In the immediate aftermath of the Gulf War in 1991, the United Nations sent a mission to Iraq which reported the makings of “an imminent catastrophe ... if minimum life supporting needs are not rapidly met.” The Security Council responded by offering Iraq, in August 1991, an opportunity to sell oil to meet its people’s basic needs while the sanctions, imposed in August 1990, remained in place. That offer was not accepted and over the following five years there was widespread suffering with food shortages, an absence of essential medicines and a general deterioration in essential social services.
In 1996 the Government of Iraq and the United Nations Secretariat reached an agreement on a Memorandum of Understanding, setting out the details of implementing Security Council resolution 986 (1995) which had been adopted 13 months earlier. Resolution 986 (1995) set terms of reference for the "Oil-for-Food" programme.
"Oil-for-Food" is a unique programme, established by the Council as a temporary measure to provide for the humanitarian needs of the Iraqi people.The programme is funded exclusively with proceeds from Iraqi oil exports, authorized by the Security Council. Currently 72 percent of Iraqi oil export proceeds goes to fund the humanitarian programme, of which 59 percent is earmarked for the contracting of supplies and equipment by the Government of Iraq for the 15 Central and Southern Governorates and 13 percent for the three Northern Governorates, where the United Nations implements the programme on behalf of the Government of Iraq.
There are nine United Nations agencies and programmes involved in the "Oil-for-Food” programme. These are: FAO, ITU, UNDP, UNESCO, UN-Habitat, UNICEF, UNOPS, WFP, and WHO.
FAO is implementing the IRAQ/SCR 986 Three-Year Agricultural Programme in the three Northern Governorates, for the sustainable rehabilitation of the agricultural sector, including all aspects of agriculture, forestry and fishery. The Water Resources and Irrigation Sub-Sector (WRISS) is the largest of the agriculture-related activities in the three Northern Governorates, with six major fields of activity as follows:
- rehabilitation of existing irrigation infrastructures, ensuring agricultural production on irrigable land;
- construction of new irrigation schemes, extending the irrigated area, and introducing water saving irrigation technologies;
- water harvesting through the construction of run-off collection dams and soil and water conservation measures, increasing soil moisture availability for crop production;
- drilling of deep wells, rehabilitation of shallow wells and maintenance of springs, increasing groundwater resources use for crop production;
- water resources management, ensuring water availability for irrigation purposes in sufficient quantity and quality;
- human resources development, ensuring local professional capacity building and institutional strengthening.
Within the framework of WRISS, a groundwater unit (GWU) was established with the objective of appraising the groundwater availability of the region and identifying sites for groundwater exploitation.
The general objective of the study was to provide the field team of WRISS/GWU with information to facilitate and speed up their ground investigations for groundwater appraisal and exploitation.
In this framework specific objectives were:
- to provide a reliable and uniform topographic coverage of the three Iraqi Northern Governorates;
- to provide, from remote sensing data, detailed information on drainage and watersheds;
- to prepare a comprehensive database in ArcView format including layers from remote sensing data interpretation as well as from traditional data, relevant for groundwater search and hydrological applications;
- to identify for the 30 areas selected by the field team, encompassing a total of 2 044 km2, specific potential groundwater sites for the necessary ground investigations (field checking and geoelectric surveys) and subsequent drilling, coupled with the information on lithology, geomorphology and, when possible, on expected water quality for every site.
The study area covers entirely the three Iraqi Northern Governorates (Dohuk, Erbil and Sulaymaniyah) encompassing 40 627 km2 (Fig. 1). The main features of the region are reported herein.
Fig.1. Study area
Physiography
Northern Iraq can be divided into three main physiographic zones, namely:
1. The northern range of the Zagros Mountains
2. The central range of the Border Folds
3. The southern plains of the Tigris River
The north-northeastern part is characterized by the Iraqi Zagros Mountain range with heights up to 3 600 m above sea level (a.s.l.). This range separates the three Governorates of Northern Iraq from Turkey to the north and from Iran to the northeast. In this area morphology is rather rough, with steep slopes and narrow valleys. Snow coverage is common at high altitudes and vegetation cover is widespread, constituted of both grasses and forests.
A smoother morphology occurs in the central part; the area being characterized by an anticline/syncline system (the Border Folds, Boccaletti and Dainelli, 1982) which gives rise to a relief with a general orientation NW-SE. Heights up to 2000 m a.s.l. are reached. Wider valleys occur in this zone, which are strongly influenced by tectonic control. Vegetation is rather sparse, mainly herbaceous.
The southwestern part is dominated by the low alluvial plains of the Tigris River and its tributaries. Average altitude is around 400 m a.s.l.
Geology and hydrogeology
Northern and north-eastern Iraq geologically are part of the extensive alpine mountain belt of the Near East. The Taurus-Zagros belt developed during the collision of the Afro-Arabian continent with the Eurasian continent (the latter including a number of microplates and island arcs) that culminated in the Miocene-Pliocene.
The Taurus-Zagros belt includes two main zones: the folded zone (Border Folds, see above) and the thrust zone. The thrust zone forms the suture zone of the collided plates and occurs as a narrow strip in the extreme north, just outside the border between Iraq and Turkey, and in the northeast, along the border between Iraq and Iran. The folded zone is much wider (~200 km) and can be subdivided according to the intensity of folding into two main parts: the imbricated folds zone, which consists of a relatively narrow zone of intensely faulted and thrusted large folds near the thrust zone border, and the simply folded zone, which is much wider and consists of smaller and less disrupted folds. The simple folds are further subdivided into two subzones: the high mountain zone, which consists of a series of relatively large mostly asymmetric anticlines separated by narrow synclines, and the foothill zone, which consists of a series of relatively small and narrow anticlines separated by wide synclines (Ameen, 1992).
The Taurus-Zagros thrust zone mainly consists of the oldest formations, from Ordovician to Cretaceous, with occurrence of carbonatic and clastic rocks as well as igneous and metamorphics. In the folded zone Triassic to Pliocene units outcrop, mainly sedimentary rocks, with a predominance of limestones and dolomitic limestone. These formations are very significant, because of the intensive karst phenomena and the large volume of potential groundwater storage. Recent Quaternary deposits (alluvium, terrace, colluvium) fill the valleys and follow the main riverbed in the northern and central part, and cover the older Tertiary formations in the plains.
Hydrology
Significant surface water resources occur in the northern part of North Iraq. The major perennial rivers are the Tigris (which runs at or near the southwestern border), the Great Zab, the Small Zab (both in a NNE-SSW orientation) and the Diyala (at the southeastern border of the region). In the northern part of the study area the main tributaries are perennial, however the river runoff reduces towards the south. Ultimately, on the plains, all tributaries (wadis) are ephemeral and dry out regularly by the end of springtime. The main wadis in the south (Erbil area) are Wadi Kurdara and Shiwasor and Wadi Bastora. It is important to note that almost all the major rivers crossing the study area have their origin outside it, namely in Turkey (the Tigris and the Great Zab) or in Iran (the Small Zab and the Diyala), thus their entire watershed covers broad regions outside the study area. Only the Small Zab has a catchment area that extends, for a limited portion, beyond the Northern Iraqi border.
The average discharge of the Great Zab at the Eskikelek gauge station registered over the period 1970-1973 was of 313 m3/s. Daily river flow varied from 118 m3/s to 2439 m3/s. Data from the Altun Kupri station on the Small Zab show an average discharge of 290 m3/s (period 1970-1972), with a minimum of 82 m3/s and maximum of 1 265 m3/s.
Two dams control the Small Zab (Dokan Lake) and the Diyala River (Darbandikhan Dam) in the central part, and their main purpose is to generate hydropower. The construction of the large Bekhma Dam on the Great Zab was not completed. Water from the Dohuk Reservoir and from the numerous impoundments constructed on the smaller rivers is used for traditional irrigation schemes (gravity channels) or for water supply.
Climate
The whole of the study area is characterized by cold and snowy winters and warm dry summers. On the plains, typical semi-arid climatic conditions prevail. Precipitation occurs from October to May, decreasing from the NE to SW. The existing data at Sulaymaniyah meteorological station (in the middle of the territory) show an annual average precipitation of 674 mm for the period 1941-1999. The total annual rainfall registered at this station in 1999 was 338 mm. The mean annual rainfall in the Erbil plain for the period 1941-1970 was 425 mm/year while observed yearly values range between 200 to 700 mm. Rainfall reduction has been observed recently: during the winter and springtime of 1998/99: the observed rainfall was three times lower than average. Comparison of data from all three Governorates for October 1999 to April 2000 shows a reduction of about 50 percent as compared to the mean rainfall for this period of the year.
The following data and softwares were used in the framework of this study:
Satellite data
Landsat Enhanced Thematic Mapper (ETM) data in digital format were preferred over other satellite data due to the availability of three near- to mid-infrared bands, extremely useful for terrain and lineaments analyses. Furthermore, as Landsat ETM provides eight co-registered spectral channels (one panchromatic with 15 m spatial resolution, six bands ranging from visible to mid-infrared with 30 m spatial resolution, and one thermal band with 60 m spatial resolution), this permitted a large spectrum of band combinations, useful in visual interpretation of different features.
In view of the hydrogeological objectives of the study, Landsat ETM data were selected as acquired in the dry season, to evidentiate features (vegetation, soil moisture) related to the occurrence of water and to avoid overshadowing by too much vegetation.
Six Landsat scenes fully covered the study area, but another four were also available, acquired in different months and/or years.
The Landsat data used in the study are listed in Table 1.
Table 1: Satellite data (Landsat 7) used in the study
|
Path |
Row |
Date of acquisition |
|
168 |
35 |
28/06/2000 |
|
168 |
36 |
28/06/2000 |
|
169 |
34 |
03/06/2000 |
|
169 |
35 |
19/06/2000 |
|
170 |
34 |
26/06/2000 |
|
170 |
35 |
09/05/2000 |
Topographic and thematic data
The Operational Navigation Chart (ONC), at scale 1:1 000 000, sheet G 4, edition 10, revised in 1974, available in paper format, was used for a general overview of the area.
Initially the main problem was to locate topographic maps covering the whole area of the study, so as to have a uniform topographic coverage. The field team unfortunately had only topographic maps, at different scales and projections, covering scattered areas. Thus Russian topographic maps, at scale 1:100 000, series J-38 and I-38, in Gauss Kruger projection, were purchased. Maps were provided in raster tiff format by scanning the original sheets.
Lithostratigraphic map, at scale 1:500 000, prepared by Salahaddin University (Erbil) and geological maps, scale 1:100 000 prepared by Gara Bureau (Erbil), Salahaddin University (Erbil) and Sulaimaniyah University (Sulaimaniyah), were provided by the Mapping Unit of the field staff, in paper and raster format. These maps, unfortunately, do not cover the whole study area.
Vector data
Boundaries of the country and of the three Northern Governorates were obtained in ArcView shapefile format from the official FAO GIS database. This data was provided in geographic coordinates (latitude, longitude) and WGS84 datum.
GIS layers in Map Info vector format were provided by the field staff, concerning:
- geology and tectonics for the whole study area at 1:500 000 scale and for seven smaller areas not covering the whole three Governorates at 1:100 000 scale;
- springs and deep wells drilled by FAO all over the study area.
Table data
MS Excel worksheets containing data on springs, deep and shallow wells for only five areas in the three Governorates (Aqra, Arbat & Kourmal, Chamchamal, Sumail and Zakho) were provided by the field team.
Softwares
The following softwares were used:
ENVI 3.5 (and later on 3.6) was used for georeferentiation and general image processing. The same software was used by the field team;
ERDAS 8.4 for visual analysis and interpretation;
ArcView 3.2 for GIS data acquisition, analysis and presentation. A freeware extension, named "Rose Tool" was used for creating rosette diagrams from lineaments data;
Terranova ShArc 3.0 for vector data editing.
