Compilation and mapping of hydrogeological data for the Tadla irrigation perimeter

¹ Geo-Resource Geo-Environment Geological and Oasis Heritage Research Team, Department of Geosciences, Faculty of Sciences and Techniques, Moulay Ismail University, Errachidia, Morocco.
² Georesources and Environment Laboratory, Department of Earth Science, Faculty of Science and Technology, Moulay ISlimane University, BP 523, Mghila, 23000 Beni Mellal, Morocco.
³ Laboratory of Geoengineering and Environment, Research Group “Water Sciences and Environment Engineering”, Department of Geology, Faculty of Sciences, Moulay Ismail University, Zitoune, BP11201 Meknes, Morocco.

^* Corresponding author: c.iharzi@edu.umi.ac.ma

Abstract

With its lush fields and neighboring mountains, the Tadla Plain in central Morocco is an important agricultural area. Its climate is semi-arid to arid, with a dry season from June to September and a rainy season from October to May. Summer temperatures exceed 30°C, while winter temperatures fall below 5°C. The area, which is a part of the Oum Erbia River basin, is mostly dependent on groundwater for industry, agriculture, and drinking. In this study, 58 wells (42 from ORMVAT and 16 from ABHOER) were analyzed to determine the water table levels and groundwater quality. Different physico-chemical and bacteriological parameters were analyzed, such as, pH, EC, Cl⁻, NO₃⁻,SO₄²⁻, etc. As well as hydrodynamic data including permeability, transmissivity, storage coefficients, and piezometric levels. With permeability between 10⁻⁵ and 10⁻³ m/s and transmissivity between 1×10⁻³ and 5×10⁻² m²/s, groundwater flows from northeast to southwest, indicating moderate to strong water transmission. Moderate storage capacity is indicated by storage coefficients ranging from 3×10⁻² to 6×10⁻². However, the quality of groundwater varies; many wells, particularly in the Beni Amir nappe, exhibit poor quality. Concentrations of electrical conductivity (EC) and chloride ions (Cl-) are high in most wells.