Nilwala River Research Articles

Geospatial assessment of a severe flood event in the Nilwala River basin, Sri Lanka

Geospatial assessment of a severe flood event in the Nilwala River basin, Sri Lanka

Impact of rainfall on the water quality of a tropical river: based on the Nilwala River in the southern province of Sri Lanka between March and October 2019

ABSTRACT The study addresses the pressing need for an effective monitoring system to assess aquatic water quality, given the exacerbating impact of climate change on surface water bodies. Focusing on the Nilwala River, the research pursues three main objectives: comparative analysis of the Weighted Arithmetic Water Quality Index (WAWQI) values across different river locations, exploration of correlations between monthly rainfall and various physicochemical parameters at distinct sampling sites, and examination of notable disparities in the WAWQI between dry and wet months. Data collected from eight river locations from March to October 2019 revealed significant temporal variations in pH, temperature, chemical oxygen demand (COD), electrical conductivity (EC), alkalinity, chloride (Cl−), and nitrate (NO3-) content. The WAWQI increased across all sites during the drought, with only Site 4 (Wellathota) deemed suitable for drinking. Statistical analyses using an one-way ANOVA and multiple linear regressions unveiled significant relationships between rainfall and pH, biological oxygen demand (BOD), EC, and total alkalinity. The total alkalinity is the most affected parameter by the rainfall. Rainfall positively predicted BOD, COD, and NO3- concentration while negatively predicting other parameters.

Temporal Variation of Water Quality in Nilwala River, Southern Province, Sri Lanka

This study intended to investigate the temporal variation of water quality of the Nilwala river in the Matara district and to determine how the changes in rainfall affect to river water quality. Water samples were collected monthly from March 2019 to October 2019 (considering the second Inter monsoon season and first inter-monsoon season) at eight locations along the main river. Water quality parameters such as chemical oxygen demand (COD), biological oxygen demand (BOD), pH, electrical conductivity, temperature, alkalinity, hardness, chloride, nitrate and phosphate were analyzed using APHA 23rd edition of standard methods for the examination of water and wastewater. Experimental results were statistically analyzed by Two-way ANOVA using Minitab 17. The pH, EC, temperature, alkalinity and nitrate concentration showed statistically significant differences among the months (p<0.001) and those showed statistically significant differences with monthly rainfall (p< 0.001). There is a statistically significant relationship between rainfall and month (p<0.001). There is a statistically significant relationship between rainfall and sampling location (p<0.001). The highest rainfall was recorded from august to November (2nd inter-monsoon season) and secondly from March to May (1st inter-monsoon season) was recorded. Conductivity, pH and temperature were decreased from March to June. This may due to 1st inter monsoon rainfall. Conductivity was increased during august-november. Flooding can increase conductivity when it washes salts and minerals from the soil into the water. Nitrate concentration in the majority of the locations was increased during march-may. Total alkalinity, pH and nitrate were increased from august to November. The temperature of river water at all locations decreased from august- November. In conclusion, the pH, EC, temperature, alkalinity and nitrate concentration showed statistically significant differences among each month. It may due to variation of rainfall. Upper part of Nilwala River had a higher rainfall than lower basin.
 Keywords: Conductivity, Nilwala River, pH, temporal variation, Water quality

The Influence of Preconsolidation Pressure on Undrained Shear Strength Characteristics of Peaty Clay in Sri Lanka

This research study investigated the effect of preconsolidation pressure on the shear strength parameters of very soft peaty clay based on a series of laboratory tests. The study included 15 Consolidated Undrained (CU) triaxial tests on peaty clay extracted from the Nilwala river basin, with preconsolidation pressures ranging from 0 to 100 kPa in 20 kPa intervals and cell pressures of 50, 100 and 150 kPa. The results indicated that the peak deviator stress of peaty clay decreased with increasing preconsolidation pressure, indicating decrease in its shear strength parameters with preconsolidation pressure. It was observed that peaty clay is highly sensitive to disturbance and requires sufficient time to regain its shear strength once its natural microstructure is altered. The study has significant implications for the construction of embankments on soft soils, particularly peaty clays. It highlights the need for accurate estimation of the undrained shear strength parameters of peaty clay, considering soil composition, structure and type of loading. It also emphasizes the importance of minimizing disturbance during construction activities to avoid compromising the stability of embankments.

A Critical Evaluation of Streamflow Estimation of an Ungauged Watershed using a Gauged Watershed of Same River Basin – Case of Nilwala River Basin

Transferring hydrological model parameters of a nearby gauged watershed to an ungauged watershed is being widely practiced to predict streamflow in the ungauged watershed. However, proper conclusions on transferring data from the main to sub-watershed and vice versa need to be established, then only watershed managers can plan where to locate or ensure optimum use of resources when establishing gauging stations. Therefore, the present study aimed to evaluate the performance of spatial transferability by using the Tank Model, which was initially calibrated to daily streamflow from water year 2008/09 to 2017/18 observed at two gauged watersheds in Nilwala River Basin, and then transferred from main to sub-watershed and vice versa. The efficiency of predictions under two parameter transferability scenarios was highly acceptable where the Mean Ratio of Absolute Error (MRAE) values were 0.35-0.39 and, the accuracy of annual water balance was 91.8%-93.3%. Most importantly, the best results were in the intermediate flow regime with an accuracy of 61%-70%. The monthly-scaled streamflow indicated an accuracy of 83%-92%. The present study demonstrated the liability of the Tank Model for successful estimation of daily streamflow with an average accuracy of 63% under spatial parameter transferability thereby with only a single wellmanaged streamflow gauging station, Tank Model can be applied for sustainable water resources management in similar ungauged watersheds of the basin.

Amelioration of acid sulphate soils in Nilwala river basin

Paddy tracts of Nilwala basin has been affected by the implementation of Nilwala Flood Protection and Drainage Project in 1979 due to excessive drainage, and nearly 7000 acres of land is abandoned. The water table goes down to the level of 50 cm below soil surface during dry periods and soil pH falls to 3-4 causing acid sulphate condition. Hitherto several efforts have been made to ameliorate the paddy lands but no any economical solution is obtained. The National Science Foundation project to find out the feasibility of using natural hydraulic forces to increase water table to keep the acid sulphate forming minerals at bay and to cultivate rice in these paddy lands. Water table fluctuation in relation to water level in the drainage channel was studied over one year and there was found a very high correlation (r2=0.985) indicating a possibility of increasing water table by heading up water in the channel. Simulated pot experiment showed that increasing water table to 15 cm below soil surface allows rice to grow effectively, showing plant survival of 112 (53%) compared to 28 (15%) plants in control. Recorded plant height of Bg. 357 variety was 35 cm compared to 22 cm in different treatments and control, respectively. Soil pH also increased to a value closer to 6.0 in the treatment which is conducive for rice cultivation. However, the low values of plant survival and plant heights were due to unusual extreme low rainfall in 2020/21 Maha season compared to 10 years’ average. SAARC J. Agric., 20(2): 211-221 (2022)

Trends and Variabilities in Rainfall and Streamflow: A Case Study of the Nilwala River Basin in Sri Lanka

Rainfall is one of the dominating climatic parameters that affect water availability. Trend analysis is of paramount significance to understand the behavior of hydrological and climatic variables over a long timescale. The main aim of the present study was to identify trends and analyze existing linkages between rainfall and streamflow in the Nilwala River Basin (NRB) of Southern Sri Lanka. An investigation of the trends, detection of change points and streamflow alteration, and linkage between rainfall and streamflow were carried out using the Mann–Kendall test, Sen’s slope test, Pettitt’s test, indicators of hydrological alteration (IHA), and Pearson’s correlation test. Selected rainfall-related extreme climatic indices, namely, CDD, CWD, PRCPTOT, R25, and Rx5, were calculated using the RClimdex software. Trend analysis of rainfall data and extreme rainfall indices demonstrated few statistically significant trends at the monthly, seasonal, and annual scales, while streamflow data showed non-significant trends, except for December. Pettitt’s test showed that Dampahala had a higher number of statistically significant change points among the six rainfall stations. The Pearson coefficient correlation showed a strong-to–very-strong positive relationship between rainfall and streamflow. Generally, both rainfall and streamflow showed non-significant trend patterns in the NRB, suggesting that rainfall had a higher impact on streamflow patterns in the basin. The historical trends of extreme climatic indices suggested that the NRB did not experience extreme climates. The results of the present study will provide valuable information for water resource planning, flood and disaster mitigation, agricultural operations planning, and hydropower generation in the NRB.

Application of GIS and Logistic Regression for Flood Susceptibility Mapping in Nilwala River Basin, Sri Lanka

"ENGINEER", established in 1973 by The Institution of Engineers, is a Journal for dissemination of Engineering knowledge, published quarterly.If you are interested in contributing an Original Technical Paper based on research by the author(s) (intended for Section I) or an Original Article of Professional or Technical interest related to Engineering. (Section II) to this journal please go through the publication checklist which can be downloaded from here.Cover DescriptionCover images show a few views of the Maduru Oya reservoir and construction of right bank canal. The Institution of Engineers, Sri Lanka, acknowledges Eng. L.D. Amila Sanjeewa of the Department of Irrigation for providing images and related information of the project.

Hydrological Modelling with the Tank Model for Water Resource Management of Nilwala River Basin

"ENGINEER", established in 1973 by The Institution of Engineers, is a Journal for dissemination of Engineering knowledge, published quarterly.If you are interested in contributing an Original Technical Paper based on research by the author(s) (intended for Section I) or an Original Article of Professional or Technical interest related to Engineering. (Section II) to this journal please go through the publication checklist which can be downloaded from here.Cover DescriptionCover images show views of the Giant tank and the Tekkama anicut.

Prioritization of Sub-basins of Nilwala River Basin for Flood Exposure using Multi Criteria Decision Analysis

"ENGINEER", established in 1973 by The Institution of Engineers, is a Journal for dissemination of Engineering knowledge, published quarterly.If you are interested in contributing an Original Technical Paper based on research by the author(s) (intended for Section I) or an Original Article of Professional or Technical interest related to Engineering. (Section II) to this journal please go through the publication checklist which can be downloaded from here.Cover DescriptionCover images show views of the Giant tank and the Tekkama anicut.

Evaluation of Future Streamflow in the Upper Part of the Nilwala River Basin (Sri Lanka) under Climate Change

Climate change is a serious and complex crisis that impacts humankind in different ways. It affects the availability of water resources, especially in the tropical regions of South Asia to a greater extent. However, the impact of climate change on water resources in Sri Lanka has been the least explored. Noteworthy, this is the first study in Sri Lanka that attempts to evaluate the impact of climate change in streamflow in a watershed located in the southern coastal belt of the island. The objective of this paper is to evaluate the climate change impact on streamflow of the Upper Nilwala River Basin (UNRB), Sri Lanka. In this study, the bias-corrected rainfall data from three Regional Climate Models (RCMs) under two Representative Concentration Pathways (RCPs): RCP4.5 and RCP8.5 were fed into the Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) model to obtain future streamflow. Bias correction of future rainfall data in the Nilwala River Basin (NRB) was conducted using the Linear Scaling Method (LSM). Future precipitation was projected under three timelines: 2020s (2021–2047), 2050s (2048–2073), and 2080s (2074–2099) and was compared against the baseline period from 1980 to 2020. The ensemble mean annual precipitation in the NRB is expected to rise by 3.63%, 16.49%, and 12.82% under the RCP 4.5 emission scenario during the 2020s, 2050s, and 2080s, and 4.26%, 8.94%, and 18.04% under RCP 8.5 emission scenario during 2020s, 2050s and 2080s, respectively. The future annual streamflow of the UNRB is projected to increase by 59.30% and 65.79% under the ensemble RCP4.5 and RCP8.5 climate scenarios, respectively, when compared to the baseline scenario. In addition, the seasonal flows are also expected to increase for both RCPs for all seasons with an exception during the southwest monsoon season in the 2015–2042 period under the RCP4.5 emission scenario. In general, the results of the present study demonstrate that climate and streamflow of the NRB are expected to experience changes when compared to current climatic conditions. The results of the present study will be of major importance for river basin planners and government agencies to develop sustainable water management strategies and adaptation options to offset the negative impacts of future changes in climate.

Towards Coupling of 1D and 2D Models for Flood Simulation—A Case Study of Nilwala River Basin, Sri Lanka

The Nilwala river basin is prone to frequent flooding during the southwest monsoon and second intermonsoon periods. Several studies have recommended coupling 1D and 2D models for flood modelling as they provide sufficient descriptive information of floodplains with greater computational efficiency. This study aims to couple a 1D hydrological model (HEC-HMS) with a 2D hydraulic model (iRIC) to simulate flooding in the Nilwala river basin. Hourly rainfall and streamflow data of three flood events were used for calibration and validation of HEC-HMS. The model performed exceptionally well considering the Nash–Sutcliffe coefficient, percent bias, and root mean square error. The flood event of May 2017 was simulated on iRIC using the streamflow hydrographs modelled by HEC-HMS. An overall accuracy of 81.5% was attained when the simulated extent was compared with the surveyed flood extent. The accuracy of the simulated flood depth was assessed using the observed water level at Tudawa gauging station, which yielded an NSE of 0.94, PBIAS of −4.28, RMSE of 0.18 and R2 of 0.95. Thus, the coupled model provided an accurate estimate of the flood extent and depth and can be further developed for hydrological flood forecasting on a regional scale.

Mitigating the Human-Crocodile Conflict in Sri Lanka: A Study Based on the Nilwala River Area in Matara District

Human and crocodile have been coexisting for many years in Sri Lanka, particularly close to the Nilwala river area in Matara District, but fatalities were rarely reported. However, during the last decade the threats from crocodiles to humans have enhanced in the Nilwala river area, mainly during the years of 2005, 2008, 2009, 2012, 2013, 2014 and 2015. Some 26 attacks, killing 18 humans by saltwater crocodiles were recorded since 2000 in this area. In retaliation to these attacks, people in this area killed several crocodiles, and recorded the saltwater crocodile under the threatened category in Sri Lanka. Therefore, it is a worth to form a dialogue to mitigate human-crocodile conflict in the Nilwala river area in Sri Lanka. The Study was mainly based on primary and secondary data. Primary data was collected from semi-structured interviews. Sample size was consisted of forty-five (45) respondents. Secondary data was collected through published books, research reports, symposia proceedings, journal articles and web sites etc. Collected data from different sources, as mentioned above was analyzed using qualitative and quantitative methods, and it was presented using maps, texts, tables and figures. The study found that sand mining, population rise, using the river for daily needs such as drinking, bathing, washing clothes and fishing, unauthorized buildings in the river bank, scrub jungles, slow flowing of river are the major causes of the human-crocodile conflict in Nilwala river area. The study further found that Piladuwa, Fort and Thihagoda are the most vulnerable areas for human-crocodile conflict. "Kimbulkotuwa" or Crocodile Excluding Enclosure (CEEs) is a main method used to mitigate the human-crocodile conflict in this area.

Determination of Grey Water Footprint of Rice Cultivation in the Right Bank of Nilwala Downstream

Excess nutrients released through leaching and/or runoff from agricultural lands into natural water bodies has caused water pollution all over the world. Water pollution by means of discharging chemical substances from paddy fields to water bodies has become a critical problem in Sri Lanka. The grey water footprint is considered as a rough estimate of water pollution associated with a particular activity. The grey water footprint associated with the paddy cultivation in the right bank of Nilwala” downstream was calculated based on two levels of fertilizer applications; level 1: fertilization according to the recommendations of the Department of Agriculture, Sri Lanka and level 2: fertilization based on farmer's preferences. Sampling was performed once a day for a week after each fertilization. Nitrate concentration of water samples was analyzed through Ultraviolet Spectrometric Screening method while pH and electrical conductivity were measured using pH meter and conductivity meter, respectively. Daily rainfall over the study area was recorded throughout the study period. The grey water footprint calculated based on the nitrate discharge for fertilization level 1 and level 2 were 0.93 m3/ha and 2.26 m3/ha respectively. As it is analyzed by the one-sample t-tests, the nitrate concentrations, pH and electrical conductivity of paddy water are significantly lower than that of proposed ambient water quality standards for Sri Lanka. As revealed by two-sample t-tests, nitrate concentrations, pH and electrical conductivity of water samples were significantly different from each other with respect to the both levels of fertilization. However, the nitrate concentrations and electrical conductivity values of water samples related to both levels of fertilization and pH values related to fertilization level 1, were significantly higher than that of raw water in Nilwala river which is used for irrigation, while pH values related to fertilization level 2 were significantly lower than the same. Keywords: Grey water footprint, Paddy cultivation, Nitrate, pH, Electrical conductivity

Water quality of Nilwala River, Sri Lanka in relation to land use practices

The Nilwala River is the third largest in the southern province of Sri Lanka which runs through 72 km along its cause. Conversion of forest lands to agricultural lands, expansion of urban areas and clearing of land for construction purposes in the catchment are major issues affecting water quality in Nilwala River. The water quality of the Nilwala River lower basin at 16 locations was estimated for 4 months from September2010 to December 2010 in two-week intervals. Water quality parameters pH, Electrical conductivity(EC), Dissolved oxygen (DO), Biochemical Oxygen demand (BOD5), turbidity, colour, Total Dissolved Solids (TDS), total hardness, alkalinity, Nitrite-N (NO2--N), Nitrate -N (NO3--N), Phosphate (PO43- -P), Sulphate (SO43-), Total Fe, Ca2+, F- and Cl- were evaluated in the sampling locations. The spatial and temporal variation of water quality associated with different land use categories were analyzed using Two-way ANOVA. Principal Component Analysis (PCA) and Cluster Analysis (CA) were also conducted to determine the association between water quality variation and land use impacts of the catchment. A significant (p <0.05) spatial variation of water quality parameters, except the hardness, Fluoride and Ca+2among sites were observed to be associated with different land use categories. No significant (p >0.05) temporal variability in water quality parameters except Nitrite and hardness was detected. PCA and CA also indicated a strong association between the water quality variables and the land use types of the river basin. Urban impacts, land clearance in the catchment and sand mining activities of the river bed were found to be the most significant impacts to the water quality of the river and areas with forest cover having positive impact to the water quality. These findings emphasize the need of better catchment management approaches and remediation of urban impacts on river water quality.

Application of DSSAT Crop Simulation Model to Identify the Changes of Rice Growth and Yield in Nilwala River Basin for Mid-centuries under Changing Climatic Conditions

Changes of climate will be one of the deciding factors that affect for future food production in the world because crop growth is highly sensitive to any changes of climatic conditions. As the rice is staple food of Sri Lankans, it is essential to identify the impacts of climate changes on country's rice production. This study was conducted to identify the yield and growth changes of most popular two rice varieties (At362 and Bg357) cultivated in Nilwala river basin at Yala season under the global climate change scenario Representative Concentrate Pathway (RCP) 8.5. The Decision Support System for Agro technology Transfer (DSSAT) software is used to forecast the rice yield for Yala season in mid-centuries. To simulate the rice yield DSSAT requires data sets of crop growth and management, daily weather data and soil data. Crop management data were obtained from an experiment which was conducted in Palatuwa area at Nilwala downstream in Matara district. Daily weather data were collected from Mapalana weather station and soil data were collected from wet zone soil classification. Model was calibrated using experimental data for Yala season 2014 and model was validated using collected data in Yala season 2013. Future yield was predicted using forecasted weather data under climate change scenario RCP 8.5 for Mapalana area. The results show that increasing temperature and solar radiation and decreasing rainfall in mid-centuries affects both yield and growth of rice. Grain yield in mid-centuries shows decreasing trend in both varieties by 25% to 35% than the yield at 2014 and growth period will be shorter than the present conditions.

Growth of Acropora formosa Fragments in In-situ Coral Nurseries at Polhena Reef, Matara, Sri Lanka

Coral reef are one of the most valuable coastal ecosystems, yet they are under various threats. Present study was to investigate the growth of Acropora Formosa fragments in in-situ coral nurseries of Matara Pollhena reef located on the southern coast of Sri Lanka. Study was conducted between April to November 2014. Eight different sites representing open sea and reef lagoon were selected to compare growth of A. formosa fragments in coral nurseries. Seawater quality parameters such as salinity, water temperature, pH, dissolved oxygen, nitrates, and phosphates were measured in monthly intervals. In addition, sedimentation rate was determined by deploying sediment traps. The highest mean extension growth rate for A. formosa (1.07±0.05 cm per month) was recorded at a site in the reef lagoon close to Nilwala river out fall and lowest mean extension rate (0.20±0.06 cm per month) was also recorded in reef lagoon more southward to the Nilwala river outfall. There was significantly different growth rates among eight sampling sites (t-test, p<0.05). The mean extension growth rates for open sea sites were higher when compared with reef lagoon sites (0.41±0.09 cm per month, 0.72±0.07 cm per month) respectively. The survival rates of coral fragments were ranged from 85.71% to 65.08%. The results highlight that the A. formosa shows differential growth rates in reef lagoon and open sea areas. Further, A. formosa has higher growth rate compared to other coral species and also can withstand higher sedimentation rates. Keywords: Acropora formosa, Coral growth, Coral nurseries, Polhena reef

An assessment of the effects of hospital wastes released to Nilwala river, Matara

Wastewater from hospitals either treated or partially treated can alter water quality and biological diversity in adjacent water. This study focused to assess effects of hospital wastes discharged from the General Hospital Matara to the Nilwala River. Two sampling sites were located upstream of the entrance of wastewater while two sites were located downstream of the entrance of wastewater discharge and one site was selected at the entrance of the wastewater channel. Water, sediment and plankton samples were collected biweekly during February to April, 2012. Nitrate, phosphate, pH and Cu concentrations in water sampled from the hospital wastewater discharging canal were significantly (One-way ANOVA, p&lt;0.05) different from the other sampling sites. However, Cu concentration in surface water did not exceed the EU limits of 0.0005-0.112mg/l for fisheries and aquatic life and similarly water pH did not exceed the maximum allowable limit (6-8.5) for fisheries and aquatic life in Sri Lanka. Mean concentration of Cu in sediment collected at the entrance of the wastewater channel was 0.75±0.05 mg/g dw. Although total coliform concentration (MPN/100ml) did not vary significantly among the sampling sites, it was relatively low (39.66±17.7) at the waste discharging canal due to the presence of disinfectants in hospital wastewater. Pediastrum simplex was the most abundant phytoplankton species at all the five sampling sites. Cladocera was the most abundant group of zooplankton in all the sites except at the entrance of wastewater discharging canal and Protozoa was the most abundant group present at the wastewater discharging canal. According to rotated matrix of Principle Component Analysis (PCA) water pH, PO4−3, NO3−, TDS, Salinity and Zooplankton abundance can be considered as important parameters at the study site of wastewater entrance (site 3). The toxicity (72h EC50) of hospital wastes on Pediastrum simplex was 0.08 Toxic Units (TU) and it was not an acute toxic effect on the alga when compared with hazard classification systems for wastes discharge into the aquatic environment. DOI: http://dx.doi.org/10.4038/jur.v2i1-2.7852 J. Univ. Ruhuna 2014 2:33-39

A Local Level Technology and Policy Intervention Approach to Restore Paddy Ecosystems in the Nilwala Downstream, Affected due to Nilwala Flood Protection Scheme, Southern Sri Lanka

Present paper discusses the innovative approach and the strategies adapted for policy impact, by the Asian Disaster Preparedness Centre along with stake holder institutions to restore paddy ecosystems affected due to the introduction of a flood protection scheme for the down-streams of the Nilwala river basin located in the Matara District, southern Sri Lanka.The project helped in studying the problems and addressing the policy issues while mainstreaming climate information applications in order to reduce the vulnerabilities associated with paddy farming by rallying all stake holders (academia, local level government institutions, farmer organizations & media) under the leadership of the Matara District Secretary to form a local Management and Monitoring Committee which helped in identifying the most effective policy framework. It has also helped in addressing the main issues related to climate, plant, soil, water and social problems through technology intervention and adapting them to improve farming systems.

Spatial and temporal variabilities of groundwater characteristic distribution in the Nilwala River Basin

The study was conducted in Southern Sri Lanka which is bound by longitudes 80.50 E and 80.59 E and latitude 5.59 N and 6.07 N in the Right Bank of Nilwala river Basin. This study aimed to identify corrective and behavior of the groundwater quality changers, present groundwater levels fluctuations with precipitation and groundwa ter consumption of the region. Groundwater is the major water source in the study area, where shallow uncon fined groundwater is used for domestic purposes and irrigation. To determine the hydrogeological conditions and groundwater quality distribution, conduct monitoring by selecting 60 (sixty) dug wells with respect to water level, electrical conductivity (EC), total dissolved solids (TDS), major cations and pH from January 2006 to May 2007. The dug wells are sunk into the permeable quaternary deposits overlying Precambrian granite gneiss and unconfined aquifer mainly consist with laterite and sandy clay. The study helped to prepare hydro geological map and the distribution of EC, TDS and pH maps using the GIS package Arc view. Hydrogeological map help to identify recharge and discharge areas of the study area. The pH of the groundwater remains 4.5 – 6.5 and it usually decreases within a small range consequent to rains and EC fluctuation was in the range of 200 – 600 S/cm. Chemical analysis indicates that iron concentration is high in some areas which has more favorable situation for pyrite formation. The characteristic of hydrographs provide conclusion in the unconfined quaternary aquifer ground water level intimately related to atmospheric precipitation and recharge of aquifer takes place during the rain periods.