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Aquifer zones had been explored by the geo-electrical method of electrical resistivity survey (ERS) to mark out subsurface formations in terms of groundwater quality and quantity. The main focus was on identification of subsurface litho-logy and aquifer zones by resistivity method in parts of the Havelian Cantt, Abbottabad district, Khyber Pakhtunkhwa (KPK) Province and Sanjwal Cantt, Attock district, Punjab Province, Pakistan. Evaluation of the lithology of subsurface strata was carried out by electrical resistivity survey (ERS) interpreted by software packages 1X1D using ABEM Terrameter SAS-4000. The different 05 sites were selected for ERS after identifying feasible locations. Data acquired was processed using the Schlumberger electrode configuration (SEC) to determine the characteristics of target layer. The results showed that groundwater level (GWL) at Havelian Cantt sites was at 69 ft average depth with resistivity values between 35-56 ohm-m and formation consist of dominance of gravel/boulder mixed with sand/ sand stone and thin layers of clay. GWL at Sanjwal Cantt sites was at 50 ft average depth having low to moderate yield of water and the formation had dominance of sand with alternate layers of clay against resistivity between 25-86 ohm-m. The study concluded that electrical resistivity survey (ERS) is a sound method for measuring GWL in sandy aquifers and boulder clayey formations when GWL is sufficiently deep.

This paper highlights the problems associated with the outlets in the irrigation system of Pakistan, leading to the design of outlets, to trace the gradual evolution of various outlets types and to describe most of the types that have been evolved so far. The advantages and limitations of each type have been examined critically so that the selection of a type for any particular set of conditions may be rendered easy. An outlet is a flow measuring and controlling device between farmer’s land and an irrigation system. In Punjab about fifty thousand outlets irrigate an area of approximately 25.5 million acres annually. Improperly designed outlets may cause a number of problems such as variation in their coefficients of discharge, inequitable distribution of water, silting of canals, inadequate availability water at the lowest outlets, lack of incentives for saving of water and poor drainage. Field calibration of the irrigation outlets proved that their calibrated Cd. vary from the designed Cd. (0.6 for OF & 0.9 for AOSM), as outlets were not designed according to their designed parameters. Defective outlets were also the main cause of silting in canals. The pipe-cum-semi module was very helpful to draw silt from the bed of the parent channel in a case if we want a higher setting of outlet. 20% of canal water in Rabi season and 40% water in Kharif season were snatched by illegally Theft problem. In order to prevent theft, the outlets should be tamper proof and the irrigation department should adopt the legal procedure strictly. All over the world, the engineers and farmers designed and installed various kinds of farm outlets suiting their local conditions. Work is being carried out to make them structurally, hydraulically and economically fit. An attempt is made to bring all the information together leading to economical and efficient design of outlets and to look upon their possibility of adaptability in Pakistan.

Surface and subsurface drip irrigation methods can play a significant role in overcoming the scarcity of water mostly in water shortage areas. A field study was conducted to know the effectiveness of surface and subsurface drip irrigation systems under different plasticity pipes, in terms of both water use requirement and yield of date palms at Al-Qassim, Saudi Arabia. Mature palm trees of different varieties with 10 m spacing for both row to row and tree to tree were selected. Three types of pipes (low, medium and high flexible that is, with wall thickness of 1.14, 0.38 and 0.41 mm, respectively) were used in both surface and subsurface drip irrigation systems. Irrigation scheduling was done through a soil moisture sensing device as well as crop water requirement guidelines for Kingdom of Saudi Arabia to ensure enough soil water levels in the soil. Considerable effects of pipe stiffness were observed on water consumption and yield for both surface and subsurface drip irrigation systems. It was found that irrigation water reduced to 36 and 56% for drip pipes of low flexibility under surface drip irrigation system while it was 49 and 53% under subsurface drip irrigation system due to better physical and hydraulic characteristic of pipe as compared to that for medium and high flexibility pipes, respectively. The yield of date palms was increased by 45 and 48% more in case of low flexibility pipe compared to that for other two types under both drip irrigation systems. Date palm response by using low flexible pipe under both surface and subsurface drip irrigation was found relatively good in respect of water consumption, yield and irrigation system itself.

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