This paper aims to propose a methodological framework for quantifying the reduction and increase of health risks associated with urban wastewater systems. A risk assessment model was used to quantify reduction in disease burden while a life cycle assessment approach was used to quantify increasing risks by environmental loading. Disability adjusted life years (DALYs) was used to quantify health risks. This framework was applied to a hypothetical watershed to evaluate health risks by installation of wastewater treatment systems. In this hypothetical case, 55 DALYs per year of health risk would be reduced for 200,000 people in the downstream community by constructing wastewater systems for 200,000 people, while a range from 1.9 to 22 DALYs per year of health risks would be generated by materials and energy consumption for construction and operation of wastewater systems. However, this result would significantly change, depending on the parameters used in this analysis. The proposed methodology should be improved to obtain more precise results, but it will suggest useful information to discuss the overall effects due to the installation of various types of urban wastewater systems.

Although significant progress has been achieved in the field of environmental impact assessment in many engineering disciplines, the impact of wastewater treatment plants has not yet been well integrated. In light of this remarkable scientific progress, the outputs of the plants as treated water and clean sludge have become potential sources of irrigation and energy, not a waste. The aim of this study is to assess the environmental impacts of upgrading the wastewater treatment plants from primary to secondary treatment. The Lifecycle Assessment Framework (ISO 14040 and 14044) was applied using GaBi Software. Abu Rawash wastewater treatment plant (WWTP) has been taken as a case study. Two scenarios were studied, Scenario 1 is the current situation of the WWTP using the primary treatment units and Scenario 2 is upgrading the WWTP by adding secondary treatment units. The study highlighted the influence and cumulative impact of upgrading all the primary WWTPs in Egypt to secondary treatment. With the high amount of energy consumed in the aeration process, energy recovery methods were proposed to boost the circular economy concept in Abu Rawash WWTP in order to achieve optimal results from environmental and economic perspectives.

Nile Delta Lagoons have been formed 7000 years before the present. The lagoons were aqua-cultural and ecological keystones for the early Egyptian agricultural civilization. The water quality of Nile Delta Lagoons has been deteriorated with the economic development, population rapid increase, and the related industrialization, which exert high pressure on the surrounding environment. The 4 lagoons (1) Maryut, (2) Edku, (3) Burullus, and (4) Manzala are large is surface area, shallow in depth and located on the Nile Delta that receive great amounts of agricultural drainage, sewage, and industrial effluents before discharging into the Mediterranean Sea. The aim of this study is to monitor and assess the water and sediment quality of the lagoons. In light of this assessment, it was found that excessive nutrients are discharged into these lagoons causing severe eutrophication. In addition, relatively low values of dissolved oxygen were recorded causing fish mortality in the lagoons which amplifies in summer as the temperature increases. The article also examined the physical and biological parameters in addition to the chemical concentration of trace metals (Zn, Fe, Pb, Mn, Cr, and Cd) in the water and sediment samples that were collected from the 4 lagoons. High values of biological oxygen demand, chemical oxygen demand, total coliform, fecal coliform, fecal streptococci, ammonia (NH3), total nitrogen, and total phosphorus were recorded. In addition, high concentrations of trace metals were found in the water and sediments of the 4 lagoons.

Indiscriminate dumping of solid wastes and the resulting groundwater contamination is a major issue, especially for developing countries. The main objective of this paper is to develop a groundwater mass transport model in order to study the effect of an open solid waste dumpsite on the water quality of water resources within the region around it. The harmful effects of indiscriminate solid wastes disposal by open dumping, which is still followed in many developing countries around the world, is highlighted. Abu Zaabal dumpsite; which is located in Qalyubiyah Governorate, Egypt; receives huge amounts of wastes daily causing leachate generation that percolates deep into the soil and polluting the shallow aquifer. The Groundwater Modeling System (GMS) software was used to model the groundwater flow and mass transport, using data collected from the site investigation and literature historical data available. Of the several contaminants measured in the site, six critical contaminants; namely Total Dissolved Solids (TDS), Lead, Boron, Nitrate, Manganese and Chemical Oxygen Demand (COD); were chosen to be modeled. The developed model was used to simulate the six contaminants using a transient-state model and concentration values for two different scenarios. Scenario-1 assumes that the dumpsite will be active until 2080, whereas Scenario-2 represents imminent closure of the dumpsite. The model results of each contaminant were calculated over 100-year interval, from 1980 until 2080, and the results of 2080 were presented. The results showed that the dumpsite had a major impact on the nearby water bodies, Abu Zaabal ponds and Belbais Drain. Moreover, the closure of the dumpsite showed that the maximum concentration of the majority of the considered contaminants was decreased by approximately 60–65%.

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