PROJECT DESCRIPTION 3.1. WATER SUPPLY SYSTEM REHABILITATION PROJECTS

3.1.2. Alter Project

This project was prepared by ALTER Engineering Ltd. in 1992-1994 to study and evaluate the existing water supply network that provides drinking water to the entire city. The following data were considered for the project.

Projection year = 2027

Projection population (center) = 543,000 inhabitants

Projection population (province) = 700,000 inhabitants

Specific per capita domestic water consumption q = 275 l/cap/day

Water loss rate during project design phase (between 1992-1994) = 44 %

Lowest elevation of the project area in the existing map= 250 m (above sea level - ASL)

Highest elevation of the project area in the existing map = 665 m

Elevation difference = 415 m

Lowest elevation of the project area in contiguous area = 210 m

Highest elevation of the project area in contiguous area= 700 m

Elevation difference = 490m
Based on these elevations, the city has been divided into 6 pressure zones within the scope of the Alter project. The following water resources have been determined to supply these 6 zones:
Gokpinar Spring: The Gokpinar Spring is located in the southern part of the city and is 30 km away from Denizli. The capacity of the source is 773 l/s or 19,500,000 m³/year (with 80% efficiency). The elevation of the spring is 573 m. The planned flow rate to be taken from the source is designed to be 600 l/s. Gokpinar transmission line is designed as gravity system and have a total capacity of 1300 lt/s. It is made of 1000 mm steel pipe.
Derindere Spring: The Derindere Spring is located in the southern part of the city and is 1.5 km away from Gokpinar. It is flow rate is quite variable but has been taken 328 l/s or 8,2750,000 m³/year (with 80% efficiency) according to feasibility report. The elevation of the spring is 615 m. The planned flow rate to be taken from the source is designed to be 100 l/s. Derindere transmission line is designed to have a total capacity of 372 l/s and is planned to be made of 500 mm steel and asbestos cement pipe.
Deep wells: A total of 16 wells are located in the various parts of the city with a total capacity of 516 l/s.
In this project, the construction of two transmissions lines with 52 storage tanks (14 of which were existing), 11 pumping stations (4 of which were existing) were proposed. In addition, the water supply network was divided into 29 zones to provide a minimum and a maximum operating hydrostatic pressure of 30 m and 80 m, respectively.
This project was prepared about 15 years ago and construction activities were partially completed. During this period, the project was also partly modified. For instance, the pipeline coming from Derindere Spring was changed to steel pipe despite the fact that the pipe was designed to be asbestos cement. The Asbestos Cement (AC) pipes were only used in the secondary network. The special health and safety precautions that need to be implemented during the renewal of the aging asbestos cement pipes within the scope of this WB funded project are discussed in detail in Chapter 4: Mitigation Measures.

3.1.3. Sedes Project

Another project “Baglarbasi Municipality Water Supply Network Project” has been prepared by SEDES Engineering Ltd. in 1999. This project intended to supply water to certain parts of the city. However, these areas are not situated in areas where pipe renewal activities will be carried out as a part of this EMP. This data is provided for completeness purposes only. A brief summary of this project is presented as follows:

Projection population = 51,000 inhabitants

Specific per capita domestic water consumption q = 170 l/cap/day

Population density= 100 cap/ha

Gokpinar transmission line: Flow: 47 l/s Pressure (operational): 568.59 m.

Zeytinkoy well: Flow: 13 l/s Elevation: 430 m

Well numbered 20/3063: Flow: 50 l/s Elevation: 478 m.

Lowest elevation of the project area in the existing map= 392 m

Highest elevation of the project area in the existing map = 700 m

3.1.4. Final Feasibility Report of Denizli Water Supply System Rehabilitation Project

In accordance with the agreement signed on 7.3.2005 by Kaya-SNS joint venture, “Denizli Water Supply System Rehabilitation Project Final Feasibility Report” was prepared. In this report, the purpose of the feasibility was determined “to evaluate the water supply and distribution system of Denizli Municipality, to isolate the demands for investments by pointing out the existing problems and bottlenecks in order to establish a system that will serve the needs till 2040, to conduct financial analysis of the investments, to determine the bases for water tariff fixation for providing sustainable operational conditions and to suggest the required institutional arrangements”. Major outcomes of the final feasibility report are summarized as:

• 
  Evaluation of existing municipal water supply system
  
• 
  Determination of required investments and their economic analysis
  
• 
  Determination of demand on external support based on financial capacity of the municipality
  
• 
  Determination of demands for sustainable operational conditions in the system and bases for water tariff fixation
  
• 
  Time planning of the rehabilitation works and assessment of tender methods
  

In this report; Denizli Municipality was set to be the owner and the beneficiary of the project whereas Bank of Provinces, State Planning Agency and Undersecreteriat of Treasury were designated as the shareholders. Additional issues mentioned in the report are as follows:

In this report, the mean monthly domestic water consumption per household in the province of Denizli in 2004 was computed to be 9.3 m³ for a house. In other words, it corresponds to the amount of water consumed by a flat or a house with 3 or 4 inhabitants. This amount is billed as 6.98 YTL (3.93 EURO) and is about 0.92% of average gross income of a family. This rate is about 4% in the world and it is therefore thought that this value could be increased.
Similarly, it was also stated in the report that per capita expenses comprising water supply, wastewater collection and treatment as well as solid waste management (Urban Infrastructure) was 37 YTL (21 EURO). Water budget of 2003 was also presented in the report. However this data is updated with 2008 values and is given in the Fig. 3.1. The shaded boxes in the figure represent water losses. Based on this water budget, “Infrastructural Loss Index” (ILI) that is defined as a simple ratio of the “Technical Indicators of Real Losses” (CARL) to the “Unavoidable Average Real Losses” (UARL) was calculated as 7.9. It must be noted that for properly constructed and operated systems, this ratio is close to “1”.
Population projections for the 2006-2040 periods (35 years) were made by using the methods of Bank of Provinces and United Nations. Both methods estimated a population value of about 961,000 in 2040. Assuming the average household size of 3.5, the gross amount of water consumption was estimated as 187 l/cap/day in 2003 and 180 l/cap/day in 2004. This value could rise up to 215 l/cap/day during the months in which consumption is maximum. The domestic water demand was evaluated based on these figures. Gokpinar Reservoir that is constructed and Akbas Reservoir that is under planning by the State Hydraulic Works were proposed as potential sources to meet this demand.

Figure 3.1 Water budget as of year 2008

Within the scope of the investment demand evaluation process, a water supply rehabilitation system was introduced in the report and the following measures were proposed:

• 
  Protection of Gokpinar Spring
  
• 
  Rehabilitation of transmission lines
  
• 
  Rehabilitation of pumping stations and storage tanks
  
• 
  Construction of a 1500 m³ storage tank
  
• 
  Rehabilitation of water supply network
  
• 
  Installation of flow and pressure measurement devices
  
• 
  Installation of SCADA system
  

Among the tasks mentioned above, the rehabilitation of the transmission lines, pumping stations and the storage tanks will be carried out by the municipality. To this end, only the renewal and replacement of the secondary water supply network is within the scope of this WB-funded project that this EMP is based on. The project area for the renewal of the secondary water supply network is presented in Fig. 3.2.

3.1.5. Prevailing Conditions

As mentioned in the project descriptions given above, there are three sources that water is abstracted from to supply the needs of Denizli:

1. 
   Gokpinar Spring
   
2. 
   Derindere Spring
   
3. 
   Deep wells
   

Annual total amount of water abstracted from Derindere and Gokpinar Springs are given in Fig. 3.3 and Fig. 3.4. As seen from these figures, about 600 l/s and 125 l/s water is abstracted from Gokpinar and Derindere Springs, respectively. In addition, the total amount abstracted from the deep wells is about 445 l/s according to records dated 28.6 2007. As mentioned in the feasibility report Asbestos Cement (AC) pipes in the initial parts of the Derindere transmission line were changed to steel pipes 3 years ago in order to prevent a loss of about 20 l/s water. The old AC pipes were sent to the Izaydaş Hazardous landfill site. The municipality conducts certain works for the preservation of these resources. One of these preservation measures is fence installation particularly along the roadside of the reservoir in order to prevent accidents that might affect the Gokpinar Spring reservoir. Another opinion is rerouting the road. These are still debated and some precautions are expected to be taken in the short term.

Currently, water collected from these resources is disinfected via the chlorination unit located at the Gokpinar storage tank. This system is under operation for the last 10 years. Chlorine gas is used as the disinfectant. All health and safety precautions related to chlorine gas are taken by the Municipality inside the unit. Among these precautions, ventilation of the chlorine tank storage room via bottom aspirators, emergency pool filled with sodium sulfide, emergency showers for hands, eyes and face as well as an alarm system equipped with light and noise alarms, are the important ones. The chlorine tank storage room is kept locked at all times and only authorized personnel with safety clearance could enter this room.
As to the implementation of the SCADA system, no solid progress has been made. However, “Report on Design Parameters and Criteria for Hydraulic Calculations” was prepared by UBM-SNS group in June 2007 for Denizli Municipality Water and Sewage Authority as a part of the consultancy services for water network rehabilitation, SCADA system design, tender documents preparation and construction supervision (DEN C2). The report ends with some brief information on environmental assessment, cost analysis and the administrative structure of the municipality.
The information given above is not within the scope of this EMP and is provided here for completeness of the report. Currently, Denizli Municipality is focused on minimizing water losses. The project within this EMP work is a part of these activities.

Figure 3.2 General lay out of the water supply system that will be renewed by WB credit.

Figure 3.3 Total amount of water abstracted from Derindere Spring

Figure 3.4 Total amount of water abstracted from Gokpinar Spring

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