The study aims to assess the efficiency and susceptibility of aquifers and geological formations in Salahaddin to store excess surface water in rainy and flood seasons, to be alternatives for surface aquifers and to achieve an increase in groundwater levels. Five sites that represent several hydrological basins have been selected for artificial recharge experiments, in which two types of experiments were conducted. In the first, the water was injected into the recharge well with monitoring the level in the same recharge well. In the second, water was injected into the recharge well and the water level was monitored in a close well to the recharge one. Test infusion experiments have been conducted in some locations, and data of water level drawdown was drawn in against time in the form of hydrographs, by using Excel program with attempting to analyze groundwater behavior and movement within the unsaturated layers of the aquifer. Then, the hydraulic properties have also been calculated in some locations from pumping tests or artificial recharge experiments and drawing the hydrograph curve using (Aquifer win32). The study concluded that all the aquifers, in which the artificial recharge experiments were carried out, were very efficient in their response to injections, with minor variations due to heterogeneity of porous media and the thickness of unsaturated zones, which cause different permeability between layers, and different hydraulic properties of aquifers.

No abstract

The area was hydrogeologically studied, it was found that the main aquifer is unconfined, it is located within Fat’ha Formation, and the hydraulic properties of this aquifer were also studied from the analysis of pumping tests data to determine the averages of transimissivity (T=671.027 m2/day), hydraulic conductivity (K=45.449 m/day), and storage coefficient (Sc=0.226). The groundwater levels and flow direction map was drawn, and it was found that the flow corresponds to the topographical slope of the land surface towards Tharthar valley, from the east - west towards the center of the study area, with a slight slope towards the south. These are some data represent a database that can be used in the design of the proposed dam on Tharthar valley, and the policy of storage and water management in the dam, reservoir as well as to build a mathematical model to predict the future behavior of groundwater in the region. Especially under the body of the dam to simulate the changes in groundwater conditions in the area of the small Hatra Dam Suggested on Tharthar valley, when storing water in front of a dam, and the expected engineering problems that would occur due to groundwater seepage under or on both sides of the dam body, by raising the water level within the valley – hypothetically, by 1m, 2m, 3m, 4m, 5m, 7m, 9 m and 11 m, assuming no pumping from the Aquifer during the rise of the level in the valley. as well as re-calculation with the same ranges of raising the level on another assumption, which is pumping from the wells in the area by 9 m3/ hour, for a period of time 6 hours per day, and determining the affected area by raising the level for each of the cases. The study indicated that the expected effect on the groundwater level starts when raising the water level inside the valley to four meters, and the clear increase continues at five meters, but the cumulative effect of raising the level from (7-11)m is slight. It also identified the sites that would allow the underground water to be pumped under the dam’s body, and the results were consistent with the geological reality of the area. These results will help in establishing an appropriate design for the foundations and structure of the dam. The current study is one of the requirements for building a small dam within the plan for managing water resources and developing the region that suffers from desertification, drought and environmental degradation.

This study included an assessment of the hydrogeological conditions of the Mishraq sulphur fields before production, by measuring groundwater levels in (11) wells in Mishraq-2 in 2021, as well as the information of wells obtained, which are (12) wells in Mishraq-3, (68) wells in Mishraq-1. Groundwater levels ranged between (187.71-205.80) m in Mishraq-1, while in Mishraq-2 it ranged between (189.19-196.26) m, as for Mishraq-3 the levels were between (186.4-194.98) m. The contour maps were drawn for the movement and levels of groundwater, showing that the direction of groundwater movement in Mishraq field-1 is from the west and northwest to the east, with a slight slope towards the southeast, towards the Tigris River, while in the Mishraq field-2, we notice that the direction of groundwater movement is From the east to the west, that is, toward the Tigris River, as for Mishraq field-3, it was found that the direction of movement is from the southeast toward the northwest, that is, toward the Tigris and Great Zab rivers. So it can be said that the Tigris and Great Zab rivers are the two drainage areas in these three fields. The hydraulic properties were analyzed in (44) wells in the three Al-Mishraq fields. Where the values ​​of Transmissivity (T) in Mishraq field-1 ranged between (24.4-1557.5) m2/day, as for Mishraq-2 it ranged between (23-96.91) m2/day, while in Mishraq-3 it ranged between (10.5-4002) ) m2//day, and the hydraulic conductivity (K) ranged between (0.26 -14.68) m/day in Mishraq field-1, as for Mishraq-2 it ranged between (0.7-4.2) m/day, while in Mishraq-3 It ranged between (0.37-119.09) m/day.