research article water quality assessment of the central...

Research ArticleWater Quality Assessment of the CentralHimalayan Lake Nainital

Madhuben Sharma

University of Petroleum and Energy Studies Bidholi Dehradun Uttarakhand 248007 India

Correspondence should be addressed to Madhuben Sharma madhubensharma06gmailcom

Received 14 July 2014 Revised 28 October 2014 Accepted 20 November 2014 Published 10 December 2014

Academic Editor Paul M Bradley

Copyright copy 2014 Madhuben SharmaThis is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

The Nainital Lake situated in the central Himalayas of India is an important water body and a major tourist spot This study aimsto identify factors or processes that determine the water quality of the lake For this purpose water samples from two differentpoints were collectedmdashhighly polluted (Mallital) and least polluted (Tallital)mdashto represent the actual level of pollution in the lakein four different seasons (January April July andOctober)The collected samples were analyzed for different physical and chemicalparameters In order to assess the state of the lakersquos water quality the samples were compared with the standard water quality valuesTurbidity electrical conductivity total alkalinity and heavy metal (lead iron and copper) concentration were found to be abovethe desirable limit of the prescribed national and international standards in all four seasons at both Mallital and Tallital Reasonsaffecting the water quality were found to be natural (thermal stratification and lead-bearing rocks) and anthropogenic (domesticsewage runoff and illegal construction activities in the vicinity of lake) Various lake restoration alternativesinterventions havebeen suggested that can lead to an improvement in the lakersquos water quality such as afforestation phytoremediation and sedimentbasin

1 Introduction

Nainital city is one of the major tourist attractions in thenorthern part of IndiaThe lake provideswater to 40000 localinhabitants [1] and thousands of tourists visiting it every year[2] who use the water for different purposes like drinking andfor recreational activities [3 4] Increasing local populationlogarithmic increase in the tourist flux in Nainital and theconcomitant mushrooming of a large number of hotels in thecatchment area have severely affected the water resources andbiodiversity of this watershed [5 6]

According to Singh et al [7] open sewers disposinglarge quantities of sewage in the lake are definitely caus-ing a detrimental effect on the lake water quality Otheranthropogenic activities such as illegal construction litterdomestic discharge and recreational use of lake water aremajor concerns for sedimentation and eutrophication of thelake water [1]

Thus considering it as imperative this comprehensiveprimary water quality monitoring study of the Nainital Lakehas been undertaken The main objective of this paper is

to assess the state of water quality of the Nainital Lake bycarrying out a comprehensive monitoring exercise to identifythe contributing factors for the existing water quality For thispurpose water samples were collected from a highly pollutedand a least polluted site of the lake 18 physicochemicalparameters were analyzed to understand the limnology of theNainital Lake Various possible measures that can be put inplace to maintain the desired water quality have also beendiscussed

2 Materials and Methods

21 Study Area TheNainital Lake is a natural kidney-shapedtectonic warm monomictic-type lake situated at 29∘ 241015840Nlatitude and 79∘ 281015840 E longitude [5] It covers a surface areaof 48 hectares The maximum and mean depths of the lakeare 273m and 162m respectively [2] It is divided into twosubbasins (Mallital and Tallital) by a 100m wide transverseunderwater ridge 7m below surface [5] Mallital (northbasin) is a highly polluted site due to intense boating activityandNaina DeviMandir drain emptying into it Tallital (south

Hindawi Publishing CorporationAdvances in Environmental ChemistryVolume 2014 Article ID 473074 5 pageshttpdxdoiorg1011552014473074

2 Advances in Environmental Chemistry

Table 1 Drinking water quality standards units analytical method and recommending agencies (source [8ndash10])

Water quality Unit Analytical method Indian standards (desirable) andrecommended agencies

pH pH unit pH meter 65ndash85 (BISICMR)Turbidity NTU Turbidity meter 5 (BIS)Dissolved oxygen mgL DO meter 5 (ICMR)Electrical conductivity 120583scm Conductivity meter 300 (ICMR)Total dissolved solid mgL TDS meter 500 (BIS)Total suspended solid mgL Gravimetric 500 (WHO)

Temperature DegreeCelsius Portable thermometer mdash

Biochemical oxygendemand mgL Winkler azide method 5 (ICMR)

Total hardness CaCO3 mgL Titrimetric 300 (BISICMR)Total alkalinity CaCO3 mgL Titrimetric 120 (ICMR)Chloride mgL Argentometric 250 (BISICMR)Sodium mgL Flame photometer lt20 (WHO)Potassium mgL Flame photometer 10 (WHO)Phosphate MicrogramL UV spectrophotometer mdashLead mgL Atomic absorption 005 (BIS)Copper mgL Atomic absorption 005 (BIS)Iron mgL Atomic absorption 03 (BIS)Zinc mgL Atomic absorption 5 (BIS)BIS Bureau of Indian Standard WHO World Health Organization and ICMR Indian Council of Medical Research

basin) on the other hand is relatively less polluted Geology ofboth basins is one of the key interests for this studyThe lakersquosbasin is formed of folded and faulted rocks ofKrol andTal for-mation attributed to the Cambrian Age [11]The lake receiveswater from springs (Pardadhara andChunadhara) rainwaterand 22 inlet nullahs (9 are permanent which act as a majorconduit of polluted sludge and silt draining off into the lake)[1]The lake supports around 40000 local inhabitants presentin its catchment area hence anthropogenic activities likesurface runoff domestic sewage construction activities andagricultural activities have significantly changed the waterquality of the Nainital Lake

22 Sample Collection and Analysis Water samples werecollected from two sites of NainitalmdashMallital (L1) and Tallital(L2) (Figure 1) Fourteen grab samples were collected for eachmonth (January April July andOctober) from both the sitesIn order to collect representative samples a sampling stationnetwork was designed in such a way so as to cover wide rangeof factors such as drains and springs that influence the waterquality of the lake Water samples were collected in 2000mLpolyethylene sterilized bottles (cleaned with metal-free soapwashed with distilled water soaked in 10 nitric acid for24 hours and finally rinsed with ultrapure water) Watersamples were stored in an insulated ice-cooled containerand delivered to the laboratory on the same day All thesamples were kept at 4∘C to avoid physicochemical changesand interferenceThe sampling preservation transportation

Mallital (L1)

Tallital (L2)

Figure 1 Map showing the study area and surface water qualitysampling stations of Nainital Lake (source Google map)

and analysis of water samples were carried out accordingto the methods described in APHA-AWWA-WEF (1998)[12] The polyethylene bottles used for storing samples weresealed with tape to make the sample free from air contactSurface runoff domestic sewage and weathering of rockswere found to be responsible for influencing the physicaland chemical parameters of the Nainital Lake water A totalof 18 physicochemical parameters were analyzed in labo-ratory using standard protocol APHA-AWWA-WEF (1998)including total dissolved solids (TDS) total suspended solid(TSS) turbidity electrical conductivity (EC) phosphate totalhardness pH alkalinity temperature BOD DO Cl Na+ PbK Cu Fe and ZnWater quality parameters unit methods ofanalysis Indian standards and recommended agencies are allsummarized in Table 1

Advances in Environmental Chemistry 3

Table 2 Descriptive statistics of water quality parameters for Nainital Lake for all 4 seasons (January April July and October)

ParameterNainital Lake (Mallital) Nainital Lake (Tallital)

For all 4 seasons Mean plusmn Std deviation For all 4 seasons Mean plusmn Std deviationMaximum Minimum Maximum Minimum

PO4

minus3 018 009 0143 plusmn 0046 016 009 0123 plusmn 0036Temp 2200 1700 1950 plusmn 208 2200 1800 2050 plusmn 173DO 860 790 820 plusmn 029 720 400 577 plusmn 139pH 820 720 755 plusmn 047 820 740 775 plusmn 034BOD 350 280 325 plusmn 033 480 380 425 plusmn 041Turbidity 1600 600 1025 plusmn 464 1800 600 1050 plusmn 525TH 29000 19200 25000 plusmn 4153 39200 11200 24150 plusmn 1259TA 27800 23000 25350 plusmn 2156 15400 12000 14200 plusmn 1505TDS 42200 37500 40000 plusmn 2305 58200 35900 44325 plusmn 9829TSS 39000 28600 33800 plusmn 4492 41200 25800 34125 plusmn 6862Cl 1800 1100 1450 plusmn 288 1900 1400 16750 plusmn 262EC 58000 50000 53600 plusmn 3362 55000 50000 52500 plusmn 2886Na 320 242 279 plusmn 040 330 289 314 plusmn 018K 1457 1180 1282 plusmn 120 1124 1027 1057 plusmn 045Pb 34 24 028 plusmn 004 27 21 023 plusmn 002Cu 24 14 019 plusmn 004 22 18 020 plusmn 001Fe 73 62 068 plusmn 004 79 64 070 plusmn 006Zn 08 03 006 plusmn 002 07 02 004 plusmn 002

3 Result and Discussion

The different physicochemical parameters of the lake waterare discussed below and compared with WHOBISICMRstandards The descriptive statistics for both sites (Mallitaland Tallital) are presented in Table 2

The lake water appears to be alkaline in nature in allfour seasons with the pH value ranging between 65 and82 Maximum pH was recorded at Mallital in July andOctober and at Tallital in April Purohit and Singh [4] tooreported high pH in the lake for the said period (JulyndashNovember) Increase in photosynthetic activity of submergedand suspended algal population in aquatic ecosystemmay bethe reason for this increase in pH value

Total alkalinity recorded in theNainital Lakewater rangesbetween 230mgL to 278mgL at Mallital and between120mgL to 154mgL at TallitalThemaximumconcentrationof alkalinity was recorded during July season at both thesites During monsoon surface runoff brings organic matterand with decomposition of this organic matter carbondioxide is released resulting in the addition of carbonate andbicarbonate which also increases the alkalinity value

Dissolved oxygen (DO) is the indication of general healthof awater body DO recorded in thewater of theNainital Lakeranges between 79mgL to 86mgL at Mallital and between4mgL to 72mgL at Tallital The maximum amount of DOin the water of the lake was recorded during April at Mallitaland in October season at Tallital This can be explained bythe fact that during active photosynthesis more oxygen getsdissolved in the lake [13 14]

Biochemical oxygen demand (BOD) is a key parameterand it indicates the organic load in aquatic ecosystem

BOD value in the Nainital Lake ranges between 28mgLto 35mgL at Mallital and between 38mgL to 48mgL atTallital whichwaswithin the desirable limit of drinkingwaterquality standards for all four seasons

The minimum concentration of phosphate (9312 micro-gramsl to 8865 microgramsl) was recorded during Januaryat both the sites (Mallital and Tallital) of the lake Maxi-mum concentration of phosphate (16276 microgramsl) wasrecorded during April at Tallital and in October (18468microgramsl) at Mallital

Electrical conductivity (EC) varies between 500mgL to580mgL at Mallital and between 500mgL to 550mgL atTallital Maximum EC (580mgL) was reported at Mallitalin the month of April and (550mgL) in April and Octoberat Tallital EC in the lake is controlled by surface runoff insummer and subsurface runoff during monsoon and earlyspring Concentration of total suspended solids (TSS) variesfrom 286mgL to 390mgL at Mallital and from 258mgLto 412mgL at Tallital for different seasons Maximum con-centration was recorded at Mallital in April (390mgL) andin July (412mgL) at Tallital Total dissolved solid (TDS) inNainital Lake ranges between 375mgL and 422mgL forMallital and between 359mgL and 582mgL for Tallital Themaximum amount of TDS was recorded during July at bothsites This increased concentration of TDS in the NainitalLake was attributed to surface runoff Results for EC and TDSshow conformance with the previous study [15]

Presence of clay silt organic matter phytoplankton andother microscopic organisms causes turbidity in lake waterPresence of high turbidity indicates the presence of largeamount of suspended solids Turbidity in Nainital Lake wasrecorded in ranges between 6NTU to 16NTU for Mallital


and between 6NTU to 18NTU for Tallital The maximumturbidity (16NTU and 18NTU) in water was recorded duringthe month of July at both the sites Again this high tur-bidity during July can be attributed to particulate additionthrough surface runoff from the surrounding hills Alsoan increase in population and cultural activities leading tomassive deforestation and waste generation in the catchmentof Nainital Lake in turn leading to an increased concentrationof suspended solids can also affect the turbidity in theNainitalLake The mean turbidity values obtained for Nainital Lakewere in conformance with the values as reported in literature[4]

Total hardness recorded in the water of Nainital Lake forpresent investigation ranges between 192mgL to 290mgLand between 112mgL to 392mgL for both sites respec-tively The maximum concentration of total hardness inthe water of Nainital Lake was recorded during April atTallital (392mgL) High temperature evaporation of waterweathering of rocks and addition of calcium andmagnesiumsalts by means of plants and living organismwere found to becontributing factors for the hardness of the lake water

Concentration of potassium (K) varied from 118mgL to1457mgL for Mallital and from 1027mgL to 1124mgL forTallital Maximum potassium concentration was observed atboth the sampling sites during July It was found that duringrains wastewater drains (Nallahs) in the catchment area wereresponsible for the increased potassium concentration as therunoff consisted of decomposed organic waste and plantmaterial which increases the concentration of potassiumin the lake water Similar finding has been projected byTrivedy et al [16] Seasonally concentration of sodium (Na)in Nainital Lake varied from 242mgL to 32mgL and from28mgL to 33mgL for both sites respectively Chloriderecorded in the water ranged between 7mgL to 11mgL(Mallital) and between 14mgL to 19mgL (Tallital) Theconcentration of sodium and chloride in Nainital Lake didnot exceed the WHO and BIS recommended values

31 Distribution of Heavy Metals in Lake Water It wasfound that seasonally the concentration of lead (Pb) in theNainital Lake ranged between 021mgL to 034mgL forboth the sites (Mallital and Tallital) and maximum lead wasreported in October at both sites The reasons for increasedlead concentration were found to be anthropogenic activities(boat repairing painting) presence of automobile workshopon the banks of the lake and lead-bearing minerals presentin the catchment rock formation [15] During winter as thetop layers become cooler in comparison to the deeper layersthe sinking process starts which shows greater mixing duringwinter in comparison to summer (April) when it is thermallystratified In this study the concentration of lead obtainedwas higher than the permissible limit of BIS hence makingthe lake water unsuitable for drinking and domestic use Theunsuitability of such water is corroborated by Schwartz et al[17] who reported that high concentration of lead leads togrowth retardation in children

Copper (Cu) concentration varied between 014mgL and024mgL throughout the study period It was reported to be

Table 3 Suitable interventions for the remediation of the NainitalLake water

Srnumber Techniques Discussion

1 Afforestation

Control soil erosion from nearbyhills which further helps incontrolling turbidity of the lakewater

2 Phytoremediation

Growing common aquatic plantslike bulrush water hyacinthduckweed hydrilla and lotus inthe catchment area and inside theNainital Lake will help in theremoval of heavy metals from thesurface runoff and lake water

3 Sediment basin

Basin is rectangular in shapeformed by excavation or byconstructing embankment Itreduces water flow by trappingmaximum amount of sedimentshaving efficiency of settlingparticle of size up to 0005mmthereby making downstreamwater free from debris

highest in July at both sites Mallital recorded 024mgL andTallital recorded 022mgL respectively Leaching of metalsfrom the catchment soil and from market wasteeffluentinto rainwater [2] and then transporting into the lake waterincreased the concentration of copper in the Nainital Lakewater

Concentration of iron (Fe) ranged between 062mgL and079mgL It was found to be highest in April at Mallital(073mgL) and in January at Tallital (079mgL) Increasedconcentration of iron in itself is not a pollutant but it providesa favorable condition formany pathogenic organisms to growas they require iron to thrive

The concentration of zinc (Zn) varied between 002mgLand 008mgL for both sites and was reported to be withinthe desirable level as per BIS standards

Based on this study it was found that at both the sites ofNainital Lake (Mallital and Tallital) surface runoff and heavymetals (lead copper and iron) were the main contributorsof water pollution In order to control the surface runoffand for the rejuvenation of the Nainital Lake water suitableinterventions have been discussed in Table 3

4 Conclusion

The study reveals that turbidity total alkalinity electricalconductivity and heavy metal (lead copper and iron) werefound to be above the desirable limit of BISICMRWHOstandard in all four seasons at Mallital and Tallital The lakewater quality deterioration is caused by domestic sewagesurface runoff from nearby hills deforestation and naturalactivities (thermal stratification lead-bearing rocks) Suitablelake restoration measuresinterventions as mentioned aboveshould be adopted to reduce anthropogenic discharges into


the lake basin otherwise high levels of pollutants will bringabout a negative effect on the lives of the surroundingpopulation and their socioeconomic conditions

Conflict of Interests

The author declares that there is no conflict of interestsregarding the publication of this paper

References

[1] P Purushothaman S Mishra A Das and G J Chakra-pani ldquoSediment and hydro biogeochemistry of Lake NainitalKumaun Himalaya Indiardquo Environmental Earth Sciences vol65 no 3 pp 775ndash788 2012

[2] R Gupta P Bhagat M Joshi S Inaotombi and P K GuptaldquoHeavy metal pollution status of Lake Nainital UttarakhandrdquoIndian Journal of Scientific Research vol 1 no 1 pp 15ndash19 2010

[3] D S Misra J Pande and S M Das ldquoStudies on bacteriologicalquality of nainital lake water in different seasonsrdquo Water Airand Soil Pollution vol 19 no 2 pp 149ndash154 1983

[4] R Purohit and S P Singh ldquoSeasonal variation in physico-chemical limnology of shallow zones of Nainital Lake WesternHimalaya (India)rdquo Proceedings of the Indian National ScienceAcademy Section B Biological Sciences vol 47 no 2 pp 194ndash203 1981

[5] C K Jain D S Malik and R Yadav ldquoMetal fractionationstudy on bed sediments of Lake Nainital Uttaranchal IndiardquoEnvironmental Monitoring and Assessment vol 130 no 1ndash3 pp129ndash139 2007

[6] S Shah A Tewari and B Tewari ldquoImpact of human dis-turbance on forest vegetation and water resources of nainitalcatchmentrdquo Nature and Science vol 7 no 10 pp 74ndash78 2009

[7] S P Singh G Brij K K Vinish C Malavika U Manishaand B Mohan ldquoIntegrated management of water resources oflake nainital and its watershed an environmental economicsapproachrdquo inTheWorld BankAided ldquoIndia EnvironmentalMan-agement and Capacity Buildingrdquo Technical Assistance ProjectEERC Indira Gandhi Institute for Developmental ResearchMumbai India 2001-2002

[8] BIS Standards for Water for Drinking and Other Purposes BISNew Delhi India 2003

[9] ICMR ldquoManual of standards of quality for drinking watersuppliesrdquo ICMR New Delhi India 1975

[10] WHO Guidelines for Drinking Water Quality vol 1 of Recom-mendations WHO Geneva Switzerland 3rd edition 2004

[11] ldquoWater balance of lake Nainital Kumaun Himalayasrdquo UPNational Institute of Hydrology Roorkee 1ndash62 CS(AR)-698-99(1989ndash1999)

[12] American Public Health Association Standard Methods forExamination of Water and Waste Water American PublicHealth Association New York NY USA 1998

[13] R N Singhal Swaranjeet and R W Davies ldquoThe physico-chemical environment and the plankton of managed ponds inHaryana Indiardquo Proceedings of the Indian Academy of ScienceSection B vol 95 no 3 pp 353ndash363 1986

[14] A SreenivasanVK Pillai andT Franklin ldquoLimnological studyof a shallow water body (Kolovoi Lak) in Tamil Nadu IndiardquoJournal of Indian Hydrobiology vol 2 no 2 pp 61ndash69 1997

[15] ldquoWater quality studies of lake Nainital and surroundingsrdquo 1-127CS (AR)-1 National Institute ofHydrology Roorkee 19992000

[16] R K Trivedy P K Goel and C L Trisal Practical Methodsin Ecology and Environmental Science Environmental Publica-tions Karad India 1987

[17] J Schwartz C Angle and H Pitcher ldquoRelationship betweenchildhood blood lead levels and staturerdquo Pediatrics vol 77 no3 pp 281ndash288 1986

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Table 1 Drinking water quality standards units analytical method and recommending agencies (source [8ndash10])

Water quality Unit Analytical method Indian standards (desirable) andrecommended agencies

pH pH unit pH meter 65ndash85 (BISICMR)Turbidity NTU Turbidity meter 5 (BIS)Dissolved oxygen mgL DO meter 5 (ICMR)Electrical conductivity 120583scm Conductivity meter 300 (ICMR)Total dissolved solid mgL TDS meter 500 (BIS)Total suspended solid mgL Gravimetric 500 (WHO)

Temperature DegreeCelsius Portable thermometer mdash

Biochemical oxygendemand mgL Winkler azide method 5 (ICMR)

Total hardness CaCO3 mgL Titrimetric 300 (BISICMR)Total alkalinity CaCO3 mgL Titrimetric 120 (ICMR)Chloride mgL Argentometric 250 (BISICMR)Sodium mgL Flame photometer lt20 (WHO)Potassium mgL Flame photometer 10 (WHO)Phosphate MicrogramL UV spectrophotometer mdashLead mgL Atomic absorption 005 (BIS)Copper mgL Atomic absorption 005 (BIS)Iron mgL Atomic absorption 03 (BIS)Zinc mgL Atomic absorption 5 (BIS)BIS Bureau of Indian Standard WHO World Health Organization and ICMR Indian Council of Medical Research

basin) on the other hand is relatively less polluted Geology ofboth basins is one of the key interests for this studyThe lakersquosbasin is formed of folded and faulted rocks ofKrol andTal for-mation attributed to the Cambrian Age [11]The lake receiveswater from springs (Pardadhara andChunadhara) rainwaterand 22 inlet nullahs (9 are permanent which act as a majorconduit of polluted sludge and silt draining off into the lake)[1]The lake supports around 40000 local inhabitants presentin its catchment area hence anthropogenic activities likesurface runoff domestic sewage construction activities andagricultural activities have significantly changed the waterquality of the Nainital Lake

22 Sample Collection and Analysis Water samples werecollected from two sites of NainitalmdashMallital (L1) and Tallital(L2) (Figure 1) Fourteen grab samples were collected for eachmonth (January April July andOctober) from both the sitesIn order to collect representative samples a sampling stationnetwork was designed in such a way so as to cover wide rangeof factors such as drains and springs that influence the waterquality of the lake Water samples were collected in 2000mLpolyethylene sterilized bottles (cleaned with metal-free soapwashed with distilled water soaked in 10 nitric acid for24 hours and finally rinsed with ultrapure water) Watersamples were stored in an insulated ice-cooled containerand delivered to the laboratory on the same day All thesamples were kept at 4∘C to avoid physicochemical changesand interferenceThe sampling preservation transportation

Mallital (L1)

Tallital (L2)

Figure 1 Map showing the study area and surface water qualitysampling stations of Nainital Lake (source Google map)

and analysis of water samples were carried out accordingto the methods described in APHA-AWWA-WEF (1998)[12] The polyethylene bottles used for storing samples weresealed with tape to make the sample free from air contactSurface runoff domestic sewage and weathering of rockswere found to be responsible for influencing the physicaland chemical parameters of the Nainital Lake water A totalof 18 physicochemical parameters were analyzed in labo-ratory using standard protocol APHA-AWWA-WEF (1998)including total dissolved solids (TDS) total suspended solid(TSS) turbidity electrical conductivity (EC) phosphate totalhardness pH alkalinity temperature BOD DO Cl Na+ PbK Cu Fe and ZnWater quality parameters unit methods ofanalysis Indian standards and recommended agencies are allsummarized in Table 1





PO4




















1 Afforestation


2 Phytoremediation


3 Sediment basin






4 Conclusion






References






















Journal of












Volume 2014

Advances in









Geophysics


















PO4




















1 Afforestation


2 Phytoremediation


3 Sediment basin






4 Conclusion






References






















Journal of












Volume 2014

Advances in









Geophysics






















1 Afforestation


2 Phytoremediation


3 Sediment basin






4 Conclusion






References






















Journal of












Volume 2014

Advances in









Geophysics


















References






















Journal of












Volume 2014

Advances in









Geophysics


















Journal of












Volume 2014

Advances in









Geophysics














research article water quality assessment of the central...

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