DRINKING WATER QUALITY STATUS AND ITS SOURCES OF CONTIMINATION
By Aryal khan panizai
Due to intimidating increase in population and rapid-fire industrialization, drinking water quality is being deteriorated day by day in Pakistan. This review sums up the issues of colorful exploration studies conducted for drinking water quality status of different areas of Pakistan by taking into account the physicochemical parcels of drinking water as well as the presence of colorful pathogenic microorganisms. About 20 of the whole population of Pakistan has access to safe drinking water.
The remaining 80 of population is forced to use unsafe drinking water due to the failure of safe and healthy drinking water sources. The primary source of impurity is sewerage( fecal) which is considerably discharged into drinking water system inventories. Secondary source of pollution is the disposal of poisonous chemicals from artificial backwaters, fungicides, and diseases from husbandry sources into the water bodies.
Anthropogenic conditioning beget waterborne conditions that constitute about 80 of all conditions and are responsible for 33 of deaths. This review highlights the drinking water quality, impurity sources, sanitation situation, and goods of unsafe drinking water on humans. There’s immediate need to take defensive measures and treatment technologies to overcome hygienic condition of drinking water inventories in different areas of Pakistan.
Water quality:
Drinking water is mainly taken from surface and underground aquifers near rivers and canals. Surface water quality is rapidly declining due to the addition of raw municipal and industrial wastewater as well as agricultural runoff to the water source. When river water flow is at its maximum, it contains a highly concentrated suspension. Most rivers are long and thin and do not support aquatic species.
It is clear that these waters are contaminated with faeces and need to be treated appropriately to remove the contaminants for human consumption. In Pakistan, four major cities use surface water; these are Islamabad, Karachi, Rawalpindi and Hyderabad.
Approximately 70% of the projected water use comes from aquifers. The decline in groundwater quality is due to the inflow of salt water and the addition of fresh water. Groundwater quality in Pakistan is salinized far from major rivers and fresh water near major rivers. The quality of domestic water is determined by the quality of the water source, the level and efficiency of treatment, and the condition of the water supply pipeline.
In Pakistan, most areas have no source of fresh water and groundwater is salty, people have no choice but to use this water for drinking. Microbial water pollution is the most pressing problem. The distribution of drinking water in urban areas does not meet WHO standards.
The main cause of microbiological contamination is the mixing of the common sewer with the domestic water supply. In most rural areas of Pakistan, surface water is used for drinking after slow sand filtration, and chlorination is not performed at filtration stations. In most rural areas, there is no pre-treatment facility for water purification. All this deficiency is due to microbial contamination and poor water quality.
Sources of Contamination:
Microbiological Contaminants;
In Pakistan, microbial pollution has been discovered as one of the serious problems in rural as well as urban areas. This is due to the leakage of pipe, pollution from sewage lines intrusion into drinking water supplies, and so forth.
Chemical Contaminants;
Chemical pollutants that come from industries, soil sediments and agricultural runoff, i.e. pesticides and fertilizers, enter water sources. In Pakistan, the use of fertilizers and pesticides is around 5.6 million tons and 70,000 tons respectively according to gross profit (GOP) figures.
These chemicals, usually insecticides, leach into groundwater by mixing with irrigation water and rainwater. Between 1988 and 2000, about 107 samples were taken from groundwater, and 31 samples showed clear pesticide contamination above the limits set by the Food and Agriculture Organization of the United Nations (FAO) and WHO. Another significant problem for groundwater in Pakistan is higher salt concentration, which is mainly caused by irrigation activities, salt dissolution in soil, seawater intrusion and chemical industries. Salinity affects major areas of Balochistan, PK and Punjab.
Wastewater from industries and households has high levels of arsenic, becoming a serious problem. In the major cities of Sindh and Punjab, about 16% of people were exposed to more than 50 ppm of arsenic. Fluoride concentrations above the permissible limit cause problems in the main regions of Balochistan, Punjab and Sindh. Dental fluorosis is common in Sindh, Punjab and KPk .
Floods Cause Major Damage to Drainage System;
In Pakistan, floods have created serious environmental problems. They damage pipes and eventually cause sewage to overflow into water bodies. Severe flooding destroyed buildings and crops. All these substances can cause toxic chemicals and oils to be discharged into rivers, streams, lakes… and can lead to the death of aquatic organisms. Many chemical pollutants enter floodwaters in their path. Current severe floods (2010) and heavy rains have damaged 80% of Nowshera, destroying 40% of infrastructure. The total number of houses destroyed and damaged
Human Health Impact;
Due to the poor sanitation system, treatment, and monitoring, drinking water quality deteriorates. The presence of toxic chemicals and bacteria in drinking water causes adverse effect on human health. Due to the fecal contamination, people have been suffering from waterborne diseases. In rural and urban areas of Pakistan, cases of waterborne diseases, typhoid, dysentery, cholera, and hepatitis are systematically reported. However, it is very difficult to properly quantify the danger due to several reasons.
They include underreporting of diseases and poor record maintenance in healthcare centers and hospitals related to diseases caused by poor water quality
Management Strategies;
Management strategies should cover protection of sources from contamination, drinking water distribution lines upgradation and their proper maintenance, and monitoring and awareness of the people.
The author, Aryal khan, is a student of Environmental Sciences department at University of Balochistan.
