World Water Day: water for cities Preksha Bhardwaj Vivekananda Institute of Technology Electronics and Communications II semester
World Water Day is observed on March 22 since 1993 when the United Nations General Assembly declared March 22 as World Day for Water. The UN and its member nations devote this day to implement UN recommendations. In addition to the UN member states, a number of NGOs are promoting clean water and sustainable aquatic habitats.
Why world water day? The UN hopes that the Decade will boost the chances of achieving international water-related goals . For the rapidly urbanizing developing world, safe and affordable water is key to health and livelihoods, as well as meeting the Millennium Development Goals. This is an unique occasion to bring all the stakeholders together to apply solutions to that work.
WATER FOR CITIES Water use has been growing at more than twice the rate of the population increase. It is estimated that : 22% of worldwide water use is industrial. 69% of worldwide water use is for irrigation. 8% of world wide water use is for household purposes. Management of water resources has become an urgent issue as urban and peri-urban farmers often apply water from municipal sewage, mostly in its untreated form, increasing the risk for illnesses to farmers and consumers.
Water Scarcity in citiesCauses : Population growth and urbanization Industrialization Climate changes Conflicts and natural disasters Growing urban water and sanitation demands Pollution from municipal and industrial discharges Over exploitation of available resources
If you don’t treat water as dear itwould become dreadrer
Population growth and urbanization Today, the developed regions have the highest percentage of urban population. But the 2015 projection shows a reversing trend, with half the population of the less developed regions living in urban areas. According to the Population Division of the United Nations, by 2025 it is foreseen that 75% of the world’s urban population will live in the less developed countries. In 2020, the urban population in developing countries is expected to reach 50%.
Main water issues related to urban growth The major consequence of the urban influx is the growing demand for water and sanitation services. The gap is continuously widening between the demand for and the supply of these services.Over exploitation Because of the growing demand, urban authorities have been led to over exploit valuable sources, leading to water crises . For example Mexico city depends on ground water from the Mexico Valley aquifer for 80% of its water supply . The depletion of the aquifer has caused a shifting of the land and the city is now sinking.Pollution The lack of wastewater treatment and drainage facilities, due to the poor maintenance or the lack of sanitation infrastructure , leads to pollution of the ground-and surface water resources. The problem is mainly in coastal areas. The pollution of rivers and seas is at the top of the list of environmental problems affecting coastal cities. For example the city of Lima in Peru discharges 18000 L of waste water /sec into pacific ocean.
Health Lack of convenient sanitation implies the lack of safe water supply. When it rains heavily, storm water washes accumulated human waste, mainly from informal settlements lacking minimum facilities, into open boreholes and other water sources used by the poor for drinking water. This results in cholera epidemics, like that erupted in east Africa in 1997- 98 . Faecal-oral diseases, mainly diarrhea , are one of the greatest risks posed by the lack of adequate water supply and sanitation. Children are the first, and the hardest, hit: child mortality rates in cities with proper sanitation and water supply are generally around 10 per 1,000 live births. Diarrheal diseases are still a primary cause of child mortality in the world’s urban populations.
Climate changes Water scarcity is expected to become an ever-increasing problem in the future, for various reasons. First, the distribution of precipitation in space and time is very uneven, leading to tremendous temporal variability in water resources worldwide . Second, the rate of evaporation varies a great deal, depending on temperature and relative humidity, which impacts the amount of water available to replenish groundwater supplies.The hydrological cycleKey changes to the hydrological cycle (associated with an increased concentration of greenhouse gases in the atmosphere and the resulting changes in climate) include: Changes in the seasonal distribution and amount of precipitation. An increase in precipitation intensity under most situations. Changes in the balance between snow and rain. Increased evapotranspiration and a reduction in soil moisture. Changes in vegetation cover resulting from changes in temperature and precipitation. Consequent changes in management of land resources. Accelerated melting glacial ice. Increases in fire risk in many areas. Increased coastal inundation and wetland loss from sea level rise. Effects of CO2 on plant physiology, leading to reduced transpiration and increased water use efficiency.
Changes in precipitation and Drought Patterns Projections of changes in total annual precipitation indicate that increases are likely in the tropics and at high latitudes, while decreases are likely in the sub-tropics, especially along its pole ward edge. Thus, latitudinal variation is likely to affect the distribution of water resources. With the population of the sub-tropical regions increasing, water resources are likely to become more stressed in these areas, especially as climate change intensifies. More precipitation will increase a regions susceptibility to a variety of factors, including Flooding - a region that experiences higher annual precipitation and more runoff increases the likelihood for flooding. Rate of soil erosion Mass movement of land Soil moisture availability - warming accelerates the rate of surface drying, leaving less water moving in near-surface layers of soil. Less soil moisture leads to reduced downward movement of water and so less replenishment of groundwater supplies.
Melting glacial ice• Water supplies can also be affected by warmer winter temperatures that cause a decrease in the volume of snowpack. The result is diminished water resources during the summer months.• Consequently, these areas will become increasingly susceptible to water shortages with time, because increased temperatures will initially result in a rapid rise in glacial melt water during the summer months, followed by a decrease in melt as the size of glaciers continue to shrink.• This reduction in glacial runoff water is projected to affect approximately one-sixth of the worlds population .
Conflicts and natural disastersNatural disasters too affect the water quality and quantity as we discussed in above reasons: Drought Melting of glaciers Floods
Growing urban water and sanitation demands When climate change causes water scarcity, the people who are affected often move to new areas in search of new supplies. When this happens, a water supply that has been used by a smaller group of people must now support a larger group of people. Eventually, a new water scarcity problem is created and may induce further migration. Hence a growing demand for urban water and sanitation creating water scarcity.
Target 10 under the Millennium Development Goals (MDG) is to halve by 2015 the proportion of people without sustainable access to safe drinking water and basic sanitation. The International Development Association (IDA), has been working to improve access to water and sanitation in the world’s poorest countries and has seen real progress over the last 15 years. In Ghana, the Second Community Water and Sanitation Program (2000-2004) adopted a community-driven approach to water supply, supporting Ghana’s decentralization strategy through grants.
The Small Towns Water and Sanitation Project in Uganda (1995-2003) succeeded in improving water supply services for over 190,000 people in 11 towns and significantly reduced time spent on water collection. The Yemen Social Fund for Development (1997-2003) provided basic social and economic services to almost 10 million people, of which almost 2 million benefited from access to water supply services. A follow up project (2001- 2006) provided more than 820,000 people with improved environmental sanitation—for example, working gutters, and efficient rubbish removal. In rural areas of Indonesia, 600,000 households and 3,000 schools have benefited from improved water supply and sanitation services under the Second Water and Sanitation for Low Income Communities Project (2000- 2010).
National plans by government India is endowed with a rich and vast diversity of natural resources, water being one of them. Its development and management plays a vital role in agriculture production. Integrated water management is vital for poverty reduction, environmental sustenance and sustainable economic development. National Water Policy (2002) envisages that the water resources of the country should be developed and managed in an integrated manner. Non-conventional methods for utilization of water such as through inter- basin transfers, artificial recharge of ground water and desalination of brackish or sea water as well as traditional water conservation practices like rainwater harvesting, including roof-top rainwater harvesting, need to be practiced to further increase the utilizable water resources. Promotion of frontier research and development, in a focused manner, for these techniques is necessary.
At household level we can just try to save water and not wasting it.“SAVE IT BEFORE YOU NEED IT”Some useful tips for saving water: Disposing waste in bins rather than in water bodies. Keep a check on leakages. Adjust sprinklers so that only your lawn is watered. Wash fruits and vegetables in pan of water . Use broom instead of hose to clean your driveway. When cleaning your fish tank give the nutrient rich water to your plants. Collect water from your roof to water your plants.The list is endless . You can save 1000 gallons of water everyday just by following small -small tips. but
The important one is : RE-duce , RE- use , RE-cycle water is life
Harvest rain water Don’t waste water .Try to save itEliminate bottled water Stop the trickle
As an individual I am really zealed to do my bit :“Tap the tap” while brushing and washing. Don’t let the washed water drain . Four minute shower ,and not a quarter hour. By encouraging youth through posters , plays , etc.