DOMESTIC WATER SUPPLY FOR ISLAMABAD: FUTURE CHALLENGES

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1 DOMESTIC WATER SUPPLY FOR ISLAMABAD: FUTURE CHALLENGES by Dr. Shahid Ahmad Resource Picture Domestic water supply for inhabitants of Islamabad depends on both surface and groundwater resources. The designed capacity of the available resources is around 107 million gallons per day (mg/d). The major source of surface water for Islamabad is Simly dam. Groundwater is obtained from tubewells installed in the National Park area. Spring water is diverted from springs located at Saidpur, Nurpur and Shahdra-hills. Continued drought conditions prevailing in the country as a result of La' Nino has resulted in to reduced inflow to the Simly dam and thus recharge to the groundwater is reduced. The reduced inflow to the Simly dam has also resulted in to over-exploitation of groundwater to meet shortfall in water availability from surface water resources. Number of wells in the twin cities of Islamabad/Rawalpindi has also been lowered due to decline in the water table. Thus, in general, the water table is lowering in both the cities. This decline in the water table is not only due to the drought conditions but also because of the continuously increasing demand. Thus the residents of Islamabad are installing small tubewells to meet shortage of water supply. Reduced inflow of water to the Simly dam has reduced the withdrawal of water for the supply to the residents of Islamabad. At present, approximately 64 mg/d of water is being produced against the demand of around 81 mg/d. Due to the shortfall in water availability, rationing in water supply is being practised in almost every sector except F-6 and G-6 due to non-availability of storage tanks at the household level. This is true to some extent because the government employees occupy most of the houses in these sectors.

2 Live storage capacity of the Simly dam is continuously declining due to sedimentation in the reservoir. The groundwater resource is also declining due to decline in water table. However, the demand for water supply would increase in future. Thus the CDA will be facing acute problem of resource shortage in future. The other important physical limitation is that the resource is not fixed rather variable in dry and wet years. The inflows to the Simly reservoir in a dry year are almost half of the wet year. Thus the problem would be more complex in dry years until new resources of water are developed and maintained. Treatment of Water There are two common methods of emergency dis-infection -- boiling and chemical treatment. Boiling of water for 6-15 minutes can take care some of the biological contamination. For chemical treatment chemicals like chlorine or iodine are used. In the process of chlorination, the chemicals normally used are: a) chlorine; b) chlorine bleach; c) granular calcium hypochlorite; and d) chlorine tablets. Tincture of iodine and iodine tablets are also used for chemical treatment. CDA uses the conventional methods of coagulation, flocculation, sedimentation, filtration and dis-infection for the preparation of potable water. For the oxidation and dis-infection purposes liquefied chlorine is used. For the operation and maintenance control of a water-supply system critical parameter testing strategy has been preferred over less frequent lengthy testing techniques. Water borne diseases are normally emanating from the pathogens as well as from the inorganic contaminating potable water. Several experts have recommended that sanitary inspection should take preference over analysis for the assessment of risk to human health due to contamination. Some of the precautionary measures are to: a) identify sources of pollution; b) document distances to sources of pollution; c) identify type of pollution; d) provide sanitary protection of springs and wells; and e) dis-infection of springs.

3 Quality of Water Turbidity, colour, taste and odour, and temperature are the essential elements to describe the physical characteristics of water quality. Chemical characteristics also describe the water quality. The toxic substances include arsenic, barium, cadmium and chromium. Chlorination is used by CDA for chemical treatment of water. Thus chlorine concentration is an important indicator of domestic water quality in Islamabad. Copper, fluoride, iron, manganese, nitrates, sodium, sulfates, zinc, and lead are other elements t describe chemical characteristics of potable water. Biological factors include contamination of water supplies based on organisms, which cause human diseases, and originate from faecal discharges of infected individuals. Precautions are required against contamination or treatment methods are used to overcome this problem. It is difficult to identify the disease-producing organisms in water because techniques used for bacteriological examination are complex and time-consuming. Number of bacteria of Coliform group describes the bacteriological quality of water i.e. one organism for each 100 millilitres of water. Fertiliser materials such as organic and commercial minerals also pollute water due to indiscriminate use in agriculture. Treatment is essential for the destruction of biological life or its by-product in water. Strategy and Framework for Action Managing Quality of Inflow to Simly Dam Quality of inflow to the Simly dam has to be managed more effectively due to the increase in human activities in the future. The human population in the catchment areas is increasing at a faster rate and tourism is also increasing in the area. Thus increase in residential population and business would also result into the increase in poultry farms, hotels, hospitals, etc. Therefore, these changes would result into increased effluents of human and animal wastes, hospital wastes, wastes of petrol station and workshops and other pollutants. The increase in productivity and intensive farming in the catchment area further requires more dependence on chemical fertilisers and pesticides. In fact, the trend of intensive agriculture in the catchment area has to be reversed

4 towards more plantations of forest plants and shrubs. Rather interventions of eco-tourism have to be introduced to provide alternate sources of income to the inhabitants of the catchment area. Traditional concept of plantation and check dams in the catchment area has to be changed to a more comprehensive strategy of watershed management covering all activities of human in the catchment area. For this purpose, entry point must be motivation or catchment communities and introduction of alternate and environment friendly interventions for income generation. Gauging stations have to be established for major tributaries and at main points to monitor flow of sediments, and quantity and quality of the inflow. This will help to develop strategies for managing the quality of inflow to the Simly dam. Maintaining Quality of Spring and Groundwater Most sustainable methods of maintaining quality of spring and groundwater are to completely block the entry of pollutants to domestic water supply. The pollutants include effluent of sanitary system, industrial effluent, hospital waste, municipal waste, etc. First step would be the treatment of sanitary effluent prior to its entry to the waterways. At least one model system has to be developed using oxidation methods and microorganisms. The effective microorganisms helped to reduce the demand for oxidation. Furthermore, the approach should be to provide relatively safe water for growing of plants, shrubs and vegetables. Management of sanitary effluents must be linked with utilisation of treated water to reduce the treatment cost. In fact, the O&M cost of the traditional treatment systems is so high that these systems are hardly operated in Pakistan. Therefore, there is a genuine need to develop costeffective water treatment systems, which have very little O&M cost. Managing Pipeline Network Recent study conducted by NESPAK indicated that there is around 33% loss of water in the domestic water supply system. The major loss is associated due to leaky pipelines, breakage and faulty control systems (valves, etc.) and other losses. These losses may increase in future and thus efforts are needed for developing operational management plans for supply of water to the

5 residents of Islamabad. The saving in existing losses would also reduce the need for developing new water resources in the future. Leaky water supply systems are also subjected to contamination especially from the sanitary effluents. Recent operational management systems developed in the western countries have to be acquired and adapted for local conditions. There are higher chances of having droughts in future due to climate change and global warming; therefore, operational management of the pipe network has to be improved. New domestic water supply systems have to be developed differently by changing the type of piping from MS/GI to polyethylene with black carbon and UV stabilisers, which are safe for drinking water and have longer-life. At least, these pipes must be tried on a pilot-scale. The cost of these pipes is almost half of the GI pipes. These pipes can also be used for buildings. However, for on on-surface installations, GI pipes have to be used to avoid vandalism. Therefore, underground GI pipes can be replaced with PE pipes. The PE pipes are now produced in the country and WRRI- NARC is the pioneering institution for initiating manufacturing of these pipes in the country in collaboration with the local industry. These pipes are equally suitable for mountainous regions, where GI pipes can not resist problem of freezing and thawing. Most essential element of managing any pipeline system is to introduce the concept of water measurement. Water measurement is a better water management for domestic water supply. Such measurements can help Water Managers for effective management of the system. Actually a culture of measurement has to be introduced in CDA. In my opinion, capacities of the Water Managers have to be upgraded for improved management of the domestic water supply systems. In summary, management of water supply network would require three major activities: a) saving of existing losses in the pipe network; b) sanitary protection; and c) metering of water. Resource Development Watershed management in the catchment area should be initiated on comprehensive basis to enhance recharge to the groundwater. In addition to this, there is an urgent need for enhancing

6 existing storage of Simly dam by raising the dam. Construction of additional storage reservoirs is also needed to increase availability of surface water for Islamabad. Furthermore, management of existing small ponds and reservoirs including the MIRAD Project dams should be given high priority. For this purpose CDA has to develop effective linkages with the ICT Administration. Thus urban and rural Administration of Islamabad have to work together. Utilisation of Water Consumers in utilisation of water should introduce conservation practices. Reuse of grey water may be considered for lawns and car washing. Specialised water piping systems may be designed for reuse of water at the household level especially for the newly constructed residential buildings. In addition to this the consumers institutions and forums must arrange awareness campaigns to motivate the consumers for conservation of water through efficient and effective utilisation. In conclusion, there is a need to have partnership between various stakeholders -- residents of Islamabad, Consumers Forums, Advocacy Groups and the CDA. Such a partnership would help to initiate systematic effort for managing and conserving the resource, maintaining quality of domestic water supply and effective utilisation of the scarce resource. Rather CDA may take it as a challenge to develop a model system of water supply for Islamabad, which can be followed by other municipalities and metropolitans in the country. The future challenges can't be addressed without effective partnership between various stakeholders. CONCLUDED * Chief Scientific Officer/Director, Water Resources Research Institute, National Agricultural Research Centre, Chak Shahzad, Islamabad. Phone: ; Fax: