Water and the UN sustainable development goals

Water is essential for life, but we need to balance human needs with those of the environment on which we depend for our wellbeing, our health and much of our wealth. Not all of us are lucky enough to have access to adequate water resources and services linked to water, such as readily available low-cost drinking water and sanitation systems. According to the World Health Organization and United Nations Children’s Fund (WHO/UNICEF), hundreds of millions of people are still without access to safely managed drinking water and sanitation services. Their Joint Monitoring Programme (JMP) report, Progress on Drinking Water, Sanitation and Hygiene 2000–2020, found that although considerable progress has been made in achieving universal access to basic water services, the proportion of improved water sources that are accessible, available and free from contamination varies widely between countries. This indicates that many countries are facing a challenge to meet the Sustainable Development Goal (SDG) target for safely managed services. In addition, despite increasing the rural coverage of safely managed water services in some countries, and in other countries this coverage is similar to the urban coverage, there is a huge gap in terms of water quality. Many aquatic ecosystems (freshwater, brackish and oceanic) also are under threat with knockon consequences for humanity. Large quantities of inadequately treated or untreated wastewater are still being discharged into our surface, ground and coastal waters. The WHO reports that at least 2 billion people globally consume water from a source contaminated with faeces. Faecal contamination in the water supply system, whether rudimentary or complex, is a major cause of infectious diseases such as cholera, typhoid fever, diarrhoea, dysentery, hepatitis A and polio. As a result, 1.2 million people die every year from water related diseases. According to the Global Water Institute, in low- and middle-income countries, almost 50% of the population can link health problems to waterborne diseases. In addition, emergent pollutants such as microplastics, antibiotics, per- and polyfluoroalkyl substances (PFAS) and their degradation products found in water sources and in the environment pose a health risk to humans and animals

Groundwater hydrodynamics of an Eastern Africa coastal aquifer, including La Niña 2016–17 drought

In 2016–17 much of East Africa was affected by a severe drought which has been attributed to Indian Ocean Dipole and El Niño Southern Oscillation conditions. Extreme events such as this have immediate and knock-on effects on water availability for household, agricultural and industrial use. Groundwater resources can provide a buffer in times of drought, but may themselves be stressed by reduced recharge and increased usage, posing significant challenges to groundwater resource management. In the context of East Africa, groundwater management is also hampered by a lack of information on aquifer characteristics. With the aim of addressing this knowledge gap, this study shows the hydrogeological behaviour before and during La Niña 2016/17 drought in southern coastal Kenya on a groundwater system which sits within a geological structure which is representative of an important portion of the East African coast. Diverse hydrochemical and isotopic campaigns, as well as groundwater head variation measurements, were carried out to study the groundwater hydrodynamics and thus characterize the aquifer system under climatic conditions before and during the La Niña event. This information is complemented with an estimation of changes in local recharge since 2012 using local data sets. The main consequence of the drought was a 69% reduction of recharge compared to an average climatic year. There was reduced recharge during the first rainy season (April–June) and no recharge during the second wet season (October–December). There was a concurrent increase in seawater intrusion even during the wet season.Postprint (published version

How does water-reliant industry affect groundwater systems in coastal Kenya?

The industrialization process taking place in Africa has led to an overall increase in groundwater abstraction in most countries in the continent. However, the lack of hydrogeological data, as in many developing countries, makes it difficult to properly manage groundwater systems. This study presents a real case study in which a combination of different hydrogeological tools together with different sources of information allow the assessment of how increased competition for water may be affecting groundwater systems by analysing the sustainability of new abstraction regimes under different real climatic condition (before, during and after La Niña 2016). The area where this approach has been applied is Kwale County (in Coastal Kenya) in a hydrogeological context representative of an important part of the east coast of the continent, where new mining and agriculture activities co-exist with tourism and local communities. The results show that the lack of aquifer systems data can be overcome, at least partly, by integrating different sources of information. Most of the time, water-reliant users collect specific hydrogeological information that can contribute to defining the overall hydrogeological system, since their own main purpose is to exploit the aquifer with the maximum productivity. Therefore, local community water usage, together with different stakeholder's knowledge and good corporate water management act as a catalyst for providing critical data, and allows the generation of credible models for future groundwater management and resource allocation. Furthermore, complementary but simple information sources such as in situ interviews, Google Earth, Trip Advisor and easy-to use analytical methods that can be applied in the African context as in many developing countries, and enables groundwater abstraction to be estimated and the sustainability of the aquifer system to be defined, allowing potential future risks to be assessed.Peer ReviewedPostprint (published version

The Turkana Jet diurnal cycle in observations and reanalysis

The Turkana jet is an equatorial low-level jet (LLJ) in East Africa. The jet influences both flooding and droughts, and powers Africa’s largest wind farm. Much of what we know about the jet, including the characteristics of its diurnal cycle, derives from reanalysis simulations that are not constrained by radiosonde observations in the region. Here, we report the characteristics of the Turkana jet with data from a field campaign during March–April 2021: The Radiosonde Investigation for the Turkana Jet (RIFTJet). The southeasterly jet forms on average at 380 m above the surface, with mean speeds of 15.0 m s−1. The strongest low-level winds are during the night and early morning from 0300 to 0600 LT (>16 m s−1). The average wind profile retains a characteristic low-level jet structure throughout the day, with the low-level wind maximum weakening to a minimum of 10.9 m s−1 at 1500 LT. There is significant shear, of up to 1.5 m s−1 (100 m)−1 maintained through the 1000 m above the wind maximum. The diurnal cycle of the jet is associated with the nocturnal strengthening and lowering of elevated subsidence inversions, which form above the jet. Reanalysis simulations (ERA5 and MERRA-2) do not capture the daytime persistence of the jet and underestimate the speed of the jet throughout the diurnal cycle. The largest absolute errors of over 4.5 m s−1 (−35%) occur at 0900 LT. The reanalyses also fail to simulate the elevated subsidence inversions above the jet and associated dry layer in the lower troposphere

Water Security for Climate Resilience Report: A synthesis of research from the Oxford University REACH programme

This report presents a synthesis of published and ongoing research by REACH which explores the relationship between water security, climate and climate adaptation decisions, drawing on findings from REACH research conducted in Sub-Saharan Africa and South Asia. We demonstrate the unequal impact of climate on water security, and on people’s lives and livelihoods, which can be counter-intuitive to broad narratives around resilience and adaptation. We exemplify the impact of seasonal fluctuations in weather on surface and groundwater quality and quantity, and show that water security risks evolve with shifting climate conditions, water use behaviours, and policy decisions. We also present a deepened understanding of location- and context specific climate issues and dynamics, revealing a pressing need to consider and plan for different distributional impacts of climate and climate change

Groundwater hydrodynamics of an Eastern Africa coastal aquifer, including La Niña 2016–17 drought

In 2016–17 much of East Africa was affected by a severe drought which has been attributed to Indian Ocean Dipole and El Niño Southern Oscillation conditions. Extreme events such as this have immediate and knock-on effects on water availability for household, agricultural and industrial use. Groundwater resources can provide a buffer in times of drought, but may themselves be stressed by reduced recharge and increased usage, posing significant challenges to groundwater resource management. In the context of East Africa, groundwater management is also hampered by a lack of information on aquifer characteristics. With the aim of addressing this knowledge gap, this study shows the hydrogeological behaviour before and during La Niña 2016/17 drought in southern coastal Kenya on a groundwater system which sits within a geological structure which is representative of an important portion of the East African coast. Diverse hydrochemical and isotopic campaigns, as well as groundwater head variation measurements, were carried out to study the groundwater hydrodynamics and thus characterize the aquifer system under climatic conditions before and during the La Niña event. This information is complemented with an estimation of changes in local recharge since 2012 using local data sets. The main consequence of the drought was a 69% reduction of recharge compared to an average climatic year. There was reduced recharge during the first rainy season (April–June) and no recharge during the second wet season (October–December). There was a concurrent increase in seawater intrusion even during the wet season

Delivering safely-managed water to schools in Kenya

With two out of every five Kenyans aged between four and seventeen years old, education is critical for the current welfare and the future development of 20 million children attending 37,910 primary and 11,399 secondary schools. Without safe water in schools for drinking, food preparation, handwashing and general hygiene and sanitation, even basic education outcomes will prove difficult to achieve and sustain. This report presents the status of school water, sanitation and hygiene (WASH) services in Kitui County drawing upon a survey of 1,887 primary and secondary schools in 2019. We evaluate water resource risks in the county to understand how climate anomalies affect rainwater harvesting for schools and the influence of geology on groundwater quality. The report considers policy responses to guide new thinking on the delivery of safely-managed water services. The latter is informed by the performance of a professional maintenance service provider guaranteeing rapid repairs to handpumps and small piped systems within days, and monthly monitoring of water quality

How does water-reliant industry affect groundwater systems in coastal Kenya?

The industrialization process taking place in Africa has led to an overall increase in groundwater abstraction in most countries in the continent. However, the lack of hydrogeological data, as in many developing countries, makes it difficult to properly manage groundwater systems. This study presents a real case study in which a combination of different hydrogeological tools together with different sources of information allow the assessment of how increased competition for water may be affecting groundwater systems by analysing the sustainability of new abstraction regimes under different real climatic condition (before, during and after La Niña 2016). The area where this approach has been applied is Kwale County (in Coastal Kenya) in a hydrogeological context representative of an important part of the east coast of the continent, where new mining and agriculture activities co-exist with tourism and local communities. The results show that the lack of aquifer systems data can be overcome, at least partly, by integrating different sources of information. Most of the time, water-reliant users collect specific hydrogeological information that can contribute to defining the overall hydrogeological system, since their own main purpose is to exploit the aquifer with the maximum productivity. Therefore, local community water usage, together with different stakeholder's knowledge and good corporate water management act as a catalyst for providing critical data, and allows the generation of credible models for future groundwater management and resource allocation. Furthermore, complementary but simple information sources such as in situ interviews, Google Earth, Trip Advisor and easy-to use analytical methods that can be applied in the African context as in many developing countries, and enables groundwater abstraction to be estimated and the sustainability of the aquifer system to be defined, allowing potential future risks to be assessed.Peer Reviewe

Real-time indication of faecally contaminated drinking water with fluorescence spectroscopy: towards understanding the causation

Two billion people still consume drinking water contaminated with faeces. To improve this situation, it has been recognised by UNICEF and the WHO that a more rapid approach to detecting faecally contaminated drinking water is necessary. We have previously demonstrated that fluorescence spectroscopy is a significant real-time indicator of the presence/absence and number of faecal indicator bacteria in drinking waters in low-income countries of the tropics. We have also established its potential as an online indicator of faecal contamination of public water supplies in the UK. Outstanding questions remain, however, over the source of the fluorescence and its uniqueness to faecal-indicator bacteria. To address these, we sampled potable groundwater supplies in Kenya, Malawi, Senegal and Uganda across an urbanisation transect from rural Malawi through to the city of Dakar (Senegal) where pollution sources and pressures vary considerably. We report on whether the fluorescence signal in these sources is intracellular or extracellular and, in Senegal and Uganda, the ability of fluorescence spectroscopy to predict total bacteria cells and faecal-indicator bacteria