River Water Quality and Quantity Determinants in a Developing Country

Abstract Developing countries rely to a large extent on international donors to improve water security. Yet, international interventions often end up with low efficiency impacts because of the lack of a priori comprehensive projections. With this in mind, this paper presents a scenario-based methodology to forecast river water quantity and quality in a common multi-stressor situation, that is combined impact of climate change, population growth and wastewater discharge. As an illustrative case, El Kalb River basin, in Lebanon, was simulated under four scenarios up to year 2050, using Water Evaluation and Planning (WEAP) model. The observed trends indicate that mean annual streamflow and flow to groundwater could decrease by around 10 to 23% each due to climate change, while water demand is expected to increase by 16 to 32%. As to water quality, the maximum BOD of 68 mg/L (in 2019) can be decreased by introducing wastewater treatment (starting 2021 as planned by national authorities) to 44 mg/L, only to increase again to 63 mg/L in 2050 due to population growth. Considering climate change, water quality is expected to deteriorate further and the maximum BOD would reach 118 mg/L and 147 mg/L in 2050 under RCP 4.5 and RCP 8.5 scenarios, respectively. Even though the planned wastewater treatment facilities would reduce BOD by 34%, it was shown that the river would never meet water standards – under any of the proposed scenarios. The approach adopted in this paper is recommended for quantification of the efficiency of river protection plans in developing areas.

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Hydrological Simulation for Predicting the Future Water Quality of Adyar River, Chennai, India

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16234597 ◽

2019 ◽

Vol 16 (23) ◽

pp. 4597 ◽

Cited By ~ 1

Author(s):

Kumar ◽

Dasgupta ◽

Ramaiah ◽

Avtar ◽

Johnson ◽

...

Keyword(s):

Climate Change ◽

Water Quality ◽

Population Growth ◽

Oxygen Demand ◽

Surface Water Quality ◽

Global Changes ◽

Weap Model ◽

Hydrological Simulation ◽

The Future

Just a few decades ago, Adyar River in India’s city of Chennai was an important source of water for various uses. Due to local and global changes (e.g., population growth and climate change), its ecosystem and overall water quality, including its aesthetic value, has deteriorated, and the water has become unsuitable for commercial uses. Adverse impacts of excessive population and changing climate are expected to continue in the future. Thus, this study focused on predicting the future water quality of the Adyar river under “business as usual” (BAU) and “suitable with measures” scenarios. The water evaluation and planning (WEAP) simulation tool was used for this study. Water quality simulation along a 19 km stretch of the Adyar River, from downstream of the Chembarambakkam to Adyar (Bay of Bengal) was carried out. In this analysis, clear indication of further deterioration of Adyar water quality by 2030 under the BAU scenario was evidenced. This would be rendering the river unsuitable for many aquatic species. Due to both climate change (i.e., increased temperature and precipitation) and population growth, the WEAP model results indicated that by 2030, biochemical oxygen demand (BOD) and Escherichia coli concentrations will increase by 26.7% and 8.3%, respectively. On the other hand, under the scenario with measures being taken, which assumes that “all wastewater generated locally will be collected and treated in WWTP with a capacity of 886 million liter per day (MLD),” the river water quality is expected to significantly improve by 2030. Specifically, the model results showed largely reduced concentrations of BOD and E. coli, respectively, to the tune of 74.2% and 98.4% compared to the BAU scenario. However, even under the scenario with measures being taken, water quality remains a concern, especially in the downstream area, when compared with class B (fishable surface water quality desirable by the national government). These results indicate that the current management policies and near future water resources management plan (i.e., the scenario including mitigating measures) are not adequate to check pollution levels to within the desirable limits. Thus, there is a need for transdisciplinary research into how the water quality can be further improved (e.g., through ecosystem restoration or river rehabilitation).

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Impacts of Climate Change and Population Growth on River Nutrient Loads in a Data Scarce Region: The Upper Awash River (Ethiopia)

Sustainability ◽

10.3390/su13031254 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1254

Author(s):

Gianbattista Bussi ◽

Paul G. Whitehead ◽

Li Jin ◽

Meron T. Taye ◽

Ellen Dyer ◽

...

Keyword(s):

Climate Change ◽

Water Pollution ◽

Water Quality ◽

Population Growth ◽

River Water ◽

Addis Ababa ◽

River Water Quality ◽

Nutrient Concentrations ◽

Nutrient Loads ◽

The Impact

Assessing the impact of climate change and population growth on river water quality is a key issue for many developing countries, where multiple and often conflicting river water uses (water supply, irrigation, wastewater disposal) are placing increasing pressure on limited water resources. However, comprehensive water quality datasets are often lacking, thus impeding a full-scale data-based river water quality assessment. Here we propose a model-based approach, using both global datasets and local data to build an evaluation of the potential impact of climate changes and population growth, as well as to verify the efficiency of mitigation measures to curb river water pollution. The upper Awash River catchment in Ethiopia, which drains the city of Addis Ababa as well as many agricultural areas, is used as a case-study. The results show that while decreases in runoff and increases in temperature due to climate change are expected to result in slightly decreased nutrient concentrations, the largest threat to the water quality of the Awash River is population growth, which is expected to increase nutrient loads by 15 to 20% (nitrate) and 30 to 40% (phosphorus) in the river by the second half of the 21st century. Even larger increases are to be expected downstream of large urban areas, such as Addis Ababa. However, improved wastewater treatment options are shown to be efficient in counteracting the negative impact of population growth and returning water pollution to acceptable levels.

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Modelling multiple threats to water security in the Peruvian Amazon using the WaterWorld policy support system

Earth System Dynamics ◽

10.5194/esd-5-55-2014 ◽

2014 ◽

Vol 5 (1) ◽

pp. 55-65 ◽

Cited By ~ 8

Author(s):

A. J. J. van Soesbergen ◽

M. Mulligan

Keyword(s):

Climate Change ◽

Population Growth ◽

Oil And Gas ◽

Water Security ◽

Policy Support ◽

Water Quantity ◽

Urban Migration ◽

Gas Extraction ◽

Peruvian Amazon ◽

Rural Urban Migration

Abstract. This paper describes the application of WaterWorld (www.policysupport.org/waterworld) to the Peruvian Amazon, an area that is increasingly under pressure from deforestation and water pollution as a result of population growth, rural-to-urban migration and oil and gas extraction, potentially impacting both water quantity and water quality. By applying single and combined plausible scenarios of climate change, deforestation around existing and planned roads, population growth and rural–urban migration, mining and oil and gas exploitation, we explore the potential combined impacts of these multiple changes on water resources in the Peruvian Amazon.

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Microbiological requirements for safe drinking water production at a large river impacted by human wastewater: a scenario analysis

10.5194/egusphere-egu21-14863 ◽

2021 ◽

Author(s):

Katalin Demeter ◽

Julia Derx ◽

Jürgen Komma ◽

Juraj Parajka ◽

Jack Schijven ◽

...

Keyword(s):

Climate Change ◽

Drinking Water ◽

Wastewater Treatment ◽

Population Growth ◽

Water Supply ◽

Large River ◽

Wastewater Management ◽

Reference Scenario ◽

Safe Drinking Water

Background: Rivers are important sources for drinking water supply, however, they are often impacted by wastewater discharges from wastewater treatment plants (WWTP) and combined sewer overflows (CSO). Reduction of the faecal pollution burden is possible through enhanced wastewater treatment or prevention of CSOs. Few methodological efforts have been made so far to investigate how these measures would affect the long-term treatment requirements for microbiologically safe drinking water supply under future changes.Objectives: This study aimed to apply a new integrative approach to decipher the interplay between the effects of future changes and wastewater management measures on the required treatment of river water to produce safe drinking water. We investigated scenarios of climate change and population growth, in combination with different wastewater management scenarios (i.e., no upgrades and upgrades at WWTPs, CSOs, and both). To the best of our knowledge, this is the first study to investigate this interplay. We focussed on the viral index pathogens norovirus and enterovirus and made a cross-comparison with a bacterial and a protozoan reference pathogen (Campylobacter and Cryptosporidium).Methods: We significantly extended QMRAcatch (v1.0 Python), a probabilistic-deterministic model that combines virus fate and transport modelling in the river with quantitative microbial risk assessment (QMRA). To investigate the impact of climatic changes, we used a conceptual semi-distributed hydrological model and regional climate model outputs to simulate river discharges for the period 2035 &#8211; 2049. We assumed that population growth leads to a corresponding increase in WWTP discharges. QMRAcatch was successfully calibrated and validated based on a four-year dataset of a human-associated genetic MST marker and enterovirus. The study site was the Danube in Vienna, Austria.Results: In the reference scenario, approx. 98% of the enterovirus and norovirus loads at the study site (median: 1010 and 1013 N/d) originated from WWTP effluent, while the remainder was via CSO events. The required log reduction value (LRV) to produce safe drinking water was 6.3 and 8.4 log10 for enterovirus and norovirus. Future changes in population size, river flows and CSO events did not affect these treatment requirements, and neither did the prevention of CSOs. In contrast, in the scenario of enhanced wastewater treatment, which showed lower LRVs by 2.0 and 1.3 log10, climate-change-driven increases in CSO events had a considerable impact on the treatment requirements, as they affected the main pollution source. Preventing CSOs and installing enhanced treatment at the WWTPs together had the most significant positive effect with a reduction of LRVs by 3.9 and 3.8 log10 compared to the reference scenario.Conclusions: The integrative modelling approach was successfully realised. The simultaneous consideration of source apportionment and concentrations of the reference pathogens were found crucial to understand the interplay among the effects of climate change, population growth and pollution control measures. The approach was demonstrated for a study site representing a large river impacted by WWTP and CSO discharges, but is applicable at other sites to support long term water safety planning.

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Identifying Pollutants in the Siret River Basin by Applying New Assessment Tools on Monitoring Data: the Correlation of Land Use and Physicochemical Parameter of Water Quality Analysis

Present Environment and Sustainable Development ◽

10.2478/pesd-2014-0021 ◽

2014 ◽

Vol 8 (2) ◽

pp. 5-19

Author(s):

Andreea Mănescu ◽

Luca Mihail ◽

Mihalache Raluca

Keyword(s):

Water Quality ◽

Land Use ◽

Wastewater Treatment ◽

River Water ◽

Municipal Wastewater ◽

Pollution Source ◽

Assessment Tools ◽

Quality Analysis ◽

Water Supply Systems ◽

Municipal Wastewater Treatment

Abstract The Siret River are used as raw water source for different municipal water supply systems, yet the Siret River are used as receiving bodies by some inhabitants and industry. In the study the quality of the Siret River water was determinate using a Water Quality Index (WQI). Results are presented from a field study performed on the Bistrita, Moldova, Suceava, Siret, Şomuzu Mare, Trotuş and Tributary River in the study area Siret Basin Romania. The main objective of this study was to determine is to find correlations land use to indicators physical-chemical of water quality, to investigate pollution source is more responsible for river water quality. This is of interest not only research context, but also for supporting and facilitating the application analysis postullend in the Water Framework Directive (WFD) (2000/60/CE) for the establishment of programmers of measures. For this purpose a slightly impact pollution source municipal wastewater treatment, land uses, urban, forest, agriculture and mining was selected and intensively monitored during six years January 2006 - December 2011, sampling was determined to meet the WFD standards for confidence in twenty two different control section of the Siret Basin. The main measures to reduce emissions to the Siret River were calcium, ammonium, sulfate, residue fixed (RF), sodium, chloride, free detergent and municipal wastewater treatment, concentrated on point emission. The main contributor to diffuse this parameters increased when more percentage of land was dedicated to industry and urban and less to forest and mining.

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Water quality management in the context of future climate and development changes: a South African case study

Journal of Water and Climate Change ◽

10.2166/wcc.2016.138 ◽

2016 ◽

Vol 7 (4) ◽

pp. 775-787 ◽

Cited By ~ 1

Author(s):

A. S. Slaughter ◽

S. K. Mantel ◽

D. A. Hughes

Keyword(s):

Climate Change ◽

Water Quality ◽

Water Resources ◽

Water Quality Management ◽

Nutrient Inputs ◽

Weap Model ◽

Change Models ◽

Water Quality Simulation ◽

Model Driven ◽

Quality Decision

Globally, water resources are being over-utilised; a situation exacerbated by degenerating water quality of rivers. To achieve sustainable management of water resources, uncertainty under climate change and development must be considered. A companion study was the first to incorporate uncertainty within water resources development scenario modelling for a catchment in South Africa using the Water Evaluation and Planning (WEAP) model. That study is extended in the current study by considering water quality in the form of nutrients and salinity. The WEAP model was calibrated against available observed data for the period 1999–2005. Using the calibrated WEAP model, driven by flow predicted using downscaled climate change models and projected future development, water quality was simulated for the years 2046–2065. Future simulations indicated marginally increased dilution capacity as well as increased nutrient inputs. It is evident that WEAP suffers major limitations in its water quality simulation capacity. Adaptive management along with continual monitoring as a strategy to cope with uncertainty associated with climate change and development is recommended. The shortcomings identified within WEAP in the current study were the motivation for the development of a new water quality decision support system specific to the requirements of water management in southern Africa.

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River water quality response under hypothetical climate change scenarios in Tunga-Bhadra river, India

Hydrological Processes ◽

10.1002/hyp.8057 ◽

2011 ◽

Vol 25 (22) ◽

pp. 3373-3386 ◽

Cited By ~ 41

Author(s):

S. Rehana ◽

P. P. Mujumdar

Keyword(s):

Climate Change ◽

Water Quality ◽

River Water ◽

River Water Quality ◽

Climate Change Scenarios ◽

Quality Response

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Sustainable Water Provision

Green Technologies ◽

10.4018/978-1-60960-472-1.ch714 ◽

2011 ◽

pp. 1768-1781

Author(s):

Shinyi Lee ◽

Tan Yigitcanlar ◽

Prasanna Egodawatta ◽

Ashantha Goonetilleke

Keyword(s):

Climate Change ◽

Economic Growth ◽

Population Growth ◽

Water Resource Management ◽

Water Security ◽

Policy Makers ◽

Global Challenge ◽

Current Water ◽

Water Provision ◽

Growth Changes

As a result of rapid urbanisation, population growth, changes in lifestyle, pollution and the impacts of climate change, water provision has become a critical challenge for planners and policy-makers. In the wake of increasingly difficult water provision and drought, the notion that freshwater is a finite and vulnerable resource is increasingly being realised. Many city administrations around the world are struggling to provide water security for their residents to maintain lifestyle and economic growth. This chapter reviews the global challenge of providing freshwater to sustain lifestyles and economic growth, and the contributing challenges of climate change, urbanisation, population growth and problems in rainfall distribution. The chapter proceeds to evaluate major alternatives to current water sources such as conservation, recycling and reclamation, and desalination. Integrated water resource management is briefly looked at to explore its role in complementing water provision. A comparative study on alternative resources is undertaken to evaluate their strengths, weaknesses, opportunities and constraints, and the results are discussed.

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