INTRODUCTION

Pakistan’s current population of 141 million is expected to grow to about 221 million by the year 2025. This increase in population will have direct impact on the water sector for meeting the domestic, industrial and agricultural needs. Pakistan has now essentially exhausted its available water resources and is on the verge of becoming a water deficit country. The per capita water availability has dropped from 5,600 m³ to 1,000 m³.  The quality of groundwater and surface-water is low and is further deteriorating because of unchecked disposal of untreated municipal and industrial wastewater and excessive use of fertilizers and insecticides. Water quality monitoring and information management is lacking, even though it’s crucial to any water quality improvement program.

Water is a source of life creation and survival of mankind on the earth. At the same time water has become a source of multiple problems to human health. Water quality is linked to the density of population, where population is dense it is susceptible to have more pollution. According to a UN study while the world population continues to surge, the availability of freshwater is on the decline and in the next two decades, many of the countries in South Asia, Middle East and Africa would face a crunch. Water contaminated with fecal bacteria, parasites and other microbes, causes about 6,000 deaths of adults and children every day. In developing countries, environmentally water quality issues were on the top followed by air pollution and solid water disposal problems. With the passage of time, water quantity is becoming scarce and the quality is deteriorating due to urbanization, industrialization, deforestation, land degradation, global warming, increasing of population, diversified domestic uses. The public health decision-makers in the developing countries are not well aware of the severity of the situation. Even if they were, the lack of good management and professionalism, together with financial constraints, contributed significantly to the water-borne health risks. It is estimated that in Pakistan around 30% and 40% of all reported diseases and deaths are attributed to poor water quality respectively. Moreover, the leading cause of deaths in infants and children up to 10 years age as well as mortality rate of 136 per 1,000 live births due to diarrhea is reported while every fifth citizen suffers from illness and disease caused by polluted water. In Karachi only, more than 10,000 people die annually of renal infection due to the polluted drinking water. The budget of majority of the poor people was often consumed by water-borne diseases owing to which they had little money left for improving their life standard (Dawn April 5, 2004).

The Pakistan Council of Research in Water Resources (PCRWR) launched “National Water Quality Monitoring Program” in the country on 17^th March 2001. The program aims at undertaking water quality monitoring in 21 major cities, six rivers and 11 storage reservoirs, canal, drains and natural lakes. Previously no consolidated effort was made to monitor quality of drinking water at the national level. As a consequence, no comprehensive data set is available on quality of drinking water. Different organizations including Pakistan Council of Research in Water Resources (PCRWR), Water and Power Development Authority (WAPDA), Environmental Protection Agency (EPA) and some individual consultants have conducted short-term studies on water quality assessment of a few cities.

PCRWR (1985) and WHO (1972-73) reported that after installation of new water supply pipes alone in 30 rural settlements of Japan, communicable intestinal diseases were reduced by 72% and that of trachoma by 64% while the death rate for infants and young children fell by 52%. Similarly in Uttarpardesh (PCRWR, 1985) after carrying out improvements in water works, sewerage, and sanitation, the cholera death rate decreased by 74%, typhoid fever death rate by 63.3%, and dysentery death rate by 23%. Additionally, 10% productive time of each person, wasted due to water-related diseases, can also be saved.

The quality of water supplies in many cities of Pakistan is deteriorating fast. The primary source of these supplies is groundwater. As a result, one hundred million cases of diarrhea are being registered for treatment in hospitals of Pakistan each year (WHO, 1972-73). A survey conducted by PCRWR (Tahir et al., 1994) showed that 81,996 cases of water related diseases were registered in Basic Health Units of Rawalpindi Division alone. According to United Nations Children’s Fund (UNICEF), 20 to 40% beds are occupied in the hospitals of Pakistan by patients suffering from water related diseases. Diseases such as cholera, typhoid, dysentery, hepatitis, giardiasis, cryptosporidiosis and guinea worm infections are about 80% (including diseases due to sanitation problem) of all diseases and are responsible for 33% of deaths (Tahir et al., 1994).

Over pumping of groundwater due to extended drought has affected the water quality adversely. According to a recent study about 70% of the 560,000 tube wells of Indus Basin are pumping sodic water. Such water can be highly injurious to soil health creating sodicity problems resulting in reduced permeability and infiltration rates in heavy textured soils. Surface-water from most of our rivers is also polluted. The Kabul River at Nowshera has high coliform content, suspended solids, high Biological Oxygen Demand (BOD) and low Dissolved Oxygen (DO). BOD values are generally above 3 and COD values range between 13 to 744 mg/l. The faecal coliform is high at 1600/100 ml to 1800/100 ml. This water is threatening to use for fish production, irrigation and domestic purposes.

In Jhelum River the DO content remains well above 7 mg/l. The BOD downstream of Jhelum is around 2.2 mg/l. River Chenab receives pollution loads from many industries and cities. As a result the DO is totally depleted in various stretches. The BOD downstream of Faisalabad is 4.2 mg/l. The pollution in River Ravi is the highest of all the rivers in Pakistan. Most waste water discharges in the river reach between Lahore and Balloki, a length of 62 km. The river presently receives 47% of the total municipal and industrial pollution load discharged into all rivers of Pakistan. The BOD in the river after receiving Lahore municipal discharges is estimated to be 77 mg/l on the basis of mean annual flow. Between Lahore and Balloki under low flow conditions, the river is completely devoid of DO and simply acts as a sullage drain.

The BOD in Indus River downstream of Attock is 2.9 mg/l. In Indus River water quality was studied at Dadu Moro Bridge at Kotri Barrage with nitrate levels at 1.1 and 7.5 mg/l, phosphate at 0.02 and 0.3 mg/l, BOD at 2.4 and 4.1 mg/l, faecal coliform at 50 and 400 per ml. Due to industrial waste discharges from Punjab and Sindh, the content of heavy metals such as nickel, lead, zinc and cadmium have also been found in Indus water. This status of water quality calls for regular monitoring for essential information and remedial measures. The national water quality monitoring program of PCRWR aims to establish permanent water quality monitoring network. The information thus generated would be provided to the planners and policy makers to devise strategies and measures to control water quality deterioration in the country.

The general objective of water quality monitoring program is to provide the information on the level of pollution in the water resources of the country. It is expected that this information would help in identifying the problem areas for initiating appropriate corrective solutions. The specific objectives of the water quality monitoring program are:

• To establish a permanent national water quality monitoring network to monitor changes in surface and groundwater quality and groundwater levels;

• To set up a national computer database on water quality for easy access by water users through Internet;

• To prepare national water quality map; and

• To suggest remedial measures for improving the water quality.

To tackle the alarming scenario of water quality concerns, previously in Pakistan only piecemeal attempts to determine and monitor the drinking water quality of a few selected areas without taking into consideration of ecological zones have been made so for, the holistic approach to monitor the chronic problem was not followed properly. After observing the gravity of the water quality problem at national level, the Pakistan Council of Research in Water Resources (PCRWR) had launched “National Water Quality Monitoring Program” in the country on March 17, 2001. The Phase-I & Phase-II of the program has been completed in 21 major cities of the country. In this report the Phase-III (summer water samples collection and analysis) water quality monitoring field as well as lab. Analytical data has been incorporated and presented covering 22 major cities of Pakistan covering Federal area and cities of all provinces viz. Islamabad, Bahawalpur, Faisalabad, Gujranwala, Gujrat, Kasur, Lahore, Multan, Rawalpindi, Sargodha, Sheikhupura, Sialkot, Mangora, Mardan, Peshawar, Khuzdar, Loralai, Quetta, Ziarat, Hyderabad, Karachi, Sukkur. Apart from these cities, six rivers: Jhelum, Chenab, Ravi, Sutlaj, Indus Hub and Kabul, five dams: Simly, Rawal, Khanpur, Hub, Tarbella, and Mangla, one reservoir: Chashma, two lakes: Manchar, and Hamal and two drains, Left Bank Outfall Drain, and Right Bank Outfall Drain have also been selected for monitoring water quality.

National Drinking Water Quality Map will be prepared on the basis of collected data and data from the previous water quality studies completed by different departments including WAPDA. It is pointed out that presently there is no agency working on national level. The information regarding water quality problems/issues all over the country are available free of cost on Water Quality Website of PCRWR for researchers, policy makers, planners and citizens for utilization in preparation of development schemes on water supply, agriculture, livestock and fisheries etc.

The PCRWR is the national research institute, which is mandated to conduct, organize, coordinate and promote research in all aspect of water resources including drinking water quality. The Council has established six research centers at Quetta, Bahawalpur, Lahore, Peshawar, Islamabad and Tandojam to address problems related with water resources. The center at Islamabad was established to address among other issues related to water quality assessment, water pollution, environmental and wastewater management activities. At present PCRWR have five well-equipped water analysis laboratories at Islamabad, Tandojam, Lahore, Bahawalpur, and Quetta while one at Peshawar is being established. PCRWR has undertaken numerous studies in the past and facilitated different organizations including educational institutes in the area of water quality research.

Under the crust of the earth, groundwater is found in a very large area, and according to estimates the amount of groundwater in the world is about 500,000 Million Acre Feet (MAF). One fifth of this source lies in the active zone, within a depth of 2,500 feet of the surface. It is more than 30 times the water contained in all fresh water lakes and is more than 3,000 times the average volume of water flowing through rivers and streams (Nazir, 1995).

Pakistan is blessed with extensive groundwater resource, which has been built due to direct recharge from natural precipitation, river flow, and the continued seepage from the conveyance system of canals, distributaries, watercourses and application losses in the irrigated lands during the last 90 years. This groundwater source has a potential of about 55 MAF, out of which about 48.69 MAF is being exploited by over 661,853 private tube wells and about 18,620 public tube wells for domestic, agricultural and industrial purposes (MINFAL, 2003). Province wise groundwater usage is 42.69 MAF in the Punjab, 3.5 MAF in Sindh, 2 MAF in NWFP, and 0.5 MAF in Balochistan. The potential of groundwater exploitation in Azad Jammu & Kashmir is only 16800 AF while existing usage is above 4300 AF. The Northern Areas, the potential for groundwater exploitation is virtually none. Groundwater use is nearing the upper limit in most parts of Pakistan. In Balochistan the watertable has been declining continuously. A number of studies have estimated that the deficit in Quetta sub-basin is about 21,000 AF per year and that the aquifer storage will be exhausted in 20 years.

For the purpose of drinking water sources, Pakistan can be divided into five major zones:

1. The sweet groundwater areas where water is easily accessible for human consumption;

2. The brackish groundwater areas where canal or river water is available;

3. The mountainous and hilly areas in the north where spring water is frequently available;

4. The eastern desert belt where groundwater may be available only at a greater depth and

5. Coastal belt of Pakistan where, generally, saline water is available. However, recent estimates of the availability and use of groundwater of an acceptable quality indicate that this resource has been heavily overexploited affecting both the quality and quantity of the groundwater (Pakistan Water Partnership, 2000).

The quality of groundwater is area specific and generally ranges from fresh with Total Dissolved Solids (TDS) less than 1000 mg/l near the major rivers to highly saline with salinity exceeding 3000 mg/l TDS.

In Punjab province about 79% of the area has fresh groundwater as defined above. Some 9.78 million acres are underlain with groundwater of less than 1000 mg/l TDS, 3 million acres with salinity ranging from 1000 to 3000 mg/l TDS and 3.26 million acres are underlain with groundwater of salinity of more than 3000 mg/l TDS. Generally, the saline water is encountered in the middle of Doabs (area between two rivers). Cholistan Desert in the Southern Punjab is well known for highly brackish waters, which cannot be used for drinking purposes. Groundwater with high fluoride content is found in the Salt Range, Kasur and Mianwali. There are also reports of high fluoride content, ranging from 65 to 12 mg/l in groundwater in Bahawalpur area. Groundwater samples taken from Jhelum, Gujrat and Sargodha districts have shown concentrations of arsenic well above the WHO guideline value of 50 mg/l. The effluent from tanning industries in Kasur has caused high TDS, chromium, sodium and sulfide contents in groundwater.

In Sindh about 28% of the area has fresh groundwater suitable for irrigation. Close to the edges for the irrigated lands fresh groundwater can be found at 20-25 m depth. Large areas in the province are underlain with groundwater of poor quality. The areas with non-potable highly brackish water include Thar, Nara and Kohistan. In Tharparker, including Umarkot, the situation is further complicated by the occurrence of high fluoride in some groundwater.

In NWFP abstraction in excess of recharge in certain areas such as Karak, Kohat, Bannu and D.I. Khan has lowered the watertable and resulted in the contamination from the underlying saline water. In Balochistan, the Makran coastal zone and several other basins contain highly brackish groundwater. In the absence of alternative sources of water local communities use groundwater with TDS as high as 3000 mg/l for drinking purposes. In Mastung Valley, groundwater has been found to have high fluoride content.

A groundwater level, whether it is the watertable of an unconfined aquifer or the piezometeric surface of a confined aquifer, indicates the elevation of atmospheric pressure of the aquifer. Any phenomenon, which produces a change in pressure on the groundwater, will cause the groundwater level to change (Tuinzaad, 1954). The change in storage, resulting from difference between supply and withdrawal of water, causes levels to change. Effects of pumping on groundwater level are important in this regard. Other localized storage changes are produced by variation of stream stage and evapotranspiration. External loads, such as tides, trains, atmospheric pressure and earthquakes are borne in part by the water of confined aquifers hence they affect piezometeric levels. Regulation of seepage through earth dams and land drainage as well as an optimistic management of the available water resources both surface and underground can control these fluctuations. The groundwater level fluctuations are mainly of two kinds.

Secular variations of groundwater levels are those extending over periods of several years. Alternatively, series of wet and dry years in which the rainfall is above or below the mean, will produce long term fluctuation of levels (Fishel, 1956). However, rainfall is not the only indicator of groundwater level changes. Recharge is the governing factor, which depends upon rainfall intensity and distribution, and amount of surface runoff. In over-developed basins where withdrawal exceeds recharge, a downward trend of groundwater level may continue for many years. Due to the continued drought for the last many years, Pakistan is facing such type of fluctuation in groundwater levels in most of the areas (Kahlown, et al., 2002).

Many groundwater levels show a seasonal pattern of fluctuations. These result from influences such as recharge from rainfall and irrigation, and discharge from pumping which follow well-defined seasonal cycles (Rorabaugh, 1956). The magnitude of the fluctuations, of course, depends upon the quantities of water recharged and discharged, and a fully developed aquifer will have a greater range than one partially developed. These kinds of fluctuations are observed in the Potowar region under the effect of monsoon season.