The rivers of Dhaka, Bangladesh, suffer high levels of pollution from untreated sewage and industrial effluent. To address this, over the next 20 years, the government is planning to install 12 large Sewage Treatment Plants (STPs) across the Dhaka River System. This paper applies a water quality model to assess the efficacy of this planned investment. The model suggests that the STPs will improve water quality in the most densely populated areas of the city along the Turag and Buriganga rivers, and in some other parts of the city (Tongi Khal). However, future upgrades will be needed to improve dissolved oxygen levels more widely, due to predicted population growth. Policies to reduce industrial pollution should also be pursued.
Research theme
Hydrologic Extremes in a Changing Climate: a Review of Extremes in East Africa
This review presents recent research on drivers and typologies of climate extremes across different East African geographies. Droughts and floods remain the major challenges of the region. There are improvements in forecasting these extremes, but further research is required to improve understanding of key drivers and improve information provision for risk-based decision-making.
Environmental isotopes (δ 18O–δ 2H, 222Rn) and electrical conductivity in backtracking sources of urban pipe water, monitoring the stability of water quality and estimating pipe water residence time
In this paper, environmental isotopes and electrical conductivity are used to investigate water quality variations in the urban piped water network of Addis Ababa, Ethiopia. The isotopic signature of the water allows the back-tracking of tap water to its source and also provides insights into pipe water residence time for groundwater-sources supplies. The tracers reveal that 50% of the city relies on groundwater, and that groundwater-sourced water supplies show the highest water quality instability. One important cause of water quality variation in the city is borehole stoppages and reconnection as a result of electricity cuts.
Evaluating the effects of geochemical and anthropogenic factors on the concentration and treatability of heavy metals in Awash River and Lake Beseka, Ethiopia: arsenic and molybdenum issues
This study assesses heavy metal and pollution sources within the Awash River Basin, in Ethiopia. In this region, significant urbanization and industrialization have caused pollutants to enter water bodies on a large scale. After finding high levels of heavy metals across surface water sampling stations, the study advocates for increased efforts towards water security within the Addis Ababa and Awash watershed region.
Story of Change: Progress to deliver safe drinking water services to 100 million rural people by 2030
In 2021, REACH and RWSN led a global diagnostic survey to identify rural water service providers in 68 countries with interest or existing experience in results-based funding. Results suggested that up to 68 service providers in 28 countries could potentially provide results-based services to 5 million rural people. Subsequently, the Uptime Catalyst Facility has expanded results-based contracts for reliable water services serving 1.5 million rural people in 7 countries in 2022 to over 5 million people in 17 countries, including Latin America and India in 2024.
Evaluating the structures and arrangements of water institutions to include in-stream modeling for water quality management and control pollution: Insights from the Awash Basin, Ethiopia
In sub-Saharan regions, human activities are causing stream water quality to decline. This study assesses stream water quality issues in the Awash Basin of Ethiopia, identifying key sources of land-based pollutants. Applicable models with the capability of simulating the Awash streams are presented, and recommendations towards improved use of water quality modelling for development planning by Awash Basin institutions are made.
Information synthesis to identify water quality issues and select applicable in-stream water quality model for the Awash River basin in Ethiopia: A perspective from developing countries
In-stream water quality models can help prepare effective planning strategies to tackle problems with stream water quality and understand pollutant dynamics in stream systems. In this study, water quality issues in the Awash Basin were reviewed to select an applicable in-stream model to support local model practitioners in creating improvement in water quality management. QUAL2KW and INCA models are found more applicable for the present conditions, while the WASP model may be useful to conduct detailed analysis.
Opportunities to advance water safety through regulation of rural water services
Despite improved access to water supply systems globally, safe drinking water continues to limit progress towards Sustainable Development Goal 6.1. In particular, there is a disparity between access to uncontaminated water in rural and urban areas, with the former significantly lagging behind. In this discussion paper, researchers and practitioners in rural drinking water provision, management and regulation from Bangladesh, Kenya, England and Wales identify key aspects to advance regulation for rural drinking water services.
Global high-resolution drought indices for 1981–2022
Droughts are one of the most complex and devastating natural disasters and high-resolution data has proven essential in helping monitor their characteristics. This study has developed four high-resolution drought records based on the standardized precipitation evaporation index (SPEI) from 1981–2022. These datasets provide greater insight into drought patterns on varying scales, with potential benefits for the development of site-specific adaptation measures.
Assessing heavy metal contamination using biosensors and a multi-branch Integrated Catchment Model in the Awash River Basin, Ethiopia
The Awash River Basin in Ethiopia faces rising heavy metal concentrations due to poor wastewater management and loose enforcement of regulations around effluent discharge. Acute toxicity of surface and wastewater samples was measured using new molecular biosensor technology based on engineered luminescent bacteria. A multi-branch Integrated Catchment model (INCA) simulating tannery discharge under different treatment scenarios indicates that a 50% reduction in effluent concentrations could produce a 20 to 50% reduction in heavy metal concentration in the river over two years.
