The present study is based, on the one hand, on the water level fluctuations observation and analysis in the Quaternary aquifer of Nouakchott (Mauritania) and, on the other hand, on a comparison of these variations with those of oceanic tide and rainfall. The piezometric network data shows that the flow is from the west to the southeast of the city with the presence of a dome in the center of city (PZ3AXE5) where the piezometric level is 0.8 m.
Recordings were made on a piezometer located 630 m from the coast. Data were collected between July 2017 and July 2018 due to one measurement every two hours. The results showed a tide influence on the water level in the piezometers. We observe that variations in groundwater level simultaneously follow the fluctuations of the ocean. Records show an increase of 0.40m water level for a tide of 1.88 m. The influence of the tides contributes to water table rise under the city of Nouakchott, already saturated by the losses of water pipes, the domestic discharges and the rains.