Surface -Groundwater Interaction in the Area between El-Timsah Lake and Ismailia Canal Using Hydrochemical and Isotopic Techniques

Abstract

The study aims to understand how surface-groundwater interacts and impact in both water quality in the area between El-Timsah Lake and Ismailia Canal. In order to achieve this aim, and integration of hydrochemistry, trace elements, and environmental stable isotopes investigations were done. Twenty-one surfaces and groundwater samples were collected from the study area. Salinity (TDS) of El-Timah lake differs from 16730- 34560 mg/l indicates the discharge of Ismailia Canal and drainage water into the lake in the eastern and middle parts of the lake. While salinity of groundwater ranged from 345.7 to 1099 mg/l. According to the drinking water quality index (DWQI), most of the groundwater is suitable for drinking purposes but some wells in the study area threatened due to increasing salinity. Stable isotopes δ18O and δ2H of groundwater samples ranged from (2.54-3.39‰) and (22.95-27.79 ‰) respectively. The isotopic content (δ18O and δD) of groundwater is similar to the isotopic content value of the Nile water and Ismailia canal. This confirms that the Ismailia canal and drainage water as a recharge source for the unconfined aquifer. The highest values of nitrate and phosphate concentration in groundwater were observed 53.4 and 1.8 mg/l respectively which are slightly above permissible limits. Also trace elements (Al, B, Fe, Si, and Sr) of some surface and groundwater samples exceeded the international standard limits. Increase nitrate, phosphate and trace elements concentration may be fed rapid pollution path to the underlying, shallow aquifers which may have an impact on groundwater quality.