Abstract
Water is the most precious and valuable natural resource in the Middle East in general and in Gaza Strip in particular. It is vital for socio-economic growth and sustainability of the environment.Gaza Strip is in critical situation that requires immediate efforts to improve the water situation in terms of quality and quantity. Extensive pumping has caused serious quantitative and qualitative problems. Increasing demand due to population increase for fresh water in the last decades cause contamination of the water resources, especially groundwater.If uncontrolled pumping is allowed to continue the aquifer, which is the primary source for the Gaza Strip, will become unusable as a source of fresh municipal water and most agricultural extraction will be too saline for crop irrigation.This paper presents an overview of the Gaza aquifer net balance. The water deficit in terms of quantity will reach to about 70 MCM per year, while the water quality will be deteriorated dramatically.
Introduction
Water is the most precious and valuable natural resource in the Middle East in general and in Gaza Strip in particular. It is vital for socio-economic growth and sustainability of the environment. Groundwater constitutes an important component of many water resource systems, supplying water for domestic use, for industry, and for agriculture.
The use of groundwater has been rising steadily in the last several decades. It has been exploited to sustain a growing population and economical development. The continuous withdrawals and increasing the contaminants make the water scarcity crisis in the relevant environments increasingly influences the economic development, especially in the Gaza strip area where the semi-arid climate dominates.The Gaza Strip, a very small area of land with 367 km2, is situated in the southern part of the coastal plain. The coastal aquifer of the Gaza Strip is part of a regional groundwater system that stretches from the coastal areas of the Sinai (Egypt) in the south to Haifa (Israel) in the north as shown in figure (1). It is generally 10-15 km wide, and its thickness ranges from 0 m in the east to about 200 m at the coastline[1].Under natural conditions, groundwater flow in the Gaza Strip is towards the Mediterranean Sea, where fresh groundwater discharges to the sea. However, natural flow patterns have been significantly disturbed by pumping and artificial sources of recharge over the past 40 years and significant cones of depression have formed over large areas. While Israelis benefit from advanced and reliable infrastructure for the supply of water for domestic use, enabling them unlimited water consumption for all domestic and urban uses. By contrast, Palestinians in the Occupied Territories suffer from an underdeveloped and unreliable water-supply system for domestic use.
Israel's strict control of the water sector in the Occupied Territories, unequal division of the shared groundwater and exploitation of new water sources has prevented development to meet the increasing demand for water, causing a water shortage and crisis. Despite international water resources shared by Israelis and Palestinians, the right of Palestinians to share these resources was not recognized in practice, and the division gradually became discriminatory and unfair.Since the second Intifada in 2000, Israel’s restrictions on movement and access of goods both within West Bank and Gaza and through Israel to the rest of the world have had dramatic impacts on the Palestinian livelihoods. The effects of these restrictions are far-reaching, as they impair planned development, private sector initiatives and livelihoods across all sectors.Present water supplies in Gaza Strip are neither adequate to provide acceptable standards of living for the Palestinian people, nor sufficient to facilitate economic development where the average Palestinian individual daily supply is limited 80 L/ c /d [2]. The limited water resources in the Palestinian governorates face the challenge not only to supply the various water sectors with their water demand, but also has to secure water to meet the increasing needs for people in the future.The sea water infiltration and lateral saline groundwater has further aggravated the pollution of the resources caused by the sewage, fertilizers, pesticides, solid waste and other pollutants infiltration. Hence, at least 90% of the water extracted from this aquifer is not appropriate for human consumption. Less than 10% of water quantities used for drinking in Gaza can be considered fit for drinking, thus reflecting a disastrous environmental, social and humanitarian situation which enforces Population to deliver water by tankers that no longer meets appropriate quality standards and whose price has increased many fold due to increased transportation costs.
Fig1.
coastal aquifer
Source: Palestinian
Academic Society for the study of International Affairs (PASSIA), 2002
Gaza Coastal Aquifer
Net Balance
The major source of renewable groundwater in the aquifer is rainfall. Rainfall is the main natural water source that replenishes the groundwater aquifer, but it is no longer sufficient to refresh the groundwater system. Rainfall is sporadic across Gaza and generally varies from 400mm/y in the North to about 200mm/y in the south as shown in figure (2).
Figure
2. Rainfall sporadic over Gaza Strip
The effective annual water consumption in the Gaza Strip exceeds the recharge that has led to the depletion of the aquifer and infiltration of the sea water.A water balance of the Gaza coastal aquifer based on estimates of all water inputs and outputs to the regional aquifer system. The two largest components of the water balance are municipal and agricultural well abstraction.
Inflows:Effective recharge + Lateral inflow + Total return flowsOutflows:
Total abstraction
The
total estimated inflow to Gaza aquifer of 96 – 101 MCM per year is composed of [3]:
·
Recharge
from precipitation 40-45 MCM per year.
·
Return
flows from leakages 16 MCM per year.
·
Return
flows from irrigation 20 MCM per year.
·
Lateral
inflow from Egypt and Israel 15 MCM per year.
·
Intrusion
from sea water 5MCM/year
The total estimated abstraction from Gaza aquifer of 171 MCM per year is composed of [2]:
·
Municipal
abstraction 89 MCM per year.
·
Agricultural
abstraction 82 MCM per year.
Problem
Statement
- This aquifer is essentially the only source of fresh water in the Gaza Strip that has been continuously over-pumped to serve the high population resulting in falling water levels and degrading water quality. The Gaza coastal aquifer is a dynamic system, with continuously changing inflows and outflows. The present net aquifer balance in the Gaza Strip is negative; that is, there is a water deficit. Under defined average climatic conditions and recent pumping and return flows, the net 'recent' deficit is about 70 MCM per year. Implications of the net deficit include:
- Lowering of regional water levels.
- Reduction in availability of fresh groundwater.
- Seawater intrusion, and potentially up-coning of deep brines.
The net deficit has led to a lowering of the water table in the past 30-40 years and inland migration of seawater. Of these two factors, seawater intrusion accounts for a greater fraction of the volume loss, but it is less visible and thus tends to lessen the perception of the worsening aquifer evolution.
The rapid rate of population growth in the Gaza Strip and dependence upon ground water as a single water source present a serious challenge for future political stability and economic development.
Conclusion
This over abstraction has led to a deterioration of water quality including high levels of salinization from sea water since the amount pumped from groundwater is much higher than the natural replenishment of the groundwater aquifer.If uncontrolled pumping is allowed to continue the aquifer, which is the primary source for the Gaza Strip, will become unusable as a source of fresh municipal water and most agricultural extraction will be too saline for crop irrigation and threatens the long term sustainability of important water resources which will also impact upon future generations.So Gaza Strip is undergoing a humanitarian crisis which is violations of the human right to water that have been caused or exacerbated by the sanctions and blockade. It is in critical situation that requires immediate efforts to improve the water situation in terms of quality and quantity and a serious water management strategy in the Gaza Strip.There are many scenarios and solutions to provide additional sources of water supply such as rainfall collected individually by families on roofs of their houses, treated wastewater for agriculture, imported water from neighboring countries through water tanker. Local alternatives such as brackish and/or seawater desalination has been focused on.
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