Introduction

Balochistan province of Pakistan lies in the arid climatic region where rainfall is very low and its spatial and temporal variability is very high. Lift irrigation, spring and karezes are the main sources of water for agriculture and domestic uses. The karez-irrigation system is the peculiar and the oldest gravity irrigation system which was built centuries ago. It provides safe and free (under gravity) water supply for both irrigation and domestic uses, round the clock and throughout the year. The evaporation losses are minimal and its underground coverage protects against sediments from wind storms. It is owned and managed by the community and every community member benefits from it in one way or the other. The other sources such as dugwell sand tube wells are owned by individuals, need heavy capital investment, require energy for its operation and can be operated for specific period of time (e.g. when electricity is available). The karez-irrigation system is used in around 22 countries such as Pakistan, Iran (locally called as Qantas), Afghanistan, Tunisia, China etc.
A karez is a masterwork of hydraulic engineering and cultural unity. It is an underground horizontal tunnel dug below groundwater level to intercept water. These are normally 1-5 km long, though some are as long as 50 km. A karezpicks up water from a mother well, either an underground spring in the piedmont zone or a subsurface flow on the bank of a temporary river and conveys water over a length of 500-3000 m, before it reaches daylights close to the agricultural command area (Fig. 1).The water is then channelized in watercourses to the farmlands for irrigation. The beds of the tunnels are mildly sloped, over which the intercepted water flows at a low velocity. The tunnel is provided with access wells (vertical openings to ground surface) at frequent intervals, normally every15 to 30m, for light and ventilation. These wells are also used for tapping drinking water and removal of excavated material, required during maintenance. A karez discharge varies from 53 to 3700 lps. Similarly, availability of discharge per unit irrigated land substantially varies from karez to karez. Each karez has well established water distribution system.

Objectives

• To assess technical, economic and social aspects for rehabilitation and conservation of Karez water system;
• To build technical capacity through rehabilitation and maintenance of selected non-functional Karez system; and
• To develop networking with concerned institutions in the region to share the information and experience in the traditional water systems.

Introduction

About 60% of the total culture able area of Sindh is under water-logging and salinity (IWASRI, 2015).Extensive groundwater pumping in the sweet zones has further aggravated the situation through saline water up-coning which causes secondary salinization and un-even availability of canal water supplies in the command area, tail-end farmers get less water as compared to head and middle farmers and use groundwater for ripening of their crops. In addition to groundwater depletion in specific pockets, the groundwater quality also deteriorates at tail-ends due to less recharge. The groundwater contribution is helping to meet supplementary irrigation water requirements. Therefore, canal command scale groundwater investigation and mapping is imperative for the demarcation of fresh water zones as well as sustainable water management to meet the crop water requirements.

The groundwater hydrology is a very specialized field and involves geo-physical, isotopic, hydro-geochemical and groundwater modeling applications. The Pakistan Council of Research in water resources (PCRWR) is a federal apex research organization having regional offices throughout the Country. PCRWR has established state of the art laboratories including groundwater investigation cells and also has the credit of having only ISO certified water quality laboratory network in Pakistan.

Objectives of the Study

• Analyzing spatial variations in depth to water table on seasonal basis (Pre-Moonson and Post-Moonson)
• Demarcation of spatial variation in groundwater quality and identification of usable groundwater pockets
• Assessment of canal water discharges and calculation of seepage rate

Scope of the Study

• The scope of this study covers the irrigated areas falling under the canal commands of 14 major canals in Sindh province including Thar Desert as well as Malir Area (cultivated area between Hyderabad – Karachi).
• Keeping in view of financial limitations and time constraint, PCRWR will mainly focus 14 main canal command areas under this study whereas; the remaining areas will be complemented voluntarily through its other projects.
• However, the final report will be very comprehensive enough to encompass all the areas of interest as mentioned above with solid recommendations.
• Additionally, PCRWR has decided to conduct bathymetric studies by applying Acoustic Doppler Current Profiler (ADCP) and seepage meter to characterize the hydraulic parameters such as canal discharges and seepage rate calculations voluntarily in national interest.

Expected Outcome                                                          

After completion of the project, it is expected to have a GIS mapping of groundwater resource of Sindh Province. This study will provide an insight about the current status of groundwater and will facilitate the water resource managers for strategizing the efficient utilization of groundwater in conjunction with surface water. Furthermore, it will help to provide equitable distribution of water supplies from head to tail ends in the 14 main canal command areas.

Objectives 

• To investigate sea water intrusion along the coastal zone of Pakistan through scientific observations to assess rate of sea level rise and land subsidence.
• To find out causes of erosion through scientific observations and relevant data for assessing its impacts on coastal areas.
• To develop mitigation strategy for countering sea water intrusion and coastal erosion.

Expected Outcome

The project will provide hydrographic/oceanographic observations, remote sensing data and identification of hotspots to determine/forecast rate of coastal changes with time.