pessimistic scenario as an increased urban population growth rate. For the optimistic scenario, birth and death rates are balanced in urban areas where only immigration is considered since there has been a descending trend in the rural population over the last ten years.  Decreases in the average precipitation rate are considered only in the pessimistic scenario, regarding the historical drought periods that lasted more than 6 years with a decrease of 40% in precipitation.  Both the groundwater and the surface water supplies are considered in the pessimistic scenario as they both decrease when precipitation decreases.52  Water is transferred out of basin to meet Izmir municipality’s domestic water needs; furthermore, there is an on-going project (Gordes reservoir), which will also supply domestic water to the city of Izmir.  Increases in domestic water use are foreseen for both the optimistic and the pessimistic scenarios due to expected increases in immigration and improving life standards.  Irrigation water use is expected to decrease with a possible adoption of better irrigation methods in the optimistic scenario; in the pessimistic scenario, an increase is foreseen due to worse management policies, crop pattern changes, and insufficient public awareness.  In the optimistic scenario, irrigation water loss rate decreases due to development of better conveyance systems and sufficient maintenance.  No change in irrigated area is expected, as urban areas are growing.  There is a dam under construction, which will supply industrial water; hence surface water is also expected to meet increasing industrial water demand.Scenarios developed for the Gediz Basin on the basis of the above considerations are presented in Table 3.8.In the project Deliverable D04.1 on Data Compilation and Analysis, prepared by SUMER, the indicators and responses for the developed scenarios are compiled in the database for each case study case. Tables 3.9 through 3.12 represent that part of the database which corresponds to the Gediz case study. These tables are designed to facilitate the comparative analyses among the case studies as required by WP 10 of SMART.3.3. References for Section IIICETINKAYA, C.P.; BARBAROS, F.; GUNDOGDU, H. (2004): “Determination of Social and Economical Indicators for Future Wateruse Scenarios in Gediz River Basin”, EWRA Symposium on: Water Resources Management: Risks and Challenges for the 21st Century, Izmir, Proceedings Volume I, pp. 375-383.53 Table 3.8. Scenarios Developed for the Gediz Basin. Variables/driving forces Baseline BAU Optimistic Pessimistic Existing Existing Existing Birth control existing (partially (successful) (unsuccessful) successful) Urban growth rate 923 000 1.5 %/y 1 %/y 3 %/y Rural growth rate 704 000 - 1 % /y -1 % /y -2 % /y Precipitation rate 700 mm/y 0 % 0% -10% Groundwater supply 9 mm/y 0 % 0 % -10% Surface water supply 59 mm/y 0 % 0 % -10% Groundwater pollution Class IV Class IV Class III Class IV Basin-out water supply 0.2 mm/y 0.2 mm/y 0.4 mm/y 0.5 mm/y (surface & groundwater) Domestic water use (surface & 7.4 mm/y 0% 0.5 %/y 2.5 %/y groundwater) Industrial water use 3 mm/y 0% 4%/y 8%/y (groundwater) Irrigation water use 39 mm/y 0%/y - 40% 15% Domestic water supply sufficient sufficient sufficient insufficient investments Cotton, Cotton, grape, Grape, vegetable, Change in crop pattern grape, Cotton, grape maize maize maize Irrigation m/o investments insufficient insufficient Sufficient insufficient Loss rate in irrigation system 30 % 30 % 10% 30% Irrigated area 1070 km2 0% 0% 0% Industrial water use (surface 0 mm 0 mm 4 mm 4 mm water) Surface water quality Class IV Class IV Class III Class IV Insufficient Insufficient Comprehensive Insufficient Water exploitation awareness awareness awareness awareness awareness54 Table 3.9. Indicator values of the Turkish case study.Ind_Code Indicator Unit BASELINE BAU OPT PES Urban (Number of People) 923 000 Regional Population Rural (Number of People) 704 000 TOTAL (Number of People) 1 627 000 C1 Average Precipitation mm/y 700 C2 Precipitation Increase/Decrease % 0 0 -10 C3 Daily Average Temperature 0C 15.6 15.6 15.6 16.6 D1 Population Growth Rate %o/year 0.6 0.25 1.5 D2 Migratory Rate %/year 4 4 D3 Population Density Number of People / km2 112 112 103 140 D4 Crude Death Rate %o/year 1.14 1.14 D5 Crude Birth Date %o/year 9 9 D6 Life Expectancy at Birth years 2 for successful D7 Birth Control Efficiency 1 for partially successful 1 1 2 0 0 for unsuccessful D8 Urban Growth Rate %/year 0.15 0.15 0.1 0.3 D9 Rural Growth Rate %/year -0.1 -0.1 -0.1 -0.2 E1 Growth of G.D.P. % E2 Activity Rate % 25 25 E5 Percentage of Tertiary Employment % 36 36 E6 Tourism Income Contribution to the Reg. Product EURO/year THESE VALUES ARE NOT NECESSARY FOR THE DESCRIBED INDICATORS INDICATOR VALUES THAT MUST BE PROVIDED FOR FUTURE REQUIREMENTS THERE IS NO TOURISM ACTIVITY IN THE REGION55 Table 3.10. Indicator values of the Turkish Case Study (continued).Ind_Code Indicator Unit BASELINE BAU OPT PES P1 Water Price for the Domestic Use EURO/M3 0.4 0.4 P2 Water Price for the Agriculture Use EURO/M3 0.01 0.01 P3 Water Price for the Industry EURO/M3 0.9 0.9 P4 Water Price for the Tourism Units EURO/M3 W1 Domestic Water Consumption (daily average) m3/sec 3.94 3.94 4.46 7.3 W2 Commercial Water Consumption (daily average) m3/sec 0 0 0 0 W3 Agricultural Water Consumption (daily average) m3/sec 20.75 20.75 12.45 23.86 W4 Industrial Water Consumption (daily average) m3/sec 1.6 1.6 4.27 10.96 W5 Environmental Water Demand (daily average) m3/sec 0.2 0.2 0.2 0.25 W6 Water Consumption by Tourism (daily average) m3/sec 0 0 0 0 W7 Total Water Consumption (daily average) m3/sec 26.49 26.49 21.38 42.37 W8 Irrigated Area km2 1070 1070 1070 1070 0 for insufficient awareness W9 Water Exploitation Awareness 0 0 1 0 1 for comprehensive awareness THESE VALUES ARE NOT NECESSARY FOR THE DESCRIBED INDICATORS INDICATOR VALUES THAT MUST BE PROVIDED EITHER AS REAL OR ANTICIPATED VALUES INDICATOR VALUES THAT MUST BE PROVIDED FOR FUTURE REQUIREMENTS THERE IS NO TOURISM ACTIVITY IN THE REGION56 Table 3.11. Response values of the Turkish case study.Resp_Code Response UNIT CURRENT FUTURE WDM1 Water price (domestic) EURO/m3 0.4 WDM2 Water price (agriculture) EURO/m3 0.01 WDM3 Water price (industry) EURO/m3 0.9 WDM4 Water price (tourism) EURO/m3 WDM5 Water subvention (domestic) EURO/m3 0 WDM6 Water subvention (agriculture) EURO/m3 0.5 WDM7 Water subvention (industry) EURO/m3 0 WDM8 Water subvention (tourism) EURO/m3 0 1 for "flooding" WDM9 Irrigation system 2 for "sprinkling" 3 for "dripping" 1 0 for "low" WDM10 Awareness for limiting uncontrolled abstraction 1 for "partial" 2 for "high" 1 WQM1 Share of industrial wastewater treated on site % 0 for " ineffective " WQM2 Solid waste management 1 for "effective" 0 WQM3 Urban waste water treatment m3/year 0 for "local" WQM4 Water treatment investments 1 for "extensive" 0 0 for "low" WQM5 Awareness for limiting fertilization 1 for "high" 0 WQM6 Share of collected and treated wastewater % 0 RESPONSE VALUES THAT MUST BE PROVIDED FOR FUTURE REQUIREMENTS57 Table 3.12. Response values of the Turkish Case Study (continued). Resp_Code Response UNIT CURRENT FUTURE 0 for "low" WQM7 Limiting salinization through drainage systems 1 for "high" 0 0 for "insufficient" WQM8 Existence of pollutant monitoring programs 1 for "full" control 0 0 for "insufficient" WQM9 National regulations on wastewater 1 for "full" control 0 0 for "incomplete" WSM1 DomesticWater Distribution&Use Systems Investments 1 for "complete" 1 0 for "incomplete" WSM2 Agri. Water Distribution&Use Systems Investments 1 for "complete" 0 0 for "low" WSM3 Reservoir Storage Investments 1 for "high" 0 WSM4 Efficiency in irrigation % 65 WSM5 Efficiency in urban network % 70 WSM6 Minimum flow for environmental purposes m3/sec 0.01 WSM7 Water harvesting m3/yr 0 for "insufficient" WSM8 Groundwater exploitation control 1 for "full" 1 WSM9 Mobilization of surface water m3/year WSM10 Water Export (Surface&Groundwater) % 21 WSM11 Water import % WSM12 Recycling of wastewater % WSM13 Desalination % WSM14 Limits to groundwater exploitation 58 RESPONSE VALUES THAT MUST BE PROVIDED FOR FUTURE REQUIREMENTS59 4. LUC DYNAMİC LAND USE CHANGE MODEL STUDİES4.1. GeneralLand use is a major driving force for water demand, which is also a constraint on land use change options in the Gediz Basin. LUC model calculates the dynamic development (annual time step) of land use over decades and estimates regional water use as a function of land use. This estimate is intended as a rough check on the much more detailed WaterWare water budget, but with a long- term perspective and change over decades. The major purpose of the LUC model application in the Gediz Basin is to estimate regional water budgets and related indicators as a consistency check for WaterWare inputs.On the other hand, a set of well defined land use classes are needed in order to operate the LUC model; whereas, well defined land use classification data do not yet exist for the Gediz Basin. Former studies on this matter are quite inadequate, and their results conflict with each other.The most recent land cover (LC) information (Figure 4.1), which is assumed to be the most appropriate one to be used in the SMART project, is the land cover information determined by the General Directorate of Rural Services (GDRS) in the scope of an International Water Management Institute (IWMI) funded project in 2000. This LC information was obtained via satellite images of 1990.Figure 4.1. Land Cover information as of 1990 (GDRS).The second land cover information comprises the data set obtained from the global land cover characteristic database of the U.S. Geological Survey's EROS Data Center (EDC), which was constructed by using satellite images taken from 1981 to 1994. This land cover information is given in Figure 4.2.Figure 4.2. Land Cover information based on 1981-1994 data of USGS.The third source of information is the Turkish State Statistical Institute (TSSI) land cover data for Turkey, which was constructed by using satellite images taken from 1987-1990 (Figure 4.3).60 Figure 4.3. Land Cover information based on 1987-1990 data of TSSI.As it can be observed on Figures 4.1, 4.2, and 4.3, the land cover information derived from different sources is quite different from one another; furthermore, land cover classes of the three figures are also different.In the SMART project, LUC model uses the basic set of CORINE Level 2 land use classes, which were initially assumed in the project proposal to be available for the case study area or assumed to be convertible from other existing land use maps. However, as discussed above, land use maps obtained throughout the project duration (Figs. 4.1, 4.2, and 4.3) are not consistent and not convertible to CORINE Level 2 Classes as much as desired.Thus, at the beginning of the project, it was decided not to apply LUC to the Gediz Basin since detailed and CORINE compatible land use information was not available for the study area. However, before the Tunis meeting (September 2004), two Landsat images (TM and ETM+), which were taken in June 1987 and June 2000, were obtained from Global Land Cover Facilities in USA, and it was then decided to evaluate them to achieve at least some information rather than being settled with no information.Yet, the above-mentioned two images were not found to be sufficient for building up of land use maps, which require several images and processing efforts. Despite this insufficiency, it was decided to determine only the major land use classes to achieve reasonable water demand figures for the case study area on the basis of land use patterns, and to compare the land use changes between the case studies of SMART. These efforts included first the “image processing” phase and then the “classification” phase. As the image processing phase takes a lot of time and the classification phase requires much more than two remotely sensed images of the case study area in different time resolutions, the LUC model is merely evaluated as a tool to compare two land use maps of different dates (two Landsat images) and of rough land classifications.4.2. Land Use ClassificationSince the case study area (Gediz River Basin) has a very large coverage, it is not possible to achieve fairly detailed CORINE land use classes by processing only two images mentioned above. For example, it is not possible, by image processing, to distinguish urban fabric areas from commercial areas and, similarly, barren areas from agricultural areas after harvest time. Such a study requires several in-situ observations (for supervised classification) and several images taken at different time periods. The in-situ observations are available only for the city of Izmir, which lies along the coastal zone of the Gediz River Basin. For the whole basin, the two available satellite images can only be used for identifying simplified but major land use patterns. Therefore, the land use change model of the SMART project is applied only on two sections of the Gediz basin. The first one is the coastal area where CORINE classification can be used. This section focuses only on the Bay of Izmir and its surroundings, which represent the expansion of the metropolitan area in61 the case study area. The second section is the inland basin where the main water user is agriculture.. Thus, this section is focused only on the agricultural areas and forest areas where forest maps as in-situ information are available.4.3. Major Land Use in the Coastal Area (Izmir Bay)The city of Izmir has had a long-standing claim on groundwater resources within the Gediz basin. There are two main well fields, at Sarıkız in the north of the basin and Goksu near Manisa. Actual consumption data are not available, but Izmir has extracted as much as 108 million m 3/year from these well fields. Because the water is transferred out of the basin, there is no return flow. In the near future, Izmir will also use the surface waters of Gediz basin by means of Gördes Dam reservoir, which is still under construction. This consumption of water is considered in one of the future scenarios of WaterWare as 65 million m3/year.Figures 4.4 and 4.5 show the composite images of Izmir and its environs, obtained from satellite images taken in June 1987, and the major land use classes obtained from that image, respectively. Figure 4.5 is a clustered image which is obtained from the original satellite image by band anaysis. This figure shows the major groups of reflectance combinations which are a kind of raw land cover classes.Industria AreaCoastal WetlandMine Fields1987 UrbanForestFigure 4.4. Composite image of Izmir and its environs (June 1987).Figure 4.5. Main land cover classes of Izmir and its environs (June 1987).62 Figure 4.6 shows the composite image of Izmir and its environs, obtained from satellite images taken in the year June 2000. The growth of the urban, industrial, and mine fields can be easily observed by comparing this figure to Figure 4.4. Figure 4.7 shows the main land cover classes obtained from the satellite image of June 2000.Industria AreaCoastal WetlandMine Fields2000 UrbanForestFigure 4.6. Composite image of Izmir and its environs as of 2000.Figure 4.7. Main land cover classes of Izmir and its environs as of 2000.Land cover information does not always show the land use properties of an area. Land use classes relate to the classification of an area on the basis of classified human activities. For example, although urban fabric and forest land cover information can easily be distinguished by image analyses, land based or in-situ information is required to determine the proportion of settlements and/or commercial areas in an urban fabric area.After the image processing phase of this study, the clustered images (Fig. 4.5 and 4.7) are classified by considering the in-situ information of land use in the Izmir city on the basis of CORINE classes. As a result, CORINE classified land use map of Izmir and its surroundings are determined, as given in Figures 4.8 and 4.9 for the years 1987 and 2000, respectively.63 Comparison of two land use figures of different dates show that the Urban Fabric, Industrial and Forest areas have grown roughly 70%, 28% and 25%, respectively, in 13 years. On the other hand, Shrubs, Permanent Cropland and Wetland areas have decreased nearly 95%, 45% and 27%, respectively, within the same period. The population figures of the metropolitan areas identify the population growth rate approximately as 2.6%, which indicates a 40% increase in population within 13 years. These figures support the land use change rates of the urban fabric areas. The increasing water demand of Izmir is now to be supplied by the Gördes Dam reservoir on Gediz.Figure 4.8. Generalized CORINE land use classes of the Izmir Bay and its surroundings in 1987.Figure 4.9. Generalized CORINE land use classes of the Izmir Bay and its surroundings in 2000.4.4. Agricultural Land Use in the Gediz BasinThe Gediz Basin contains a typical range of water users, although the balance among them has been changing during the past couple of decades. Traditionally, the largest user of water has been irrigated agriculture, originally deriving water from small run-of-the-river diversions from the Gediz and its tributaries, dating back some three thousand years. Since 1945, the developments of large- scale systems and groundwater exploitation have transformed the characteristics of irrigated agriculture.The first investments in modern irrigated agriculture began in 1945 with the construction of two large regulators to tap the flow of the Gediz River. Adala regulator serves some 20,000 hectares of land in the middle portion of the basin, while Emiralem regulator commands 22,000 hectares in the Gediz delta (Figure 4.10). In the 1960s, a second set of investments were made, that included the64 construction of Demirköprü Reservoir a few kilometers upstream of Adala, a third regulator at Ahmetli, and the regulation and rising of the natural lake of Göl Marmara. Ahmetli Regulator commands some 45,000 hectares of land. The final surface water developments took place in the Alasehir valley with the construction of two small reservoirs which command 15,000 ha of agricultural area. With the addition of these dams, almost the whole irrigation system, including major irrigation reservoirs and the conveyance systems, is completed in the basin.Figure 4.10. Irrigation and drainage flow patterns in the Gediz basin.The total command area of the large-scale surface systems is approximately 110,000 ha, which is also supported by the image processing phase. The predominant crops are cotton (50%), grapes (35%), maize, fruit orchards, and vegetables. At present, the surface water issued from Demirkopru is limited to the interval between mid-June and mid-September, which essentially corresponds to the cotton-growing season. Natural streamflows from tributaries can be used for land preparation for cotton or for early irrigation of grapes and fruit trees, but there are no releases to the Gediz River from Demirkopru beyond the indicated period. Water use in the 90,000 hectares of the central and delta zones is limited to 75 m3/sec from Demirkopru and 15 m3/sec from Goll Marmara for a release period of approximately 60 days, or a total of some 550 million cubic meters during the year. This is equivalent to some 450 mm of irrigation water for the growing season. In the Alasehir Valley in the eastern part of the basin, irrigation is almost exclusively realized for grapes. Application rates are approximately 350 mm/season, and during the summer, there is no significant net outflow into the main part of the basin. It is estimated that, through a combination of surface irrigation and some pumping of the shallow aquifer, approximately 60 million m3 are consumed during the summer season for irrigation.In many tributary valleys of the basin, there are small-scale surface water diversions that take advantage of winter runoff and spring snowmelt. Typical crops are fruit trees, winter wheat, and vegetables because these require water only in the spring and early summer before the streams dry out. There are no accurate records of the total area involved, but it almost certainly is more than 25,000 hectares since almost every village situated on the valley fringe has some irrigated area. However, in these areas, total water use is low and is estimated to be around 50 million m3.The basin portion of the Land Use Change model is constituted from almost the entire Gediz basin. As mentioned above, there is no extensive in-situ land use information for the basin except for the agricultural areas. Thus, the classification process is carried out only on the main agricultural areas and forest areas, which are roughly known from the formerly produced paper maps.65 Figures 4.11 and 4.12 show the distribution of the main land cover classifications of the basin in 1987 and 2000, respectively. The agricultural areas can be observed on these figures as color code 2 and 3, while the forest areas have the color codes 9 and 10.Figure 4.11. The distribution of the main land cover classification for the Gediz Basin in 1987.Figure 4.12. The distribution of the main land cover classification of the Gediz Basin in 2000.Comparison between the two land cover figures of different dates show that the areas where agricultural activity exists are decreased 15% in 13 years, while barren areas are increased 35%. Forest areas have decreased %20 in 13 years. Agricultural areas are decreasing due to the migration of rural people to the developed cities or towns, leaving their farms empty.66 4.5. ConclusionHistorical records of the stream flow data and rainfall observations over the entire basin indicate a serious drought starting from the early 1990’s. The drought had an impact not only on the releases made from Demirkopru reservoir but also on water demands. Rice, which was used to be grown in poorly drained central parts of the basin, has then been replaced by cotton, while there has been a steady increase in grape and fruit tree areas as agro-industrial enterprises have grown up to support cash crop agriculture. The trend toward grape cultivation, although partly a response to the growing market for raisins, resulted in decreased demand for irrigation water, and total irrigation deliveries are now only about 70 percent of the pre-drought situation. With a recent surge in interest in drip irrigation by fruit, vegetable and seed corn growers, demand is likely to continue to decline. In contrast, nonagricultural demand is growing rapidly. The area has a higher than average growth rate because of in- migration from poorer parts of Turkey, and Izmir has promoted industrial development to complement agricultural production. Domestic demand for water has been growing by approximately 2-3 percent a year, industrial demand by as much as 10 percent per year. Given that most nonagricultural consumption of water is from groundwater rather than surface water, aquifer management requires closer attention than surface water with respect to available volumes.67

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