Environmental Damage Caused by Wastewater Discharge into the Lake Manzala in Egypt

Abstract

Lake Manzala is a brackish lake in northeastern Egypt on the Nile Delta. It is the largest of the northern Delta lakes of Egypt. The Lake is exposed to high inputs of pollutants from industrial, domestic, and agricultural sources. Climate gases and large amounts of particulate matter, nutrients, bacteria, heavy metals, and toxic organics are transported to the Lake through the wastewater discharge. Water samples were collected and subjected to physicochemical analysis and microbiological study. Results have shown great changes in physical and chemical properties of water including: temperature (13.5°C in winter-32°C in summer), pH (7.8-9.2), dissolved oxygen (2.5-12.8 mgl-1), total dissolved solids (1033-43406 mgl-1), total suspended solids (120-387 mgl-1), ammonia (2.5-32.3 mgl-1), nitrite (0-0.076 mgl-1), nitrate (0.01-7.88 mgl-1), phosphate (0.26-2.37 mgl-1), Fe (0.01-0.63 mgl-1), Zn (0-0.35 mgl-1), Cu (0.01-0.91 mgl-1), Cn (0.002-0.029 mgl-1) and Ni (0-0.002 mgl-1). Results, also, showed a quit great density of total viable bacterial count and indicator organisms including total Coli forms, fecal coli forms, Aeromonas spp., Staphylococcus spp. and Vibrio spp. It is concluded that water in Lake Manzala is highly damaged and the phenomena need more attention in order to reduce the pollution load that reaches the Mediterranean Sea.

Evaluation of bacterial quality of Oreochromis niloticus samples of Lake Manzala, Egypt

“…Heavy metals are especially toxic due to their ability to bind with proteins and prevent DNA replication [3]. The lake has been gradually transformed from a largely marine or estuarine environment to a eutrophic nearly fresh water system which can have significant negative ecological, health, social and economic impacts on human [4]. These result in poor water quality and reduction in the lake productivity of fish [5].…”

Histological Assessment of Gonadal Alteration in Wild Nile Tilapia Oreochromis niloticus Inhabiting Lake Manzala, Egypt

“…The Lake is exposed to high inputs of pollutants from industrial, domestic, and agricultural sources. Climate gases and large amounts of particulate matter, nutrients, bacteria, heavy metals, and toxic organics are transported to the Lake through the wastewater discharge (Ismail and Hettiarachchi, 2017). The Lake received about 7500 million cubic meters of untreated industrial, domestic and agricultural drainage water, discharged annually through six main drains; Bahr El-Baqer Drain, Hadous Drain, Ramsis Drain, El-Serw Drain, Matariya Drain and Faraskour Drain.…”

“…The Lake received about 7500 million cubic meters of untreated industrial, domestic and agricultural drainage water, discharged annually through six main drains; Bahr El-Baqer Drain, Hadous Drain, Ramsis Drain, El-Serw Drain, Matariya Drain and Faraskour Drain. This amount of wastewater was reduced to about 4000 million cubic meters after construction of El-Salam Canal (Abdel-Baky et al, 1998;El-Ghazali et al, 2015;Ismail and Hettiarachchi, 2017). The drains convey large amount of nutrients, especially from Bahr-El-Bakar, Ramsis and Hadous drains that are heavily contaminated by sewage and industrial wastewater (El-Ghazali et al, 2015).…”

Seasonal Variation of Metallic Contamination of Water and Sediments in Navigation Canal and Industrial Zone South Port Said, Egypt

“…This outlet allows an exchange of water between the Lake and the Mediterranean Sea. This makes the Northern portion of Lake to be characterized by high salinity [8]. El-Moselhy and Gabal [9] found that the highest values of metals were observed at stations influenced by various pollution sources such as harbours sewage and industrial drains.…”