This study presents the results of investigation activities conducted at the reclaimed lands Project site in Mutoubes District, Kafr El-Sheikh Governorate, Egypt,in order to figure out the main causes of deterioration/damage of the existing tertiary canals (Mesqas)concrete linings. Detailed field investigation was performed, whilst all available technical documents on this project were studied. The testing program consisted of laboratory as well as field tests. Several boreholes were dug along the lined canals' embankmentsto cover the study area.Soil samples were collected from different depths at 30 cm intervals. All samples were tested for theirchemical, physical, and mechanical properties. Irrigation water, drainage water, and groundwater samples were also collected and tested in the laboratory.On the other hand, the old lined mesqaswere visually assessed. According to field observations and results of laboratory tests, the main causes of damage to the new lined mesqaswere identified. The outcomes presented in this papermayemployed to propose an appropriate maintenance solutionfor the damages of the new lined mesqas; and to recommend the most promising protecting alternative for the old lined mesqas.