- Risk of climate change in Asia
- Climate change and WASH
- Possible areas of discussion
- Health impacts of climate change linked to water and sanitation changes
There is a sufficient evidence about the changes in climate and weather patterns across all the countries. The change in temperature, precipitation and rising sea level have implication on our environment, human being and infrastructure. Climate change and its associated consequences have implications on human health and prosperity. Climate variability threatens very lives and exacerbates existing development challenges such as rapid urbanization, poverty, inequality and agriculture thus having consequences on food security and nutrition. But it also exacerbates vulnerabilities in terms of infrastructure can cope with shocks.
People all around the world are witnessing climate variability. Between 1996 and 2015, more than 528 000 people died worldwide and losses of US$ 3.08 trillion (in PPP) were incurred as a direct result of almost 11 000 extreme weather events . Precipitation, floods, droughts and landslides were the major causes of damage. The extreme weather events associated to climate change are already perceptible in South Asia. Changed monsoon patterns, fluctuation in rainfall affecting river flows, droughts, floods and sea intrusion are causing severe damages to the infrastructure and economies especially to agriculture and giving rise to new problem such as urban flooding in South Asia. The disasters have serious consequences for sanitation infrastructure and worsen overall hygienic conditions as sewer in urban areas and faecal materials in rural areas mix with flood water to pose serious health threats.
As more regions of the world are being affected by extreme events related to climate change, such as storms, floods, droughts, high temperatures and humidity, and sea level rise, it is being realized that these areas often overlap with areas of high poverty and low access to essential services, such as water and sanitation. In fact, it is being realized that climate change could make existing inequities worse, through a vicious cycle of deprivation associated with slow recovery from previous disasters and greater vulnerability to subsequent climate change induced extreme events.
Climate change is mainly a change in water cycle- droughts, floods, cyclones and rising sea levels are all a material threat to the sustainability of WASH infrastructure and services, posing serious challenge for the authorities to cope with it through an effective adaptation mechanism in addition to reaching out millions who are unserved in South Asia.
Climate variability and weather extremes, such as droughts, floods and cyclones, already pose considerable risks to the delivery of sustainable water and sanitation services. Such extreme weather events have a wider and more acute impact in the absence of robust water and sanitation services.
Climate change is increasing these risks, as well as introducing new water-related challenges as sea levels rise, glaciers melt, and vector and water-borne diseases spread .
Drought leads to insufficient water resources being available to flush sewage systems adequately, and accompanying higher temperatures can have an impact on how sewage systems operate. Flooding, from storms or sea level rises, can lead to inundation of both pit latrines and sewage treatment facilities, which increases the risk of contamination of the environment. Storm water drainage is combined with the sewerage system in many existing urban systems. This puts urban areas at risk from sewage contaminated flooding. Sewage treatment plants are often positioned on low-lying ground, as sewerage systems rely on gravity, but this puts them at risk of failure as groundwater levels rise due to flooding or sea-level rise. Rivers and other bodies of water are regularly polluted with untreated sewage.
Low agriculture productivity will affect food and nutrition causing fight against diarrhea more difficult. But also, reduced rural income decrease investment in sanitation which may further affect the rural sanitation progress which is already lagging behind. Most of the rural sanitation investment comes from households themselves, therefore the fall in income may affect overall sanitation investment and progress.
It is generally the poorest people, living on low-lying ground susceptible to flooding, and with the least ability to protect themselves from extreme events, who are worst affected by the impact of climate change, further entrenching existing inequalities.
The 5th report of working group 2 of inter-governmental panel on climate change released in 2014 includes a significant discussion on the impact of climate change on fresh water resources. The changes expected include :
- Climate change is projected to reduce renewable surface water and groundwater resources significantly in most dry subtropical regions. This will intensify competition for water among agriculture, ecosystems, settlements, industry, and energy production.
- Climate change is likely to increase the frequency of meteorological droughts (less rainfall) and agricultural drought
- Climate change is projected to reduce raw water quality, posing risks to drinking water quality even with conventional treatment
- Higher ambient temperatures which increase the evaporation rate. These changes decrease natural storage of water, and hence, unless precipitation increases, its availability. Moreover, higher ambient temperatures increase water demand
- Shifts in timing of river flows and possible more frequent or intense droughts, which increase the need for artificial water storage.
- Possibly drier conditions, which increase pollutant concentrations. This is a concern especially for groundwater sources that are already of low quality, even when pollution is natural as in India and Bangladesh, North and Latin America and Africa; here arsenic, iron, manganese, and fluorides are often a problem.
- Sea level rise, which increases the salinity of coastal aquifers, where groundwater recharge is also expected to decrease.
- Wet weather: heavier rainstorms mean increased amounts of water and wastewater in combined systems for short periods. Current designs, based on critical “design storms” defined through analysis of historical precipitation data, therefore need to be modified. New strategies to adapt to and mitigate urban floods need to be developed, considering not only climate change but also urban design, land use, the “heat island effect,” and topography
- Dry weather: soil shrinks as it dries, causing water mains and sewers to crack and making them vulnerable to infiltration and exfiltration of water and wastewater. The combined effects of higher temperatures, increased pollutant concentrations, longer retention times, and sedimentation of solids may lead to increasing corrosion of sewers, shorter asset lifetimes, more drinking water pollution, and higher maintenance costs.
- Sea level rise: intrusion of brackish or salty water into sewers necessitates processes that can handle saltier wastewater.
II. What is the current level of knowledge and awareness among public, but mainly among the relevant government agencies who are responsible for dealing with the challenges of climate change?
III. What is the level of current research, data and knowledge generation on the implications of climate change on sanitation and resultantly human health? What changes are being observed, is there any systematic data gathering, analysis and knowledge generation and dissemination mechanism in place? How that system is designed and working?
IV. What is the level of institutional preparedness to deal with challenges related to climate change? How is information flowing and decision are made? What is current level of capacity and skills of the key officials to initiate, implement and manage new techniques and systems designed to cope with changes?
V. Is there adequate financial resources available to try and test new climate adaptive systems and techniques? How these additional resources have been mobilized and spent? What is the cost of developing and sustaining climate resistance sanitation systems and practices both in rural and urban areas?
VI. Climate change will affect many sectors and institutions, is there any inter-agency linkage and collaboration to share knowledge, best practices and working together? How that inter-agency collaboration has evolved, working and strengthened?