Water Resources

The Tulkarm district is underlined hydrologically by the northern part of the western groundwater basin within the Auja-Tamaseeh drainage basin. This basin is shared between Palestinians and Israelis, where 7% of its capacity is being utilized by Palestinians while the rest is being utilized by Israelis. It is located geographically in the semi-coastal region.

Hydrological Status

The Tulkarm aquifer constitutes the northwestern part of the West Bank aquifer to the west of regional watershed, which subdivides the Mountain Aquifer into east and west basins. Participation of this area in the water budget is significant since its long term average annual rainfall exceeds 500 mm. Groundwater flow is directed towards the west and northwest.

Groundwater Aquifer Systems

The main aquifer systems in the area are:

1. Upper Cenomanian-Turonian Aquifer system, where the majority of Palestinian wells are tapped. It is composed of limestone, dolomite and marl with joints and karsts that give its aquifer properties. It has different aquifer formations including Hebron, Jerusalem and Bethlehem, which are exposed in the study area (Rofe & Raffety, 1965).

2. Lower Cenomanian Aquifer, which underlies the upper Cenomanian Aquifer. A small number of Palestinian wells are tapping this aquifer. This system is represented by Lower Beit Kahil and Upper Beit Kahil geological formations, which form good aquifers (Rofe & Raffety, 1965).

3. Eocene Aquifer of the Tertiary chert, which consists of limestone and sandstone. Few outcrops are found in the eastern part of the study area (Rofe & Raffety, 1965).

Sources of Water

Surface Water

Surface water resources are represented by limited amounts of winter flood water. As shown in Figure 2.4, there are several drainage systems in the Tulkarm district, and the main wadis have a total annual runoff of about 8 MCM (PLO, 1990). As stated in the PLO report (1990), the main drainage systems in the Tulkarm district are:

1. Wadi Abu Nar in the northern part of the Tulkarm district with an annual discharge of 2.77 MCM.

2. Wadi Massin with an average annual discharge of 1.35 MCM.

3. Wadi Zeimar with an average annual discharge of 3.18 MCM.

4. Wadi et Tin with an average annual discharge of 0.73 MCM.

Very limited uncalculated water quantities are being utilized from these floods through cisterns and small catchment areas to harvest water in the form of agricultural ponds. Many Palestinians are using the roofs of their houses as well as plastic houses to collect water and store it in small reservoirs or cisterns.

Groundwater

As there are no springs in the area, groundwater in the Tulkarm district is being utilized through wells constructed to tap the groundwater aquifers. Groundwater wells are used to provide Palestinians with water for both domestic and irrigation purposes. Figure 5.1 shows the location map of groundwater wells in the Tulkarm district.

Figure 5.1: Location Map of Groundwater Wells in the Tulkarm District

Domestic wells

There are 16 groundwater wells used for domestic purposes in the area, 10 wells in Tulkarm sub-district and six in Qalqiliya sub-district. The basic data on the municipal wells of the two main cities (Tulkarm and Qalqiliya) are shown in table 5.1 below.

Irrigation wells

There are 131 wells used for irrigation purposes in the Tulkarm district, 72 wells in the Qalqiliya sub-district and 59 in the Tulkarm sub-district.

Groundwater Quality

ARIJ has conducted a water sampling procedure for chemical and physical analysis to identify water quality. For that purpose 80 water samples representing 80 wells in the Tulkarm district were taken and analyzed at the laboratories of the College of Science and Technology, Al-Quds University. The sampling procedure was conducted to fulfill the requirements of the current project on irrigation management supported by the Canadian International Development Research Center (IDRC).

Physical Water Quality Parameters

The physical water quality parameters were measured on site using portable meters during the sampling procedure conducted in March-April, 1995. These parameters include pH, electrical conductivity (EC) and temperature.

The data shows that in the Tulkarm area, EC ranges from 242 to 1623 µS/cm with an average of 646 S/cm, while in Qalqiliya it ranges from 152 to 1432 µS/cm with an average of 598.5 µS/cm. Temperatures range from 4.4 to 23.6 ⁰C with an average of 17.8 ⁰C for Tulkarm and 5.5 to 23.2 ⁰C with an average of 20.9 ⁰C for Qalqiliya. The pH ranges from 6.6 to 8 with an average of 7.07 and from 6.7 to 7.7 with an average of 7 for Tulkarm and Qalqiliya respectively.

Chemical Water Quality Parameters

The chemical analysis was conducted to identify the following constraints:

- Cations: Calcium (Ca⁺²), Magnesium(Mg⁺²), Sodium(Na⁺) and Potassium(K⁺).

- Anions: Bicarbonate (HCO₃^-), Chloride(Cl^-), and Nitrate(NO₃^-).

Calculated Water Quality Parameters

Physical and chemical results of water samples were used to calculate sodium adsorption ratio (SAR), Hardness (Hr) and Sodium percentage (%Na).

Presentation of Hydrochemical Data

The above mentioned hydrochemical data were presented using the following tools:

1. Wilcox Diagram

This diagram represents the relationship between physical and chemical results represented by electrical conductivity (EC) and sodium adsorption ratio (SAR), respectively. EC represents the salinity indicator and SAR represents the sodium hazard indicator. Figure 5.2 shows the presentation of hydrochemical data on Wilcox diagram (Wilcox, 1955). Wilcox diagram shows that water is located in the region of medium to high salinity and low sodium hazard (C₂-S₁) and (C₃-S₁).

Figure 5.2: Presentation of Hydrochemical Data on Wilcox Diagram for the Tulkarm District

2. Water Quality Distribution Contour Map

Contour maps were presented for EC, Cl^-, NO₃^- and SAR to show the geographic distribution of water quality in the area. Figures 5.3, 5.4, 5.5 and 5.6 show contour maps, where the changes in these parameters can be related to industrial pollutants, agricultural practices and others.

Figure 5.3: Electrical Conductivity (EC) Contour Map of Groundwater in the Tulkarm District

Figure 5.4: Chloride Concentration Contour Map of Groundwater in the Tulkarm District

Figure 5.5: Nitrate Concentration Contour Map of Groundwater in the Tulkarm District

Figure 5.6: Total Dissolved Solids Contour Map of Groundwater in the Tulkarm District

Water Suitability

Domestic Purposes

The average concentrations of the majority of water samples taken from domestic wells are within the limits of different international standards for drinking water. Therefore, the existing Tulkarm groundwater is considered suitable for domestic use. However, overpumping and seepage of pollutants from agricultural areas (fertilizers and pesticides) and wastewater are threatening groundwater quality.

Irrigation purposes

Wilcox diagram was used to classify water for irrigation, where the representative water samples show medium to high salinity hazard and low sodium hazard.

Water Supply and Demand

As mentioned before, groundwater is the only source of water supply in the Tulkarm district. Water supply in 1994 was measured to be 16.62 MCM for agricultural purposes and 5.6 MCM for domestic purposes so that the total consumption in the Tulkarm district is estimated at 22.2 MCM (WBWD,1995).

The main cities of the Tulkarm district are Tulkarm and Qalqiliya Cities. ARIJ has contacted the municipalities of Tulkarm and Qalqiliya in order to obtain monthly and annual water supply for the year 1995. Table 5.2 shows the municipal wells of Tand Qalqiliya and their pumpage per month on a monthly basis. Tulkarm Municipality has three wells while Qalqiliya Municipality has two wells.

As shown in Table 5.2, Tulkarm municipal wells provided 2,097,200 m³ while Qalqiliya municipal wells provided 1,268,634 m³ in 1995. In order to compensate for the deficit in the current needs of water for the population served by Tulkarm Municipality, 678,910 m³ were purchased from private agricultural wells. So, the total quantity of water supplied for the local inhabitants within the boundaries of Tulkarm municipality was 2,766,110 m³ in 1995. Water supply in the Tulkarm district does not reflect the actual water consumption because of leakage in the water distribution networks, which reach 25-50%. Isaac et al. (1995) conducted an updated study of water supply and demand to estimate the amount of water required in the Tulkarm district. The following scenario was published for the study area (Medium Scenario)

Per capita annual domestic consumption in the Tulkarm district is estimated at 41 m³, while in Israel, the annual domestic consumption is about 100 m³ and has been growing at an average rate of 0.6% per year over the last decade (World Bank, 1990).

Water Distribution Network

Data on water distribution networks for the main cities of Tulkarm and Qalqiliya were collected, while other villages in the district do not have water distribution networks' drawings. The water distribution network of Tulkarm City was installed in 1933. The leakage in the network is very high and may reach 50% of the water pumped. It currently covers 70% of Tulkarm City in addition to pipes reaching the villages of Dannaba, Shuwaika, Eirtah and I'zbet Ej Jrrar. Approximately 17 km of the network is being replaced within a two-year plan to replace 50 km. Figure 5.7 shows the current water distribution network in Tulkarm City.

Figure 5.7: Water Network in Tulkarm City

The water network in Qalqiliya City covers 100% of the city with a total length of 70 to 75 km ranging from 18 to 1/2 inches with a leakage of 45%. Figure 5.8 shows the current water distribution network in Qalqiliya City.

Figure 5.8: Water Network in Qalqiliya City

Water Reservoirs

There are seven reservoirs in Tulkarm City and the nearby villages, and two reservoirs in Qalqiliya Municipality with a capacity ranging between 200 to 2,000 m³. Table 5.4 shows the names and capacities of these reservoirs.

Water Prices

Table 5.5 shows the current tariffs of water in Tulkarm and Qalqiliya Municipalities, where the unit price increases with the increase in consumption. In Israel, tariffs are 12.5 to 26 cents/m³ for agriculture, 32 to 75 cents/m³ for domestic use depending on whether the amount of water consumed is less than 16 m³ or more and 15 cents/m³ for industry (World Bank, 1990). In the Hebron and Bethlehem districts, water prices are much higher than the prices in Israel, where it is between 78 to 85 cents/m³ and $ 1.25 per m³ respectively.

minimum charge which the municipalities take if water consumption is less than 5 m³ in Tulkarm and 9 m³ in Qalqiliya.