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STUDIES ON THE PHYSICO-CHEMICAL PARAMETERS AND THEIRSEASONAL VARIATIONS IN WATER AT SELECTED SITES OF NEYYARRIVER, KERALA- INDIA

Journal of Aquatic Biology and Fisheries Vol. 2/No. 2/2014/pp. 1 to 6

Ajesh, G1*., Aneesh, M.S1., Meera George1., Jithu Krishnan, U1.,Lekshmi, N.R2. and Jithine, J.R2.1Department of Zoology, Mar Ivanios College, Thiruvananthapuram, Kerala2Central Tuber Crop Research Institute, Sreekaryam, Thiruvananthapuram, Kerala, India*Email: Joyajesh87@gmail.com

Abstract: The ‘Neyyar’ river is the southernmost river in Kerala. The river water is polluted mainly due toanthropogenic sources, domestic effluents, Hospital Sewage, hotel waste discharges and sand mining. Thispolluted water is used for drinking purpose in some areas especially coastal areas and for irrigational purpose.A proper monitoring is required and this work will help to get an idea about the present status and in the futureevaluation studies. The work underlines the water quality through the assessment of sub parameters like pH,Dissolved Oxygen (DO), Biological Oxygen Demand (BOD), Nitrate Nitrogen Content (NO2-N), PhosphatePhosphorus Content (PO4-P), Total Dissolved Solids (TDS), Turbidity and MPN Coliform Count. Based on theseparameters, Water Quality Indexing (WQI) of the selected water bodies had been undertaken to facilitate aconvenient single value mathematical means for assessment as well as comparison as per the criteria prescribedby National Sanitation Foundation. Present study covers the seasonal deflection (Pre-monsoon and Post-monsoon)in pollution load and site/position variation to the respective. In selected four zones starting from origin to theend, signif icant variations in parameters were observed.

Key words: Neyyar river, Water quality, Coliform count

Received on: 10 October 2013, accepted on: 12 December 2013

INTRODUCTION

Water is the most common substance on earthand it is omnipresent. It is the most abundantconstituent of any organism and life isconsidered to have evolved from water. Wateras rain continuously erodes the land, washingthe soil into rivers. Rivers cut through rocks,carve canyons, and buildup land at thebarmouths. A river is a natural water resourceflows towards an ocean, a lake, a sea or anotherriver. In a few cases a river simply flows into theground or dries up completely before reachinganother body of water. Small rivers may be alsocalled by several other names including stream,creek, brook, tributary and rill, there is nogeneral rule that def ines what can be called ariver, although in some countries orcommunities a stream may be def ined by size.

In India, the state of Kerala has 44 rivers, 29fresh water lakes and perennial springs and thehighest well density in the world (250 open

wells/Km2). In Kerala, at present, there are aboutone hundred and twenty schemes in operationfor providing drinking water to the rural andurban areas of Thiruvananthapuram District.Seventy one rural water supply schemes andtwelve urban water supply schemes are underimplementation. Disruption of water supplyhappens on a regular basis due to reasons suchas bursting of main pipelines, mechanicalproblems, contamination f rom garbagetreatment plants etc. (The Hindu – May 19, 2005;Monday, Jun 06, 2005).

Neyyar River is the southern-most river of theKerala state. The river water is polluted mainlydue to anthropogenic sources, domesticeff luents, Hospital Sewage, hotel wastedischarges and sand mining. This pollutedwater is used for drinking purpose in some areasespecially coastal areas and for irrigationalpurpose. So a proper monitoring is required and

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this work will help to get an idea about thecurrent status and in the future evaluationstudies.. The study also helps to evaluate theseasonal changes of physico-chemicalparameters of river water.

MATERIALS AND METHODS

Study area

Neyyar originates from the Agasthyarkudamhills, flows through Neyyatinkara taluk and joinsLakshadweep Sea near Poovar. It has a totallength of 56.Km. The main tributaries are Kallarand Karavaliyar. Streams like Vandichitrathode,Kulathoor Valiyathode, Maruthoorthode,Athiyannoorthide, Thaliyalthode, Kottukala-thode and Venganoorthode joins the mainstream. There is an irrigation project constru-cted in 1973 at Kallikkadu near Kattakkada,which is about 29Km from Trivandrum city.Neyyar wildlife sanctuary in this basin is afamous tourist place. Four areas were randomlyidentif ied for present investigation.

Site No. 1: (S1)

Site No. 1 selected for present study belongs toKallikkadu near Kattakkada. Neyyar dam issituated in this panchayath. The dam has only32Km east of Thiruvananthapuram. The peakAgasthyarkudam is a lovely spot, very close toNeyyar dam. The area around this river is freefrom any kind of pollution. This area is rich withf ish, fauna and planktons.

Site No.2: (S2)

Site No. 2 selected for present study belongs toAruvippuram near Aruvippuram Siva Temple.Aruvippuram is a village in the Southern districtof Thiruvananthapuram in Kerala. It is a famoustemple established by Sree Narayana Guru in1888. Activities like bathing, washing and sandmining are the major environmental problems.

Site No. 3: (S3)

Site No. 3 selected for present study belongs toNeyyattinkara near the banks of Neyyar River.Neyyattinkara and neighboring areas has manycottage industries and handloom. TheBalaramapuram handloom industry isworldwide for its f ine hosiery. The nameNeyyattinkara in Malayalam literary means theShore of Neyyar River. Neyyatinkara Taluk

Hospital is located a few distances away fromthe river. The waste water from the hospital isdirectly discharged into the river. This creates amajor course of water pollution in this area.

Site No. 4: (S4)

Site No. 4 selected for present study belongs toPoovar Pozhikkara near Poovar. Poovar is asmall coastal village in the Trivandrum district.The village is almost at the southern tip ofTrivandrum and there is only one last villagePozhiyoor which mark the end of Kerala. Poovarlies close to Vizhinjam, a natural harbor. Poovarhas an estuary which connects the sea duringhigh tides. This area is a waste dumping sitefrom tourist places and fecal contaminationfrom thickly populated coastal place is anotherproblem in this area.

Sample collection

Water samples were collected from the studyareas selected during summer season (pre-monsoon), April and the rainy season(monsoon), June of 2011, in acid-cleaned, non-reactive plastic containers. Temperature and pHvalue were measured in the f ield using sensitivethermometer and portable pH meter. Waterquality parameters were analyzed following thestandard procedures prescribed by APHA (1993),Grasshoff (1983) and Trivedy and Goel (1986).Water quality indexing was performed followingthe protocol devised by the NSF (NationalSanitation Foundation), USA (NSF, 2004).

Biochemical Analysis

Dissolved Oxygen (DO)

DO was determined using the Winkler ’smethod (Michael, 1984) and using the formula.

DO in (mg/litre) =

Where, k = vol. of bottle

Vol. of bottle - volume of reagent added

SampleofVol.0.689 xOSNaofVol. x200 xk 322

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Biological Oxygen Demand (BOD)

The standard procedure about BOD prescribedby APHA was followed to f ind out the BOD.The BOD levels 1-2 mg/l is considered as verygood, levels 3-5 mg/l fair 3-9 mg/l poor and 100mg/l or greater very poor. (APHA, 1992).

Calculate BOD’s as follows.

BOD, mg/l =

Where D1 = DO of diluted sample immediatelyafter precipitation.

D2 = DO of sample after 5 d incubation at 20Cmg/l

P = Decimal volumetric fraction of sample used

Nitrogen NO2 (Nitrite)

Nitrite (NO2-) is determined through formation

of a reddish purple azodye produced at pH 2.0to 2.5 by coupling diazotized sulfanilamide withN-(1-napthyl)-ethylendiamine dihydrochloride(NED-dihydrochloride) (US EnvironmentalProtection Agency 1979)

Phosphate phosphorous(By Ascorbic acid method): Ammoniummolybdate and Potassium antimonyl tartatereact in acid medium with orthophosphate toform phosphomolybdic acid that is reduced tointensely colored molybdenum blue by ascorbicacid (Murphy, 1962).

Mg P/L =

Total Dissolved Solids (TDS)

“Total Solids” is the term applied to the materialresidue left in the vessel after evaporation of asample and its subsequent drying in an oven ata def ined temperature. Total solids include “totalsuspended solids” the portion of total solidsretained by a f ilter and total dissolved solids theportion that passes through the f ilter.

A well mixed sample is evaporated in a weigheddish and dried to a constant weight in an ovenat 103 – 105C. the increase in weight over that

PD2D1

of empty dish represents the total solids. (USEnvironmental protection Agency, 1979)

Mg total solids/L =

Where; A = Weight of dried residue + dish mgand

B = Weight of dish

Turbidity

Turbidity in water is caused by suspended adcolloidal matter such as clay, slit, f inely dividedorganic and inorganic matter, planktons andother microscopic organisms. Turbidity is theexpression of the optical property that causeslight to be scattered and absorbed rather thantransmitted with no change in direction or fluxlevel through the sample.

This method is based on a comparison of theintensity of the light scattered by the sampleunder def ined conditions with the intensity ofthe light scattered by a standard referencesuspension under the same conditions. Thehigher the intensity of scattered light, the higherturbidity. Formazin polymer is used as theprimary standard reference suspension.

Nephelo Metric Method. (US EnvironmentalProtection Agency, 1993)

MPN coliform content

The Coliform group consists of several generaof bacteria belonging to the familyEnterobacteriacca. The standard test for thecoliform group may be carried out by multipletube fermentation technique and procedurethrough the presumptive and conf irmedphases. (U.S Environmental ProtectionAgency, 1989)

DISCUSSION

Scarcity of portable water is increasinglyassuming alarming dimensions in Kerala,especially in Thiruvananthapuram district.The water supply schemes implementedhere are totally inadequate to cater for theburgeoning demands for the over expandingtownship and housing schemes. Major rivers in

volume/mlSample x1000B)-(A

sampleofml x1000Pmg

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Thiruvananthapuram district are Neyyar river(56 Km), southern-most river in Kerala state andKaramana River (67 Km). the river water isbenef icent for industrial, agricultural, irrigationand drinking water purposes. These water bodiesare polluted mainly due to pollutants fromanthropogenic origin. Investigations of presentkind would provide valuable base-line dataabout the status of pollution from the origin tothe end of Neyyar River.

The present investigation involved the evaluationof nine water quality parameters in selectedregions of Neyyar River.

It was observed that in Neyyar River the watertemperature at Site No.1 in April and June werethe same. In Site No.2 and Site No.3, slightincrease in temperature as compared to f irst sitewas observed. In Site No.4, higher watertemperature was observed due to increasedoxidation of organic pollutants discharged towater from coastal areas (Table 1).

In the case of pH, during April, it is slight acidicin nature at four different locations except SiteNo.1. In June, the acidity was found to increaseslightly. This may be due to the addition ofsurface run off with lower pH during themonsoon pH of water at Site No.1 in April andJune were the same. In Site No.3 and Site No.4showed higher acidity in the two seasons ascompared to Site No.1 due to increased acidicpollutants in these areas (Table 1).

Dissolved Oxygen is a good indicator of generalhealth of an aquatic system. It is also related tothe productivity of aquatic systems. It is alsorelated to the productivity of aquatic systems.During the period of study, dissolved oxygenincreased in monsoon season due to moredissolution of atmospheric O2 in water and dueto increased movement of river water in rainyseason. DO content in water was higher in SiteNo.1 in the two seasons. At Site No.2 and SiteNo.3, the DO value slightly decreased. Site No.4showed very low DO as compared to the otherthree sites. This low DO was due to the increasedaccumulation of organic matter from coastalareas and effluents from hotels (Table 1).

BOD is a test used to measure the influence ofbio-degradable organic matter present in samplesof water. (Agarwal et al., 1976; Badge and Verma,

1991). BOD serves as an indication of amount oforganic load as well as occurrence of inorganicmaterials such as Sulphides and Ferrous ions(APHA, 1992). The BOD value of present studywere higher in April as compared to June exceptSite No.1. At Site No.1, water pollution is low andthe present result is BDL (Below DetectableLimit). At Site No.2, the values were in safe rangebelow 3 mg/L recommended by ICMR (1975) andISI (1991) and the International Standards of 5and 6 mg/L by USPH and WHO respectively (De,1999). At Site No.3 and Site No.4, the values werehigher than 3mg/L. The higher BOD may beattributed to the accumulation of dead organicmatter into the river, higher degree of waterpollution (Table 1).

Values of NO2-N detected in present studyremain lower than accepted drinking waterstandards (20mg/L – ICMR, 1975, 45mg/L – ISI,1991). Nitrite level in water increased during rainyseason. In pre-monsoon, the nitrite values werelower as compared to monsoon because absenceof rain-fall, increase in temperature, reduceddrainage. The result of present study agrees withthe report of Paul and Verma (1999) (Table 1).

Phosphorous in natural water is present in theform of H2PO4

-1, HPO4-2 and PO4

-3 and also inassociation with organic materials (Liss, 1976,Trivedy and Goel, 1986). The major sources ofPO4-P in aquatic systems are domestic sewage,agricultural effluents containing fertilizers andindustrial eff luents. Higher concentration ofphosphates can be linked to higher degree ofpollution (Desai, 1995). The values of PO4-Pfound in present study remained considerablylower as compared to the prescribed level ofUSPH standard 0.1 mg/L. In April, the values atfour different locations were BDL(BelowDetectable Limit). In June, the slight increasesin the level due to the presence of rain-fall,increased drainage and decrease in temperature(Table 1).

TDS originates from natural sources such as rainand bottom deposits as well as in flowing water.The TDS value of present investigation at f irstthree sites less than 100 mg/L. At Site No.4, thevalue more than 500 mg/L. The EPA secondaryregulations advice a maximum contamination500 mg/L for TDS (http://www.epa.gov/safewater/mcl.html). When TDS level go beyond

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TABLE 1. Variations in Physico- chemical parameters and their seasonal variations in water atselected sites of Neyyar River during April to June 2011. Observations and SD are given. (Ob:observed; SD: Standard Deviation; BDL: Below detectable level)

500 mg/L, it is generally regarded unf it forhuman consumption. In present study, slightincrease of TDS value in June at the four sites ascompared to May due to the precipitation in theform of rain-water. Precipitation in the form ofrain-water contains as much as 30 mg/L to40mg/L of solids. The values of presentinvestigation were very low as per acceptedstandards except the Site No. 4 (Table 1).

Turbidity is considered as good indicator ofwater quality. The WHO establishes the turbidityof drinking water should not be more than 5NTU and should ideally below 1 NTU. Theturbidity of water increases in monsoon ascompared to pre-monsoon due to seasonalf luctuation, increased drainage f romsurrounding areas. At Site No. 1, the TDS valuesin April and June are less than 5 NTU. At Site

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No.2, the value is less than 5 NTU in April andmore than 5 NTU in June. At Site No.3, Site No.4,the values were more than 5 NTU in pre-monsoon and monsoon. This excessive turbiditymay due to the presence of heavy metal ions,pesticides or water-borne disease causingorganisms may attach to the suspendedparticles.

The MPN coliform test is used to detect andcalculate coliformpopulation in water samples.CPCB has prescribed an MPN count of 50 orless than 50 as accepted standard for potatbilitywithout conventional treatment. The valuesrecorded during the present investigation showa signif icant decrease in monsoon as comparedto pre-monsoon. At Site No.1, the values were<50 in April and June. At Site No.2, Site No.3and Site No.4, the values were >50 recorded inApril and June. The higher values may be dueto increased incidence of seepage of domesticeff luents from septic tanks and drainage fromother anthropogenic sources.

The state of Kerala, best owed with a large numberof river-water resources that can serve as principalcomponents of an excellent water-harvestingmechanism. Scarcity of drinking water is a matterof serious concern in Thiruvananthapuramdistrict. The water supply schemes are increasinglybecoming very inadequate to cater for the ever-increasing demands for water. In this context, it ishighly essential to have suff icient data on the

status of existing resources. Hence, the presentinvestigation evaluate water quality status of NeyyarRiver at four different areas and in two differentseasons, investigation of present kind are boundto provide water quality of the river

ACKNOWLEDGEMENTS

We acknowledge the physical support f romResearch Department of Zoology, Mar IvaniosCollege, Thiruvananthapuram (University ofKerala) and Division of Crop Protection, CentralTuber Crop Research Institute, Thiruvanan-thapuram (ICAR, Government of India)

REFERENCES

APHA (American Public Health Association).1992. Standard methods for the examinationof water and waste water, 18th edn., APHA –AWWA – WPCF, 1134 pp.

Murphy. 1962. A modif ied single solution of thedetermination of phosphate in natural waters.

NSF International. 2004. National SanitationFoundation International, USA. http://www.nsf.org

Michael, P. 1984. Ecological methods for f ieldand laboratory investigation, 105– 111

The Hindu – May 19, 2005; Monday, Jun 06, 2005Winkler, L.W. 1888. Die Bestimmung des im

Wasser gelosten Sauerstoffen. Ber. Dtsche.Chem. Ges., 21: 2843– 2855