Chandra Jayasena | University Of Peradeniya,Sri Lanka (original) (raw)

Papers by Chandra Jayasena

Marine Pollution Bulletin, Jun 1, 2023

Exposure and Health

The principal goal of the current study is to assess perchlorate contamination of groundwater and... more The principal goal of the current study is to assess perchlorate contamination of groundwater and related health risks from the fireworks manufacturing area (Sivakasi) in South India. Seventy-four groundwater samples were gathered and analysed for electrical conductivity (EC), pH, total dissolved solids (TDS), sodium (Na+), magnesium (Mg2+), calcium (Ca2+), potassium (K+), sulphate (SO42−), bicarbonate (HCO3−), chloride (Cl−), fluoride (F−), nitrate (NO3−), and perchlorate (ClO4−). Perchlorate ranged from 0.00 to 0.21 mg/l with an average of 0.08 mg/l. About 61% of the samples (n = 45) contained higher perchlorate concentrations than the recommended level (0.07 mg/L) of World Health Organization (WHO). Similarly, 360.18 km2 of area exceeds the permissible limit of perchlorate as per WHO. Correlation analysis indicates that groundwater contamination is mainly caused due to anthropogenic activities. Vertical distribution results indicate that 52% of the samples fall in the ‘high-risk’ category, 39% of the samples fall under the ‘very high-risk’ category and 9% of the samples fall under ‘safe’ category in the shallow aquifer of depth up to 15 m from the ground level. Total Hazard Index (THI) results reveal that about 70%, 60%, and 40% of the samples are more vulnerable (THI > 1) for infants, children, and adults. This study suggests that higher health risks inferred for infants must be cared with a suitable management plan to recover the quality of the water to evade major health problems in the future.

LARHYSS Journal P-ISSN 1112-3680 / E-ISSN 2521-9782, Sep 30, 2021

Proceedings of the International Association of Hydrological Sciences, 2018

Ceylon Journal of Science, 2021

Journal of Asian Earth Sciences, 2019

Review of Palaeobotany and Palynology, 2018

Slope failures causing landslides are common in many parts of Sri Lanka, particularly along the m... more Slope failures causing landslides are common in many parts of Sri Lanka, particularly along the major roads. Typically, conventional roller-compacted concrete or rubble-masonry structures have been used to mitigate such events but these methods have drawbacks, including the length of time taken to construct such structures. Therefore, alternative methods for stabilizing hazardous slopes need to be investigated. Among the alternative approaches are soil nailing, which involves the insertion of steel rods into an unstable slope to pin it in position, and soil bioengineering, which involves spraying a mixture of grass-seeds, other seeds and fertilizer onto a suitable matrix so that when the seeds germinate, the roots hold the underlying soil in place. Both methods can help to reduce construction times so that work can be completed before the onset of the annual rainy season. Soil-nailing and soil-bioengineering methods were introduced into Sri Lanka by Soil Tech Ltd., a private company.

A sequence of rhythmic varve like sediments within the valley of Weuda and isolated sand and grav... more A sequence of rhythmic varve like sediments within the valley of Weuda and isolated sand and gravel deposits in the northwestern plains of Sri Lanka, were reinvestigated. Inter-bedded peaty clay and sand intercalating with un-weathered feldspar, striated and faceted pentagonal quartzite pebbles, “U” shaped valley flanked with large boulders, isolated occurrences of poorly sorted white angular sands, ferruginized gravels and Permo-Triassic plant microfossils all favored a glacial origin for these sediments. However, Paleozoic glacial features appear to be either obliterated or erased due to post-glacial neotectonic movements, large scale pluvial processes, effects of denudation and intense tropical weathering. Study on provenance indicates that Paleozoic glacial deposits may have mixed with or covered by subsequent sediments.

Water supply to arid areas by many ancient communities around the tropical and subtropical region... more Water supply to arid areas by many ancient communities around the tropical and subtropical regions was unique, where the conveyance mechanism had been developed based on morphological, geological and meteorological factors. However, to maintain the longevity and sustainability of these water supply systems, effective environmental management is imperative. Many medieval communities throughout these regions have practiced runoff harvesting to groundwater conservation in order to lead a sustainable life with the available rainfall. We postulated that integrated environmental criteria based on sound technical principles were fundamental for the establishment of the Tank Cascade (TC) and the Qanats irrigation systems. To carry out a comparative study and to investigate such mechanisms, we selected a dry zone catchment in the northwestern province of Sri Lanka and a Qanats based irrigation system in Iran. The TCS has evolved as a network of hydraulic structures, which have harnessed the ...

Rural communities in the dry regions are continuously struggling with the meagre water resources ... more Rural communities in the dry regions are continuously struggling with the meagre water resources available to satisfy their daily household and agricultural needs. A pilot study conducted among 250 households from Aladeniya, Hedeniya, Weerakodiyana, Rakogama and Chilaw in the Deduru Oya basin during the period from 2002 to 2005 revealed that 80% of their daily needs are met with groundwater obtained from dug wells and tube wells. Approximately 82% of their average per capita daily domestic water consumption of 110 L was utilized for bathing while the remaining 18% was used for drinking, cooking, washing and toilets. The socio economic inputs show that the household income varies from Rs. 5,000/= - 15,000/= per month.And their willingness to pay for a reliable water supply system is little over 1.5% of their income, which is encouraging but very low to implement a modern water supply scheme. The average annual rainfall is 1600 mm, however geohydrologic environment is not conducive fo...

Hydraulic properties obtained from pumping tests conducted in sedimentary and hard rock aquifers ... more Hydraulic properties obtained from pumping tests conducted in sedimentary and hard rock aquifers in Sri Lanka were examined. The test data were collected from Water Resources Board and National Water Supply and Drainage Board databases. The data were initially divided based on geology and treated separately. In the analysis, attention was paid only to 24 hr pumping tests and 72 hr recovery tests to minimize interferences. Theis's and Jacob's methods were used to evaluate the data before further analysis. Regional variations in the transmissivity (T) and storage co-efficient (S) of the aquifers were identified. The test data indicated that T and S vary from 1-1130 m 2

Infrastructure development needs engineering judgments for which expensive geotechnical investiga... more Infrastructure development needs engineering judgments for which expensive geotechnical investigations are the prerequisite. Alternatively, few data points could model using geostatistics to obtain meaningful outcome. To test this, a project was formulated with 129 borehole data collected from the Kandy City Wastewater Project in Sri Lanka. Statistical analysis was initially conducted on declustered data plus supplement field data. After eliminating drift and removing extreme values, kriging were performed to obtain contour patterns. The depth to bedrock (DBR) contours show clear relation with lithology, fracture pattern and the topography. Quartzite and charnockite show shallow depths whereas marble and garnet sillimanite biotite gneiss show deep depths. However, deviations were observed in areas where anthropogenic inputs and exogenous processes are active. Depth to water table (DWT) and lithology does not show any relationship, however, DWT show compatible relationships with topo...

Applied Geochemistry, 2015

Marine Pollution Bulletin, Jun 1, 2023

Exposure and Health

LARHYSS Journal P-ISSN 1112-3680 / E-ISSN 2521-9782, Sep 30, 2021

Proceedings of the International Association of Hydrological Sciences, 2018

Ceylon Journal of Science, 2021

Journal of Asian Earth Sciences, 2019

Review of Palaeobotany and Palynology, 2018

Applied Geochemistry, 2015

A classic example of urban-rural linkages through ancient Yoda Ela in Sri Lanka - Symbiosis of to... more A classic example of urban-rural linkages through ancient Yoda Ela in Sri Lanka - Symbiosis of total environment on efficient water management

H. A. H. Jayasena
Department of Geology, University of Peradeniya, Peradeniya 20400, Sri Lanka
(corresponding author phone: +94-727-435-161; fax: +94-812-388-018; e-mail: cjayasena@ pdn.ac.lk)

Abstract
Among the ancient irrigation practices, the Sri Lankan dry zone water management systems sustained for over 2000 years have been well documented. With the influx of communities settling around the historical urban centers, efficient water management was necessary. The invention of the Tank Cascaded system (TCS) and a network of canal systems have emerged to supply water to these centers, which lasted even at present. This paper aims at unraveling some unique functions of the Yoda Ela (YE) canal located in the northern dry zone connecting Kala Wewa (reservoir) with Tissa Wewa. After examining the aerial photographs, Google Earth Pro, and Digital Elevation Models (DEM) followed by field investigations to assess the respective environmental changes, it was evident that the water supply from a transboundary canal took place with the utmost care and in a sustainable manner. Minimal hydrochemical variations and sediment migration coupled with well-maintained irrigation and domestic water supply sustain the community living around this 87 km long canal. The Yoda Ela is one of the excellent representations exemplifying the urban-rural linkages from the total environment and global water history perspectives.

Keywords—Total environment, Dry zone irrigation, Sustainability, Yoda Ela, Urban-rural

Proceedings ICEWW 2020: 22nd International Conference on Environment, Water and Wetlands, 2020

Yoda Ela (YE) located in the northern dry zone of Sri Lanka has been an irrigation marvel sustain... more Yoda Ela (YE) located in the northern dry zone of Sri Lanka has been an irrigation marvel sustainably existed for over 1500 years without any break except for the recent politicized decisions abandoning its functions. A study was conducted on its geoenvironmental regime and compared with modern New Jaya Ganga (NJG) which replaced YE with rapid and high discharge straight channel. The examination of aerial photographs, Google Earth Pro and Digital Elevation Models (DEM) followed by field investigations assess the respective environmental changes. Thirty-one water samples were also collected from both YE and NJG at different discharges aiming at measuring turbidity variations. A theoretical model based on the application of the function of sinuosity developed by Langbein and Leopold in 1966 was applied for 12 meander segments from YE. The slope, sinuosity [K], angle [ω], wavelength [λ], amplitude [A] and the radius at curvatures [Rc] of respective meanders were then measured. The output of these meander sections tracks a sinusoidal fitting to a modified sine curve may be resultant due to the construction of a headwater canal. The DEM indicated that the ancient YE follows the topographic contours when conveying water from Kala wewa to Tissa wewa but NJG is not. The positioning of the single embankment of YE has a direct relation to the drainage divide of the basins. Turbidity gradually decreases along its path however current inadequate flow may inherit algal boom at places causing the local increase. Meandering produces a sustainable environmental flow along with the ancient YE. A further analysis on flow parameter calculations, sediment analysis, landforms analysis with DEM, Google Earth, air photo and drone studies are expecting.

34th Annual Session, GSSL, p24, 2018

Construction dewatering has been a routine requirement, however, constricted by the regulatory-dr... more Construction dewatering has been a routine requirement, however, constricted by the regulatory-driven megacities such as Greater Toronto Area (GTA) in Canada. The hydraulic conductivities (K) obtained through experimental approach; percolation, infiltration and slug tests and empirical approach; particle size distribution (PSD) based formulae, resulted in providing necessary guidelines and directives to prospective buyers, developers or authorities in terms of completing their due diligence. The following K’s obtained by Orbit for glacial terrains in Ontario resulted in a range of arithmetic averages. For aquifers of sand and gravel; 4.4E-02, sand to silty sand; 3.8E-04, sandy silt/silty sand till; 1.03E-04, clayey silt/silty clay with fine sand; 4.70E-05 and for aquitard of clayey silt till; 4.52E-06 cm/s, which clearly follow the observed trend in GTA. However, the results of the PSD output gave somewhat higher average ranges, 4.72E-02 to 6.16E-02 for sand and gravel; 1.8E-03 to 3.3E-04 cm/s for sandy silt till with some clay. The respective guidelines adhered by GTA to allow discharge permits consider horizontal flow with the highest applicable point K. The recent collapse of high rising buildings in Megacities and excessive dewatering along with Uma Oya tunnel highlights the dire need for Sri Lanka on implementing similar regulations to those in GTA and other parts of the world in order to cope up with the environmental quality and safety issues. The K (Transmissivity (T)/assuming 30m aquifer thickness) and Storage Coefficient (S) data acquired from tunnel construction, dam building and pumping tests within the fractured basement resulted with ranges from 3.24E-05 to 2.8E-02 cm/s and 0.0001 to 0.5 respectively. These values assume homogeneity and isotropy which are not coherent with reality as observed in the fractured rocks and marble formations in Sri Lanka. As the Sri Lankan basement consists of regolith (10m thick) progressing towards highly transmitting semi weathered rock over to the subsurface fractured network (30m thick), the proposed infrastructure confined at such depth levels should expect scale effect. Therefore, to obtain satisfactory K would be a difficulty. However, reasonable assessments on individual cases should be available to the decision maker. Since the guidelines for extraction, discharge and conveyance have not yet been codified in Sri Lanka, the consequence will clearly result in difficult social outcome unless the government authorities or accredited institutes intervene to implement a regulatory framework.

Keywords: Construction dewatering, hydraulic conductivity (K), Transmissivity (T), Storage Coefficient (S), regulatory framework, glacial, hard rock, Orbit, Sri Lanka, Canada

Acknowledgements: The first author acknowledges the University of Peradeniya for giving him the opportunity to spend his sabbatical leave at the Orbit Engineering, Brampton, Canada.

Sustainability: Transdisciplinary Theory, Practice, and Action STTPA Conference 2019 @ University of Toronto Mississauga October 16 - 18

Sri Lanka has moderate water stress (on a scale of 5), with sector-wise scores for agriculture (3... more Sri Lanka has moderate water stress (on a scale of 5), with sector-wise scores for agriculture (3.10), domestic (2.28) and industry (2.65). The expected climate change scenarios (1.2-1.6°C increase), however, aggravates water for agriculture (paddy 13-23% increase) and industry requirements (6.42% increase). Since IPCC suggests degrading water quality, a study was performed on historical irrigation systems. The results show evidence of sustainable household and farm-level water management as inherited from the well-endowed indigenous knowledge, though 85% were aware of water shortage due to drought coupled with climate change. In agricultural areas 40% discharge their wastewater to the household plants however no such use in townships but 50% to open areas. Modern irrigation with ad hoc policies resulted in invasive plants, reduction of annual discharge, increasing sedimentation/erosion and 85% see lower quality water due to agrochemicals. The outcome necessitates the need to reevaluate the indigenous practices in water governance as a multifaceted approach in achieving SDG 6.

35th Annual Technical Session, GSSL, 2019

The hydrogeological regime covering a section passing from Anamaduwa to Kalpitiya peninsula in no... more The hydrogeological regime covering a section passing from Anamaduwa to Kalpitiya peninsula in northwest Sri Lanka was examined to understand the groundwater flow regime across the metamorphic and sedimentary rock terrain. The study was conducted as a hydrogeological survey based on a structured questionnaire (n=82) on the consumption, fluctuation and supply of water in the areas, supported by field examination of dug and tube wells. In Kalpitiya average water level fluctuation was 4.14 m (vary from 2.25 to 6.39 m) while it was 5.57 m (vary from 2.95 to 8.52 m) in the Anamaduwa-Puttalam area. Drinking water supply in Kalpitiya was 24 hours irrespective to the dry or wet climate. However, the water supply was on average 14 hours per day during the dry period in the Anamaduwa-Puttalam area while it may extend up to 21 hours per day during the wet periods. Average domestic water consumption in the Kalpitiya area is about 72.4 L/person/day while in Anamaduwa-Puttalam area it is 81.5 L/person/day. In the Anamaduwa-Puttalam area, EC varies from 479 to 35,420 µS/cm (average 3,336 µS/cm) whereas the TDS vary from 319 to 23,360 mg/l (average 2190 mg/l). In Kalpitiya peninsula EC varies from 339 to 5980 µS/cm (average 1457 µS/cm) whereas the TDS vary from 223 to 3847 mg/l (average 962 mg/l). The Higher EC (>2500 μS/cm) and TDS (>2000 mg/l) observed along with faulted basins in Andigama-Anamaduwa area and near the boundary between Wanni complex and limestone belt are hydrogeologically responsible and could be due to barring of groundwater flow. Seawater intrusions along with sandy aquifers in Kalpitiya peninsula are responsible for the EC/TDS variations, however, indicate better prospects compared to landward areas. The outcome indicates the future water sector challenges (target 6) to achieve the Sustainable Development Goals in the study area.

Keywords: NW Sri Lanka, Water consumption, dry Zone, hydrogeology, SDG

Proceedings Water Future Conference, 2019

MODERNIZATION EFFECTS ON SUSTAINABLE WATER ALLOCATION YODA ELA SRI LANKA Ranathunga, B.P.D.W.1,... more MODERNIZATION EFFECTS ON SUSTAINABLE WATER ALLOCATION YODA ELA SRI LANKA

Ranathunga, B.P.D.W.1, Chandrasena, M.G.P.N.2, Jayasena, H.A.H.3 and Chandrajith, R.3

1.National Building Research Organization, 99/1, Jawatta Road, Colombo 00500, Sri Lanka.
2.Post Graduate Institute of Science, University of Peradeniya, Peradeniya 20400, Sri Lanka.
3.Department of Geology, Faculty of Science, University of Peradeniya, Peradeniya 20400, Sri Lanka.

ABSTRACT
The ancient “Yoda Ela Canal” (YEC), which drives water from “Kala Wewa” to “Thissa Wewa” reservoirs in the dry zone of Sri Lanka, has been abandoned with the recent reconstructions of new “Jaya Ganga Channel” (JGC). A questionnaire-based survey (N = 50) supported by 19 groundwater and 12 surface water samples collected from 11 locations along YEC was used to assess the people's perception, geochemical characteristics, longitudinal variations and suitability of water for drinking and irrigation purposes. Electrical Conductivity (EC), Residual Sodium Carbonate (RSC), Sodium Adsorption Ratio (SAR), Kelley’s Ratio (KR) and Magnesium Hazard (Mg Haz.) were evaluated to map the longitudinal variations. Suitability of YEC water for irrigation purposes was classified based on the US salinity diagram. The EC, RSC, KR and Mg Haz show cumulative variations along with the longitudinal profile from good to doubtful water qualities. Statistical analyses including cluster analysis (CA), correlation matrix and principal component analysis (PCA) were performed on data and the results suggest significant influences of geogenic processes on both surface water and groundwater systems. For both systems, the Piper diagram indicates Ca-Mg-HCO3- types while the Gibbs diagram depicts rock dominant processes. The questionnaire survey indicated that the impacts of agrochemical pollution along with the YEC refrain the community to drink water from the open source. The overall analyses specified that both surface and groundwater systems along the YEC were progressively inﬂuenced by the rock-water interaction and anthropogenic inputs. Though the majority believe JGC increases the water supply, the overall system has been deteriorating in terms of sustainability, longevity and agrochemical usage. The study clearly indicates that the time-tested sustainable water allocation from ancient YEC is gradually obliterated by modernization and anthropogenic impacts.

Yoda Ela, Jaya Ganga, water chemistry, sociotechnology, Sri Lanka

Highlights (50 words) *
Politically motivated reconstruction of modern Jaya Ganga Channel (JGC) over the ancient Yoda Ela canal (YEC) has obliterated the sustainable water allocation and livelihood of farmers. Both surface and groundwater quality along the YEC are inﬂuenced by the rock-water interaction due to deepening of YEC and heavy agrochemical usage.

Summary (150 words) *
Groundwater (19) and surface water (12) samples from 11 locations along YEC were analysed to assess geochemistry and drinking and irrigation suitability. Electrical Conductivity, Residual Sodium Carbonate, Sodium Adsorption Ratio, Kelley’s Ratio and magnesium hazard variations show water quality varying from good to doubtful along the YEC. Cluster analysis, correlation matrix and principal component analysis were performed, and the results suggested significant influences of geogenic processes on both surface and groundwater systems. For both systems, the Piper diagram indicates Ca-Mg-HCO3- types while the Gibbs diagram depicts rock dominant processes. A questionnaire survey (N=50) indicated that agrochemical pollution was increased towards the downstream refraining community to drink water from the open-source. The majority believe JGC increases the water supply, however, it has been deteriorating in terms of sustainability, longevity and agrochemical usage. The study clearly indicates that the time-tested sustainable water allocation from ancient YEC is obliterated by modernization and anthropogenic impacts.
Overall Introduction and objectives (100 words) *
The ancient YEC carries water from Kala Wewa to Thissa Wewa reservoirs in the dry zone of Sri Lanka. The YEC sustained over 1500 years providing quality irrigation water and sustainable livelihood. However, the construction of JGC severely affects sustainability. The study aims at understanding the YEC flow regime, in terms of its geochemical variations of surface and groundwater, and environmental changes and damages. In addition, the suitability of water for drinking and agriculture are duly assigned for the study so that the pros and cons of the modernization process would be tested.

Methodology Approach with the description of the innovative approaches or analytical tool (200 words) *
The literature on YEC and JGC were compiled for a preliminary assessment. The data on geology, structure, morphology and dry zone tank cascade systems was also collected through primary sources before fieldwork starts in the selected areas. A questionnaire-based survey (n = 50) was used to assess people's perception. Nineteen groundwater from surrounding wells and twelve surface water samples were collected from 11 locations along YEC to asses the geochemical variations and suitability of water for drinking and irrigation purposes. The water samples were collected into polyethylene bottles (500 ml bottles for anions and 100 ml bottles for cations) that sank in 10% HNO3 overnight and washed with distilled water. Each 100 ml sample was filtered and acidified by conc. HNO3 acid to prevent the cations loss or change due to adsorption or exchange with a wall of the bottle. Water and air temperatures, pH, electrical conductivity (EC), and Total Dissolved Solids (TDS) of water were measured using portable meters. Major cation and anion concentrations were measured in the lab. For both surface and groundwater systems, the Piper and Gibbs diagrams were prepared. The GIS and statistical software were used to construct maps, longitudinal profiles, cluster analysis, correlation matrix and principal component analysis.

Why is the current approach/innovation relevant? What are the benefits and for whom? (100 words) *
It has been noted that politically motivated systems usually geared for short term goals ended up with miscalculations of the expected output. A classic example is the conversion of ancient YEC, which supported the sustainable livelihood, to a modern JGC obliterating expected overall benefits. The present study aims at unravelling the cumulative effects when the anthropogenic elements work on building unsustainability. Anthropogenic inputs and agrochemicals causing a severe backlash to the time tested sustainable total environment associated with the YEC. We believe the paper highlights the repercussions of ad hoc decision making without major concern on environmental goals.

Analysis and results with examples of actual application of the scientific innovation or activity or analytical tool (200 words) *
The EC, Residual Sodium Carbonate (RSC), Sodium Adsorption Ratio (SAR), Kelley’s Ratio (KR) and magnesium hazard (Mg Haz.) show variations along with the longitudinal profile of YEC from good to doubtful water qualities. Irrigation suitability based on the US salinity diagram indicates medium to high salinity hazard in most locations. The physical parameters and chemical concentrations of anions and cations are used as variables for the cluster analysis and the results show surface water quality varies from good to bad towards downstream. The dendrograms are performed separately for surface and groundwater system. Principal component analysis (PCA) results suggested significant influences of geogenic processes on both surface and groundwater systems. The Piper diagram for both systems indicates Ca-Mg-HCO3- types while the Gibbs diagram depicts rock dominant processes. The questionnaire survey indicated that agrochemical pollution was increased towards the downstream of the YEC refraining community to drink water from the open-source. The overall analyses indicated that both surface and groundwater systems along the YEC were inﬂuenced by the rock-water interaction and anthropogenic inputs.
Conclusions and recommendations (100 words) *
The overall analyses indicated that both surface and groundwater systems along the YEC were inﬂuenced by the rock-water interaction and anthropogenic inputs after the construction of new JGC. Though the majority believe JGC increases the water supply, the overall system has been deteriorating in terms of sustainability, longevity and agrochemical usage. The study clearly indicates that the time-tested sustainable water allocation from ancient YEC is obliterated by modernization and anthropogenic impacts. It is recommended that political driven motivation on the reconstruction of existing ancient irrigation networks need prior evaluations considering total environmental issues before implementation.

Water and food security are considered key components of the climate change driven environments t... more Water and food security are considered key components of the climate change driven environments throughout the world. The outcomes of water, food, and governance on peoples living standards in rural areas supplied with irrigation water and peri-urban townships supplied with pipe borne water in Sri Lanka were examined. Socio-technical control of water supply through irrigation structures for the community living in the dry zone was striking however with the current global trend on market-driven economies it is being threatened. Four different areas; Weerakodiyana and Yoda Ela from agricultural communities, Chilaw from a fishing community and Aladeniya from merchant families in the peri-urban area were selected. The field surveys were conducted in 2004 and 2016 respectively selecting 50 families from each area. Irrigation based on hydraulic technology spread in areas around Yoda Ela and Tank Cascade System (TCS) in Weerakodiyana indicate the positive output of social and ecological sustainability that cannot be treated as an isolated system. Considering the analytical results from different perspectives, the peri-urban market regulated economy driven in Chilaw and Aladeniya townships indicate the diverse outcome. Based on Contingent Valuation Method (CVM) the mean monthly income-expenditure observed in the US $ for Yoda Ela: 224-212, Weerakodiyana: 63-59, Chilaw: 123-125 and Aladeniya: 152-103. Necessities of current population revealed food, clothes, housing, and water for agriculture with low priorities (1.5-2.5 except Chilaw and Weerakodiyana), whereas jobs, good government, market and labor requirements with high priorities (4.0-5.5 except Chilaw) in a coded scale of 7. The results indicate that there is no major food and water security issues in the study area, however, the current market-driven economy implanted on the community by the recent governments drive self-centered interests posing severe backlash to the traditionally sustainable farming and fishing community in Sri Lanka.

Water and food security are considered key components of the climate change driven sociotechnical... more Water and food security are considered key components of the climate change driven sociotechnical environments throughout the world. The outcome of water, food, and governance on peoples living standards in rural areas supplied with irrigation water and peri-urban villages supplied with pipe borne water in Sri Lanka was examined. Socio-technical control of water supply through irrigation structures for the community living in the dry zone was striking however with the current global trend on market-driven economies it is being threatened. Four different areas; Weerakodiyana and Yoda Ela from agricultural communities, Chilaw from a fishing community and Aladeniya from merchant families in the peri-urban area were selected. The field surveys were conducted in 2004 and 2016 respectively selecting 50 families from each area. Irrigation based on hydraulic technology spread in areas around Yoda Ela and Tank Cascade System (TCS) in Weerakodiyana indicate the positive output of social and ecological sustainability that cannot be treated as an isolated system. Considering the analytical results from different perspectives the peri-urban market regulated economy driven in Chilaw and Aladeniya townships indicate diverse outcome. Based on Contingent Valuation Method (CVM) the current mean income in US $ for Yoda Ela: 224, Weerakodiyana: 63, Chilaw: 125 and Aladeniya: 151. Necessities of current population revealed food, clothes, housing, and water for agriculture were given low priorities (1.5-2.5 except Chilaw and Weerakodiyana), whereas jobs, good government, market and labor requirements were given high priorities (4.0-5.5 except Chilaw) in a scale of 7. The results indicate that there is no major food and water security issues in the study area, however, the current market-driven economy implanted on the community by the recent governments drive self-centered interests posing severe backlash to the traditionally sustainable farming and fishing community.

This dataset provides information gathered from 50 families each from Weerakodiyana, Rakogama, He... more This dataset provides information gathered from 50 families each from Weerakodiyana, Rakogama, Hedeniya, and Chilaw, and another 30 families from Aladeniya in the Deduru Oya basin. They were collected in 2003-2006 period with the supports from Tharuna Aruna Skilled Development program conducted through Soil Tech (Pvt.) Ltd. This data comprised of basic socio-economic, water usage, water purification and disposal at the House Hold level. This is a subset of the original larger data set which will be available in due course after completion of the detailed analysis

Sri Lanka is blessed with an average annual rainfall of 2000mm. This rainfall is sufficient enoug... more Sri Lanka is blessed with an average annual rainfall of 2000mm. This rainfall is sufficient enough for yearly domestic and agricultural requirements, provided that proper storage facilities with regulated runoff practices could be implemented. However, the dry zone with an annual rainfall of less than 1900mm faces both spatial and temporal water shortages. This study aims to investigate several points such as the current domestic water needs, possible future water supply mechanisms, willing to pay (WTP) for domestic water by rural village community in the Deduru Oya basin and management options
for efficiency. A structured survey was conducted for 180 families randomly selected from Hedeniya and Aladeniya in the wet zone as well as Rakogama and Weerakodiyana in the intermediate
zone. The results show that the average daily usage for drinking, cooking and sanitation is 115 l/p/d (liters per person per day) out of which more than 70% is used for bathing. Currently 65% use dug wells and another 16% use Tube wells while pipe born water supply is available for only 6% of the families. Contributors believe domestic water supply programs could be organized through dug wells and tube wells; however reservoirs and streams could be added in the lowland planes too. The satisfaction
over water supply and maintenance by different agencies such as government, provincial councils, private sector, NGO, foreign agencies, regional councils and other agencies were also examined. The
contributors prefer water supply and maintenance responsibilities be handled by the central government. However, more than 60% of contributors from Hedeniya were extremely satisfied with NGO
and Foreign Agency involvement, since a FINNIDA supported water supply and sanitation project was successfully completed in Hedeniya. Major complaints of these projects were the inadequate maintenance
and inefficiency of officials. A WTP survey was conducted for future water supply projects anticipated in these villages where the monthly income varies from Rs. 5000 in Hedeniya to more than
Rs.15000 in Aladeniya. This survey indicates community agreement for allocation of at least 1.5% from the average monthly income. However, contributors from severe water shortage areas such as Rakogama and Hedeniya prefer allocation of more than 3.5% from the average monthly income even though their average expenditure was below the average poverty set at Rs. 1423 /p/month (per person per month). The study concluded that strong government subsidies are needed in water supply projects. People expect strong management initiatives in order to provide efficient water supply programs in Sri Lanka

Prior assessment of geotechnical property variations of soils is valuable and could drive to redu... more Prior assessment of geotechnical property variations of soils is valuable and could drive to reduce the number of field and laboratory tests during efficient management of design and construction of infrastructure projects. Here we aim at assessing geotechnical relationships for residual, alluvial, marshy, coastal, and compacted soils within the wet and the dry zones of Sri Lanka. Plastic limit (PL), liquid limit (LL), shrinkage limit (SL), plasticity index (PI), liquidity index (LI), compression index (Cc), swell potential (SP), activity, natural moisture content (NMC) and SPT-N values, were either extracted from reports or deduced from formulas and graphs. Wet zone Marshy soils (My_W) show highest statistical means for PL (~23%), LL(~40%), PI(~16 %), SL(~20 %), LI(~ 1), Cc (~ 0.200) and NMC(~ 35%), indicateing poor engineering properties. Wet zone residual soils (Re_W) represent a wide range with direct correlation to the parent material. CH, OH, CL and SM soil groups for some My_W show high expansive, while, CL, Pt/CL, OL, SC, SM in My_W, CL and SC in Re_W and CL in Dry Zone Alluvial Soils (Al_D) display medium expansive. The higher SPT-N values were recorded in the upper 6.00m and between 12.00-16.00m for Shell of Dry Zone Earth Dams (SED_D), in contrast, Al_D represent higher N values for 6.00-12.00m zone. Except for marshy soils, no vertical variation for plasticity was observed. Since high to medium swell potential and unsaturated zone are encountered within the upper 1.50m, attention should pay to the My_W. LL and PI of My_W were strongly correlated (R2 = 0.83) so that PI% = -1.91 + (0.46*LL%) could be used to calculate PI. The results provide baseline geotechnical property variations for the five soils, so that planning could be improved and time and cost for investigations could be cut down.

Extreme rainfall received in December 2014, cause severe landslide occurrences in many areas of t... more Extreme rainfall received in December 2014, cause severe landslide occurrences in many areas of the central highlands in Sri Lanka. Two landslides took place along Watagoda road and Dodandeniya in Matale were investigated. Subsequent landslide threat issued to Dodandeniya residents in Matale was further subjected to geological and socio economic concerns. To investigate these landslide occurrences and resultant social impacts we undertook a hydrological, geological, geophysical and socio economic surveys. These events were initiated with 440 mm of cumulative rainfall as recorded at the Elkaduwa automated rain gaging station. The measure was taken through six consecutive days from 20 th to 26 th of December where daily rainfall varies from 22 to 182 mm. The geological surveys accompanied by desktop studies and subsequent geophysical surveys indicated two different phenomena associated with the issuance of landslide and subsidence threat. One was the reactivation of older landslide represented by slumping within the crown located along the Watagoda road and en-echelon tensional cracks developed approximately parallel to the foliation plane of N65W/42N of the Garnet Biotite Gneiss. The second at Dodandeniya, subsidence was associated with suspected mobilized Marble band. Tensional cracks have developed along N60-30W in the right hand side of the landslide and approximately parallel to the foliation plane in the crown area, which then turning in to approximately N80E in the left hand side. The major rock types of the Dodandeniya area are Charnockitic gneiss, with clear cut contacts along N10E/55W, and mobilized Marble. Charnockitic Gneiss is a moderately jointed rock with two major joints planes; one approximately horizontal and the other along N35W/90. The intensity of these joints vary from 3-4/m which geometrically support for the development of rectangular blocks. However, the adjacent marble bands were inundated by colluvium from previous events causing difficulty in identification of contacts. Therefore, detailed geophysical surveys were conducted with respect to resistivity profiling and Ground Penetrated Radar surveys. Several wells including springs were also examined which indicate fluctuation of water table in the range of flowing to 1.2 m below the ground. Sudden appearance of groundwater through landmass may represent bursting of local pore water accumulation, however, presence of muddy water at several locations may indicate possible slip surface reactivation. The results provided a detailed picture of the subsurface geological and hydrogeological configuration. Previous landslides have inundated the marble bands, however, reactivation of crown area of landslides are subjected to slump while middle berm and the surrounding area underlain by marble could cause subsidence. Since 95 household families (High risk and Moderate risk) had been earmarked to be evacuated from the area, preliminary social survey indicated how people were affected due to the severity of this threat. The repercussions both to the residents and to the government are considerable since this area falls within the municipality limits. A detailed questionnaire based survey is planned since people expect clear cut instructions and government initiatives to look after this matter at length.

Introduction: Majority of Sri Lankan rural population depends on groundwater for their domestic r... more Introduction: Majority of Sri Lankan rural population depends on groundwater for their domestic requirements. The dug wells are the major source, however, springs play a crucial role in certain regions. Springs in hard rock terrains are formed at contacts of quartzite, marble and highly fractured granites with the adjacent rock. A study was carried out in Matale to evaluate the hydrogeological characteristics of springs with geology, structure, topography and weathered overburden. In hard rock terrains deeper groundwater occurs in the structural discontinuities such as joints, faults, fractures and shear zones. Favorable interconnection of these joints, fractures, faults and shear zones could make fairly good fractured aquifers, which could provide high yielding wells. The types and orientation of such discontinuities could also indicate potential pollutant migration paths. Therefore, socioeconomic impacts within the geohydrologic framework imposed significance of spring water in the total environment. Study area: The area is confined to the uplands within the central Sri Lanka around Matale. It lies within 80° 35´-80° 40´ easting and 7° 20´-7° 40´ northing and consists of series of north-south strike ridges and valleys. The selected catchment is bounded by elongated ridges with steep slopes on west and up to 35°slopes in the east. The catchment is about 25 km long while the width vary from 8.4 km in the south to 1.5 km in the north. It covers an approximate area of about 110km2. The elevation varies from 240 to 1200 m above sea level. Materials and Methods: Field mapping was carried out concurrent with yield measurements from 27 springs during rainy and dry seasons in 2010. Spring discharges were compared with geology, structure, morphology and drainage before analyzing to establish relationships. Rose diagrams and equal area plots were constructed to demarcate lineament distribution and maximum stress directions. DEM, TIN and slope analysis were prepared using ArcGIS. Borehole records were examined and using inverse distance weighted method, a 3D model was developed for the subsurface. Monthly rainfall and pan evaporation data were compared with moving averages in order to examine the performance of springs with seasonal hydro-meteorological conditions. Discharge was measured using V notch and area velocity methods, however, when the flow was a trickle time to fill a known volume was measured. Results and Discussion: Geological,
Structural and Hydrogeological framework: The basement comprises with high grade metamorphic rocks such as marble, garnet biotite gneiss, garnet sillimanite biotite gneiss ± graphite (khondalite), quartzo feldspathic gneiss, charnockitic gneiss and quartzite. Quartzite is present as minor bands within khondalite, however marble is well exposed as continuous bands. General strike of the rocks are in north south direction with few degrees towards NNW or NNE. However, dips vary from 10° to vertical showing wide variations. Major lineaments are running in E-W and N-S directions. Rose diagrams clearly show EW
and N-S system with minor NE-SW and NW-SE joint systems. Maximum stress is nearly in the north-south direction, which resulted in E-W joint set and lineaments. The area is covered by a thin mantle of weathered products either derived from the parent rock (residual) or transported material. Colluvium and residual weathered products consist of a wide range of poorly sorted material with varying sizes from boulders to clay. Alluvial materials tend to be sorted along the flood plain whereas the level of sorting depends on the provenance. Reddish brown lateritic soil is developed on the crystalline limestone and show varying
thicknesses up to 50 m. Brown sandy clay on khondalite however, contains a hardpan developed by the subsurface soil water movement. Groundwater table exposed at springs in the central valley and extended to 39 meters below ground level in the elevated rocky hinterlands. Springs: Springs are located along with marble and discharge their waters through karst formations and along solution paths of joints, fractures and coarse grains. Rainfall is the main recharging
factor for these springs which shows a bimodal distribution with a clear cyclicity. A considerable seasonal yield variations as observed at certain springs clearly reflect the rainfall distribution. The yield of rainy season varies from 20-1500 l/min while in the dry season it varies from 10-876 l/min with a general trend of increasing yields towards north. Based on borehole records and field observations, groundwater level and the bed rock surface of the study area varies from the surface up to 39 and 50m depths respectively. High yields can be envisaged in areas where springs emitting out from marble, especially when shallow water levels, significant fracture intensities and solution cavities are present. Three marble bands are prominent in the study area. There is no any systematic distribution of springs among them, however, clusters are concentrated in the middle band and in association with folding of rock layers. Four different genetic types of springs can be identified viz: 1. associated with well-developed karstic formations, 2 along with primary joints and fractures, 3. through secondary porosity and permeability, 4. locations where coarse grain marble present. Among them Matale springs are dominated by fractures and joints. Many are formed
in association with E-W and NE-SW trending fractures. However, meso scale folds are responsible for few springs. Springs are generally confined to the areas where slope angle is up to 10° within the regional catchment. Many springs are located within 50 meters from the stream indicating significant groundwater supply from the effluent system, so that the recharge is most likely originated from the rainfall in the elevated highlands. Based on cumulative discharge of 7560
l/min and assuming per capita daily requirement of 110 l, over 100,000 persons can be served by the spring water. Conclusion: This study concluded that in the heart of Sri Lankan highlands, spring water could play a major role in domestic circles. It could also effectively support small scale commercial and industrial establishments and irrigation sectors. The springs emitting through karstic formations have high yields compared with those emitting from fractures and solution cavities. Since the springs are mainly recharged by ample rainfall, they provide good yields throughout the year. The forgoing discussion reveals that springs in marble formation indicate a good potential for developing as a community water supply scheme where it could serve a one fourth of the community living in the area.

Horton Plains National Park (HPNP) is a wetland plateau located in the central highlands of Sri L... more Horton Plains National Park (HPNP) is a wetland plateau located in the central highlands of Sri Lanka. It serves as the headwaters for Mahaweli, Kelani and Walawe rivers and comprised with slow flowing watercourses and miers where wet patana grasslands and dwarf-forests are characterized. The present study aims at delineating sedimentation sequence using particle distribution and grain morphometric relationships, since they can be used as indications to determine nature, provenance and transportation. Three Russian corer samples inside HPNP and 14 undisturbed core samples from the adjacent regions of Ambewela (AMB), Pattipola (PTP), Thotupola North and Kotagala (KTG) were collected. Core samples were sliced into 1cm sections, however, every 5cm interval was analyzed using laser granulometer with the size range of 0.1-1000µm. Particle size distribution was measured using Fork and Ward (1957) method with GDADSTATv.8 program. With depth, the mean particle size (í µí± ̅) of the samples falls to coarse silt (CSi) to medium silt (MSi) ranges. For AMB sections í µí± ̅ varies from CSi (0-25cm)-MSi (30-40cm)-CSi (45-65cm) to MSi (70-100 cm) whereas for PTP section í µí± ̅ varies from CSi (0-25cm)-MSi (30cm)-CSi (35-45cm)-MSi (50cm)-CSi (55-95cm) MSi (100-120cm) to CSi (125-135cm) which indicate a rhythmic depositional nature. Meanwhile, for KTG, í µí± ̅ gives MSi (0-135cm); indicating a consistent depositional environment. All samples show very poorly sorted and very fine skewed particle distributions within the sequence of deposition under mire environment. Kurtosis for particle distribution shows leptokurtic (K>0) and mesokurtic (K=0) for CSi while platykurtic (K<0) for MSi. Particles separated through 1mm and 2mm sieves were washed, cleaned and analyzed using optical microscope to observe grain morphology. Quartz grains show angular shape, sharp edges, breakages, pitted surfaces and conchoidal fractures which may have resulted with grain-to-grain contact as in glacial sediments. However, this could be evidence for reduced transportation. Grain size distributions of AMB and PTP sediments show S shape trend from slightly silty sandy clay-sandy silty clay to slightly sandy silty clay in the SSC trigon of Blott and Pye (2012). On the contrary, KTG sediments singularly disseminated within slightly silty sandy clay. These observations suggest that AMB and PTP had undergone a rhythmic sedimentation history under an identical depositional environment whereas KTG sediments deviate from that nature. Moreover, some samples from AMB plotted away from the S shape trend which could be due to mechanical reworking of the top soil for agricultural and animal husbandry around the area. Further investigations are planned in order to scrutinize the depositional environments of HPNP, PTP, AMB deposits and to establish the chronology using palynological investigations. Acknowledgement: Funding for the project comes through Indo Sri Lanka joint projects administered by the

Sustainable development of infrastructure is a key to planned urban environments in more modern g... more Sustainable development of infrastructure is a key to planned urban environments in more modern global economies driven by industrialization. For efficient management of design and construction of such infrastructure projects, prior assessment of geotechnical property variations is valuable and could drive to reduce number of field and laboratory tests. Our study aims at assessing geotechnical relationships for residual, alluvial, marshy, coastal, and compacted soils within the wet and the dry zones of Sri Lanka. Plastic limit (PL), liquid limit (LL), shrinkage limit (SL), plasticity index (PI), liquidity index (LI), compression index (Cc), swell potential (SP), activity, natural moisture content (NMC) and SPT-N values, were either extracted from reports or deduced from formulas and graphs. Wet zone Marshy soils (My_W) show highest statistical means for PL(23.43%), LL(39.90%), PI(15.60%), SL(19.50%), LI(0.96), Cc(0.210) and NMC(35.16%), representing poor engineering properties. Whereas, wet zone residual soils (Re_W) represent wide range with direct correlation to the parent material. CH, OH, CL and SM soil groups for some My_W display high expansive, while, CL, Pt/CL, OL, SC, SM in My_W, CL and SC in Re_W and CL in Dry Zone Alluvial Soils (Al_D) are medium expansive. The higher SPT-N values were recorded in the upper 6.00m and between 12.00-16.00m for Shell of Dry Zone Earth Dams (SED_D), whereas Al_D represent higher N values for 6.00-12.00m zone. Except for marshy soils, no vertical variation for plasticity was observed. Since high to medium swell potential and unsaturated zone are encountered within the upper 1.50m, attention should pay to the My_W. LL and PI of My_W were strongly correlated (R 2 = 0.83) so that PI% =-1.91 + (0.46*LL%) could be used to calculate PI. The results provide baseline geotechnical property variations for the five soils, so that planning could be improved and time and cost for investigations could be cut down.

National Conference on Cryptogam Research in India: Progress and Prospects; Organised by the Indian Lichenological Society, CSIR National Botanical Research Institute, Lucknow, India., 2015

Record of the past climate and vegetation are often constructed using data generated ... more Record of the past climate and vegetation are often constructed using data generated from the analysis of pollen and spores alone or in association with sedimentology. Organic walled microfossils other than pollen and spores called non pollen palynomorphs (NPP), can be used to provide additional and independent information, increasedfocus onthe study of NPP has brought a greater appreciation of indicator role that NPP play in corroborating or redefining ecological interpretations. Different organic walled non pollen palynomorphs were recovered in organic residue prepared for palynological (pollen and spores) analysis of silty and sandy clay sediments in a 372cm bore hole-1, Weuda area, Sri Lanka. Non pollen palynomorphs are numerous and diversity in comparison with the very rare/scarce pollen and spore of vascular plants. They are represented by different kind of fungal spores. hyphae and fruitingbodies, algal palynomorphs of chloroplyta, chitinozoa. Botryococcus, Thecamoebians, scolecodont and other animal remains. Most fungal and algal taxa have much longer geological history than angiosperms and gymnosperms. This is the first record of NPP from Sri Lanka. A comparative analysis of NPP records from India and Sri Lanka indicates that some fungi and other NPPs recorded in the present study may be endemic to Sri Lanka, Abundance of fern sporangium along with fungal spores and dominance of microthyraceous fungi, pseudoshizae, etc indicates high precipitation in the past.

Key words:Palynology, Fungi, palaeoenvironment, Scolecodont, Chitinozoa. Thecamoebians

The present study was carried out in the Matale district to evaluate the hydrogeological characte... more The present study was carried out in the Matale district to evaluate the hydrogeological characteristics of springs with respect to the geology, structure, topography, drainage and weathered overburden. Detailed field mapping was carried out in the study area together with measurements of yields of the springs in wet and dry seasons. Yields of springs were compared with geology, structure, topography and drainage pattern of the study area. Spring discharges were measured and analyzed to find out relation with above features. Rose diagrams and equal area plot were prepared to find out the lineament pattern and maximum stress direction of the area. DEM, TIN and slope analysis map were prepared using Arc GIS software. Borehole records were analyzed to evaluate the subsurface characteristics and their correlations and relationship with springs. 3D model was developed using inverse distance weighted method for the subsurface of the area. Monthly rainfall and pan evaporation data were averaged and compared with moving average curve to examine the performance of springs with hydrometiorological condition. Springs in Matale area have been formed mainly in marble due to karstic formation, joints and fractures and grain size variation of marble. Major lineaments are present in E-W and N-S directions. Maximum stress direction for the area was directed nearly from north. It was found that springs are formed associated with lineaments and in low elevated valley areas. Comparative increase in yields of springs occurs towards north. Yields of springs do not show any considerable seasonal variation. Rainfall is the main recharging source which showed a bimodal variation with clear cyclicity. Borehole record analysis explained the highest yields can be obtained in marble and yield is higher in areas having low water level depth and low fracture depths. Development of the spring water as water supply source is possible to serve a considerable fraction of the community of the area.

Workshop (Virtual) Climate Change Impacts on Groundwater Quality and Health Issues: Review and Way Forward,, 2021

Workshop (Virtual) Climate Change Impacts on Groundwater Quality and Health Issues: Review and W... more Workshop (Virtual) Climate Change Impacts on Groundwater Quality and Health Issues: Review and Way Forward, 22-23 April, 2021. Organized by Department of Civil Engineering Sri Shakthi Institute of Engineering and Technology Coimbatore-641062, Tamil Nadu, India.

Strategic Environmental Assessment

Strategic Environmental Assessment Based Study

Food and water supply to 7.5 billion people without jeopardizing sustainability is the most diffi... more Food and water supply to 7.5 billion people without jeopardizing sustainability is the most difficult challenge laid in front of the world. A field study was conducted in 2004 to collect peoples perspectives on water, food, and governance considering 5 different areas viz; Weerakodiyana, Rakogama, Chilaw, Hedeniya, and Aladeniya from the Deduru Oya basin in Sri Lanka. Based on Contingent Valuation Method (CVM) the mean monthly household income-expenditure (in US $) observed for a family of 4 in Rakogama: 76-58, Weerakodiyana: 63-59, Chilaw: 123-125; Hedeniya: 50-44, and Aladeniya: 152-103. Contributor satisfaction from a scale of 7 revealed food, clothes, housing, and water for agriculture with satisfactory ranks (1.5-2.5 except Chilaw and Weerakodiyana), whereas job prospects, good governance, market availability and labor requirements with dissatisfactory ranks (4.0-5.5 except Chilaw). Average domestic water use for drinking, cooking, washing, sanitation, and bathing are 3.0, 4.1, 9.7, 7.0, 88.0 l/person/day respectively. Major dissatisfaction was water shortage (urban) and, drought and lack of natural sources (rural). The water quality varies with the supply source, whether dug, tube or pipe born, where salinity is the main cause in coastal lowlands and discharging areas. Turbidity, Cl, Fe, hardness, and pollutants also play significant roles. Six wastewater discharge criteria were assessed; viz; unpaved drains and natural ground (38%) domestic agriculture (38%), other methods (10%), paved drains (9%), no use (4%) and direct to rivulet (1%). People use domestic wastewater in agricultural areas (Rakogama and Weerakodiyana), whereas in Chilaw and Aladeniya the wastewater directly discharges into the ground or rivulets. People’s perceptions of water quantity and quality from the past to future offered a declining trend (except Chilaw). Population increase, forest clearing, well construction and land development are threatening to water supply, therefore, communities are willing to pay 1.3 to 4.2% of household income for instalment and maintenance over a continuous supply. The government can reliably and effectively handle such a program, however, Hedeniya community believes NGO and foreign institute do a better job. The results indicate polarized outcome from the commercialized peri-urban to agricultural rural areas. No major food and water security issues are emerging out, however, a market-driven economy with self-centered interests could severely backlash the sustainability.

Prof. H.A.H. Jayasena is a Professor in Geology at the University of Peradeniya, Sri Lanka. He earned his bachelors from Peradeniya and Post degrees from CSU, Fort Collins, and ORST, Corvallis, USA. He is a Chartered Geologist (Sri Lanka), a Provisional Member of APGO (Canada) and a Registered Practitioner in Hydrogeology of the Central Environmental Authority (Sri Lanka). He served as a consultant to dam and tunnel construction, slope stability & landslide remediation, EIA & ESA, and mining projects, in addition, to play a major role in high-end donor-driven (WB, ADB, JBIC, and UNDP) water projects. He has secured over Rs. 15 million and US$ 70,000 worth research and educational funds. He has published 53 peer-reviewed articles, 22 research reports and 56 abstracts in reputed local and international journals. He served as Chairmen of Geotechnical Engineering Companies, President of the Geological Society, and Member of the UN Geothermal Project in Sri Lanka.