Safe water for every life
Our environment is made up of everything visible and invisible in front of us. Every element of the environment is driven by precise natural laws and regulations. Water is one of the most important natural elements in our planet. It plays an important role in maintaining the balance of the environment because three-fourths of our planet is water. Huge bodies of water cover about 61% of the earth's surface. Even though we have huge reservoirs of water, we cannot use most of the water because about 98% of our total water is saline or seawater which we cannot use directly. The amount of water we use is very limited which is about 3% only. Of this, 0.01% is stored in the atmosphere, 1.625% in glaciers, 0.0012% in soil, 0.141% in land and 0.4-1.6% in groundwater.
Analysis of water reveals one atom of oxygen and two atoms of hydrogen. What we mean by pure water or safe water is clear, colourless, odorless and tasteless water. Pure or safe water contains various beneficial elements like calcium, magnesium, iron etc. We can drink safe water directly from the groundwater. Except ground reserved water, water from all other sources has to be processed. Rain water is also called safe water but rain water also cannot be drunk directly.
We usually get water from three sources - rainwater, surface water and groundwater. At one time we used to get safe drinking water from these three sources. Over time, all sources have become polluted and many have become wasteful garbage. The total water body of Bangladesh is 11 percent of the total area of the country.
Our country is the land of thirteen hundred rivers including Padma, Meghna, Jamuna, Brahmaputra, Karnafuli. But as a result of rapid urbanization, factories, industrial plants, housing, etc. have been built by filling the rivers as well as other water bodies. As a result, safe sources of water are facing destruction today.
Whether water is safe to drink and use or contaminated can be ascertained through various physical, chemical and biological indicators. Temperature, clarity-opacity or turbidity and visual tests are important as physical indicators. It measures how clear the water is and whether it is usable or not. Chemical indicators are very important and include pH, taste, odor, COD or amount of dissolved oxygen or DO.
Water can be contaminated from various identified or point and unmarked or non point sources. Any unwanted and unhealthy substance in the environment mixes with water and pollutes the water by altering the physical, chemical and biological properties of the water. Some of the notable sources of water pollution are industrial waste, household waste, agricultural pesticides, various radioactive substances, hot water from power plants, silt, arsenic pollution, septic tanks, oil spillage, waste dumping etc.
Ammonium chloride, cyanide, zinc, mercury, lead are found in large quantities in petrochemical industry, polythene and plastic industry, fuel, mineral oil refining, small and medium electrical industry and vehicle manufacturing industry which can contaminate usable water by mixing with water very quickly.
Various pesticides and chemical fertilizers are used in agriculture including DDT, Aldrin, Fungicides, Insecticides, Paris Green and Lead Arsenate. These agricultural wastes mix with the rain water and fall into the nearby rivers or water bodies and cause water pollution. Many times oil from oil tankers accidentally falls into the water and contaminates the water and creates a thin film over the water body. In addition, mixing mineral oil from sea ports can also waste water.
The radioactive materials used in nuclear reactors and scientific laboratories are dumped in the surrounding ponds which eventually merge into the sea water. The warm water emitted from the power plant also contributes to water pollution. This water is low in oxygen which is an obstacle to the survival of aquatic animals. In addition, uncontrolled extraction of water from the soil layer results in arsenic reacting with air to form volatile metal compounds, contaminating the water, and prolonged exposure can lead to a disease named arsenicosis.
Contaminated and waste water from factories is mixing with the water of the reservoir and is having a huge impact on the ecosystem there. Fish living in the water of the pond are dying. Plankton-like organisms phytoplankton and zooplankton are being born in excess and in some places the amount of algae is increasing and losing balance.
Increasing in phosphorus and nitrogen are also occurring, such as eutrophication. Toxic substances like various heavy metals like lead, mercury are entering the human body unintentionally which is not desirable at all. This toxic water mixes with the sea through the river and affects the sea creatures. It is also blamed for incidents like coral bleaching. As a result of cultivation by contaminated water, contaminant enters the food chain and becomes a threat to every level.
Water is being uncontrollably polluted due to rapid urbanization, industrialization and many other reasons. As responsible citizens, it is our responsibility and duty to conserve water. In order to prevent water pollution, the Water Prevention and Pollution Act 1974-1998 and 1981-1999 have been enacted.
The extraction of water from the groundwater should be reduced. We can use aerators in our every water tap so that the water wastes can be reduced as aerators help to save water by adding air on the water flow. Rain water should be stored and used. Many developed and coastal countries are artificially extracting natural rainwater through cloud seeding. Different kinds of salts are used in it. This method is extremely expensive for developing countries like ours. So we need to save naturally harvested rainwater.
Unplanned use of water from water sources will lead to extreme water crisis in the world. According to environmentalists and geologists, water will be the cause of the next world war.
Extreme water shortages have already occurred in many parts of Africa, resulting in no crop production in those areas. So famine has occurred in all those areas. Sinkhole like natural hazards are emerging in many areas of the world.
Under the pressure of urbanization, industrialization and growing population, our nature and environment have been and are being severely damaged. Everyone must abide by the law made. Only then will it be possible to preserve nature, its elements and the existence of mankind.
The writer is a student, Department
of Environmental Science and Engineering, Jatiya Kabi Kazi Nazrul Islam University, Mymensingh