Lake Timsah - Environment

Environment

Lake Timsah is a brackish lake that experiences significant variations in salinity. Human engineering projects have impacted salinity, with resulting changes in the lake's biota. Decreases in salinity were noted as early as 1871 following Suez Canal construction, and subsequent enlargement of the channel from the Nile and other construction projects increased the inflow of fresh water to the lake. The El-Gamil outlet serves as Lake Timsah's principal source of salt water. Timsah's main source of fresh water was annual Nile flooding until the Aswan High Dam interrupted these flows in 1966, although groundwater also accounts for much of the lake's freshwater supply. Lake Timsah experiences both stratification variations in salinity and seasonal surface variations in salinity, and in recent decades freshwater taxa have been overtaking brackish taxa.

In 2002, a study was conducted to check the concentrations of polycyclic aromatic hydrocarbons (PAHs) in fish and shellfish species that locals consume from the lake. Samples included tilapia, crabs, bivalves, clams and gastropods. The results showed that crabs contained "significantly higher concentrations of both total and carcinogenic PAHs than other species, while clams contained significantly lower levels of PAHs."

In 2003, a number of groups attempted to relieve the lake of pollution. It was a significant event for the local community, since the lake is of economic importance to the city and its fishermen.