الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Constructed wetlands are artificial transitional zones between terrestrial and aquatic system serving ecological functions such as fish, wildlife, waterfowl and aquatic plants. They also trap sediments and pollutants, cycle nutrients, and reuse treated water in agriculture. In Egypt, several drains are severely polluted by domestic, industrial, and agriculture sources. Bahr ElBaqar drain is one of those polluted drains that discharge to Lake Manzala. Treating and recycling drainage water in irrigation is a strategic Egyptian target. Egypt has some ongoing plans for the protection of Lake Manzala and the Mediterranean. For this reason, it is essential to seek lowcost wastewater treatment alternative that is convenient for large quantities of water. Constructed wetland is an attractive alternative for treatment of drainage water before reaching Northern Lakes due to its low energy input and labour cost. A demonstration wetland project has been established close to Lake Manzala in order to treat part of the polluted drainage waters. The objective of this study is to evaluate the performance of the constructed wetland in treating polluted drainage water to the limit that can safely protect Lake Manzala and the Mediterranean Sea against pollution. The study of hydraulic and flow behaviours of constructed wetland during pollutant removal processes have been investigated. Two mathematical models depending on the mixed and partially mixed flow assumptions are applied to compute pollutant removal inside the wetland cells. A tracer test study is conducted to measure the actual hydraulic detention time (HDT) of flow in the wetland in a comparison with the design HDT as an efficiency performance indicator. Moreover, a wetland treatment performance model (PREWet 2.4) is applied to determine the pollutant concentrations in the treated water based on the plug flow and mixed flow hypotheses. Results of the study gave that the demonstration constructed wetland managed to treat BOD, TSS, NH4, NO3, TC, FC, and Fe in the drainage water to the limit that can protect Lake Manzala from pollution hazards. Tracer study showed that the measured value of HDT was higher than the designed value of HDT. In addition, both mixed flow and partially mixed flow models can estimate pollutant removals inside wetland cells. The results of PREWet 2.4 model on the wetland are relatively close to the measured field data in most pollutants at wetland outlet.