Theme - Drinking Water Quality
WATER QUALITY: GUIDELINES AND ASSESSMENT OF RISK
School of Environmental Sciences, JNU, New Delhi 110 067
The quality of water, whether it is used for drinking, irrigation or recreational purposes is significant for Health in both developing and developed countries worldwide. Water quality can have a major impact on health, both through outbreaks of waterborne diseases and by contributing to the background rates of the diseases. Accordingly, countries develop water quality standards to protect public health. The WHO has developed a series of normative guidelines for assessment of health risk and hazards through water. These principal guidelines are intended to assist countries in establishing effective national or regional strategies and standards. These guidelines should be updated as scientific and managerial developments to ensure that they continue to be based on the best available evidence in each country based on their climate, geography, topography and customs.
STUDY OF GROUND WATER QUALITY IN THE PERIYAR DISTRICT OF TAMILNADU, INDIA
School of Environmental Sciences, JNU, New Delhi 110 067
The study evaluates the water quality of the Periyar district in Tamilnadu. Systematic sampling of groundwater has been carried out in different seasons from 1997 to 1999 in the entire Periyar district of Tamilnadu. Groundwater is colorless, odorless and are alkaline in nature. EC and TDS shows are god to moderate in nature. The water chemistry shows distinct variation in space and time. Na+K-Ca-Mg-Cl+ SO4-HCO3 is the dominant hydrogeochemical facies. SO4, NO3 and PO4 concentration are higher showing the influence of the anthropogenic sources. SAR, RSC, Na%, CR, TH etc shows that the water is generally good for domestic, agricultural purpose and are not good for long distance transport. Geochemical studies reveal the variation in the (H4SiO4/ HCO3), (F/Alkali) and (F/Ca+Mg) molal ratios and the ionic strength of the groundwater in the aquifer. Here the Fluoride concentration is generally lower than prescribed limit except few areas where the concentration exceeds 1.5ppm.
TECHNOLOGICAL ADVANCEMENTS IN ENVIRONMENTAL BIOTECHNOLOGY TO ASSESS WATER QUALITY
Rita Kumar and Shikha Rastogi
Centre for Biochemical Technology, Delhi University Campus,
Mall Road, Delhi 110 007
Water flows are not steady or uniform, but vary from one hour to another, from day to day, from month to month and from year to year. One major culprit responsible for this is the discharge of pollutants from a variety of sources into the water streams. The discharge of oxygen consuming materials, deplete the dissolved oxygen (DO) of receiving waste-waters. Marked depletions in DO levels can cause major changes in the aquatic flora/fauna in water bodies. Therefore, all the industrial discharges (major quenchers of DO) need to be monitored before their release into the flowing water bodies. Biochemical Oxygen Demand (BOD) is one such method for predicting the rate of consumption of DO by microorganisms in a water body. This test is an essential part of assessing the potential for deoxygenation of the receiving waters. The conventional BOD test performed world wide as per the guideline of American Public Health Association (APHA, 1998) is a cumbersome technique having some major disadvantages. First and foremost amongst them is the use of non-standard seeding material (i.e. the microorganisms which are procured from sewage). We have successfully overcome this problem by formulating a uniform, dehydrated microbial mixture to be used as seeding material in BOD analysis. This product named as BODSEED has been successfully launched in the marked. To add here, the Bureau of Indian Standards (BIS) has approved the use of synthetic seeds in BOD analysis. This product is first of its kind in the Indian market. Though this microbial composition reduces the possibility of controversy in BOD results and makes BOD analysis an easy, clean and conventional laboratory test, it needs to be revived a day before conducting the experiment. An endeavour to develop a ready-to-use seeding material for BOD analysis resulted in the development of BODBEADS. This product is first of its kind in the global market and an International patent has been granted for this technological outcome. Another major drawback of the conventional BOD test is that it requires 3-5 days to arrive at a plausible conclusion. The test is too slow to provide timely information to the operator for control purpose. Therefore, for real time monitoring of the BOD load in waste-waters, we are in the process of developing a mixed culture based versatile BOD biosensor.
Once, we have an insight into the waste-water in terms of its oxygen requirement, we need to treat/control it. Presently, chemical treatment methods are utilized to control waste-waters. But, the agony of this method is that the chemicals used for treatment purposes also add to the pollution load. Biological treatment of wastes is an alternate approach relying on some basic microbial metabolic fundamentals. Collectively, microbes exhibit unparalleled metabolic diversity and adaptability, allowing them to survive in environment incompatible with large life forms. Microbes produce energy and carry out metabolism from a tremendous variety of organic materials. Several viable technologies for the efficient and effective treatment of waste-waters have been developed by our group. Out of these, two technologies viz., ALKANEUTRI and PHENOTREAT are ready for up scaling followed by commercialization. We are also heading towards the development of a few more tailor made microbial packages for treatment of untackled organic wastes.
GROUND WATER QUALITY ON EITHER SIDES OF THE RIVER PONNAIYAR, TAMIL NADU
S.Chidambaram1, L. Ragunathan2, K. Srinivasamoorthy1, P. Anandhan1 and S.Vasudevan1
1 Department of Geology, Annamalai University, Chidambaram.
2 Water testing lab, PWD, Pondicherry
Settlements and civilizations of mankind started on the river banks. This was due to the fact that water played a key role in their day-to-day needs, for domestic and agricultural. The excess extraction of water for the industries and the development of aquaculture along the coast has lead to the deterioration of water quality. To study the nature of such affect along the river course on its either sides, a study was conducted along the river Ponniyar located along the east coast of Tamil nadu. Total of twenty groundwater samples were collected ten on the north bank and ten in the southern bank of the river. The samples collected were analysed for different parameters like major and minor ions along EC, TDS and pH. The ratios like Cl/HCO3 and Na/Cl were calculated to find out the influence of sea water and the weathering in the water samples. Standard plots of USSL, Gibbs and Johnson were used to find out the agricultural utility, factor controlling water chemistry and the facies of the water. It was found that the northern part of the bank was more contaminated than the southern region. This was due to the influence of agriculture, tributaries back waters and to certain extent lithology.
GROUND WATER QUALITY IN THE COASTAL TRACT FROM PUDUCHATIRAM TO CHIDAMBARAM, EAST COAST OF INDIA
P. Anadhan, R. Manivannan, V. Mala and N.Ganesh
Department of Geology, Anna Malai University, Annamalai Nagar - 608 002.
The concentration of the ions in the water determines the quality and its utility Higher concentration of the dissolved ions affects the potability, palatability drinking and the irrigation needs of the dependent society especially in the coastal tracts. The hydrogeochemical studies carried out in the study area in two seasons reveals the dominance of ions in the following order CleS04~HC03 and Na<Mg<Ca<K. Ground water is colorless with slight odour and are alkaline in nature. The abnormal concentrations of Cl, SO4 and Na are observed in the entire study area m different seasons as well as in two different aquifers. The spatial distribution of hydrogeochemical facies indicates the predominance of Cl and SO4 in all the high salinity ground water in both the seasons. Predominant geochemical water type here is Na-Cl and Na+K-SO4. The ground water in these areas are Saline, having permanent hardness, low Na%, RSC and SAR and high C.I. The secondary leaching process from the precipitated leachates, fertilizer and anthropogenic impacts clue to recycling of agriculturally used water and return flow controls the chemistry of the ground water. Nutrients levels are with in the limit and are increasing in the post-monsoon season. Sea water intrusion is suspected to have a partial impact in the ground water chemistry in this region. Hence the abnormally higher concentration of TDS, Cl, SO4 and Na caused due to anthropogenic impacts made these water unsuitable for drinking water purpose except for irrigation and industrial purpose (WHO 1992). So it is essential to evolve a suitable precautionary methods to avoid the deterioration of the water quality which may not be even useful for irrigation purpose if this situation continues.
HYDROGEOCHEMICAL SURVEY DATA: UTILITY IN WATER QUALITY ASSESSMENT
Geology Department, Delhi University, Delhi - 110 007
Water forms an important commodity for the very survival of humanity. It has no replacement for drinking and agricultural food production. In natural condition, water exists in different types as fresh water, brackish water, saline water, brine water etc. The nature of water molecule though simple, provides enough scope for different elements including toxic, under suitable pH and Eh conditions, to go into solution in various quantities. Water contamination being one of the problems, takes place in surface environment mainly due to the anthropogenic input and subsurface environment due to the interaction with different types of rocks, metallic ores or toxic metal rich sediment layers. So, water whether on surface or subsurface may become unusable for drinking and other purposes due to these reasons.
This change in the quality if due to the dominant ions, may be perceived easily on the basis of taste or odor etc. But the subtle changes in the concentration of different trace elements, which may become toxic, may not be easily perceived. This is one of the problems being faced by the vast majority of the population in the form of fluoride, arsenic, lead etc. The source for such toxic levels may be natural or anthropogenic (particularly in urban areas). Irrespective of the source, the effects will remains the same that is the human health. Many treatment plants are in operation in urban areas to overcome this problem but in rural areas it (particularly natural contamination) remains a problem.
Present paper tries to utilise the data generated during geochemical survey in parts of Rajasthan to assess the water quality. The survey has successfully demarcated the areas, potential for base metal deposits particularly low grade in many cases on the basis of soil or stream sediment data. The ground water samples collected in addition to soil, stream sediment and rock during these surveys were analysed for Cu, Pb, Zn, Mn, Fe, Co, Cr, Ni etc. The data shows fairly high values for base metals and also Mn & Fe in certain areas. The contribution is assumed to be from the low-grade deposits. Since major part of the population in these areas are dependent on ground water for drinking and agricultural purposes and the recorded concentrations are much above the prescribed limits, a proper survey is suggested to be carried out to assess the water quality in terms of human health.
TEMPORAL VARIATION OF GROUNDWATER QUALITY IN AND AROUND THE TANKS OF PALAR BASIN, TAMIL NADU
G. Ravikumar and P. Srinivasagopalan
Centre for Water Resources, Anna University, Chennai
The water quality studies plays important role in the usage of the water. The irrigation being the lifeline of our country. The water used for irrigation purpose Stored in the tanks and regional ground water level is there by increased and it also serves for the direct usage of the water for irrigation. An attempt has been made in this study to know the ground water quality around the system tanks in Palar basin in North Arcot, Tamil nadu. 10 samples were collected in each season pre and post monsoon in the Ayacut area of Palar river basin studied for its temporal variation. The water collected were analysed for Ca, Mg, HCO3, SO4, Cl, PO4 and NO3. The parameters like EC, pH and TDS were also studied. it revels that premonsoon samples in groundwater shows higher concentration which was displayed by EC and TDS. The tanks contain water only in the monsoon season. In order to get an idea of the surface water quality and know their relationship. 14 surface water samples were collected and analysed.
GROUNDWATER QUALITY AND HYDROCHEMICAL FACIES IN RELATION TO THE TERRAIN MORPHOLOGY AND WATER TABLE SITUATION A CASE STUDY FROM FIROZPUR JHIRKA NAGINA REGION, GURGAON, HARYANA
V.N. Bajpai and S. Nayyar
Department of Geology, University of Delhi, Delhi 110 007.
Groundwater quality and hydrochemical facies have been determined for the shallow groundwaters in the Firozpur Jhirka Nagina region of Gurgaon district. The region has been morphologically classified on Landsat images into rocky tract (structural ridges of quartzite), pediment (weathered rock in foothill region covered with alluvium) and valley fill (alluvium). The groundwater quality has been assessed on the basis of chemical analysis of 32 samples presented on the trilinear diagrams and on the cantour maps of specific electrical conductance, sodium and chloride. Four major hydrochemical facies calcium bicarbonate type, sodium bicarbonate type, calcium chloride type and sodium chloride type are indicated on trilinear diagram. Out of these, the sodium carbonate and sodium chloride are the dominant facies. In general, the water quality is fresh and potable in quartzite ridges and pediments. The specific electrical conductance, sodium and chloride values range as 500 2000 microsiemens, 17 375 ppm, and 280 760 ppm respectively. The higher values are towards the pediment valley fill contact. In valley fill, the water is saline to very saline, indicated by the ranges of specific electrical conductance, sodium and chloride as 4000 16,000 microsiemens, 300 6300 ppm, and 300 10,000 ppm respectively. Saturation indices of calcite, halite and gypsum are low in ridge and pediment areas. However, they are high in valley fill zone. Two distinct pockets of oversaturation in valley fill zone are noticed in all the saturation index contour maps one in the north (NE of Nagina in Muhamadnagar Hasanpur Nuh region) and the other in the south (S of Firozpur Jhirka in Jormalbas Raoli region). These zones are in conformity to those noticed in the specific electrical conductance, sodium and chloride contour maps. Electrical resistivity plots also indicate the fresh water in the quartzite ridge pediment region (resistivity=50-80 Ohm.m) and highly saline water in the valley fill region (resistivity=3-6 Ohm.m). The water quality and oversaturated mineral zones have been found not only related to morphological variations but also to water table gradient. The fresh water in the rocky tract pediment region is because of recharge waters (bicarbonate waters), flushing the region due to their flow with high gradient towards the valley fill. The regional water flow in the valley fill initially towards NE and finally towards the Kotladhar water body 2 in the NW also gets sluggish, giving rise to stagnant and water-logged conditions. This has further resulted into location of high salinity (sulphate and chloride waters) and oversaturated mineral zones. More ion exchange between clays and groundwater has also contributed to concentration of sodium in valley fill waters. The waters have thus hydrochemically evolved towards very saline following Chebotarev sequence. It is therefore suggested that the maximum water may be pumped out through battery of wells installed in the ridge pediment region in order to have fresh water supply and avoid the flow of water towards the valley fill zone.