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POLLUTION SURVEY

Table of Contents

• Summary
• Introduction
• Sampling
• Physicochemical Study
• Bacteriological Study
• Conclusion
• Recommendations
• Bibliography

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SUMMARY

Results obtained for the pollution survey revealed that the temperature, pH, alkalinity and hardness of water, what so ever its location and source may be are within the normal range of potability. Conductivity, which is actually the measure of mineral contents, remained under the permissible level everywhere. Total solid content of the main river proved within the normal range of potability whereas, in tributaries its content was generally high, i.e. coming under the maximum limits of potability.

Total suspended solids generally crossed the normal range of potability i.e., 30 mg/ml. Its maximum quantity (1000 mg/l) was recorded in the sample collected from Daral Khwar, which might be as a result of the accelerated erosion of rock material due to the high water speed. The total dissolved solids were maximum in Barwai Khwar i.e. 480 mg/l, which comes under the normal limits of drinking water.

Dissolved Oxygen, which determine the health and self purifying capacity of water body was lowest in Jambil Khwar, i.e. 5.9 mg/l still high than the minimum required limits (5mg/l) of WHO. Biological oxygen demand remained under the normal limits (7.5 mg/l) down stream upto Mingora, but at once reaches to 11.6 mg/l at Punjigram after receiving the polluted water of Jambil Khawr. This situation gradually improved downstream at Gammon Pul and Pul Chwakai where the quantity of BOD recorded was 9.6 and 5.86 mg/l respectively. The valve of Chemical Oxygen Demand (COD) in Swat River and its tributaries was high than the normal acceptable limits. The concentration of ammonia fall under the acceptable range for Swat River downstream till Mingora, but the addition of effluents from Mingora municipality, it crosses the acceptable limit of 2.00 mg/l. The nitrite content in all the samples except that collected from Jambil Khwar (12.09 mg/l) proved within the normal range of potability. Whereas the concentration of nitrates in all the water bodies were within the acceptable limits of water quality. Concentration of chlorides and phosphates proved lower, whereas the sulphide contents in all the samples were higher than the WHO standards. Furthermore, the concentration of sulfates was higher than the potable limits except in the water collected from Jambil Khwar. Here it was 330 mg/l, showing the large-scale addition of domestic waste into the water body.

Among metals the concentration of sodium, copper and potassium were generally within the acceptable limits of potability in all the waters. The concentration of

potassium in the water of Jambil Khwar and that of cadmium and lead generally exceeded the normal range of potability.

The Escherichia coli counts was proved to be at the level of intermediate risk value at up and down stream Kalam. While rest of the sampling areas of Swat River and its tributaries were at high risk of fecal contamination. Whereas the water of Jambil Khwar proved to be at the very high-risk level.

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INTRODUCTION

1. Produce comprehensive baseline data, for the peak tourist season, regarding the quality of water of Swat River and its selected tributaries.
2. Compare the quality of the water of Swat River at different locations, and its tributaries.
3. Provide a stand point for future monitoring, rehabilitation and conservation programs of the Swat River.

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SAMPLING

For recording the pollution level of Swat River it was sampled upstream and down stream of the major settlements from June 25 to July 5, 1999. From each spot water was collected in sterilized bottles, four feet from the river bank and two feet deep from the surface separately for the physicochmical and bacteriological analysis. Simultaneously the temperature of water was rated at the sampling spot. Sampling was also carried out from selected tributaries. Sample sites are given in table 1.

LOCATIONS SELECTED FOR SAMPLE COLLECTION

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PHYSICOCHEMICAL STUDY

Pollutants may be physical, chemical or biological in nature. Each of them can further be classified in a variety of ways, causing variety of health problems ranging from acute physical disturbance to virulent epidemics in certain cases. Here the physicochemical pollutants are treated separately.

PHYSICAL CHARACTERIZATION OF WATER FROM SWAT RIVER AND ITS TRIBUTARIES

1.    Color, Odor and Turbidity

When the water samples were observed all the samples except No. 9 (table 1) were clear and odorless.

2.     pH of the Water

Broadly speaking pH is the measure of the acidity or alkalinity of water. The role of pH in water chemistry is associated with corrosivity, alkalinity, hardness, carbon dioxide stability and solubility and stability of metal ions.

There is no immediate direct effect of pH on human health e.g. pH of soft drinks is. between 2.0 - 4.0 and the same can be said for foods e.g. apple has a pH 2.9 - 3.3 on the acid side of the pH scale (De Zuana, 1992).

The pH of natural water is seven, however, it is generally greater than seven because of the sufficient quantities of carbonates. Variation in pH of the same water body can even be expected during day and night e.g., at day time the amount of carbonates is decreased due to photosynthetic activities in which the carbon dioxide is utilized while at night it is increased.

According to WHO the optimum, range of pH for aquatic life is 6.8 - 9 while the recommended values for pH of drinking water is 6.5 - 8.5. While the same limits have been recommended by the USEPA and European community. Although it is recognized that some problems could arise if the pH level is below 7 (WHO, 84).

The pH of all the sample collected from Swat river and its tributaries (Table 2, Figure 2) fall within normal range of potability i.e. 7.0 - 8.2, which shows that all the water studied are fit for aquatic life.

3.    Temperature

Temperature values of water is generally not considered in the public health criteria, because of its insignificant health effect. The U.S. Public Health, U.S. EPA and the WHO have not issued any guide limits for water temperature.

The temperature has pronounced effect on the treatment, aquatic life, chemical and bacteriological reaction taking place in the water. For every 10^o rise in temperature the rate of biochemical reaction doubles. In fresh water dissolved oxygen reaches 14.6 mg/L at 0^oc and approximately 9.1, 8.3 and 7mg/L respectively at 20^oc, 25^oC and 35^oC. (De Zuana, 1992). The temperature of the Swat River is from 10 - 14^oC within the area studied and the temperature of its tributaries is 11, 17, 19 and 20^oC for Daral and Chail Khwar, Barwai, Arunai and Jambil Khwar respectively. (Table 2, Figure 3)

4.     Conductivity

Conductivity is a useful test for quick determination of minerals in water. It is the measure of electric current in the water carried by the ionized substances.

The dissolved (suspended) solids are basically related to the measures that are influenced by the good conductivity of inorganic acid, bases and salts and, poor conductivity of organic compounds or total solid.

The permissible level recommended by WHO is 2000 µS cm-1 (WHO, 1984). Results for electrical conductivity shows (table 2, Figure 4) that the conductance of all the samples are within permissible level of WHO.

5.     Total Solid

It is the aggregate amount of all the floating, suspended settable and dissolved forms of solids present in water taken for analysis.

Solid’s represent the most frequent pollutants of surface water. Soil erosion gives rise to total solids in water. Total solid in all samples ranges from 200-1000 mg/L (Table 2, Figure 5). In river samples the TS value is 400, 200, 400, 580, 300, 600 and 200 mg/L for upstream Kalam, downstream Kalam, downstream Madyan, downstream Khwazakhela, downstream Mingora, Barikot and Chakdara samples respectively.

The comparatively high frequency of total solids in upstream Kalam is due to the high speed of Gabral River. Whereas in downstream Kalam the lower concentration of TS is due to the mixing of Ushu Gol and in which the sediments is generally settled in the ponds formed by the river in Mahodand.

However it is clear from the results that generally with the increased water speed erosion speeds up and the amount of total solids is increased.

In tributaries the Daral Khwar had a maximum level of TS (1000mg/L) which might be due to its high speed. The Barwai Khwar has a TS of 800mg/L which is due to the overflow of water from paddies. The Mingora Khwar has a total solid of 600mg/L and that of Arunai is 240mg/L. The upper limits of TS recommended by the WHO is 500mg/L for drinking water allowing 1500mg/L (WHO, 1984).

6.    Total Suspended Solids

Total suspended solids also known as suspend matter, is that part of the solids that remains suspended in water and is due to clay, salts, finely divided organic and inorganic matters, plankton and microorganisms. The quantity of total suspended solid was maximum for Daral Khwar that was 580mg/L and minimum for downstream Kalam (40mg/L). Results in (table 2, Figure 6) shows that the total

suspended solid contents in almost all of the samples were beyond the drinking water standard (30mg/L) of the US Public Health water standard (USEPA, 1985).

7.    Total Dissolved Solids

Total Dissolved Solids (TDS) are the residues left after evaporation of water sample at 103-105oC. In water total dissolved solids are primarily inorganic salts with small concentration of organic matter. The principal ions contributing to total dissolved solids are mainly carbonate, bicarbonate, chloride, sulfate, phosphate and nitrates of sodium, potassium, calcium and magnesium (Mehmood, 1997). TDS in water may originate either from natural sources or sewage etc. However the major contribution to TDS is the natural contact of water with rocks and soil.

High concentration of TDS influence the quality of water such as taste, hardness, tendency to incrustation, and density of water. It affects osmorgulation of fresh water organisms and reduces the solubility of gases, water with low TDS level may also be unacceptable because of its flat, insipid taste.

The TDS value of all the samples ranges from 100-480mg/L (table 2, Figures 7) which are below the limits of 500-750 mg/L limits of the US Public Health Standards for drinking water also recommended by the WHO.

8. Alkalinity

Alkalinity of water is actually its capacity to neutralize a strong acid. A number of bases such as hydroxides, carbonates, bicarbonates, phosphates, nitrate etc. contribute to the alkalinity of water. However, in natural water carbonates, bicarbonates and hydroxides have been regarded to be the predominant bases. Alkalinity due to the presence of carbonate is generally known as phenolphthalein alkalinity, while alkalinity due to the presence of bicarbonate is known as methyl orange alkalinity which represent the temporary hardness. Total alkalinity can be defined as the addition product of phenolphthalein alkalinity and methyl orange alkalinity.

The analytical results (table 2, Figure 8) of water of the Swat River and its tributaries show that their alkalinity ranges from 4-14mg/L which is below 30mg/L, the upper limit recommended by US Public Health Standard for water quality.

9.     Hardness

Hardness can be defined as the sum of polyvalent cation present in the analyzed water sample. Calcium and magnesium are the main cations which imparts hardness. However, to a lesser extent cations like iron manganese and strontium also contribute to the hardness of natural water (Trivedi and Raj, 1992). Traditionally hardness is a measure of the capacity of water to react with soap. In other words hard water requires more soap to form lather. There are two types of hardness, temporary and permanent. Temporary hardness is due to the presence of bicarbonate of calcium, magnesium and other bivalent cations. This is also known as carbonate hardness and can be removed by boiling. The permanent hardness (non carbonate hardness) is due to the presence of sulfate and chlorides of calcium and magnesium. The hardness of water increases with the increase in polyvalent cations. For practical purpose the hardness of water can be classified as given in table 3.

The principal natural source of hardness in water is sedimentary rock and runoff from soil.

In the United States and the developed nations, the incidence of many chronic diseases, particularly cardiovascular diseases is associated with various water characteristics related to hardness (National Academy of Science, 1977). Hard water is not suitable for bathing, washing and is also corrosive in nature and deposits scale. Within certain limits hardness also imparts a bitter taste. The results obtained for water of samples are presented in (table 3, Figure 9) which are in the range of 10-61 mg/L and are excellent in nature compared to 500mg/L the upper limits proposed by WHO.

10.     Dissolved Oxygen

The extent of dissolved oxygen (DO) content shows the health and ability of the water to purify itself through biochemical process. The main source of dissolved oxygen in water is its diffusion from air and photosynthetic activity in water due to aquatic plants.

The solubility of oxygen in water generally depends upon the temperature, water movement, salinity and pressure. Oxygen is only a portion of the dissolved gases in water. Fortunately, the concentration of the oxygen is 38% of the dissolved gases. Dissolved oxygen is considered as the necessary element to support fish and aquatic life. It is also an indicator of water treatment and an important factor in corrosivity. In fresh water the dissolved oxygen reaches upto 14.6mg/L at 0^oC and approximately 9.1, 8.3 and 7mg/L respectively at 20^oC, 25^oC and 35^oC respectively.

The low concentration and continuos variation in DO makes it less important parameter for drinking water. But it takes the prime importance when the corrosivity and aquatic life is considered. Fish depends upon dissolved oxygen for respiration. When the DO level drops below 5ppm, the more desirable species of fishes such as Trout and Brass leave the area and only coarse type of fishes predominates and when the oxygen contents drops to 2ppm, fishes disappear and the environment can dwell only by anaerobic species. At the total depletions of DO anaerobic decomposition takes place with the production of gaseous byproducts like CO², CH⁴, H²S and Mercaptanes. The sulphide compounds cause foul odors and react with metal in the water to form black precipitate resulting black water (Trivedi and Raj, 1992).

The DO values in all the samples varied from 5.9 – 10 mg/L while the minimum requirement for aquatic life according to the WHO standard is 5 mg/L. The results obtained for DO are presented in table 4, (Figure 10).

CHEMICAL CHARACTERIZATION OF WATER FROM SWAT RIVER AND ITS T TRIBUTARIES

11.     BIOLOGICAL OXYGEN DEMAND:

BOD is the amount of oxygen consumed by microorganisms, during the stabilization action of the decomposable organic matter under aerobic conditions. BOD test is a bioassay to measure the oxygen consumed by living organisms utilizing the organic matter contained in water and the dissolved oxygen of water as well. The amount of BOD is directly proportional to the organic matter present in water. If there is more of the oxidizable organic matter present in water more of the amount of oxygen is required to degrade it and vice versa. In other words more the oxidizable organic matter more the BOD and vice versa (De Zuane, 1992).

The BOD value for all the sample ranged from 0.94 - 11.6 mg/L (table 4, Figure 11). All the samples except Mingora Khwar (11.6 mg/L), Barikot Bridge (9.6 mg/L) and Pulchawkai (5.86 mg/L) have according to the WHO recommended

BOD maximum permissible limits is (5 mg/L).

12.     Chemical Oxygen Demand.

Chemical Oxygen Demand (COD) is the measure of oxygen equivalent of that portion of the organic matter that is susceptible to oxidation by a strong chemical oxidant (selected for a standard method). For measuring the chemical oxygen demand, dichromate is usually used as oxidant with 50% sulfuric acid which provides the anhydrous conditions.

COD is an extremely useful tool for describing the nature if water especially in the case of industrial waste and is very practical in the determination of domestic waste in polluted water. The COD value for the samples analyzed ranges from 5.45mg/L (Table 4, Figure 12) against WHO permissible limits of 4 mg/L, which shows that COD for most of the samples is well above the international standards.

Ammonia is generally present in surface water, underground water and domestic sewage water. It is produced largely by the decomposition of nitrogen containing organic compounds and hydrolysis of urea. In water bodies it is produced naturally by the reduction of nitrates under anaerobic conditions. Free ammonia almost invariably originates from animal wastes and the quantity can range from 0.02 mg/L in surface water to 100 mg/L in the sewage discharges (Trivedi and Raj, 1992). Ammonia is extremely toxic to fish and should be present at practically below 0.2mg/L. Value of above 2 mg/L or high concentration is usually an indication of serious organic pollution (Chapman 1992). In aerobic conditions ammonia may be oxidized to nitrite and eventually in nitrates representing the most readily available form of nitrogen for higher plants.

Results obtained from the samples analyzed are presented in table no 4, (Figure 13) where the quantity of ammonia ranges from 1.34 - 11.6 mg/L for different localities.

14.     Nitrite:

Nitrite is a salt or ester of nitrous acid formed by the action of bacteria upon ammonia and organic nitrogen. Nitrite occurs in very low concentration in natural water and has no mineral source. It is formed as an intermediate during denitrification and nitrification reactions.

Nitrites dilates blood capillaries at higher doses while in lower doses it causes methemoglobinemia. Considerable amount of nitrites is an indication of sewage/bacterial contamination (US EPA, 1985).

The nitrite concentration in the analyzed samples ranged from 0.13 – 12.09 mg/L (table 4, Figure 14) except the sample no. 9 all are below the limits (10 mg/L) proposed by the WHO.

15.    Nitrates

Nitrates are the salts or ester of nitric acid or an end product of the aerobic stabilization of organic nitrogen.

Sources of nitrates are mineral deposits, soils, sea water and atmosphere. Nitrates are used as a fertilizers, as a food preservative and as an oxidizing agent in the chemical industry Partial reduction of nitrates into nitrites is carried out by Saliva in human of all the ages and in the gastrointestinal tract in infants during the first trimester. Therefore babies upto three months of ages are more susceptible since they transform 100% of ingested nitrates to nitrites, whereas only 10% of the ingested nitrates are expected to be transformed in the adults and children. The nitrites have vasodialatory/cardiovascular effects at high doses and cause methemoglobinemia at lower doses (NAS, 1977 and US EPA, 1985).

Results obtained from the analysis of samples are presented in table 4, (Figure 15), which are in the range of 0.1 – 2 mg and are below the limits (45 mg/L) proposed by WHO for drinking water.

16.    Chlorides

Chlorides giving rise to 0.05% share to the lithosphere, are the compounds of chlorine. They are widely distributed in nature, generally in the form of sodium chloride, potassium chloride and calcium chloride. They remain soluble in water and are unaffected by biological processes (Mehmood, 1997).

Chlorides are the most abundant anoins of human body and contributes significantly along with their associated cations, to the osmotic activity of the extra cellular fluid

An average 88% of the chlorides in human body is extra cellular. A normal human body of 70kg weight contains 81.7gm of chloride and 45 liter of water. Chlorides for drinking water contribute to less than 2% of the total daily dietary intake (WHO, 1984). High concentration of chlorides gives an undesirable taste to water. High chloride concentration is injurious to agricultural crops, corrosive to metallic pipes and engineering structures. However, a level upto 1000 mg/L is safe for human consumption. The desirable value of chloride in drinking water is less than 25 mg/L while the maximum permissible level is 250 mg/L. Results of the samples analyzed are presented in table 4 (Figure 16), which are in the range of 5.6 - 21.8 mg/L. The minimum for Barwai and the maximum for Mingora Khwar which are in the desirable limits 25 mg/L proposed by WHO.

17.    Phosphates

Phosphates are mainly the salt of phosphoric acid. In nature they are found in phosphate rocks. They constitute the inorganic part of bones and teeth.

Phosphate are used as chemical fertilizers, for production of special glasses, chinaware, baking powder and detergent. The daily average intake of phosphorus is approximately 1,500 mg with 70% absorbing rate as free phosphates. Phosphorus occurs in water almost safely as phosphates (De Zuane, 1992).

In water the main sources of phosphates are industrial effluents, domestic sewage, soap, detergents and fertilizers. Phosphate in water interface in lime softening process, aid in hard scale formation in water boilers and contribute to eutrophication. All the samples analyzed for phosphate (table 4, Figure 17) have the value from 1.67 - 12.71 mg/L which are above the standard 0.4 mg/L and at the maximum of 5 mg/L standards set by the European community, 1980.

18.    Sulphides

Sulphides are generally present in underground water and surface water at low concentration while it is common in hot Springs and waste waters coming from the decomposition of organic matter, sometimes from the industrial waste, but mostly from the reduction of sulphates (De Zuane, 1992).

The presence of sulphides may be regarded as an index of organic pollution. The sulphides are very toxic, corrode metal directly or indirectly. They are oxidized biologically to H₂SO₄. The sulphides concentration <0.05 mg/L cause complete mortality of fish (Anon., 1976).

All the samples of Swat river have the sulphide concentration 0.8 - 12.29 mg/L which is above the NEQS value of 1 mg/L for municipal and industrial waste water. Results are presented in Table 4, (Figure 18). As the pH of the Swat river is in the range of 7.08 - 8.23 and the concentration need not to be considered if the pH is less than 10. This is because at lower pH. Sulphides exist as non ionized molecule of hydrogen sulphides (H₂S) and hydrosulphide (H₅) with negligible concentration of sulphide ions S-- (Chapman, 1992).

19.    Sulphates

Sulphates are the salts or esters of sulphuric acid. Sulphates occur in all the natural water in appreciable quantities. They are final oxidized stage of sulphides, sulphites and thiosulphates or in the oxidized state of organic matter. The main sources of sulphates are domestic sewage and industrial effluents. Water having 500 mg/L or more sulphates has a bitter taste and causes diarrhea and dehydration (NAS, 1977). Below 500 mg/L it should be considered safe for health. The analytical result for sulphates contents of the water samples presented in table 4 (Figure 19) shows that its concentration ranges from 37.84-330 mg/L while the upper limit for sulphate according to WHO standards is 250mg/L for drinking water (WHO, 1994).

20.    Sodium

As a natural constituent of water, Sodium occurs much less as compared to calcium and magnesium. Its main source in water is the weathering of rocks. Its concentration is increased by pollution sources such as rock salt treatment, precipitation runoff, soapy solution and detergents. High sodium contents are harmful to persons suffering from renal, circulatory and cardiac diseases (Calabrase and Tuthill, 1980). If Sodium contents are above 200 mg/L water becomes salty. The high concentration of sodium check the biological diversity due to osmotic stress, while high sodium contents in irrigation water brings about pudding of the soil because of this water intake of soil gets reduced and it becomes hard in which germination of seed become difficult and the roat respiration is impaired (Mehmood, 1997).

The sodium contents in the samples from Swat River (Table 5, Figure 20) were in the range of 0.64 – 8 mg/L, which is below the maximum allowable concentration (200 mg/L).

21.    Potassium

Potassium is an essential nutritional element for humans, animals and plants. It is the seventh most abundant element constituting 2.4% of the earth crust (De Zuane, 1992). Potassium is extensively used in fertilizers, glass industry and chemical industry. The higher amount of calcium causes taste problems with a threshold of 340mg/L and causes hyperkalemia. The results of all the samples collected are presented in table No 5 (Figure 21), are within the range of 0.1068- 24.12 mg/L compared to 12mg/L as a maximum admissible level of European Community.

CONCENTRATION OF SOME METALS IN THE WATER OF SWAT RIVER AND ITS TRIBUTARIES.

22.    Copper

Copper is commonly found in earth’s crust in the form of sulphides, oxides and rarely as metals. Other sources are: copper wire mills, coal burning and steel producing industries.

Copper is an essential element of human nutrition since it is required in many enzymatic reactions. Copper is not a cumulative systemic poison. Experiments have shown that its oral intake upto 30mg even for many days has not caused poisoning (De Zuane, 1992). In water Copper is normally avoidable because of its taste at a threshold concentration of 1- 2 mg/L. High concentration of copper i.e. 5-8mg/L make the water undrinkable. At values above 1mg/L green stains appears as a reaction of soap with copper.

Results Samples analyzed for Swat river and its tributaries are presented in table 5 (Figure 22) are in the range of 0.04 – 0.2 mg/L while the WHO permissible limit is 1 mg/L (WHO, 1984).

23.    Cadmium

Cadmium is a soft blue metal. In nature cadmium occurs in Zinc, Copper and lead ores. The compounds of lead such as Chlorides, nitrates and sulphates are soluble in water. It is used in electroplating, solders, batteries, television sets, as a yellow pigment, ceramics, photography and insecticides (De Zuane).

Cadmium causes "Itai Itai" or "Ouch Ouch" diseases in which bones of the patients becomes fragile. At high concentration cadmium causes kidney problems, anemia, bone marrow disorders and accumulates in body (de Zuane). The analytical results obtained for Cadmium in the water of Swat River are presented in table 5 (Figure 23) which are in the range of 0.04 – 3 mg/L is the US Public Health Standards for water quality.

24.     Lead

Lead is a very soft highly malleable, bluish gray metal. Primarily it is used in storage batteries, cables covering, plumbing, ammunition, in the manufacture of tetraethyl lead, tetramethyl lead, as a protection shield from nuclear reactors to x-ray equipment, in glass industry and in paints.

Natural water contains upto 0.8mg/L of lead. Other sources of lead is the exhaust gases of motor vehicles, that contains degraded product of tetraethyl lead and atmospheric precipitation.

Lead is a commutative body poison. The major biochemical effect of lead is its interference with heme synthesis, which leads to hematological damages (De Zuane, 1992). The results of all the samples analyzed for lead are presented in Table 5 (Figure 24), which are in the range of 0.06 - 0.8 mg/L i.e. quit high than maximum allowable limits of 0.05 mg/L.

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BACTERIOLOGICAL STUDY

Microbiological examinations are the indicators of potential water born disease and comprise the most potential part of quality control of water. The bacteriological examination of water emphasis on the hygienic quality of the water. In general the microbiological parameters of water are dependent upon the frequency and type of bacteria, viruses and Pothogenic protozoans. Three types of microorganisms are generally found in water.

1. Natural aquatic bacteria which include spirillum, vibrio, Pseudomonas, Achromobacter, Chromobacterium, and a few species of Micrococcus and Sarcina.
2. Soil dwelling organisms which are washed by rain into water bodies e.g. bacilli, streptomyces, a variety of fungi and saprophytic members of the enterobacteria such as aerobacter.
3. Organisms that normally live in the intestinal tract of humans, their livestock and pets e.g. Escherichia Coli, Strepto-coccus and Clostridium species.

Hygienically microorganisms of the first two groups have a little importance. However, the incidence of the organisms of the third group indicates fecal contamination by disease producing organism like Salmonella, Shigella, Vibrio, Cholera, intestinal parasites and Entroviruses. (Akhtar, 1988)

The most common and severe diseases of water born nature in the area are Cholera, typhoid and Paratyphoid and diarrhea and enteritis. Other water born diseases of the secondary importance include:

• Infectious Hepatitis
• Ascariasis
• Tularemia
• Ankylostomiasis (Hook Worm)
• Orzacentiasis (Guinea Worm)
• Schistosomiasis (Bilharzia)
• G.I outbreaks of obsecure etilogy
• Eye, ear, nose and throat infections

These infections and morbid conditions does not necessarily indicate water is the sole means of transmission and is not even responsible for the majority of cases in all the situations. Water quality is generally monitored by its contamination. The monitoring of fecal contamination of water bodies require the isolation and enumeration of containing organisms. Coliform bacteria have long been recognized as a suitable microbial indicator of drinking water quality. (Zuane, 1992)

Escherichia coli, a member of Enterobacteriaceae, and is characterized by possessions of the enzymes ß-galactosides and ß-glucuronidase. Artificially it can be cultured on 44-45^oC on complex media ferments lactose and mannitol. In nature it live as a symbiotic prokaryote in the intestines of mammals and hence can abundantly be found in human and animal feces. In fresh faces it may attain concentration of 109 per gram. It is found in sewage treated effluents and all natural waters and soils subjected to recent fecal contamination, whether from humans, wild animals or agricultural activity. (WHO, 1997)

The most commonly used methods for the isolation of indicator organisms are multiple-tube (MT) or Most Probable Number (MPN) method, Membrane Filtration (MF) method and presence absence test. (WHO. 1997)

The fecal coliform was determined in the water samples of River Swat are presented in table 26

COLIFORM COUNTS AND THE EXPECTED RISK SITUATION IN RIVER SWAT AND ITS TRIBUTARIES.

WHO COLOR CODE SCHEME FOR E. COLI IN DRINKING WATER.

Results of our findings (Table 6) shows that the water of River Swat upstream Kalam has the least coliform count i.e. 17 and can be taken nearest to the water of low risk value (Table 7). Water downstream Kalam and that of Chail Khwar has the coliform count 45 and 35 respectively and can be placed in the water of low risk type. Water of River Swat at other sampling sites and that of its tributaries can be placed in the high-risk type, except the water of Jambel Khwar having more than 1800 coming under very high-risk value. (WHO, 1997)

Comparison of the results obtained (table 6) and the standard set by WHO (WHO,1997) concludes that the water of Gabral River (Up stream Kalam) is highly preferred drinking water followed by that of Chail Khwar. Water on other sites has a low to high-risk limits except the water of Jambil Khwar which is completely unfit for drinking.

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CONCLUSIONS

To know the overall spectrum of pollutants in Swat River, it is imperative to conduct similar surveys in different seasons of the year. However it can be concluded from the present survey that

1. Whatsoever the sampling place on River Swat or its tributaries may be, the water has a potability risk ranging from mild to high and the risk generally increases downstream along the river.
2. Organic contamination increases gradually downstream and severely with the discharge of municipality waste downstream Mingora.
3. Total solid content proves that accelerated erosion is very serious problem, not only it impair the water quality but also decrease soil fertility and causes silting problems in the stream and water.
4. Water of Jambil Khwar is highly polluted and must not be used for household and livestock consumption.
5. The disposal of Jambil Khwar to Swat River in the present state is a threat both to the health of Swat River and the health and socio-economic conditions of its users.

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RECOMMENDATIONS

• To protect and conserve the water of Swat River it is recommend that the following steps should be adopted not only to improve the quality and quantity of water but also to improve the health of water bodies and thereby the socio-economic condition of the people of Swat.

• The sources of fecal contamination i.e. hotels, households and industrial waste needs immediate management.

• Organizations working on the protection and conservation of River Swat need to be strengthened for evolving strategies and conservation measures.

• Countrymen need awareness about their role in the conservation of Swat River.

• Laws regarding illegal constructions near the river course must be implemented.

• Water of Jambil Khwar and other such bodies need proper treatment before its disposal into the river.

• If treatment of contaminated water is not feasible may be diverted for irrigating cropland.

• General surveillance/monitoring of the pollutants is a need on continuous basis.

• Watershed management is necessary for continuous recharge and delimiting the solids contamination.

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WHO. 1997. Guidelines for Drinking Water Quality Vol. 3 Geneva Switzerland.

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