Environmental Impact Assessment of Wastewater Disposal at the West Sohag Site, Egypt: A Sustainable Development Goals Perspective

1.0 Executive Summary

This report details an environmental impact assessment of the wastewater treatment and disposal site in West Sohag, Sohag Governorate, Egypt. Operational since 1990, the site’s effluent infiltration has led to significant groundwater contamination, posing a direct threat to several United Nations Sustainable Development Goals (SDGs). Using remote sensing and geochemical analysis, this study evaluates the extent of contamination, particularly from heavy metals, and its implications for public health (SDG 3), water quality (SDG 6), sustainable communities (SDG 11), and terrestrial ecosystems (SDG 15). Findings indicate that uncontrolled wastewater ponds, coupled with high soil permeability, have resulted in the leakage of contaminants into the Quaternary aquifer. Average heavy metal concentrations in groundwater exceeded safe limits, with a descending order of Zn > Cu > Pb > Cd. The study confirms a direct link between the disposal site and aquifer pollution, providing critical data for developing remediation strategies aligned with sustainable development principles.

2.0 Introduction: Wastewater Management and the Sustainable Development Agenda

Effective wastewater management is a cornerstone of sustainable urban development, directly impacting several SDGs. In developing nations, rapid urbanization and population growth place immense pressure on sanitation infrastructure, often leading to environmental degradation and public health crises. This situation critically undermines progress towards:

• SDG 6 (Clean Water and Sanitation): Inadequate sewage treatment leads to the discharge of pollutants into water bodies, contaminating essential groundwater resources.
• SDG 3 (Good Health and Well-being): Contaminated water is a primary vector for waterborne diseases such as cholera and typhoid and exposes populations to toxic heavy metals, which are recognized carcinogens.
• SDG 11 (Sustainable Cities and Communities): The failure to manage waste creates hazardous living conditions and compromises the long-term viability of urban and rural areas.

In Egypt’s Sohag Governorate, the reliance on unsuitable cesspools and the land application of treated effluent in the desert lowlands present significant environmental challenges. This study assesses the West Sohag disposal site to understand the environmental repercussions and inform management practices that align with global sustainability targets.

3.0 Study Area: Geological and Hydrogeological Context

3.1 Location and Geomorphology

The study was conducted in the Nile Valley, west of Sohag city, a region characterized by three primary geomorphological units:

1. The Eocene limestone plateau.
2. The low-land desert area, where the wastewater disposal site is located.
3. The Nile floodplain, comprising cultivated lands vital for local agriculture and livelihoods.

The disposal site’s location in the low desert zone, in close proximity to residential areas, agricultural lands, and the primary Quaternary aquifer, makes it a critical point of interest for assessing risks to both human and environmental health, central to achieving SDG 11 and SDG 15.

3.2 Hydrogeological Setting and Vulnerability

The primary water source in the region is the Quaternary aquifer, which is highly vulnerable to surface pollution. Key characteristics include:

• Composition: Primarily sand and gravel, covered by floodplain sediments.
• Thickness: Varies from 20 to 80 meters.
• Hydraulic Conductivity: Ranges from 0.29 to 3.72 m/day, indicating moderate to high permeability.
• Recharge Sources: Infiltration from irrigation canals and leakage from surface water bodies.

The high permeability of the soil and aquifer sediments means that surface contaminants, such as those from wastewater ponds, can rapidly infiltrate and pollute the groundwater, directly threatening the region’s progress towards SDG 6.

4.0 Methodology: An Integrated Approach to Contamination Monitoring

To assess the environmental hazards and their impact on SDG targets, a multi-faceted methodology was employed, combining remote sensing, fieldwork, and geochemical analysis.

4.1 Remote Sensing and GIS Analysis

Advanced geospatial techniques were used to monitor environmental changes and map land use, providing a clear picture of the pressures on local ecosystems (SDG 15) and community resources (SDG 11).

• Land Use Mapping: Landsat-8 imagery was used to classify the area into urban centers, agricultural lands, water courses, and barren lands, revealing significant expansion of urban and agricultural activities.
• Temporal Analysis: High-resolution Google Earth Pro time-series images (1990-2025) were analyzed to track the expansion of contaminated areas and uncontrolled wastewater ponds over time.

4.2 Field Sampling and Geochemical Investigation

Fieldwork focused on collecting groundwater samples to quantify the extent of chemical contamination, a key indicator for SDG 3 and SDG 6.

• Sample Collection: 50 groundwater samples were collected from private wells surrounding the West Sohag disposal site.
• Heavy Metal Analysis: Concentrations of Zinc (Zn), Cadmium (Cd), Lead (Pb), and Copper (Cu) were measured using an atomic absorption spectrophotometer (AAS).
• Bacteriological Analysis: Samples were tested for fecal coliform to assess sewage contamination and the risk of waterborne diseases.

5.0 Results and Analysis

5.1 Soil Permeability and Contaminant Transport

The textural analysis of sediments at the disposal site revealed a composition of muddy sand, silty sand, and sand-gravel. The hydraulic conductivity, averaging 38.9% porosity, was determined to be moderate to high. This physical characteristic facilitates the rapid downward migration of wastewater from surface ponds into the groundwater aquifer, exacerbating the pollution problem and creating a significant barrier to achieving SDG 6.

5.2 Land Use Change and Environmental Pressure

Remote sensing data revealed a substantial increase in contaminated areas over time. The expansion of agricultural and urban zones around the disposal site has intensified the environmental risks. Uncontrolled wastewater ponds have formed due to insufficient land for the volume of effluent, posing a direct threat to adjacent communities and ecosystems. This unsustainable land management practice conflicts with the objectives of SDG 11 and SDG 15.

5.3 Geochemical Evidence of Groundwater Contamination

The chemical analysis confirmed significant contamination of the Quaternary aquifer, directly impacting water safety and human health (SDG 3, SDG 6).

• Heavy Metal Concentrations: Average concentrations were found in the order of Zn (8.55 ppm) > Cu (0.421 ppm) > Pb (0.282 ppm) > Cd (0.207 ppm). Concentrations of Pb, Cd, and Zn in samples near the disposal site exceeded WHO permissible limits for drinking water.
• Spatial Distribution: Contamination levels were highest in the low desert zone near the wastewater ponds and decreased eastward towards the Nile floodplain. This gradient indicates the disposal site is the primary pollution source.
• Statistical Correlation: A very high correlation (coefficients >0.8) was found between all measured heavy metals (Pb, Cd, Cu, Zn), suggesting a common anthropogenic source, namely the wastewater effluent.
• Bacteriological Contamination: The presence of fecal coliform bacteria in groundwater samples confirmed sewage leakage, indicating a high risk of waterborne diseases.

6.0 Discussion: Implications for Sustainable Development

The findings from the West Sohag site highlight a critical failure in sustainable resource management. The continuous leakage of untreated and poorly treated wastewater into a vital aquifer directly contravenes the core principles of the SDGs.

• Threat to SDG 6: The contamination of the Quaternary aquifer compromises the availability of safe drinking water and sanitation for the local population. The current disposal method is unsustainable and actively degrades water quality.
• Impact on SDG 3: Elevated levels of carcinogenic heavy metals and pathogenic bacteria in the groundwater supply pose severe, long-term health risks to communities relying on this water for domestic and agricultural use.
• Challenge to SDG 11 and SDG 15: The haphazard expansion of wastewater ponds and the resulting soil and water pollution degrade terrestrial ecosystems and create unsafe living environments in a region experiencing rapid urban and agricultural growth.

The time-series analysis showing a 55% increase in wastewater ponds alongside a 75% increase in urban areas illustrates a growing crisis. Without intervention, the environmental and health consequences will escalate, moving the region further away from its sustainability targets.

7.0 Conclusions and Strategic Management Framework

The investigation of the West Sohag wastewater disposal site confirms that it is an unsuitable location for land application of wastewater and a significant source of environmental hazard. The contamination of the Quaternary aquifer with heavy metals and bacteria presents an urgent threat to public health and ecological stability. To address these challenges and align with the Sustainable Development Goals, a strategic management framework is proposed:

7.1 Immediate Actions for Public Health and Safety (SDG 3)

1. Provide alternative, safe water supplies for affected communities.
2. Conduct health screenings for populations exposed to contaminated water.
3. Launch public awareness campaigns on the risks of using water from contaminated wells and ponds.

7.2 Remediation and Monitoring (SDG 6 & SDG 15)

1. Implement a continuous water quality monitoring program for groundwater wells.
2. Initiate remediation strategies, such as pump-and-treat systems for highly contaminated zones and the establishment of phytoremediation barriers.
3. Enforce mandatory pre-treatment of all industrial and municipal effluent before disposal.

7.3 Long-Term Sustainable Planning (SDG 11 & SDG 12)

1. Develop and enforce land-use zonation plans to prevent high-risk activities near vulnerable aquifers.
2. Construct engineered buffer zones and liners for all wastewater ponds and treatment basins to prevent seepage.
3. Establish a multi-agency coordination network (health, water, agriculture, environment) to ensure integrated and sustainable management of water and waste resources.

Adopting this framework is essential to mitigate the existing damage and prevent future contamination, thereby steering the Sohag Governorate towards a more sustainable and resilient future.

1. Which SDGs are addressed or connected to the issues highlighted in the article?

1. SDG 3: Good Health and Well-being

   • The article directly connects improper wastewater disposal to significant public health risks. It mentions that contaminated ponds “could have catastrophic health consequences” and facilitate the spread of “waterborne diseases like cholera, dysentery, and typhoid.” The contamination of groundwater with heavy metals like Lead (Pb), Cadmium (Cd), Zinc (Zn), and Copper (Cu), which are categorized as “human carcinogens,” further underscores the threat to human health.

2. SDG 6: Clean Water and Sanitation

   • This is the central theme of the article. It focuses on the failure of wastewater management, leading to the “contamination of water bodies” and specifically the “groundwater aquifer system.” The study assesses “sewage water leakage” and the infiltration of untreated effluent, which directly compromises the availability of clean water, a critical issue as “Groundwater is the key source of drinkable water in several metropolitan areas.”

3. SDG 11: Sustainable Cities and Communities

   • The problem is framed within the context of a “densely populated” region facing challenges from “fast population expansion, industrialization, and urbanization.” The article highlights that the wastewater disposal site is in “close proximity to essential infrastructure and service components, including residential neighborhoods,” making waste management a critical component of sustainable urban development.

4. SDG 12: Responsible Consumption and Production

   • The article addresses the lifecycle of waste, specifically the “improper wastewater disposal” and the release of hazardous materials into the environment. The presence of “heavy metal contamination in aquatic environments” is a direct result of production and consumption patterns that lack environmentally sound management of waste, as called for by this goal.

5. SDG 15: Life on Land

   • The research highlights the adverse effects on terrestrial ecosystems. The leakage of contaminated wastewater poses a risk to the “ecosystem” through “soil and groundwater pollution.” The article notes that “soil, crops, and water supplies are contaminated chemically and bacteriologically,” which constitutes land degradation and harms the local environment.

2. What specific targets under those SDGs can be identified based on the article’s content?

1. SDG 3: Good Health and Well-being

   • Target 3.3: End the epidemics of water-borne diseases. The article’s concern about the spread of “waterborne diseases like cholera, dysentery, and typhoid” due to contaminated water directly relates to this target.
   • Target 3.9: Substantially reduce the number of deaths and illnesses from hazardous chemicals and water and soil pollution. The core of the study is the assessment of groundwater contamination by “heavy metals” (Pb, Cd, Zn, Cu) and “bacteriologically” contaminated wastewater, which are hazardous substances causing severe health risks.

2. SDG 6: Clean Water and Sanitation

   • Target 6.1: Achieve universal and equitable access to safe and affordable drinking water. The contamination of the “Quaternary aquifer,” which serves as the “primary source of water for these projects” (development, urbanization), directly threatens the safety and accessibility of drinking water.
   • Target 6.3: Improve water quality by reducing pollution and halving the proportion of untreated wastewater. The article explicitly details the failure to meet this target, describing how “Excess raw wastewater accumulates on the ground surface at current operating sites, forming large, uncontrolled ponds” and leads to “sewage water leaking into the groundwater aquifer.”
   • Target 6.6: Protect and restore water-related ecosystems. The study’s objective to understand the “environmental impacts of the wastewater disposal site on the groundwater aquifer system” is directly aligned with the protection of this critical water-related ecosystem.

3. SDG 11: Sustainable Cities and Communities

   • Target 11.6: Reduce the adverse per capita environmental impact of cities, including waste management. The article discusses “Wastewater management is a serious challenge in metropolitan regions” due to population growth and urbanization, and the study assesses the environmental impact of this municipal waste.

4. SDG 12: Responsible Consumption and Production

   • Target 12.4: Achieve the environmentally sound management of chemicals and all wastes. The article’s focus on the “improper wastewater disposal” and the resulting “heavy metal contamination” highlights a failure in the sound management of waste, leading to adverse impacts on “human health and the environment.”

5. SDG 15: Life on Land

   • Target 15.1: Ensure the conservation and sustainable use of terrestrial and inland freshwater ecosystems. The pollution of the “groundwater aquifer” and surrounding “soil” represents a direct threat to these ecosystems.
   • Target 15.3: Combat desertification and restore degraded land and soil. The chemical and bacteriological contamination of soil mentioned in the article is a form of land degradation that this target aims to reverse.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

1. Indicators for SDG 6 (Clean Water and Sanitation)

   • Indicator 6.3.1 (Proportion of wastewater safely treated): The article implies this is very low. The formation of “large, uncontrolled ponds” from “excess raw wastewater” and the fact that “insufficient land is available to accommodate the projected quantities of wastewater” are clear qualitative indicators of a lack of safe treatment.
   • Indicator 6.3.2 (Proportion of bodies of water with good ambient water quality): The article provides direct, quantitative data showing poor water quality. Specific measurements are given for heavy metal concentrations: “Average heavy metal concentrations in the analyzed groundwater decreased from Zn > Cu > Pb > Cd, with mean values of 8.55 > 0.421 > 0.282 > 0.207 ppm, respectively.” Furthermore, the “bacteriological analysis… showed a positive indication of the presence of fecal coliform bacteria,” another direct measure of water quality.

2. Indicators for SDG 3 (Good Health and Well-being)

   • Indicator 3.9.2 (Mortality rate attributed to unsafe water, unsafe sanitation): While the article does not provide mortality rates, it provides data on the risk factors. The measured presence of “fecal coliform” and heavy metals like lead and cadmium above “maximum allowable limits” in drinking water sources are direct indicators of exposure to unsafe water.

3. Indicators for SDG 12 (Responsible Consumption and Production)

   • The concentrations of specific hazardous chemicals in the environment are key indicators. The article’s detailed geochemical analysis and mapping of Zn, Pb, Cd, and Cu concentrations in the groundwater serve as direct measurements of the release of these pollutants into the environment, which Target 12.4 aims to reduce.

4. Indicators for SDG 15 (Life on Land)

   • The article uses remote sensing to monitor the extent of environmental damage. The finding that “the contaminated areas increased substantially” and the use of “Google Earth time series images” to track the growth of “wastewater ponds” from 1990 to 2025 serve as indicators for measuring the extent of land and ecosystem degradation.

4. Create a table with three columns titled ‘SDGs, Targets and Indicators” to present the findings from analyzing the article.

Source: nature.com