Coastal Aquifer System, Kerala

Home , Adichanalloor, Bharanikkavu, Champakulam, Chittumala, Kalluvathukkal, Kannanalloor

क� द्र�यू�म भ जल बोड셍 जल संसाधन, नद� �वकास और गंगा संर�ण मंत्रालय भारत सरकार Central Ground Water Board Ministry of Water Resources, River Development and Ganga Rejuvenation Government of India

Report on MAPPING AND AQUIFER MANAGEMENT PLAN Coastal Aquifer System, Kerala

के र ल �ेत्र, �त्रवेꅍ饍गम Kerala Region, Thiruvananthapuram

भारत सरकार GOVERNMENT OF INDIA जल संसाधन, नद� �वकास और गंगा संर�ण मंत्राल MINISTRY OF WATER RESOURCES, RIVER DEVELOPMENT & GANGA REJUVENATION केꅍद्र�य भू�मजल बोड셍 CENTRAL GROUND WATER BOARD

MAPPING AND MANAGEMENT PLAN OF THE COASTAL AQUIFER SYSTEM OF KERALA

के र ल �ेत्र KERALA REGION �त셁वनꅍतपुरम THIRUVANANTHAPURAM

OCTOBER 2016

PREFACE The State of Kerala, located in the South-western tip of India, accounts for only 1.2 percent of its geographical area but is home to about 3 percent of its population. Although bestowed with copious average annual rainfall of more than 3000 mm and also endowed with large surface water resources, only a small portion of the available resources is being utilized. To overcome the paradoxical situation, a proper understanding of the disposition, extents, characteristics, status of resource and quality aspects of the water-bearing formations, is required to ensure judicious and planned utilization of this precious natural resource and its long-term sustainability. Detailed aquifer mapping studies in Kerala State were taken up with this objective, prioritizing study of the Over exploited and Critical blocks along with Coastal aquifers during the Twelfth plan. The report titled “Mapping and management plan of the Coastal aquifer system of Kerala’’gives a complete and detailed scientific account of the various aspects of the coastal aquifer system in Kerala stretching including its vertical and horizontal dimensions, flow directions, quantum and quality of the resources, of both - the shallow and deeper zones of the coastal aquifers. Voluminous data were generated consequent to hydrogeological studies, ground water regime monitoring studies, exploratory drilling, geophysical studies etc carried out in the area, are incorporated in the report. The information is further supplemented by documenting all the relevant available data collected from concerned state department. It portrays the various ground water issues pertaining to the area. Thus it provides a total and holistic solution to the water security problems in the coastal aquifers of the state. This document has been prepared under the guidance of Dr. N.Vinayachandran,Scientist D & Nodal Officer, National Aquifer Mapping Studies in Kerala, Central Ground Water Board. The data compilation work is accomplished through the sincere and painstaking efforts of Smt Rani V.R., Scientist C, Sh Santana Subramani, Scientist C, Sh C Rajkumar, Scientist C, Sh.S.Singathurai, Scientist B, Sh Vijesh, Scientist B, Sh Sreehari S, Assistant Hydrogeologist, Dr. S.Shakti Murugan, Assistant Hydrogeologist, of the Central Ground Water Board, Kerala Region, Trivandrum. I take this opportunity to thank all of them for their help and cooperation in the preparation of this report. I am also thankful to the Chairman, Members and officers of CGWB, Faridabad for their valuable guidance in finalizing this document. Thanks are also due to various organizations of Government of Kerala and Government of India for providing data required for the compilation of this document. I hope this compilation will be of help to the planners, administrators and stakeholders in the water sector in Kerala and will serve as a useful guide for the optimal and sustainable management of limited ground water resources in Coastal aquifer systems.

Trivandrum October 2016

(V.Kunhambu) Regional Director

Contents 1.0 INTRODUCTION ...... 1 1.1 Objectives ...... 1 1.2 Scope of the study ...... 1 1.3 About the area ...... 2 1.4 Geomorphology ...... 2 1.5 Drainage ...... 3 1.6 Climate and rainfall ...... 4 1.7 Soil ...... 4 1.8 Agriculture and Irrigation ...... 6 1.9 Geology ...... 7 2.0 DATA COLLECTION, GENERATION AND INTEGRATION ...... 12 2.1 Phreatic aquifer system ...... 12 2.2 Tertiary aquifer system ...... 13 3.0 DATA INTERPRETATION AND AQUIFER MAPPING ...... 14 3.1 Aquifer geometry ...... 14 3.2 Composite lithologs and VES...... 15 3.3 Soil Infiltration Studies ...... 19 3.4. Phreatic aquifers: ...... 20 3.5. Deep confined aquifers ...... 25 3.6. Warkalai beds ...... 29 3.7 Quilon beds ...... 31 3.8 Vaikom beds ...... 31 4. 0 HYDROCHEMISTRY ...... 38 4.1. Shallow ground water ...... 38 4.2. Hydrochemistry of the Tertiary aquifers ...... 38 4.3 Characterization of hydrochemical processes ...... 42 5.0 GROUND WATER RESOURCES ...... 48 5.1 Shallow phreatic aquifer ...... 48 5.2. Deeper confined aquifers ...... 49 5.3 Gound Water Resource of Warkalai and Vaikom Aquifer (Based on SIDA Project) ...... 54 6.0 GROUND WATER RELATED ISSUES ...... 55 7.0 GROUND WATER MANAGEMENT PLAN ...... 57 7.2 Water Conservation and Artificial Recharge ...... 58

LIST OF FIGURES Fig. 1.1 The Northern (N), Central (C), and Southern (S) parts of the area ...... 2 Fig 1.2: Geomorphology of the area ...... 3 Fig 1.3. Soil types in the area ...... 6 Fig 1.4: Tectonic map of Kerala coast and off shore (Prasada Rao,1984)...... 9 Fig 3.1: The geological sections along the coast between Anjengo and Pariyapuram ...... 14 Fig. 3.2 Panel diagram showing aquifer disposition in Kuttanad alluvium ...... 15 Fig.3.3 Composite logs of Lithology, SP, Resistivity and Natural Gamma ...... 16 Fig.3.4. Composite logs of lithology, SP, Resistivity and Natural Gamma ...... 16 Fig.3.5 Hydrographs of dug wells in the study area ...... 22 Fig.3.6 Depth to water level map during Premonsoon (April 2014 )and Postmonsoon (November 2014) ...... 23 Fig.3.7 Water level fluctuation with respect to decadal mean during Prempnsoon (April 2014) and Postmonsoon (November 2014) ...... 24 Fig 3.8 Panel diagram of vertical succession of geological formations in the Kuttanad area (present study) ...... 25 Fig 3.9 Sedimentary bed thickness variations in the stratigraphic sequence ...... 26 Fig. 3.10.The vertical and lateral variation in lithology along the select section lines...... 28 Fig.3.11 Panel diagram showing lateral and vertical variation in lithology ...... 28 Fig. 3.12 Isopach of Warkalai beds ...... 30 Fig 3.13 Isopach of Vaikom beds ...... 33 Fig 3.14: Aquifer Map of Vaikom Formation ...... 36 Fig 3.15: Aquifer Map of Warkalli Formation ...... 37 Fig. 4.1 The spatial variation in electrical conductivity in the Warkalai aquifer ...... 39 Fig. 4.2 The spatial variation in electrical conductivity in the Vaikom aquifer ...... 41 Fig. 4.3 (δ2H - δl8O) relationships in groundwaters of the area ...... 43 Fig. 4.4 Plot of Chloride versus δI8O in the Tertiary aquifers ...... 46 Fig. 4.5 Variation of δl8O with 14C in the Tertiary aquifers ...... 47 Fig 5.1 Map showing categorization of blocks ...... 53

LIST OF TABLES Table 1.1 : Stratigraphic sequence in the study area ...... 7 Table 2.1 Status of data collection, generation and integration ...... 12 Table 3.1 Depth of granular zones where high gamma count noticed ...... 17 Table 3.2 Soil Infiltration test results ...... 20 Table. 3.3 Trend of Pre- and Post-monsoon water levels in the study area...... 21 the the ...... 21 Table 3.4. The Top and bottom boundaries and thickness of geological formations in different stratigraphic sequences derived from bore well data ...... 27 Table 3.5. Summarised data of wells tested tapping the Warkalai aquifers ...... 31 Table 3.6: Hydraulic parameters of Vaikom aquifers ...... 34

Table 4.1Isotope sampling locations and data of 18O, 2H, 3H and14C ...... 44 Table 5.1: Groundwater Resource available in the Study area ...... 48 Table 5.2: Additional Potential Recharge for shallow water areas ...... 49 Table 6.1: Status of quality problems encountered in the study area ...... 55

Mapping and Management Plan of the Coastal Aquifer System of Kerala

REPORT ON MAPPING AND MANAGEMENT PLAN OF THE COASTAL AQUIFER SYSTEM OF KERALA

1.0 INTRODUCTION The coastal aquifer system of Kerala is having complex hydrogeological and hydro-chemical scenario associated with the tectonic history and depositional environment of the sediments. There are three major aquifer systems in the area viz; the phreatic aquifer of Recent alluvium and the Warkali and Vaikom aquifers of Tertiary beds existing under confined conditions. Also, there exists a confined to semi confined aquifer in the Recent alluvium and a confined lime stone bed (Quilon aquifer) in the Tertiary sediments. Both these aquifers are not potential either due to poor aquifer characteristics or poor quality of water. Hence, the three major aquifers were mapped in detail in 1:50,000 scale. The coastal sediments stretching almost the entire Kerala coast have maximum thickness and width in the central part falling in Alapppuzha and Kollam districts and narrows down towards north and south. The northern part is mainly reperesented by phreatic aquifer and the southern part by phreatic and Warkali aquifer of Tertiary bed. All the three major aquifers are prominent in the central part. The major constrain in conceptualizing the coastal aquifer geometry is lack of data on its seaward extention. The landward extension of the aquifer system was mapped for its aquifer geometry and groundwater resources. 1.1 Objectives The mapping of the coastal aquifer system has the following objectives. 1. Define the aquifer geometry 2. Characterize the aquifer systems 3. Evaluate the chemical quality of groundwater in time and space 4. Identify the quantitative and qualitative issues of the aquifer systems 5. Evaluation of the groundwater resources in each aquifer system 6. Prepare an aquifer map of the area 7. Evolve an aquifer management plan 1.2 Scope of the study The coastal sediments of Kerala consists multi aquifers of high potential which supports the water requirements of thick population in this area. Because of the peculiar land forms and lithological characteristics the spatial variation in water availability is high in coastal area of Kerala. The groundwater potential and geometry of the aquifer systems had been worked out earlier for a major part of the area under SIDA assisted groundwater Project during 1980s. Large scale development of groundwater in this area thereafter for water supply has reduced the heads in all piezometers. Moreover, the piezometer network is partially functional now which makes gathering information on the changes in the groundwater scenario a difficult task. Construction

Mapping and Management Plan of the Coastal Aquifer System of Kerala

of aditional piezometers and exploratory wells in data gap areas is essential to understand the present flow regime in the coastal aquifer system. 1.3 About the area The Coastal aquifer system of Kerala covers an area of about 4500 sq.km which is about twelve percentage of the geographical area of the State. The coastal plains include areas between Lakshadweep Sea in the west and elevations of 6 m above mean sea level in the east. Coastal sands and alluvium of Recent age and sedimentary rocks of Tertiary age occur in this area. Since the Tertiary sediments extend to parts of the upland area in the east, the sedimentary-crystalline rock contact has been taken as the boundary for mapping the coastal aquifer system. However, the hard rock aquifer adjoining the coastal sediments is also studied to understand the hydraulic continuity of the coastal aquifer system. The coastal plains has a width of less than 5 km in the south, increases to about 35 km in the middle and narrows down to less than 2 km in the north. The uplands in the east bordering the coastal plains have an elevation upto 40 m above mean sea level and is characterised by undulating topography. For convenience, all the maps and layers are presented as northern, central and southern parts as shown in Fig 1.

Fig. 1.1 The Northern (N), Central (C), and Southern (S) parts of the area

1.4 Geomorphology The geomorphic landforms characteristic of the coastal areas are beaches, shore platforms, spits and bars, beach ridges, estuaries and lagoons, mud flats and tidal flats.There are two low lying areas, viz. Kuttanad in Alappuzha and Kole lands in Thrissur whose levels are below mean sea level and get inundated during rainy season.The area is studded with a number of back water

Mapping and Management Plan of the Coastal Aquifer System of Kerala

channels and tidal lagoons, the notable among them is the Vembanad lake extending from north of Cochin to Alleppey. Other prominent lagoons are the Kayamkulam, Ashtamudi, Sastamkottah and Paravur. All these except Shastamkottah remain fresh and Vembanad lake remain fresh south of Tannirmukkom after the construction of the barrage except during summer.The geomorphology of the area is shown in Fig 2.

Fig 1.2: Geomorphology of the area

1.5 Drainage The coastal terrain is drained by all major west flowing rivers from Neyyar river in the south to Chandragiripuzha in the north. All these rivers drain and dissect the area before debouching in to the Lakshadweep Sea. Most of the major streams, upon entering the coastal plains, become meandering with very gentle gradient upto their confluence with the sea. Hence tidal effects are felt as much as 15 km upstream of their confluence, due to which all the rivers and canals in the area become brackish during the summer non-rainy periods. There are a number of criss-cross channels connecting the rivers and backwaters, thus providing a network of canals for navigation.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

1.6 Climate and rainfall The area enjoys a tropical monsoon climate with two rainy seasons between June and December and a hot summer season from January to May. The southernmost portion of the area receives an average rainfall of 1934 mm (Attingal). The rainfall increases towards north. Around Alleppey, the rainfall is 3100 mm and along the northernmost part, it is between 2900 and 3000 mm. The highest recorded rainfall is 5183.6 mm at Mavelikara during 1933 and the lowest is 991 mm at Vaikom during 1912. The southwest monsoon period is between June to September and contributes 65% of the rainfall. The northeast monsoon from October to December, though contributes- only 20%, is consiaered crucial in recharging the ground water system and also in maintaining the stream flow to last the leaner summer months. A minimum coefficient of variation of rainfall is recorded around Alleppey, i.e. 15.4%, and the coefficient of variation increases towards south and north. 1.7 Soil Coastal Alluvial soil Coastal alluvial soil are seen all along the coastal tracts and have been developed from marine and estuarine deposits. These show incipient development. The texture is dominated by sand fraction. These are excessively drained with very high permeability. The horizon is usually thin and the surface textures observed are loamy and sandy loam. The water table is high in the low lying areas. Profiles in these areas show mottling in lower layers. These soils have low fertility level. The low content of organic matter and clay has resulted in low cation exchange capacity of the soil. Greyish onattukara soil These soils are confined to Karunagapally, Karthikapally and Mavelikara taluks of Quilon and Alappuzha districts. These occur as marine deposits extending to the interior upto the laterite belt. The soils in general are coarse textured with immature profiles. These soils are excessively drained with very high permeability. The soils are acidic and have very high permeability. The soils are acidic and are extremely deficient in all the major plant nutrients. Brown hypidomorphic soils The hypidiomorphic soils as a group occur over extensive areas. These soils are mostly confined to valley bottoms of undulating topography in the upland areas and in the low lying areas of coastal strip. These exhibit wide variation in physico-chemical properties and morphological features. The development of the soil profiles has occurred under impeded drainage conditions. These soils therefore exhibit characteristic hypidiomorphic features like grey horizons, mottling streaks, hardpans, organic matter depositions, iron and manganese dioxide concretions etc. Drainage is the major problem. These are moderately supplied with organic matter, nitrogen and potassium and are deficient in lime and phosphate. Acidity is a problem in some areas. Hypidomorphic saline soil These saline soils are met within the coastal tracts of Alappuzha district. The origin, genesis and development of these soils have been under peculiar physiographic conditions. The network of backwaters and estuarines bordering the coast serve as inlet for tidal water to flow into these areas causing salinity. These soils are in general brownish deep and imperfectly drained. The profiles show wide variation in texture as is common in most of the alluvial soil.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Acid and saline soil These are characteristic soils of the Kuttanad region, and having a unique agricultural tract. A good portion of this area lies below the mean sea level and is submerged for the major part of the year. Soils of the Kuttanad form the normal well drained soils in their morphological chemical and physical characteristics. The soils of this region have been further classified into three groups. These are 1. Kayal soil. 2. Karappadam soils and 3. Kari soils. The soil map of the area is given in Fig 1.3.

Kayal soil. These are found in the reclaimed lake beds in Alappuzha district. These are very deep, poorly drained dark brown alluvial soils having silty loam to silty clay loam surface texure. The sub soil shows the presence of lime shells. The clay content usually decreases with depth. These soils are slightly acidic, medium in organic matter and poor in total and available nutreints, but are fairly rich in calcium. These are seriously affected by salinity. A whitish colour on the surface is usually observed due to accumulation of salts. Karappadam soils These occur along the inland waterways and rivers and are distributed over large part of the region. These are river borne alluvial soils occurring in nearly level or flat lands lying 1 to 2 metres below the mean sea level. These soils are very deep, poorly drained and dark grey with clay loam surface texture followed by salty clay sub soils. These soils are characterized by higher acidicity high salt content and fair amount of decaying organic matter. These are generally poor in available nutrients particularly phosphorous. These are also highly deficient in lime. Kari soils. These resemble peat soils. These occur in patches in Alappuzha area and exhibit characteristics of one sub merged forest area. These are black, poorly drained heavy textured soils distributed in flat area lying 1 to 2 metres below mean sea level. These remain submerged for nearly six month in a year. The profiles exhibit typical aquic characteristics. Decomposed organic matter is often observed in the lower layers. These soils are highly acidic in reaction the pH approaching 3.0 during summer months. Accumulation of salts to toxic level often affects the crop growth and yield in this region.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Fig 1.3. Soil types in the area

1.8 Agriculture and Irrigation Irrigation is not much practised in the area. Canal irrigation is available for paddy in parts of Kole lands and Kuttanad area. Paddy, banana and coconut are the main crops. Arecanut, vegetables and seasamom are the minor crops. Coconut and arecanut are seen mainly fringing the paddy fields and valleys. Vegetables, seasamom etc. are grown along the paddy fields as an intercrop. Kuttanad region is the ‘rice bowl' of Kerala. The wet lands of this area lie about 0.5 to 2 m below the mean sea level and remains water logged almost throughout the year, being subjected to continued flood submergence during the monsoons. Paddy is grown in these wetlands under different agronomic conditions and seasons. The wet lands are broadly classified into 'Virippu' lands and 'Punja' lands, depending upon their elevation. In the relatively higher elevated Virippu lands, two crops of paddy are grown, one during 'Virippu' (April-August) season, and the other during the 'Mundakan' (September-December) season. The wetlands, which are usually water logged and submerged for most of the time are called the 'Punja" lands. The season of cultivation is different from the usual pattern of 'Virippu' (Kharif) and 'Mundakan' (Rabi). 'Punja' season is generally the period between 'mid-rabi and mid- summer season i.e. between November and February. Generally one crop of paddy is grown on

Mapping and Management Plan of the Coastal Aquifer System of Kerala

the 'Punja' lands. Cultivation in the Punja lands is done in a special method. Temporary or semi permanent earthern bunds are constructed around the fields prepared for agricultural operations. Letting the water through sluices in these bunds carries out the periodical irrigation of paddy. The 'Punja lands' are divided into homogeneous physical entitites called "Padasekharams", which are contiguous stretches of wetlands. The 'Punja' lands account for nearly 80% of the wetlands in the Kuttanad region. The "Padasekharams" are again classified into 3 broad categories viz. the Karapadams, the Kayal lands and Karilans. The 'Karapadams' are generally situated along the water ways or constitutes the lower reaches of the eastern and southern periphery of Kuttanad, covering an area of 33,000 hectares. The fertility of these Karapadam lands is periodically replenished by the silt, deposited by the flood waters. The 'Kayal lands' having an extent of 10,000 hectares are spread over Chennamkory, Kainakary and Pulinkunnu areas of Kuttanad taluk with an elevation ranging from 1.5 to 2.5 m below the m.s.l. These are lands, which were recently reclaimed from the Vembanad lake. 1.9 Geology Coastal sands and alluvium of Recent age and sedimentary formations of Tertiary age occur all along the coastal areas. The stratigraphic sequence of the formations encountered is given in the Table 1.1 below.

Table 1.1 : Stratigraphic sequence in the study area Age Formation Lithology Recent Alluvium Sand and clay seen along the coast and the flood Quarternary plain deposits of Kuttanad and Kole lands Sub-Recent Laterite Laterite cappings on the exposed geological formations Lower Miocene Warkalai Sandstone and clays with thin bands of lignite. Lower Miocene Quilon Lime stone and clay Tertiary Oligocene to Eocene Vaikom Sandstone with pebbles and gravel beds, clay and thin bands of lignite. Eocene Alleppey Carbonacious clay and sand. Archean Crystalline Khondalite and charnockite basement rocks Tertiaries Sedimentary formations equivalent to Cucaalore and Rajahmundry sandstones of east coast was first reported by W. King (1882). There are very limited exposures of these beds and the best exposures are available in the cliff sections near Varkala. The major lithlogical units here are alternating beds of clays and sands, with thin lenticular bands of lignite. The sandstones are ferrugenous, gritty and locally clayey and the clays are usually variegated or mottled. These sandstone-clay horizons are underlain by fossiliferous calcareous formations known as Quilon beds. Best exposures of the Quilon beds are seen at S.Paravur, Padappakkara and Mayyand in Quilon district. These Tertiary formations also have undergone deep weathering and lateri- tisation which very often masks them. The Quilon limestones have been taken as the marker horizon for distinguishing the Warkalai bed at the top and the Vaikom beds at the bottom of Quilon beds. The Alleppey formation

Mapping and Management Plan of the Coastal Aquifer System of Kerala

occurring at depth has been distinguished on the basis of lithology and palynological studies of the samples carried out by Birbar Sahni Institute which conforms to Eocene age for these. 1.9.1 Regional geology and structure Studies carried out by the ONGC in the off shore areas of west coast have brought in valuable information and enables getting a regional picture of the Tertiary sediments and geological structure. This is of significance in the study of hydrogeology of the Tertiary sediments in the Kerala coast and as such is briefly mentioned. The studies in the off shore basin indicates that the sedimentary thickness increases from south to north and the maximum thickness of 4 km is observed NW of Bombay in the off shore. It is also seen that the thickness is maximum a few kilometres off the west coast and decreases towards west and east (Prasada Rao, R and Srivatsava D.C, 1984). Studies in the Kerala coast and off shore areas have indicated that; i) The deposition of the Tertiary sediments has taken place in a faulted crystalline basement, ii) The tectonics of the mainland affect upto say 45 km in the off shore, west of the coast, iii) The Kerala off shore basin is divisible into different tectonic units and comprises of different basement faults, iv) The basin fault has restricted deposition of thicker sediments west of the zone v) Miocene shelf was faulted intensely during the period of emergence of uplift. The Konkan shelf has a thick carbonate development whereas Kerala basin shows a development of arenaceous facies. There is a main basin margin fault running almost parallel to the coast in the off shore about 7 km west of Quilon, 5 km west of Alleppey and 20 km west of Cochin (Fig. 4).Two principal faults, F3 and F4 are running in NE-SW direction of which F3 is running across in the Kerala coastal area. A deep seated fault in the carystalline basement passing through Quilon, east of Alleppey, trending NW to SE is disturbedby: E-W faults (Balakrishnan T.S. and Sharma D.S., 1981).

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Fig 1.4: Tectonic map of Kerala coast and off shore (Prasada Rao,1984) The Photogeological and Remote Sensing studies indicated that the sediments were deposited in a faulted basement. It is inferred that there could have been later horizontal movements along the existing weak planes which brought thicker sediments by the side of the thinner ones. Moreoever, the basin was a sinking one with sediment load. The Tertiary formations of this area are stillunconsolidated and hence small movements afterwards if any have not affected the sediments.A brief description of the four Tertiary beds and of recent sediments is given:

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Warkalai beds These form the youngest formation of the Tertiary sediments of Kerala. Exposures of these are mostly eroded and are mostly capped by laterites. Typical outcrops are seen along the cliff section. Best exposures of this sequence are seen in the cliff sections of Varkala beach which forms the type area. The beds dip towards east/ northwest. These attain a maximum thickness of 140 m around Alleppey. These are made up of alternate layers of fine to medium grained sand with clays and thin bands of lignite. The age of Warkalai beds was considered to be upper Miocene (M.S. Krishnan, 1982). K.M. Nair and M.R. Rao (1988) consider the age of this formation as lower Miocene. Samples collected from this horizon were dated as lower-Miocene by the Birbal Sahni Institute of Paleobotany based on the palynological evidence. The underlying Quilon formation was dated as Burdigalian age. Hence, it is inferred that the Warkalai might have been deposited during the upper half of lower-Miocene. Quilon beds Underlying the Warkalai beds there is a horizon of hard, compact and ash grey limestone, calcareous clay and marl. These are often associated with fine to medium sand and are generally seen south of Cochin upto Edavai and along the major portion of the Kuttanad area. These are exposed in the steep slopes bordering the Ashtamudy lake at Padappakara near Quilon and form the type area. Exposures are seen near Paravur, south of Quilon town, and also in shallow dug well zone around Mayyanad near Quilon. The beds are often lateritised along the outcrops. The thickness of this formation varies from 6 to 100 metres with the maximum thickness at Nirkunnam near Ambalapuzha. The Quilon beds have been assigned Burdigalian age, based on micro fossil studies. Vaikom beds These beds were not known till recently and these were first considered as part of Warkalai. These beds were first encountered in the boreholes drilled by CGWB in parts of Alleppey and Ernakulam districts. On a detailed study, these were found to underlie the Quilon beds and extend almost over the entire sedimentary basin. Best exposures are seen southeast of Vaikom and are termed as Vaikom beds (Raghava Rao et al, 1976). The exposures of these beds are lateritised and perhaps all the lateritised sediments seen along the upland portion constitute Vaikom beds.The pebble beds reported around Kurichi, Kallara area of Kottayam district (S.D. Pawar et al, 1980-81) belong to this formation. Alleppey beds A horizon composed of highly carbonaceous clay and sandy clay has been encountered in the deeper boreholes drilled between Arthungal and Nallanickal. This formation is distinctly different from that of the overlying Vaikom beds in their lithlogical characters and can be easily identified in the borehole samples and electrical logs. The palynological studies carried out by the Birbal Sahni Institute have reported a rich polynological assemblage which confirms to Eocene age. Since these beds are found in the deeper boreholes in and around Alleppey, these were termed Alleppey beds. None of the boreholes drilled in this section has pierced through the entire thickness of these beds and as such the thickness is not known. Tertiary Laterite All the Tertiary sediments are found to be lateritised on the top indicating an emergence or sea level change. Due to this laterite capping demarcating the individual outcrops of different

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Tertiary beds is difficult. The thickness of the laterite beds goes upto 30 m. in these along the surface whereas upto 74 m thicknesses were encountered in some of the boreholes. The laterite forms a definite geological horizon in the sedimentary sequence in the coastal area. It is found that at places the laterites have been eroded totally before the deposition of the recent alluvium. The laterites capping the Teriary beds are considered as part of Tertiary sediments and it does not form an aquifer. Recent Sediments The alluvial beds in the area is represented by back water and lagoonal deposits brought down by the west flowing rivers. These deposits comprise of pure white quartz sands, dirty white silt and silty sand, grey to dark grey beach sands, red teri sands and black clay. These deposits along the beach get reworked by the waves and tides. These are unconsolidated sediments, the thickness of which varies from few metres to more than 100 m around Alleppey. Buried forest covers are reported in parts of Kuttanad area between Ambalapuzha and pallipad (S.D. Pawar et al, 1980). The absence of Delta in any river mouth is surprising and this is possibly due to structural disturbances. However, the low lying Kuttanad area forms the deltaic region for Pamba, Meenachil and Muvattupuzha rivers. Paleoclimate and environment of deposition of Tertiary sediments. The studies of the pollen grains indicate a humid tropical climate with abundant rainfall. Exposure of brackish mangrove swamps are indicated by the presence of pollen grains of Barringtima ano Nipa. Presence of pollen types referable to pocamongetaneous and Halorgaceae highlights the presence of fresh water lakes or ponds dotting the landscape away from the mangrove belt towards inland (M.R. Rao, 1988). The presence of lignite and grain size characteristics indicates a continental deposition for warkalai beds. A shallow marine quite water environment of deposition of Quilon beds is indicated by the abundance of calcareous material with clay, shells and coral reef. Coarse sand to granular lignite, pebble beds point to a shallow continual deposition for Vaikom beds.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

2.0 DATA COLLECTION, GENERATION AND INTEGRATION The data gaps were identified from detailed analysis of existing data available with CGWB and other State departments. New data has been generated in the data gaps through various activities such as establishment of water level monitoring wells, water quality monitoring wells, geophysical investigations and aquifer evaluation. The status of data on various themes after data collection, generation and integration is given in Table 2.1. Ground water in the area occurs under phreatic conditions in the Recent sediments and under both phreatic and confined conditions in the Tertiary sediments. The value addition made after data collection, generation and integration of various components of the groundwater regime are described in the following sections.

Table 2.1 Status of data collection, generation and integration Phreatic aquifer Tertiary aquifers

Themes enerated enerated

quirement quirement Existing data Data G Total Additional Data re Existing data Data G Total Additional Data re Dugwells 388 225 613 nil - - - nil

Exploratory wells 20 0 20 nil 188 0 188 nil

Piezometers 26 0 26 nil 19 0 19 25

VES/logging 20 0 20 nil 316 24 340 nil

Water quality 128 25 153 340 30 60 90 60

Soil Infiltration Nil 25 25 0 - - - nil

Pumping tests 9 19 28 nil 35 0 35 19

2.1 Phreatic aquifer system The data on groundwater regime such as climate, soil, geomorphology, geology, drainage were collected from concerned state and central government departments. The climatic data from IMD station and the rainfall data from eight rain gauge stations having influence over the area were used. The information on soil types of the area were collected from the soil conservation department, Govt. of Kerala and from the published of reports of CGWB. The information on geomorphology is collected from the available literature and from the geomorphology map

Mapping and Management Plan of the Coastal Aquifer System of Kerala

prepared by the Land Use Board, Govt, of kerala. The Land Use Board has prepared toposheet wise geomorphology in 1:50000 scale. Based on this information the geomorphology of the area has been defined and the geomorphology map prepared. The drainage data from State Land Use Board has been used in the study and no data on drainage has been generated in the present study. The data water level, geophysics, lithology and water quality were collected from CGWB and State Ground Water Department have been integrated additional data generated based on the availability and is given in Table 2.1. 2.2 Tertiary aquifer system The data on VES, geophysical logging, lithology, water quality and isotopes were collected and integrated. Generation of additional data on lithology, aquifer characteristics and piezometric head from 25 piezometers are projected in the study. About 60 water sampling is also projected under data generation.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

3.0 DATA INTERPRETATION AND AQUIFER MAPPING 3.1 Aquifer geometry The geological sections prepared along the coast between Anjengo and Pariyapuram shows (Fig. 3.1) a maximum thickness of Recent Alluvium at Kattur which is in the order of 100 m.

Fig 3.1: The geological sections along the coast between Anjengo and Pariyapuram The lateral extent of alluvium is prominent in Alappuzha and Kollam districts and the panel diagram in Fig 3.2 gives a better picture on the lateral and vertical distribution of various litho units in the coastal sediments. The panel diagram shows both lateral and vertical variation in aquifer thickness. The top and middle granular zones in the panel diagram represent the Recent alluvium and the bottom one represents part of the Tertiary aquifer. The laterite bed demarcating the Recent beds from Tertiary beds is almost eroded and its remnants are seen at Mundur and Koduthuruthy. The granular zones in Recent alluvium pinches out towards east but having continuity towards south and south east direction. Also, the lateral variation in granularity and bed thickness is noticeable. Another important aspect noticeable is that the bottom granular zone in the alluvium is under confined conditions by a thick confining clay layer.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Fig. 3.2 Panel diagram showing aquifer disposition in Kuttanad alluvium

3.2 Composite lithologs and VES The electrical logging data from the exploratory boreholes in the area has been utilized in the present study for inferring the geoelectric characteristics of various litho units and the disposition of granular zones in the alluvium. The geophysical logs were analysed to understand the hydrostratigraphy of the shallow unconsolidated sediments and variations in the quality of the formation waters. In all 21 geophysical logs from shallow bore wells in parts of Alleppey, Kotayam and Pathanamthitta districts were analysed and the wells have a maximum depth of 60 m. Preliminary analysis of the geophysical logs infers that the eastern part of the area around the sites Mundar, Kudavechur, Mulakkanthuruthy (9-11m.), Thalavadi, Podiyadi, Pandanadu (0- 6m.), Elanjimale, Mamprapadam and Mavelikara, fresh water zones occur at different depths ranges. However, in the western part of the area in most of the boreholes groundwater as expected to be saline / brackish nature throughout the depth drilled except at Tagazhi (below 30m.) and at Kelamangalam (below 16m.). Below 20m depth, most of the boreholes are showing high natural gamma radiation at the granular zones indicating the enrichment of radioactive minerals.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

The composite logs of six bore holes at Valiyathera, Cheruvaranam, Muhama, Thottapally, Karuvatta and Melpadam are given in Figs 3.3 and 3.4. The geoelectrical characteristics of the formation can be inferred from the pattern of SP, resistivity and gamma logs and in comparison with the litholog. . High resistivity, high negative SP and low radiation counts of gamma for the granular zones and vice versa for the clay layers are expected in a formation with fresh water.With quality change in water from fresh to brackish the conductivity of formation increases and is reflected accordingly in the electrical logs but no way affects the gamma log. Hence, gamma logs helps in identifying granular zones irrespective of its water quality.

Fig.3.3 Composite logs of Lithology, SP, Resistivity and Natural Gamma

Fig.3.4. Composite logs of lithology, SP, Resistivity and Natural Gamma

Mapping and Management Plan of the Coastal Aquifer System of Kerala

From these logs it can be observed that after certain depth the radiation counts are higher for the granular zones compared to that of clay layers, which is an abnormality. The presence of monazite, a mineral of thorium, in the granular zones at certain depth is responsible for this anomaly. It indicates the enrichment of monazite during certain period in the depositional history. It is quite possible that the granular zones may be misinterpreted as clay layers unless it is properly compared and studied with other electrical logs. The depth of occurrence of high gamma counts in granular zones varies from place to place. For example, at Valiathara and Muhama the depth of occurrence of high gamma counts in granular zones starts at 33m and 45 m respectively. Similarly for Thottapally, Karuvatta and Melpadam it is at 37 m, 25 m and 20 m respectively. The depth of granular zones where high gamma counts are noticed from the gamma logs of 21 wells is given in Table 3.1. These sands with relatively high monazite might have deposited at different cycles of marine transgression and regression. The depth of granular zones with radioactive sands varies from 12 to 45 m and the maximum depth is observed near Vembanad lake.

Table 3.1 Depth of granular zones where high gamma count noticed

Sl.No Borehole location Longitude Latitude Depth of occurrence of sand beds with high gamma count

1 Valiathara 76.321 9.741 33 2 Mundur 76.488 9.726 18 3 Cheruvaranam 76.362 9.651 30 4 Kudavechur 76.418 9.673 34 5 Koduthuruthi 76.492 9.689 18 6 Muhamma 76.367 9.615 45 7 Kumarakom 76.438 9.598 35 8 Pandarakalam 76.379 9.474 28 9 Neelamperur 76.515 9.515 17 10 Mulakkanthuruthy 76.537 9.498 13 11 Thakazhi 76.402 9.375 16 12 Kelamangalam 76.426 9.371 24 13 Thalavadi 76.512 9.382 12 14 Podiyadi 76.553 9.381 16 15 Purakkad 76.382 9.348 39 16 Thottappalli 76.388 9.32 37 17 Karuvatta 76.439 9.319 25 18 Melpadam 76.51 9.321 20 19 Pandanad 76.59 9.332 16 20 Elanjimel 76.601 9.276 17 21 Mamprapadam 76.602 9.261 15 Vertical Electrical Soundings (VES) The VES carried out near to the coast at about 11 sites namely Karipuzha, Kuttitheravu, Krishnapuram, Puthiyakavu, Tazhavu, Kuttivattom, Chavara, Thekkumbagam, Thiruvallavaram, Kollam and Pozhikkara indicated first and/or second layer resisitvity in the range of 200-3000

Mapping and Management Plan of the Coastal Aquifer System of Kerala

ohm.m with thickness in the range of 1.2-15 m. which is alluvium. At Puthiyakavu, Thazhavu, Thiruvallavaram and Pozhikkara the alluvial formation layer is followed by the formation with resistivity of 50-130 ohm.m which is sand with clay content. The thickness of this formation varies from 4.5m to extending in nature. The formation with resistivity of 11-85ohm.m was recorded at the sites with thickness in the range of 29m to extending in nature which is clay to alternate layers of clay and sand. The depth to hard lime stone was encountered at three sites namely Krishnapuram, Kollam and Chavara which is in the range of 40-55m. In Krishnapuram the hard formation was extending up to 120m where as at Chavara and Kollam it was extending up to 100 and 150 m. A total of 19 VES were carried out in tertiary formation. The interpreted results indicated that the depth to massive formation was encountered at only two sites where it was 48 m and 120 m respectively. At only one site namely Ashtamudiseri the top soil which is clayey in nature has recorded resistivity of 50 ohm.m. The resistivity of 5 ohm.m was recorded after 10m depth which indicates salinity of the formation due to adjacent back water. At the remaining sites the first layer resistivity was varying in therange of 330-3500 ohm.m which is soil to lateritic soil. The thickness of this formation is varying in the range of 1.2-12m. At about 10 sites the second layer resistivity was varying in the range of 200-800 ohm.m which indicates sand to laterite in nature. The thickness of this formation is varying in the range of 3.5-24.8m. At the remaining sites the resistivity of this layer is varying in the range of 40-150 ohm.m which indicates clay to sandy clay with intermitant sand. The thickness of this formation is varying in the range of 5-48 m except at one site where it was extending in nature. At about 10 sites the third layer (at one place third and fourth layers) resistivity was varying in the range of 20-80 ohm.m which indicates alternate layers of clay and sand. In this range the lower order of resistivities indicate more of clay content where as higher order of resistivities indicates more of sandy nature. The exact thickness of sand and clay could not be detected and separated due to the limitations of the method.The thickness of this formation is extending in nature except at two sites where it was 28 and 34m respectively. At about 8 sites the second and/or third layer resistivity was varying in the range of 120-450 ohm.m which indicates sand to hard sand stone. The thickness of this formation was extending in nature (thickness of 25-172m.). The geophysical surveys carried out at 10 sites indicated the hard rock nature of the formation. At these sites only at three no. of sites the depth to massive formation was encountered which is in the range of 70-150 ohm.m. At the remaining 7 no of sites the last layer was extending with depth. The resistivity of the first layer was varying in the range of 220-4800 ohm.m with thickness in the range of 1.5-6 m. which is soil to lateritic soil in nature. At two sites the second layer resistivity was varying around 600 and 750 ohm.m which is also considered as laterite to hard formation in nature with thickness of 6.5 and7 m respectively. At Mavady, Pandalam, Ezhukone, Oyoor and Navaikulam the second and/or third layer recorded resistivity of 34-150 ohm.m which is weathered formation. This formation along with soil extends to a depth range of 18-28 m. At about 7 sites namely Adoor, Mavady, Thumpanam, Padalam, Ezhukone, Oyoor and Navaikulam the third and fourth layer recorded resistivity in the range of 100-300 ohm.m which is expected to be fractured in nature. At Enathu, Nellikunnam and Cheriyavelunalloor the third layer resistivity was varying in the range of 450-690 ohm.m which is devoid of any fractures. The aquifer I which consists of soil and weathered formation thickness was varying uin the range of 5-28 m. The aquifer II which consists of hard, massive and fractured formation thickness was varying in the range of 96-182 m.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

The geophysical surveys carried out in the study area was analysed in alignments from west to east indicated the following. In the first alignment the geophysical surveys carried out from west to east at the places Kuttitheruvu, Kattanam, Charummood, Noornad, Adukattikulangara and Adoor indicated increase in resistivity of third layer from 25 ohm.m near the coast to 300 ohm.m away from the coast indicating the decrease in clay content away from the coast. In between Adikattukulangara and Adoor the transition from tertiary formation to hard rock takes place. In the second alignment the geophysical surveys carried out west to east at Puthiyakavu, Thazhavu, Chakkuvalli, Kadambanad and Enathu indicated that near to the coast the resistivity at depth varies in the range of 26-50 ohm.m indicating the clayey nature where as in central part it was in the range of 150-255 ohm.m and is free from clay. The formation changes from tertiary to hard rock in between Kadambanad and Enathu. In the third alignment the surveys carried out from west to east at Thekkumbagam, Asthamudiseri, Perinod, Kundara, Ezhikone and Nellikunnam. The interpreted results at Ashtamudiseri indicated very low resistivity of 5 ohm.m due to back waters.The results also indicated that from west to east the resistivity at depth increases from 48 ohm.m to 470 ohm.m indicating resistivity increase as moving from coast to away.The formation changes from tertiary to hard rock inbetween Kundara to Ezhukone. In the fourth alignment the surveys carried out from west to east at Thiruvallavaram, Kollam, Mukhatala, Kannanalloor, Adichanalloor, Oyoor and Cheriyavelunalloor indicated the resistivity value at depth increased from Kollam to Cheriyavelunalloor in the range of 45-690 ohm.m except at Kannanallor where it was shown resistivity value of 450 ohm.m. The last two easteren side locations of Oyoor and Cheriyavelunalloor falls in hard rock area. In the fifth alignment the surveys carried out at Pozhikkara, Pudakulam, Meenambalam and Parippalli from west to east indicated at Pozhikkara near to the coast the resistivity value is around 11 ohm.m which indicates clayey content of the formation. The resistivity values at depth is higher at Pudukulam and Parippalli which is in the range of 115-270 ohm.m indicates the sand stone formation. At Meenambalam the resistivity at depth was around 30 ohm.m which indicates clayey sand. 3.3 Soil Infiltration Studies Infiltration rate is the velocity or speed at which water enters into the soil. It is usually measured by the depth (in mm) of the water layer that can enter the soil in one hour. An infiltration rate of 15 mm/hour means that a water layer of 15 mm on the soil surface will take one hour to infiltrate. In dry soil, water infiltrates rapidly. This is called the initial infiltrationrate. As more water replaces the air in the pores, the water from the soil surface infiltrates more slowly and eventually reaches a steady rate. This is called the basic infiltration rate. The infiltration rate depends on soil texture and soil structure. The most common method to measure the infiltration rate is by a field test using a double ring infiltrometer. The basic infiltration rates for various soil types are shown below.

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Four field infiltration tests were conducted in the coastal sedimets in Alleppey area and the infiltration rate varies from 6 to 32 cm/hour (Table 3.2).

Table 3.2 Soil Infiltration test results Sl. District Test site Type of soil Rate of No. infiltration in cm/hour 1 Kottayam Govt.LP School, Perunna, Near Partially 31.5 NSS College, Changanasery compacted sand 2 Alapuzha Fathima Matha Gravel sand 15.0 Church,Pallikuttumma compacted ,Ramankari on Alappuzha- Changanasery Road. 3 Alapuzha Govt.LP School Kunnamkary Clay loam 6.0 Veliyanad Panchayat, Alappuzha 4 Pathanamthitta CMS School Play Ground Sandy loam 18.0 Thiruvalla 3.4. Phreatic aquifers: The Recent sediments comprising of coastal sands and alluvium of flood plain deposits extend all along the coast and much interior in the Kuttanad and Kole lands area. This forms the most potential phreatic aquifer and has been extensively developed through a large number of dug wells to meet the domestic needs, and to a limited extent for irrigation and industrial needs. 3.4.1Water level A total number of 613 monitoring wells were established in the area for periodical monitoring of water levels during four seasons viz; January, April, August and November. The water levels monitored during April and November are the pre-monsoon and post- monsoon data respectively. From the study of the data and hydrographs, it is observed that there are two periods in a year viz. recession and recharge. The stabilisation in the recession is observed to commence after the attainment of peak water level during southwest monsoon, period from June to September. The contribution from northeast monsoon is a critical factor in sustaining the system. The actual recession period commences in December and continues till the onset of southwest monsoon in June. The recharge period commences from June. The long term changes in water levels are studied from the Ground Water Monitoring Stations (GWMS) maintained by CGWB in the area and the static data of which is given in Appendix 1. The water levels recorded in the observation wells during pre-monsoon (April) and post- monsoon periods (November) are shown in Appendix 2. This data has been used to prepare maps showing the distribution of groundwater levels. The water levels in major part of the area are <4.0 m bgl during pre-monsoon period and < 2.0 m bgl. during post- monsoon period. A perusal of water level data shows water levels below 2m in 65% of the monitoring wells in April and 84% of the wells in November. The average water level during pre-monsoon is 1.99m and that during post-monsoon period is 1.47m. Thus shallow water conditions are prevailing in a major part of the area. The seasonal water level fluctuations in an area are computed as the difference between the water levels recorded during the pre- and post-monsoon periods. A surplus groundwater recharge

Mapping and Management Plan of the Coastal Aquifer System of Kerala

is indicated by a rise in water level during post-monsoon period when compared to the pre- monsoon period. Whereas, inadequate compensation of groundwater draft by the monsoon and other recharge components is indicated by a fall in water level..The water level fluctuation in the southern parts of Vamanapuram, Ithikkara ano Kallada basins is in the range of 1.00 to 2.00 metres, whereas in the central part of Pamba basin it is of the order of 0.50 to 2.00 metres. In the Meenachil, Muvattupuzha, Periyar and Chalakudy basins, the fluctuation ranges from 1.00 to 2.00 metres. In the northern part of coastal area in the Kole lands, Ponnani and Kadalundi basins, the range of fluctuation recorded is of the order of 1.0 to 4.0 m. 3.4.2 Groundwater level fluctuations on a decadal scale (2004-2013) The variation in water level with reference to time and space is the net result of groundwater development and recharge. The long term change in water level is discernible from the trend of water levels over a period of time and is best reflected in a hydrograph. Salient details of water level trends during pre- and post-monsoon seasons for a period of 10 years are furnished in Table 3.3. Table. 3.3 Trend of Pre- and Post-monsoon water levels in the study area

Sl No. Location Pre-monsoon Trend (m/year) Post-monsoon Trend (m/year)

1 Alleppey -0.01 -0.01 2 Aranootimangalam 0.14 -0.10 3 Arukutti -0.07 0.04 4 Chettikulangara -0.05 0.01 5 Edathua -0.08 -0.01 6 Ezhupunna -0.04 0.01 7 Haripad -0.08 0.03 8 Idakunnam -0.18 -0.05 9 Kallissery -0.02 0.07 10 Kandiyoor 0.00 0.04 11 Karumady -0.09 -0.02 12 Karuvatta 0.10 0.01 13 Kattanam -0.02 -0.06 14 Kattoor -0.07 0.06 15 Kayamkulam 0.03 0.00 16 Kuzhamathu -0.02 -0.11 17 Mannar 0.07 0.01 18 Mavelikara 0.02 0.03 19 Mudhukulam 0.05 -0.05 20 Muttam -0.03 0.01 21 Nedumudi 0.09 0.02 22 Nooranad 0.22 -0.14 23 Pacha 0.03 0.01 24 Pallarimangalam 0.02 -0.01 25 Parumala -0.04 -0.20 26 Pattanakad 0.02 0.03 27 Purakkad -0.01 -0.06 28 Ramankari -0.03 -0.01 29 Thakazhi 0.00 -0.05 30 Thamarakulam -0.10 -0.03 31 Thevery -0.04 0.04 32 Thuravur -0.04 0.03 33 Trikkunnapuzha 0.01 -0.01 34 Valavanad -0.03 0.02 35 Vallikunnam -0.11 0.27 36 Kumarakom -0.07 -0.01 37 Tiruvarpu 0.11 0.09 38 Vechur 0.01 0.07

Mapping and Management Plan of the Coastal Aquifer System of Kerala

A perusal of the analysed data on water level trends shows no significant decrease in water levels. Water level trend (Fig 3.5) in some of the wells shows a slightly rising trend, perhaps due to less development of the water table aquifer. Majority of dug wells in Kuttanad area are tapping Phreatic aquifer and the corresponding hydrographs indicate a slight rising trend in water level over a period of 30 years. The behaviour of ground water inphreatic aquifer of weathered formation is falling in Premonsoon period as observed in Changanacherry.

Fig.3.5 Hydrographs of dug wells in the study area

The piezometers taping the Tertiary aquifers at present are insufficient to create ameaningful contour map useful in quantifying the flow in the system. Most of thepiezometers constructed earlier are defunct due to corrosion of pipes or destroyed. The piezometric contour map based on 1985 data showed a North to NNW flowdirection in the Tertiary aquifers. Because of the heavy draft in Alleppey town area,there the flow is from all the directions as observed in the present map and the generalNNW direction of flow is inconspicuous in Kuttanad area. Depth to water level maps Based on Water Level data on NHS wells the premonsoon and postmonsoon maps were prepared and shown in Fig 3.6 below. During premonsoon period, shallow water level is predominantly observed in the western side and around Vembanad lake. Major area represents water level in the range of 2-5 m bgl. Water level in the range of 5-10 m bgl is visible in the western part and dominant in the southern part. Deeper water level in the range of 10-20 m bgl is seen as patches

Mapping and Management Plan of the Coastal Aquifer System of Kerala

in the western part and southern part. In general water level is getting deeper while travelling from north to south and also west to east. During Post monsoon shallow water level in the range of 0-2 m bgl is present in the area and even extended upto eastern boundary at certain places. Genarally southern area is deeper compared to northern side. The water level starts from 5 to >20 m bgl range. In area around Kundara the water level is deeper of >20 m bgl due to mining activities in selected pockets. In north side the water level is controlled by Vembanad lake and in south it is by Sasthamkotta lake and the thick laterite pile.The average water level during pre-monsoon is 0.9 m and thatduring post-monsoon period is 0.6m. Thus shallow water conditions are prevailing in a major part of the area.

Fig.3.6 Depth to water level map during Premonsoon (April 2014 )and Postmonsoon (November 2014)

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Fig.3.7 Water level fluctuation with respect to decadal mean during Prempnsoon (April 2014) and Postmonsoon (November 2014) In premonsoon period major part of the area is showing a falling trend in the range of 0-2 m bgl and the fall in the range of 2-4 m bgl is visible in isolated pockets as shown in Fig 3.7. Rise in water level is observed in central and southern part.In Kayamkulam-Mavelikara belt the rise in water level is continuous from west to east.Water level is predominantly falling in the range of 0-2 m bgl in Post monsoon period. Rise in water level is visible in isolated pockets like Cherthala,Haripad, and eastern boerder in and around Kottayam and Kaduthuruthy. 3.4.3 Yield of wells tapping the phreatic aquifer Dug wells and filter points are suitable structures for the phreatic zone. The central part of the area has thick sediments up to 80m and sustains tube wells of high yield up to 60000 litres per day. The depth of the wells ranges from 2.75 to 10.6 m bgl and at places, where the saturated sand thickness exceeds 5 m, filter point wells are found to be promising. Potential areas for filter point wells are around Iravipuram, Chavara, Kayamkulam, Alleppey, Shertallai, Vypin, Ponnani and Tirur. The discharge from these wells range from 2.76 to 4.16 lps and are pumped for 5 to 8 hours a day. The yield of the shallow dug wells is in the range 15,000 to 20,000 litres per day. Quilon and Vaikom beds are invariably lateritised at the top and the laterites extend to considerable depth. Ground water occurs under phreatic conditions in the laterites capping the seaiments. By virtue of its high porosity, the laterites get filled up by the first few showers and due to the same porous nature, the ground water drains off immediately after the rains. The

Mapping and Management Plan of the Coastal Aquifer System of Kerala

laterite cappings seen along the eastern peripheral area of the sedimentary basin are the recharge area for the Tertiary aquifers. The water level is generally deep and ranges from 3 to 30 m bgl. The wells tapping this in the elevated portion get almost dry. The specific capacity of the wells ranges from 11.5 to 12.63 lpm/m. The laboratory tests give permeability between 7.2 x 10-6 to 1.9 x 10-5 m/sec, the average being 7.39 x 10-5 m/sec. 3.5. Deep confined aquifers The semi consolidated Tertiary sediments form potential confined aquifers and has been developed to a limited extent by tubewells. The Central Ground Water Board carried out about 64 exploratory drilling in these areas in the last few decades. The Kerala Water Authority has also drilled a larger number of shallow tubewells for water supply to rural and urban population in the coastal areas. While valuable information could be gathered about the potentialities of the aquifers, most of the tubewells constructed during earlier years have been multi-aquifer wells. To gather information on the hydraulic properties of individual aquifers, the hydro static heads from piezometers and the pumping test data from the exploratory wells were utilizes and details of piezometers are given in Appendix 3. Vertical and lateral extension of the geological formations The lithological data of 15 bore holes have been used to prepare the panel diagram (Fig 3.8) to bring out the vertical and lateral extension of the geological formations which is needed to define the aquifer geometry in the area. The sedimentary basin along the west coast is deep and has a thick pile of sediments whereas towards east it is deposited over basement at shallow depths. A 3D model of the central part of the area depicts the thickness variations in the stratigraphic sequence (Fig 3.9). The Top and bottom boundaries and thickness of geological formations derived from the litho-log is shown if Table 3.4. The information on the sub surface geology could be refined with more geological sections along select section lines (Fig.3.10) and panel diagrams (Fig. 3.11).

Fig 3.8 Panel diagram of vertical succession of geological formations in the Kuttanad area (present study)

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Fig 3.9 Sedimentary bed thickness variations in the stratigraphic sequence

Mapping and Management Plan of the Coastal Aquifer System of Kerala

Table 3.4. The Top and bottom boundaries and thickness of geological formations in different stratigraphic sequences derived from bore well data Sl. Warkali bed Quilon bed Vaikom bed Latitud Longitud N Location name Depth e e Top Bottom Thic Top Bottom Thic Top of Bottom Thic o of bed of bed knes of bed of bed knes bed m of bed knes 1 Karuvatta 428 9.3167 76.4125 61 165 104 165 229 64 229 468 239

2 Thottapalli 269.44 9.3153 76.3897 85 196 111 196 269 73 _ _ 0 3 Nirkunnam 601 9.3917 76.3667 66 203 137 203 318 115 318 510 192 4 Kalarcode 601 9.4583 76.3333 62 217 155 217 323 106 323 494 171 5 Ariyad 400 9.5375 76.3292 57 188 131 188 259 71 259 396 137 6 Kattur 504 9.5750 76.3036 99 202 103 202 271 69 271 418 147 7 Arthungal 445 9.6589 76.2997 60 156 96 156 231 75 _ _ 0 8 Cherthala 221 9.7550 76.3194 47 86 39 86 164 78 164 218 54 9 Mannanchery 203 9.5806 76.3653 56 105 49 105 121 16 121 199 78 10 Mankombu 259 9.4417 76.4222 35 92 57 92 140 48 140 258 118 11 Thrikunnapuzha 600 9.2667 76.4083 112 190 78 190 283 93 283 520 237

12 Kidangara 97 9.4194 76.4972 _ _ 0 _ _ 0 42 97 55 13 Pulikeezhu 70 9.4333 76.5439 _ _ 0 _ _ 0 38 70 32 14 Kandiyur 133 9.1714 76.5439 12 24 12 24 57 33 57 129 72 15 Muttom 275 9.2486 76.4903 20 68 48 68 102 34 102 248 146

Fig. 3.10.The vertical and lateral variation in lithology along the select section lines.

Fig.3.11 Panel diagram showing lateral and vertical variation in lithology The fence diagram shows both lateral and verticalextension and the variation in aquifer thickness.Here the recent alluvium is predominant in the western part and the thickness is gradually increasing while going from south to north.All the tertiary aquifers and recent alluvium are lying over hard rock basement which is dipping towards west. Thelaterite bed demarcating the Recent alluvium from Tertiary beds is almost eroded and itsremnants are seen at eastern

boundary area. Recentalluvium pinches out towards east but continuity is seen in south and southeast directions.The width and continuity of Warkalai and vaikom aquifers are the noticeable feature. The vaikom Aquifer is more extensive than warkalai aquifers in terms of area and thickness.Vaikom extends from west to east upto basement rocks whereas Warkalai is gradually tapering at the middle of the area towards east. 3.6. Warkalai beds This is the most extensively developed aquifer among the Tertiary group. These form semi- confined to confined aquifers. The warkalai beds contain a number of granular zones and the combined thickness of granular zones varies from 5 to 40 m The isopch of warkalai beds shows a gradual increase in bed thickness towards west (Fig.3.12). The piezometer head was 2.8 m above msl along the east (Kandiyoor) and 10 m below msl around Alleppey during 1980s. This aquifer is extensively developed for the Alleppey town water supply and rural water supply of Kuttanad area. The Warkalai aquifers are mostly composed ofmedium to fine grained sand with an effective grain size of 0.21 to 0.3 mm. From the hydrograph of Warkalai aquifer at Karthikapalli site for the period May 1986 to May 1987it is observed that the piezometric level during June to August rests around 3.90 m bgl whereas during the pre-monsoon time (January to May) the level declines to 4.70 m bgl, thus showing a fluction of 0.8 m in the piezometric head. However, a maximum fluctuation of 2.78 m is observed in the Warkalai aquifer tapped all over the area. The long term trend in water levels and piezometric heads are derived from the long term data collected over a period of time. The water level trend for the last one decade in the phreatic aquifers and for the last three decades in the tertiary aquifers has been analysed. The transmissivity value ranges between 130 and 711.61 m /day. It is minimum around Quilon and eastern areas andmaximum between Karunagapalli and Alleppey. The hydraulic conductivity ranges between 6.67 and 33.89 m/day and is maximum along the central portion of the basin. The storativity ranges from 0.00098 to 0.423. The tubewell at Thottapally has shown a negative boundary during pump test and this is possibly due to the heavy draft in Alleppey and suburbs or a clay layer or a shift in bed due to minor dislocation. The specific capacity of the tubewells ranges between 22 to 561.98 lpm/m. The summarised data of wells tested tapping the Warkalai aquifers is given in Table 3.5.

Fig. 3.12 Isopach of Warkalai beds

Table 3.5. Summarised data of wells tested tapping the Warkalai aquifers Well Location Discharge Duration of Drawdown Specific Transmissivity Storativity 3 no m /day pumping in Capacity in m2/day minutes m 1 Tirumulla- 11.88 1000 8.85 22.37 131. varam 2 Karthikapalli 22.68 1470 3.86 97.92 712 3 Muttom 54.00 600 4.33 207.85 2 96 4 Thottapalli 493.56 3000 5.26 156.38 410 3.9x10-3 5 Mankombu 25.40 i§00 2.52 168.00 2 79 6 Arthungal 100.17 1000 5.63 119.14 221

The Warkalai aquifer is extensively developed through tubewells in the areas around Alleppey town and in the adjoining Kuttanad area to meet the urban water supply scheme for Alleppey town and the rural water schemes for Kuttanad area. There are a total of 55 tubewells in operation in these areas. In Alleppey town there are a total of 31 tubewells, out of which 19 wells are being used presently. These wells are pumped continuously for 20 to 22 hours a day and the annual draft from these wells is 8 MCM. The wells in the town are closely spaced and observations made during the field studies indicate that there is mutual interference. In the Kuttanad area there are 47 tubewells of which 36 wells are in use. The annual draft from these wells is 11 MCM. Due to concentration of pumping wells in the Kuttanad Alleppey area and of wells located at closespacings of 15 to 30 metres in Alleppey town, there is mutual interference and the water levels have gone down to 10 m below mean sea level in Alleppey. 3.7 Quilon beds The hydrogeological parameters of this aquifer available are meagre. A few tubewells around Quilon tap this along with Vaikom. Data available indicate that the granular zones are meagre and do not offer promise fordevelopment. Only one piezometer was constructed in this formation at Karthikapalli. The thickness of the granularzone is between 6 and 100 metres and is composed of finer sand of size 0.17 to 0.20 mm. The piezometer head is between 1.0 and 4.0 m above msl as seen in three stations. Only one pump test was carried out in the formation andtransmissivity and hydraulic conductivity are found to be 28.22 m2 /day and 1.09 m/day respectively. 3.8 Vaikom beds The Vaikom beds, due to their coarse grained nature, form the most potential aquifer in the area. The effective grain size sands in Vaikom aquifers is between 0.13 and 0.78 and the coefficient of uniformity varies from 1.75 to 10. The granular zones constitute about 50% of the total sediments. The thickness of granular zones in this aquifer ranges from 15 to 65 metres and the yield of the wells in this formation ranges from 0.73 to 26.82 lps. The isopach of Vaikom beds (Fig. 3.13) shows a increase in thickness towards west and decreases towards north and south.

The piezometric surface ranges from 18 m above msl around Poruvazhi-Pallikal area in Quilon district and it slowly reduces towards north and west.In and around Karumadi area it is 4.8 m above msl and very slowly reaches 1.0 m. above msl around Cochin. Around Quilon the piezometric surface is 5 m below msl and at Nallanickal it is near msl (Fig, 13). The piezometric surface shows a sag in and around Kuttanad area and north where it is 1.0 m above msl. There are about 9 pumping tubewells augmenting the Quilon urban water supply and several other tubewells for irrigation and industrial uses, due to which the piezometric surface has been brought down. The sag in the piezometric surface in and around Kuttanad may be due to the free flowing wells in Kuttanad area and also due to the several pumping wells in Tannirmukkom- shertallai area. From the hydrograph of Vaikom aquifer at Kandiyoor site for the period November 1987 to May 1988, it is observed that the piezometric head rests at 2.3 m during the period from November to December but shows a decline to a level of 3.2 m during the period from January to May. Thus, it shows a fluctuation of the order of 0.9 to 1.0 m. Similarly the wells tapping Vaikom aquifer at Muttom, Karthikapalli, Karumadi and Karuvatta also show fluctuation of the piezometric head in the range of 0.23to 0.8 m agl. In general, it is observed that the deepest water level was recorded during April-May and the shallowest during July-August. The pressure head caused due to increase in water level in the recharge area is immediately transmitted to the coastal area. Apart from this, changes in the tides also affect the water level.

Fig 3.13 Isopach of Vaikom beds

The spatial variation in aquifer characteristics is high in Vaikom aquifers. The transmissivity values range from 6 m2 /day in the recharge area to 3855 m2 /day at Karuvatta and hyaraulic conouctivity ranges between 0.5 and 68.18 m/day.The storativity ranges from 2.5 x 10-4 to 4.1 x 10-3. The hydraulic parameters of the wells tested tapping this aquifer are given in Table 3.6

Table 3.6: Hydraulic parameters of Vaikom aquifers Well Location Dis- Dura- Draw Specific Trans- Storativity No. charge tion of down capacity missivity (s) (m3/hr) pumping (m) (lpm/m) (m2/day) (mts)

la Tirumulla- 28.36 1000 14.47 32.67 69.80 varam 18 Nallanickal 24.73 500 18.18 2 2.67 48.0

20 Karthikapalli 576.0 1020 2.23 430.49 2 300.0 - 22 Muttom 31.2 8 1500 4.40 118.50 180.0 - 23 Kandiyoor 49. 35 5 00 5.66 145.33 187.0 - 47 Panangad 21.60 500 2.65 174.50 193.6 - 55 Karumadi 79.14 1000 4.78 275.58 3476.94 - 56 Poruvazhi 2.62 500 7.57 5.78 12.833 - 57 Vayyankara 17. 37 1000 5.27 54.93 70.00 59- Karuvatta 96. 55 1440 6.76 238.04 3855.65 - 60 Ramankari 31.78 600 12.60 m 4.34 6.07 (main (Main well) well) 5.31 (Ob. 6.98 (Ob.well) 1.41x10-3 well) 61 Pulikeezh 603.28 5100 3.08 326.45 530.00 -

The specific capacity or the wells ranges from 5.79 to 436 lpm/m.It is found that maximum flow in the aquifer is from SE around Pallickal-Poruvazhi area towards NW and west. The flow directions in Alleppey and environs/are towards north and it branches to east due to the extraction in Kuttanad area. Piezometric levels in the Tertiary aquifer system The piezometric surface data of bore wells over a period has been used for the analysis of long term fluctuations of piezometric surface in the area. The piezometric surface in the Vaikom aquifers varied from 10 m amsl to 1m amsl during 1985 and at present it is in the range of 2 to 6m bmsl. Some of the piezometers in this aquifer were under free-flow conditions and now all of them are having piezometric heads below ground level. The piezometric head of Warkali aquifers were in the range of 2.8 m amsl to 10 m bmsl during 1985 and at present it is in the range of 4 to 20 m bmsl.

The piezometers taping the Tertiary aquifers at present are insufficient to create a meaningful contour map useful in quantifying the flow in the system. Most of the piezometers constructed earlier are defunct due to corrosion of pipes or destroyed. Fluctuations of piezometric surface are indicative of the changes in the groundwater regime. Seasonal fluctuations of piezometric surface reflect the changes between the pre- and post- monsoon seasons in a year, whereas long term fluctuations are indicative of the changes in groundwater storage over a period of time. The fluctuations in piezometric surface in the area, computed as the difference between the piezometric heads measured in observation bore wells during pre- and post-monsoon periods are shown in Table 4.4. The fluctuations of piezometric heads in the area varied from 1.18m at Haripad to -0.04m at Mankombu with an average fluctuation of 0.5m. The aquifer maps generated for Vaikom and Warkalli are given in Figs 3.14 and 3.15

Fig 3.14: Aquifer Map of Vaikom Formation

Fig 3.15: Aquifer Map of Warkalli Formation

4. 0 HYDROCHEMISTRY 4.1. Shallow ground water Hydrograph stations have been sampled during the pre-monsoon period of 1986 for water quality studies. The chemical analysis data of these samples is given in Appendix 6. The hydrograph stations in the Pamba study basin have been, sampled during January 1987 to study seasonal variations. The chemical analysis data of these samples is given in Appendix 7. The electrical conductivity of the shallow ground water zone during pre-monsoon period, as. represented by the samples of April '1.386, is in the range 30 to 2 700 micromhos/cam at 25°C with a mean value of 411. The chloride content is in the range 8 to 700 mg/1. The chloride content of higher than than 250 mg/1 have been recorded in the wells at Anjengo (Trivandrum district), Chellanam (Ernakulam district), Azhikode, Kakkathuruthi and Edathirinji (Trichur district) and. Kadalundi (Malappuram district). The distribution of electrical conductivity in the shallow wells is given in Fig 4.1. The fluoride content of 39 hydrograph stations in the coastal areas of Pamba and Kole lands is in the range less than 0.1 to 0.6 mg/1 during April 1986, with a mean of 0.1 mg/1. The seasonal variation in the quality of shallow ground water is studied by sampling and analysis of the hydrograph stations in Pamba basin. The pre-monsoon (April 1986) data for these wells is presented in Appendix 6, while the chemical analysis data of the samples of January 1987 is given in appendix 7. Of the 23 wells sampled during the two periods, the wells in Kuttanad region show increase in the electrical conductivity between April 1986 and January 1987. The increase is 2 to 40 times the value during April 1986. This is presumably due to the ingress of sea water in the rivers and channels. Wells in other parts generally show decrease in electrical conductivity ranging from 10 to 35 percent. 4.2. Hydrochemistry of the Tertiary aquifers The water from the Tertiary aquifers are characterised by high bicarbonate, fluoride and iron contents compared to the quality of water from the phreatic zones and also when compared to the deeper aquifers of the hard rock areas in the Project area. This is due to a combination of biogeochemical processes - weathering, ion exchange, dissolution and biological activity during the long residence time of the water in the Tertiary aquifers. The chemical analysis data of the water samples from the exploratory tubewells drilled by CGWB is given in Appendix-3. The trace metal data for the recent exploratory well is given in Appendix 4. Seventy deep wells drilled by the Kerala Water Authority for water supply were sampled during the Project studies and the chemical analysis data is given in Appendix 5. The ph, E.C. and HCO3 of samples are insitu values. The chemical characteristics of the water from the Tertiary beds viz. Warkalai formations, and the Vaikom aquifers are discussed below. 4.2.1 Warkalai aquifers - changes in water type The Warkalai formation yield fresh water with chloride content between 10 to 200 mg/1 in areas south of Alleppey. (A noted exception is the CGWB exploratory well at Mancombu, the water from which contains 720 mg/1 chloride). The fluorice content of the water from these aquifers is in the range 0.3 to 2.6 mg/1, the higher values of this range being observed in some of the wells around Alleppey. Sulphate is either absent or is only in traces. The iron content is in the range 0.1 to 14 mg/1with a mean of 2.2 mg/1. The in situ pH of the water from the wells in Kuttanad region is in the range 6.3 to 6.8 while that in the wells of the area further west (close to coast) is in the range 7.0 to

7.5. The nitrate contents also differ considerably between these two Zones. The nitrate content in Kuttanad region is in the range 5 to 17 mg/1 (mean = 11 mg/1) whereas that in the area further west is in the range less than 0.1 to 2.2 mg/l (means 0.6 mg/1).

Fig. 4.1 The spatial variation in electrical conductivity in the Warkalai aquifer The degree of mineralisation also is given as the electrical conductivity value. The figure shows that fresh water of Ca-Mg-HCO3 type occurs in areas south of Ambalapuzha-Thagazhi zone. The chemical composition of water, changes to Na-HCO3 type upto Alleppey area. Further north (Alleppey-Shertallai zone) hard brackish water of Ca-Mg-Cl type is noted and the water in the nortnernmost part of the Warkalais is saline.The changes in the degree and type of mineralisation of the water in the warkalai aquifer in the south to north direction can be explained as due to the movement of recharging fresh water through the sediments deposited under marine conditions.

The Ca-Mg-HCO3 type water results by the chemical action of rainwater containing CO2 on CaCO3 bearing minerals in the recharge zones. The calcium rich water moving northward releases sodium by ion exchange from clay minerals which had become sodium rich. This results in Na-HCO3 type water, which also explains the higher fluoride content. The alkaline waters are effective in releasing fluoride from the minerals like fluorapatite since hydroxide and F- have same charge and nearly equal ionic radii - - Ca5(PO4)3 F + OH →Ca5(PO4)3 (OH) + F Further north, where the flushing is incomplete, hard/brackish water of Ca-Mg-Cl or Na-Cl type can occur. Similar process has been observed in parts of Sweden (Agerstrand, 1981). The process is summarised as under: Marine environment →Brackish water of Na-Cl type

Fresh water of Ca-HCO3 type enters →Fresh water of Na-HCO3type

Futher flow of fresh Ca-HCO3 type → Fresh water of Ca-HCO3 type water. 4.2.2 Vaikom aquifers The Vaikom bed contains high yielding aquifers and are under artesian conditions. The water in these aquifers are fresh in the sauthern parts and brackish in the northern portions. The water is fresh south of Kuttanad and is used for public supply. The electrical conductivity in these portion is in the range 30 to 670 micromhos/cm at 2 5°C and the chloride varies from 4 to 75 mg/1. The CGWB exploratory well at Nallanickal (Well No. S 18) yields water with E.C. of 1840 micromhos/cm at 25°C and chloride content of 400 mg/1 and thus is an exception. The fluoride content of the water from Vaikom beds is in the range of 0.3 to 1.2 mg/1, while iron occursin concentration range of less than 0.05 mg/1 to 5.6 mg/1. The water in these aquifers in Kuttanad and further north are more mineralised with electrical conductivity in the range 1500 to 8800 micromhos/cm at 25°C. Fig 4.2 shows the distribution of electrical conductance in Vaikom aquifers.

Fig. 4.2 The spatial variation in electrical conductivity in the Vaikom aquifer

The water in the southern part is fresh and is of Ca-HCO3 type, whereas in the northern parts brackish water of Na-Cl type occurs. The water is under reducing conditions as evidenced by the low sulphate content, iron in the ferrous form and presence of H2S. The H2S content of the CGWB exploratory well at Pattanakad (well No.S.37) is 3.2 mg/1 and the water temperature is 38oC. These observations can be explained by sulphate reduction in these aquifers. Anaerobic micro-organisms activate the exothermic process of oxidation of organic matter by sulphate and thrive on the energy thus released.

C6H12O6 + 3SO4= 6 HCO3 + 3H2S.ΔH = - 220 K.cal. During the sedimentation process the organic matter in the sediments became rich in iodide due to biological fractionation. Subsequent movement of freshwater through the aquifer matrix can release the iodide into solution along with other soluble matter. Thus iodide can be used as a key parameter in tracing the origin of dissolved matter in ground water (Lloyds,1982). The iodide of the water samples collected from the Vaikom aquifers is in the range 6 to 300 micrograms per litre, which is far in excess of the concentration obtainable by fresh water-sea water mixing. Sea water of Kerala coast has 12 microgram of iodide per litre and 19,000 mg/1 chloride. The iooide to chloride ration inthe Vaikom formation waters is of the order of 4 x 10-4 , which is about 600 times that in sea water. The high iodide to chlorde ratio can be explained as due to the flushing of the salts deposited during the sedimentation process. The recharging Water gets enriched in iodide, chloride, sodium and other ions during the flushing process. Na/Cl ratio - a key parameter to identify, intrusion ana flushing of saline water The quality of water in the Tertiary aquifers indicates that the relative concentration of major ions and trace halides are different from that obtainable by sea water dilution. The deviation patterns have been used in the discussions above to show the flushing processes occurring in the aquifers. Another forceful parameter to inaicate the long term processes - flushing or intrusion - in coastal aquifer is the Na/Cl ratio (Jacks, G. 1987 and Mercads, A, 1985). In the course, of sea water intrusion, part of the sodium ions are exchangee for calcium and magnesium ions which are the predominent cations in the exchange sites of clay minerals in fresh water aquifers. The resulting water will be depletedin sodium. The chloride ions continue to remain in solution, since chloride does not undergo ion exchange, precipitation, complexing, oxidation-reduction or biological reactions (Hem,J.D. 1970). Thus the Na/Cl ratio during intrusion will be less than 0.85, the mole ratio in sea water. When flushing of saline water occurs, the direction of cation exchange is reversed and the opposite trends will be effective and Na/Cl ratio will be higher than that in sea water. The Na/Cl ratio of the water from Tertiary aquifers is plotted against the chloride content (Fig.20)• The theoretical trends for mixing, flushing and intrusion processes are shown in the inset diagram. It is seen that the the Na/Cl ratio for most of the water samples is higher than that in sea water-fresh water mixture and that these plot in the field of flushing in the diagram. The Warkalai aquifers are undergoing effective flushing, whereas the Vaikom aquifers in the northern part of the Project area are lagging behind and are in the brackish zone. 4.3 Characterization of hydrochemical processes The stable and radioactive isotopes were effectively used to evaluate the recharge mechanism in the area, surface and groundwater interaction, sea water ingress, and mixing of groundwater in aquifer systems. In the present study the environmental isotopes, deuterium, Oxygen-18, Tritium and Carbon-14 have been employed to understand the evolution of groundwater. The stable isotope (Deuterium and Oxygen-18) are useful in understanding the recharge mechanism and

interrelationship between aquifers, surface and groundwater in the area, whereas, the radioactive Isotopes (Tritium (3H) and Carbon-14 (14C) are used to know the age of groundwater. 4.3.1 Stable Isotopes Stable isotope content of groundwaters from the Recent alluvial aquifer varies between -3.8%o to l8 2 -2.7%o for δ O and between -18.2%o to -8.8%o for δ H, where as corresponding values for 2 l8 Tertiary aquifer is -3.4%o to -0.4%o and -13.7%o to +5.1%o respectively. The δ H - δ O relationships are shown in Fig 4.3 along with Global Meteoric Water Line (GMWL). The sampling locations and Isotope data are given in Table 4.1

Fig. 4.3 (δ2H - δl8O) relationships in groundwaters of the area

Most of the groundwater samples from alluvial and Tertiary aquifers fall on or close to the GMWL indicating that these waters are of meteoric origin and are not affected by secondary isotope effects such as evaporation or isotope exchange.

Table 4.1Isotope sampling locations and data of 18O, 2H, 3H and14C Sam Well EC Temp δD δ18 3H 14C Location Source Aquifer pH depth (μS/ OC (%o) O (TU) (pM ple 1 Kommady TW 145 Tertiary 598 29.4 8.4 -5.8 -1.8 0.2 1.6±0 2 Kalavur FTW 12 Alluvium 127 26.5 7.6 -16 -3 4.1

3 Kanjikuzhy FTW 12 Alluvium 92 27.5 7.3 - -2.9 3.5

4 Cherthala FTW 12 Alluvium 167 28 7.6 - -3.5 -

5 Kottaram TW 165 Tertiary 2975 32 8.4 -5.2 -2 0.9

6 Pattanakkad TW 126 Tertiary 1829 32.5 8.0 -5 -2.3 1

7 Velliyakulam TW 140 Tertiary 1531 31 7.9 -5 -1.8 0.2

8 Thanneermukkom FTW 12 Alluvium 100 27 7.8 -8.6 -2.5 -

9 Thanneermukkom TW 150 Tertiary 1090 31 7.8 -8.4 -2.2 0.7

10 Thanneermukkom SW Surface 7408 28.5 8.2 6.6 0.1 3.2

11 Muhamma DW 5 Alluvium 2368 29.6 7.1 - -2.4 -

12 Karumady TW 326 Tertiary 3628 30 8.8 -4.6 -1.5 1 0.2±0

13 Thookkulam TW 155 Tertiary 518 31.5 8.1 -0.8 -1.1 0.1 0.1±0

14 Nedumudi TW 61 Tertiary 714 31 6.8 - -2.5 1.6 2.4±0

15 Pallathuruthy SW Surface 495 28.5 7.6 1.1 -0.6 3.6

16 Pallathurthy TW 174 Tertiary 1448 30.9 7.5 -6.7 -2.2 0.9

17 Ambalapuzha TW 130 Tertiary 358 31 7.6 -2.1 -1.8 0.7

18 Purakkad TW 90 Tertiary 649 31 8.0 -2.2 -1.1 0.5

19 Thottappally TW 175 Tertiary 393 31 7.3 5.1 -0.8 0.8

20 Arathungal TW Tertiary 908 27 7.2 - -2.2 2.5

21 Cherthala TW Tertiary 4174 29 7.2 -4 -1.3 0.5

22 Kaipuram TW 160 Tertiary 122 28 6.8 - -3.1 3.9

23 Pazhaveedu TW Tertiary 729 28 8.3 -1.6 -1.2 0.8

24 Viyapuram TW Tertiary 553 29 7.1 -5.1 -1.4 0.6

25 Komalapuram TW 100 Tertiary 1260 26 7.0 -6.6 -1.6 0.7

26 Karuvatta DW 4 Tertiary 107 30 6.9 -3.8 -1.7 3.8

27 Karuvatta TW 81 Tertiary 353 29 7.0 -3.2 -2.3 0.6

28 Haripad TW Tertiary 426 29 6.7 - -1.2 0.6

29 Thakazhi TW 66 Tertiary 361 29 6.7 -0.6 -1.6 0.6

30 Neerkunnam TW 140 Tertiary 375 30 7.5 3.3 -0.4 0.5

31 Chandanakavu TW 145 Tertiary 1320 30 7.1 -3.4 -1.4 -

32 Mararikulam TW 92 Tertiary 2088 30 7.2 -8.6 -1.7 0.8

33 Preethikulangara TW Tertiary 1320 7.5 -4.2 -1.9 4.2 1.52±

34 Preethikulangara TW phreatic 4260 8.5 -2.9 -1.7 4.5 4.6±0

35 Alamthuruthy TW 31 Tertiary 1855 29 7.2 -2.9 -7.3 0.7 11.9±

36 Mararikkulam TW Tertiary 2370 30.7 6.9 -5.4 -2.6 2.8 10.9±

37 Ramankari TW 57 Tertiary 2230 30.2 6.8 - -2.5 2.3 45.9±

38 Muttom TW 68 Tertiary 635 28.9 7.4 - -2.8 21.3±

39 Kandiyur TW 20 Tertiary 194 28.8 6.8 -8.2 -2.9 3.2 55.9±

40 Kandiyur TW 145 Tertiary 283 28.8 6.7 -8.6 -3.4 3.3 80.6±

41 Kanjikuzhy PZ1 TW 45 Alluvium 475 29.2 7.5 - -3 2.6

42 Kanjikuzhy PZ4 TW 35 Alluvium 1358 31.6 7.2 - -3.8 3.7

43 Preethikulangara TW 218 Tertiary 5060 31.2 9.0 -4.8 -2.6 1.3

44 Podiyadi TW 56 Warkali 1234 28.1 7.4 -2.9 -6.4 0.3 98±1

44 Vallikkavu TW 30 Warkali 267 28.5 6.7 - -2.8 2.2

45 Thakazhi PZ2 TW 44 Alluvium 957 29.7 7.8 - -3.8 -

46 Thakazhi PZ3 TW 20 Alluvium 2820 29.7 7.7 - -3.6 -

W- Warkali, V-Vaikom, Q-Quilon , DW –dugwell TW-Tube well, FTW- Filter point Tube well, SW-surface water

The stable isotopic composition of groundwater from the unconfined aquifer is slightly depleted compared to the mean annual precipitation. The depletion in stable isotopes indicates that the recharge to this aquifer occurs mainly during intense storm events, which are quite common in the monsoon season. In large rain events, isotopic depletion is caused by the preferential rainout of heavier isotopes. In δ2H - δ 18O plot, most of the samples from the alluvial and Tertiary aquifers form distinct clusters showing that these two aquifers are not interconnected while samples from Vaikom and Warkali aquifers form a single group indicating that they are interconnected at few places through Quilon beds, which is a limestone aquifer. 4.3.2 Salinisation mechanism and evolution of groundwater. Water samples from the Tertiary aquifers are in general Na-Cl type in the central part of the study area. Reduction in hardness is seen along the flow path in the groundwaters of Warkali aquifer, i.e., natural freshening is taking place in this aquifer. Trends in Chadha’s diagram show that subsequent increment of Na+ in waters of Warkali along the flow path is caused by exchange of both Ca and Mg (cation exchange). Isotopes are recognized as an essential tool in understanding salinisation processes, especially when chemistry of waters undergo secondary changes such as ion exchange, precipitation etc. Generally, stable isotopic composition of groundwater will not change during dissolution and flushing of dry salts. However, salinity derived from mixing of saline solutions eg. seawater with fresh water, give rise to waters of different salinity and isotopic concentration and fall in a mixing line between these components in δD - δ18O plot. If salinity is because of evaporative concentration, the samples may fall in an evaporation line, which will be typical of an evaporation process. Few groundwater samples from the unconfined alluvial aquifer in the coastal regions are brackish. They have measurable tritium and fall in the seawater freshwater mixing line in the δ D - δ 18O plot. Hence the brackishness could be due to modern seawater intrusion. As mentioned earlier, the quality of groundwater in the Tertiary aquifers changes from fresh to brackish as it moves from south to central part of the study area. The progressive increase in brackishness could be due to leaching of salts from the clay, as shown in the Chloride versus δ18O plot (Fig.4.4). However, the variation (enrichment) in δ18O without appreciable increase in Chloride is not due to evaporation, but can be explained by the paleo-aridity.

Fig. 4.4 Plot of Chloride versus δI8O in the Tertiary aquifers 4.3.3 Radioactive Isotopes (3H and 14C) Tritium content of groundwater from the alluvial aquifer varies from 3-4 TU, which is similar to the present day precipitation values indicating modern recharge. Tertiary aquifers contain negligible tritium except at the southeastern parts of the study area and their 14C values are in the range of <1 to 98 pMC. Using Pearson's model (Pearson and White, 1967), corrections were applied for the initial activity of 14C and the groundwater ages estimated for these Tertiary aquifers were in the range of 9,000 to 30,000 years Before Present (B.P). It indicates that these are paleowaters recharged in a distant past. In general, it has been found that 18O and 2H concentrations in precipitation are temperature dependent, and hence rains occurring in cooler climatic conditions are more isotopically depleted than at warmer conditions (Dansgaard, 1964). This temperature dependence along with the dating techniques can be used for the reconstruction of paleoclimate. The samples representing tertiary aquifers are low in Tritium content and the plottings of δ18O versus 14C in Fig 4.5 shows decrease in 14C content (or increase in groundwater ages) with an increase in δ18O. This indicates that these groundwaters might be recharged during arid and humid phases in a span of 9,000 to 30,000 years B.P. Groundwater samples from Tertiary formations in the southeastern parts of the study area have measurable tritium. 14C content of these samples ranges from 45 to 98 pMC. They fall in a mixing zone in the δ2H – δ18O diagram. It means that the Tertiary aquifers are getting some modern recharge from this area. It is further confirmed with the local hydrogeology that some parts of the Vaikom aquifer are outcropped in this area. However, this contribution seems to be small, as observed from the hydrogeological studies and piezometric level changes over the years.

Fig. 4.5 Variation of δl8O with 14C in the Tertiary aquifers Based on the existing isotope data and their analysis it is inferred that the groundwaters in the alluvial aquifer are of meteoric origin and are replenished periodically by modern precipitation. The very low tritium values in the Tertiary aquifers indicate lack of vertical recharge from the phreatic aquifer system due to the presence of thick clay layers below surface waters and wetlands as established from the study of bore well litholog under chapter 2. However, small amount of modern recharge takes place to the Tertiary aquifers from the southeastern parts of the study area. Similar isotopic characteristics of Warkali and Vaikom aquifers of Tertiary aquifer system and the similarity of water level response reflected in hydrographs suggest their interconnection through the Quilon limestone aquifer in many places. Deep groundwaters in Kuttanad area are paleowaters which might have recharged during arid and humid phases in the past. Brackishness in the unconfined aquifer along the coastal regions and adjacent to brackish water bodies are due to mixing of modern seawater / brackish water with the fresh water in the aquifer system. The hydrochemistry in Tertiary aquifers are not modified by seawater intrusion and salinity in this aquifer system is mainly caused by leaching of salts and cation exchange processes. This could be established from hydrochemical studies and supported by the oxygen- 18 versus Cl and oxygen-18 versus carbon-14 plottings.

5.0 GROUND WATER RESOURCES 5.1 Shallow phreatic aquifer The phreatic aquifer, being easily accessible for common man, development of this aquifer is naturally high. To assess the resources available, a thorough study is necessary which will include the present level of development and scope for future development. There are several methods for the evaluation of the same viz. water balance method, rainfall-runoff method, water level fluctuation method etc. Since the sedimentary formations in this area are spread over the westernmost portions of the drainage basins, a correct assessment of the phreatic aquifer in each basin is not possible. Hence the water level fluctuation method was adapted so that the same in part of the basins can also be computed. The water level fluction between pre and post monsoon was taken and it was multiplied by the area to know the volume of aquifer saturated every year. This was multiplied by the specific yield to get the recharge. The specific yield values were taken from the pump test data. The average specific yield values for alluvial formation are 12% and for laterites it is 4.66%. The resource available in the phreatic zone is given in Table 5.1.

Table 5.1: Groundwater Resource available in the Study area particulars (MCM) Net Annual Ground Water Availability 1835 Existing Gross Ground Water Draft for Irrigation 238 Existing Gross Ground water Draft for domestic and industrial water supply 480 Existing Gross Ground Water Draft for All users 718 Provision for Domestic and industrial use upto 2025 502 Net Ground Water Availability for future irrigation development 615 (Source- Dynamic GW Resources of Kerala) Here the draft for domestic and industries is double than the draft for irrigation as the paddy agriculture is predominantly depends on the surface water. There is ample scope for GW development Around 615 MCM is available for future irrigation requirement.Except Mukhathala block in Kollam district and Chirayinkeezh block in Trivandrum district, all other blocks are in safe category. 5.1.1 Additional Recharge potential Kuttanad wetland is known for its water logged,low lying nature, characterized by shallow water table and the cultivation is carried out below MSL.In areas with shallow water level/ low lying areas,the estimation of annual recharge alone is erroneous as it leads to the underestimation of the resources.Therefore GEC has recommended that in water logged and shallow water level areas, ground water may be developed till the water level reaches 5 m bgl so that the ground water reservoir can be drawn to the optimum limit before the onset of monsoon.The resource is estimated based on premonsoon water level to 5 m depth are potential and would be available for development in addition to the annual recharge. Potential recharge has been separately calculated for this area and summerised in Table 5.2. Total potential recharge is about 414 MCM in the area.

Table 5.2: Additional Potential Recharge for shallow water areas

Additional Potential Recharge for shallow water areas Sl. No. Assessment Unit/ District Potential Recharge in water Potential Recharge in flood Total Annual Additional logged and shallow water table prone area Potential Ground Water area Recharge (1) (2) (1+2) District : Alappuzha 1 Ambalapuzha 1433.12 0.00 1433.12 2 Aryad 2807.04 0.00 2807.04 3 Champakulam 8298.48 0.00 8298.48 4 Chenganur 2709.50 0.00 2709.50 5 Haripad 2973.12 0.00 2973.12 6 Kanjikuzhi 1961.76 0.00 1961.76 7 Muthukulam 3412.80 0.00 3412.80 8 Pattanakad 4870.21 0.00 4870.21 9 Thaikattussery 5026.56 0.00 5026.56 10 Veliyanad 6310.10 0.00 6310.10 District Total 39802.69 0.00 39802.69 District : Kollam 1 Chavara 1600.00 0.00 1600.00 District Total 1600.00 0.00 1600.00 District : Kottayam 1 Vaikom 13.38 0.00 13.38 District Total 13.38 0.00 13.38 41416.07 0.00 41416.07 STATE TOTAL 414.16 MCM 414.16 MCM

The phreatic aquifer has been developed mostly through dug wells and to a limited extent by filter point wells. Realistic figures of the exact number of groundwater extraction structures are lacking and computation of draft has been made in a rational way with the data available.The coastal alluvium has got an average resource of 0.3 to 0.5 MCM/km2. This can be developed by shallow dug wells. Filter point wells are feasible wherever saturated sand thickness exceeds 5 m. The areas suitable for filter point wells are identified around Iravipuram, Chavara, Ochira,Kayamkulam, Alleppey, Shertallai, Vypin Island, Ponnani, Chamravattom, Purathoor and Tirur. 5.2. Deeper confined aquifers Out of the four formations in the Tertiary group, two viz. Warkalai and Vaikom are productive and development is mostly restricted to these. The third one Quilon is a poor aquifer and the Alleppey beds indicate brackish formation water. The data also is not sufficient for computation of the flow in the Quilon and Alleppey beds. The details ofthe Warkalai and Vaikom aquifers are given below. 5.2.1.Warkalai This being the topmost or shallowest potential aquifer in the Tertiary system is easily, accessible and hence, maximum development is in this aquifer. The total flow in this aquifer is 63.44 MCM. Maximum flow is in the Kallada basin which is 27-39 MCM followed by Pamba basin

25.19, and Meenachil basin 6.78 MCM. Rest of the fi.gw is inVamanapuram and Ithikkara basins. The draft is around 32 MCM of which 8 MCM is in Alleppey and 11 MCM in Kuttanad area, where the warkalai aquifers are maximum developed. About 66% of the resource is still available for development. It is found that in Alleppey area the tube wells have been drilled at a closer spacing of 15 to 30 metres which has resulted in lowering of the piezometric surface due to interference. Studies carried out in the area have indicated that the radius of cone of depression is between 500 and 750 m for two days of continuous pumping and hence the distance between two tubewells should be atleast 1.5 km. It is inferred that a basin boundary west of the coast is preventing the salt water intrusion towards inland. 5.2.2.Vaikom. This aquifer is mainly developed only around Quilon and the eastern peripheral area of the sedimentary basins, even though it is a highly potential aquifer. The flow in this aquifer is computed to be 43 MCM of which 10 MCM is brackish water with E.C range of 2500-3500 micromohs/cm at 25°C. The maximum flow is in Kallada basin being 20.3 MCM followed by. Pamba basin. The radius of influence for 10 days pumping is found to be 700 in and hence the minimum distance between twotubewells should be l.4 km. The present draft from this aquifer is estimated to be around 4.19 MCM leaving a bright scope for future development. The data is limited and hence the influence of a boundary of salt water-fresh water interface along the west is not known. However, as in the case of warkalai aquifer, care may be taken to keep the tubewells as much away as possible.

Appendix 6 : Block wise ground water resource in the study as on March ,2011

Appendix 6: Block wise ground water resource in the study area as on March 2011

SL.NO DISTRICTS BLOCKS Net Annual Exisiting Exisisting Existing Provision for Net Ground Stage of Category Ground Gross Gross Ground Gross Domestic Water Ground Water Ground water Draft for Ground and Availability for water Availability Water domestic and Water Draft industrial use future irrigation Development Draft for industrial water for All upto 2025 development Irrigation supply users Semi 1 Thiruvananthapuram Chirayinkeezhu 1744 333.27 972.85 1306.12 998.9 411.83 74.89 Critical 2 Thiruvananthapuram Varkala 1819.78 305.22 879.48 1184.7 903.12 611.44 65.1 Safe 3 Thiruvananthapuram Kilimanoor 3037.98 427.78 1055.67 1493.45 1084.05 1516.16 49.16 Safe 4 Alappuzha Bharanikkavu 4294.29 423.15 760.66 1183.81 766.22 3104.93 27.57 Safe 5 Alappuzha Haripad 3165.44 435.1 731.9 1167 657.21 2073.13 36.87 Safe 6 Alappuzha Aryad 2731.56 514.96 1362.5 1877.46 1372.46 844.14 68.73 Safe 7 Alappuzha Pattanakkad 3372.67 345.46 1021.87 1367.33 960.47 2066.74 40.54 Safe 8 Alappuzha Mavelikkara 4034.36 184.76 789.44 974.2 794.46 3055.15 24.15 Safe 9 Alappuzha Ambalappuzha 2097.24 569.27 624.79 1194.06 621.11 906.86 56.93 Safe 10 Alappuzha Kanjikkuzhy 2949.53 128.97 743.48 872.45 748.92 2071.64 29.58 Safe 11 Alappuzha Muthukulam 4358.69 227.65 1149.35 1377 1058.56 3072.48 31.59 Safe 12 Alappuzha Champakkulam 3988.35 69.82 495.66 565.48 499.26 3419.27 14.18 Safe 13 Alappuzha Thaikattussery 3581.65 95.65 683.66 779.31 687.75 2798.25 21.76 Safe 14 Alappuzha Chengannur 4881.3 806.46 866.77 1673.23 871.59 3203.25 34.28 Safe 15 Alappuzha Veliyanad 3705.96 92.17 624.79 503.89 414.73 3199.06 13.6 Safe 16 Ernakulam Palluruthy 1609.01 150.34 318.3 468.64 329.56 1129.11 29.13 Safe 17 Ernakulam Mulamthuruthy 2984.06 661.44 1079.24 1740.68 1140.05 1182.57 58.33 Safe 18 Kollam Chadayamangalam 3727.92 571.64 997.3 1568.94 1061.57 2139.71 42.09 Safe Semi 19 Kollam Mukhathala 3281.94 369.34 2077.47 2446.81 2724.95 187.65 74.55 Critical 20 Kollam Chavara 2082.05 266.62 964.05 1230.67 982.99 832.44 59.11 Safe 21 Kollam Vettikkavala 2837.43 491.58 940.83 1432.41 960.01 1385.85 50.48 Safe 22 Kollam Oachira 3314.45 446.86 1036.7 1483.56 1057.93 1809.66 44.76 Safe 23 Kollam Chittumala 2530.83 488.1 1056.23 1544.33 1077.96 964.77 61.02 Safe 24 Kollam Ithikkara 2729.34 339.5 1123.01 1462.51 1146.11 1243.73 53.58 Safe 25 Kollam Sasthamkotta 2334.3 451.32 986.44 1437.76 1006.49 876.49 61.56 Safe

26 Kollam Kottarakkara 2260.56 431.6 842.83 1274.43 858.76 970.2 56.38 Safe 27 Kottayam Madappally 5212.2 573.28 1192.57 1765.85 1211.41 3427.51 33.88 Safe 28 Kottayam Ettumanoor 3088.56 312.38 907.35 1219.73 921.69 1854.49 39.49 Safe 29 Kottayam Uzhavoor 3937.14 529.3 730.06 1259.36 1045.61 2362.23 31.99 Safe 30 Kottayam Kaduthuruthy 4679.05 628.42 711.82 1340.24 723.06 3327.57 28.64 Safe 31 Kottayam Pallom 5699.28 519.43 1377.07 1896.5 1398.82 3781.03 33.28 Safe 32 Kottayam Vaikom 3062.17 427.65 181.12 608.77 183.98 2450.54 19.88 Safe 33 Pathanamthitta Pandalam 2678.2 686.14 657.64 1343.78 632.86 1359.2 50.17 Safe

34 Pathanamthitta Pulikeezh 2208.1 292.1 688 980.1 662.08 1253.91 44.39 Safe 35 Pathanamthitta Konni 4950.76 384.18 780.06 1164.24 750.67 3815.91 23.52 Safe 36 Pathanamthitta Elanthoor 2284.41 373.88 454.88 828.76 437.74 1472.79 36.28 Safe 37 Pathanamthitta Parakode 6256.81 859.52 1089.3 1948.82 1048.26 4349.02 31.15 Safe

Fig 5.1 shows the categorization of blocks. Being semi critical blocks , Chirayinkeezh and Mukhathala blocks have highest percentage of GW development (approximately 75%). Valiyanad block in Alapuzha district is least developed.

Fig 5.1 Map showing categorization of blocks

5.3 Gound Water Resource of Warkalai and Vaikom Aquifer (Based on SIDA Project) During SIDA assisted coastal Kerala ground water project (1983-88), the resources of Warkalai and vaikom aquifer have been computed and summerised below. (a) WARKALI AQUIFER (i) Annual Ground Water Flow in the Warkali Aquifer :- 63.44 MCM (ii) Annual Ground Water Draft from the Warkali Aquifer :- 22 MCM (22 MCM through tube wells catering mainly to drinking Water Supply of Coastal Village and Towns out of which 18 MCM in Alleppey Town and Kuttanad Area.)

(b) VAIKOM AQUIFER (i) Annual Ground Water flow in the Vaikom Aquifer :- 43 MCM (ii) Brackish Water with Ec in the range of 2500 to 3500 micromhos :- 10 MCM (iii) Annual Draft in the Southern and eastern peripheral area :- 4.2 MCM (iv) Balance Water Available for future development in Tertiary Aquifer 106.44 -(22+10+4.2) = 70 MCM In order to obtain the more realistic figure CGWB, KR proposed to construct additional number of Pz in study area to evaluate the flow net.

6.0 GROUND WATER RELATED ISSUES The ground water issues phreatic aquifer system is mainly associated with microbial contamination from anthropogenic sources. Shallow water conditions in the coastal areas and the wetland areas of Kuttanad and Kole lands are susceptible for such pollution. Where as the deeper aquifers are mainly having geogenic contaminations such as iron and fluoride. The major issue with the Tertiary aquifers is degradation of aquifer systems as result of faulty construction of wells and consequent well failures. (a)Geogenic factors The shallow phreatic aquifer is always under the influence of flood waters and highly contaminated due to high permeability and human activities.From the analysis of ground water samples, the following blocks listed in table 5.1 were considered to be affected with high concentration of Iron,Flouride, Nitrate and heavy metals. High Iron concentration is widely spreaded through out the area and is summerised below in the table.In case of Chavara blockin Kollam district, the ground water pollution is due to the presence of Rare earth elements and its indiscriminate and unscientific mining practices. Fluoride hazard Ground water in phreatic aquifers have fluoride concentration within permissible limit, in the range of 0.08 to 0.62 mg/l. However, a few tube wells tapping deeper confined aquifers around Alappuzha urban area ( under Aryad block) have fluoride concentration in the range of 1.7 to 2.56 mg/l.

Table 6.1: Sstatus of quality problems encountered in the study area District Block Quality Problems Category encountered (in parts of the block) Alapuzha Iron, Fluoride (Deeper Safe Aryad zone) Kanjikkuzhy Iron Safe Mavelikkara Iron Safe Muthukulam Iron, Nitrate Safe Pattanakkad Iron Safe Thycattussery Iron Safe Kollam Chavara Iron, Heavy metals Safe Ithikkara Iron, Nitrate Safe Kottarakkara Iron Safe Mukhathala Iron Safe Oachira Iron, Nitrate Safe Sasthamkotta Iron Safe Vettikkavala Iron Safe Thiruvananthapuram Chirayinkil Iron, Nitrate Safe Varkala Iron, Nitrate Safe

Due to high dependence of recent alluvium especially all along the coast line to meet the domestic and irrigation activities , the public health is severe affected. This can be overcome by

tapping the Warkalai and Vaikom aquifers which have good potential in meeting the heavy draft required in the area. It is worthy to note that all along the coastal sediments, many tube wells have been drilledon Warkalai aquifer but failed prematurely to meet the requirement due to faulty design and unscientific pumping practices. Seawater Ingress The seawater ingress in the phreatic aquifer and the confined aquifers (Tertiary aquifers) haveto be evaluated separately as these aquifer systems represent different hydrogeological environments and evolution. Some of the dug wells tapping the phreatic aquifers and tube wells tapping the confined aquifers (tertiary aquifers) turned saline during summer due to multiple factors including over draft. The well connected coastal canals which permit invasion of the seawater by tidal action and the prawn culture farms along the coast add complexity the to the hydrodynamic equilibrium existing in the coastal tract, especially in the phreatic aquifer system. The exploitation of tertiary aquifer system started almost five decades back and there has been an increase in the draft over the years. Being a coastal aquifer system it deserves a very cautious, planned and judicious approach for its sustainable development. Otherwise, it may lead to over exploitation of the aquifers and consequent seawater intrusion, which will be disastrous effect. Tidal effect The tidal effect is felt mostly in the vicinity of the coast and areas adjacent to the streams and river inlets and areas surrounding backwaters, sometimes extending up to 12 km upstream. As a result, the quality of shallow groundwater very close to these rivers and its network is affected during summer months and the water becomes brackish. Water logging and conjunctive use Most of the Kuttanad area lie in submerged condition during major part of the year. It is subjected to the double hazards of flood discharge during monsoon and sea water ingress during summer on either side of Vembanad Lake. Excess water from the paddy fields are being pumped out to the discharge channel finally leads to ocean. Canal irrigation from the Pamba-Achenkoil project is practiced in areas outside of Alappuzha and the canals in Kuttanad are mainly used for navigation and for discharging the excess water pumped out of paddy fields and for discharging the flood from Pamba River to the Vembanad Lake. (b)Anthropogenic Factors. A major part of Kuttanad is vulnerable to bacteriological contamination due to the shallow water levels and existing sanitary practices. The area around Chandirur and Thuravur has a lot of fish processing factories. The fluid wastes from these factories are polluting the nearby canals and this in turn may pollute the sub-surface water. Proper scientific guidelines and monitoring of the industrial waste disposal system is necessary for preventing large scale groundwater pollution due to industrial waste. Bacteriological contamination of ground water from leach pits is a major problem affecting the safe drinking water supply to habitations in the coastal belt. Habitations in the close proximity of ocean, backwater canals and Vembanad Lake also suffers from quality deterioration due to ingress of saline water during the summer months. Extensive use of hazardous chemicals would cause environmental pollution and will also lead to destruction of natural enemies of pests.

7.0 GROUND WATER MANAGEMENT PLAN The coastal alluvium has got an average resource of 0.3 to 0.5 MCM/Km2. This can be developed by shallow dug wells. Filter point wells are feasible wherever saturated sand thickness exceeds 5 m. The areas suitable for filter point wells are identified around Iravipuram Chavara, Oachira, Kayamkulam, Alleppey, Shertallai, Vypin Island, Ponnani, Chamravattom, Purathoor and Tirur. The deeper Tertiary sediments can be developed through tubewells. There is scope of additional 200 tube wells in the area to the south of Thottapalli to depths of 100 to 150 m tapping the Warkalai aquifer with a minimum granular thickness of 15 m. This can meet the increasing demand for water in the coastal tracts to meet the domestic needs and it is suggedted that this can be exclusively reserved for public water supply. The deeper Vaikom aquifer in the Tertiaries has fresh water in the area south of Karuvatta and additional 175 tubewells in the depth range of 150-300m tappihg a minimum granular thickness of 20-25 m can be constructed. It is suggested that the development of this can be consicered to meet the water requirements of any industry that may come up in the future and also for public water supply. While developing the Warkalai and Vaikom aquifers through tubewells, it is suggested that the tubewells must be kept atleast 2 km away from the coast and the minimum distance between the pumping wells should be 1.5 km. The water in the Vaikom aquifer north of Karuvatta is brackish with E.C in the range of 2500 to 3500 micromhos/ cm at 25°C. Studies in the Kuttanad region have indicated that ground water in the Warkalai sediments is fresh. However, since there is already a development in the Warkalai aquifer in the Alleppey- Kuttanad region, further development in this area is to be restricted. Piezometers constructed in the coastal area have been utilized to determine the aquifer parameters and monitoring water levels and water quality. These have to be continuously monitored for water levels and quality. In addition, construction of sentry wells all along the coast between Quilon one Shertallai is recommended to monitor the water level and quality of individual Tertiary aquifers 7.1 Groundwater Development The studyarea is blessed with abundant groundwater resources in phreatic, semi-confined and confined conditions. Groundwater is mainly used for drinking and industrial purposes. The phreatic aquifer is tapped by dug wells and filter points generally fitted with 1.0 to 1.5 HP pumps. The deeper productive confined tertiary aquifers are extensively developed through submersible or vertical turbine pumps for drinking water supply.Presently aquifer wise quantity and quality could not be ascertained especially in the case of potential aquifers like warkalai and vaikom. The development potential of these tertiary aquifers can be quantified by further exploratory drilling and modeling work. The major management issue with the Tertiary aquifer system is protecting it from brackish water contamination due to faulty construction of wells. The construction tube wells tapping the Tertiary aquifers need to be regulated so as to construct the tube wells with more than 70% well efficiency. All tube well constructions by private agencies should be under the supervision and guidance of a hydrogeologist representing the state government.

7.2 Water Conservation and Artificial Recharge Coastal plain land is the predominant feature of studyarea where water level lies between 2m a msl to 2m b msl. The phreatic aquifer is composed of alluvial and beach sand. Since the sand is highly porous and permeable, natural recharge takes place automatically and a major part of the percolated rainwater goes off as rejected recharge which reaches to the drain channel as surface run off or sub surface runoff. Hence there is no immediate need for Artificial Recharge in the phreatic aquifer. However, in view of the large scale bacteriological contamination of ground water in the phreatic zone as well as the salinity problems in the coastal tracts, rainwater harvesting for direct use through storage tanks is feasible in the entire district. SUMMARY AND CONCLUSIONS The recent sediments comprising of coastal sands and alluvium of flood plains of Kuttanad and Kole lands and the Tertiary sediments constitute the phreatic aquifer.The recent sediments occur all along the coast with varying thickness. These attain a maximum thickness of 100 m north of Alleppey. Ground water is developed mostly through dugwells. The water table in this aquifer ranges from 1.0 to 6.0 m above mean sea level, while depth of the wells ranges from 2.75 to 10.6 m bgl. In certain patches, where sand thickness exceeds 5 m, filter point wells have been developed. The Tertiary formations comprise of four distinct units, named Warkalai, Quilon, Vaikom and Alleppey beds. Of these, the warkalai and Vaikom form potential confined aquifers.The Tertiary sediments attain their maximum thickness in the central parts between Kattoor and Nirkunnam, exceeding 600 m at the widest point of the coastal belt. The sediments have been deposited over a faulted crystalline basement. The warkalai aquifers are encountered in the boreholes only to the south of Cochin. The thickness of granular zones varies from 5 to 40 m. The piezometric head is 2.8 m above msl along the east (Kandiyoor) and is 10.0 m below sea level around Alleppey. The transmissivity values range from 130 to 711.61 m2/day. The resources in this aquifer are computed to be 63.44 MCM and the present draft is 22 MCM, of which tubewells in Alleppey town and Kuttanad region account for 19 MCM. Because of concentration of wells in this region and close spacings of wells in Alleppey town and continuous pumping, there is mutual interference and the water levels have gone down to 10 m below mean sea level in Alleppey town. The Vaikom beds constitute potential aquifers. The thickness of granular zone varies from 15 to 65 m. The piezometric surface ranges from l8 m above mean sea level around Poruvashi and is 5 m below mewn sea level around Quilon. The transmissivity values range from 22 to 3856 m2 /day. The resources in this aquifer are 43 MCM of which 10 MCM is brackish water. The present draft from this aquifer is 4.19 MCM and thus there is scope for development of this aquifer. The quality of waters in the phreatic aquifer is generally good. The waters are brackish in certain patches in the vicinity of Anjengo, Chellanum, Azhikode, Kakkathuruthy, Edathirinji, Kadalundi and in the coastal tracts of Ambalapuzha. The Warkalai aquifers are fresh upto Arthungal and brackish along the north. The water in the area south of Alleppey have Na-HCO3 type of composition and along north of Alleppey Ca-Mg- Cl type is noticed. The changes in this can be due to the movement of recharging fresh water through the sediments deposited under marine conditions. The calcium rich water moving northwards releases sodium by ion exchange from clay minerals and becomes sodium rich

resulting in Na-HC03 type of water. Further north the flushing is incomplete and hard/brackish waters of Ca-Mg-Cl occur. The formation waters in the Vaikom beds are fresh upto Karuvatta and are brackish northwards except certain pockets around Shertallai, Thannirmukkom area. The water in the southern parts are Ca-HC03 type, whereas in the northern part it is Na-Cl type. The Na/Cl ratio can be used as a forceful parameter to indicate a long term process - flushing or intrusion.

ANNEXURE-I STATIC DATA OF NHS AND KEY DUG WELLS IN STUDY AREA MONITORED BY CGWB

SL.NO LOCATION PANCHAYAT BLOCK MUNICIPAL CORPORATION DISTRICT TYPE AAP LONGITUDE LATITUDE 1 Charummood Chunakkara Bharanikkavu ALAPUZHA NHS 2013-14 76.600000 9.170000 2 Chettikulangara Pathiyoor Muthukulam ALAPUZHA NHS 2013-14 76.500000 9.210000 3 Idakunnam Noornad Bharanikkavu ALAPUZHA NHS 2013-14 76.618817 9.183433 4 Kandiyoor Mavelikkara ALAPUZHA NHS 2013-14 76.529300 9.250700 5 Kattanam Bharanikkavu Bharanikkavu ALAPUZHA NHS 2013-14 76.550000 9.170000 6 Kayamkulam Devikulangara Muthukulam ALAPUZHA NHS 2013-14 76.480000 9.160000 7 Kudasanad Palamel Bharanikkavu ALAPUZHA NHS 2013-14 76.670683 9.192350 8 Kuzhamathu Noornad Bharanikkavu ALAPUZHA NHS 2013-14 76.631567 9.206617 9 Mavelikara Mavelikkara ALAPUZHA NHS 2013-14 76.545050 9.252983 10 Muthukulam Muthukulam Muthukulam ALAPUZHA NHS 2013-14 76.450000 9.200000 11 Noornad Mavelikkara-Thamarakkulam Bharanikkavu ALAPUZHA NHS 2013-14 76.630000 9.170000 12 Ochira Krishnapuram Muthukulam ALAPUZHA NHS 2013-14 76.515000 9.146550 13 Pallarimangalam Mavelikkara-Thekkekkara Mavelikkara ALAPUZHA NHS 2013-14 76.535833 9.209633 14 Pandalam Noornad Bharanikkavu ALAPUZHA NHS 2013-14 76.630000 9.220000 15 Pattiyoor Pathiyoor Muthukulam ALAPUZHA NHS 2013-14 76.495000 9.208117 16 Thamarakulam Mavelikkara-Thamarakkulam Bharanikkavu ALAPUZHA NHS 2013-14 76.615033 9.145150 17 Vallikunnam Vallikunnam Bharanikkavu ALAPUZHA NHS 2013-14 76.553850 9.135017 18 Venmani Thazhakara Mavelikkara ALAPUZHA NHS 2013-14 76.600000 9.230000 19 Alapuzha Alapuzha ALAPUZHA NHS 2012-13 76.32 9.49 20 Arukutti Poochakkal ALAPUZHA NHS 2012-13 76.32 9.86 21 Chandirur Arur ALAPUZHA NHS 2012-13 76.31 9.85 22 Cherthala Cherthala ALAPUZHA NHS 2012-13 76.34 9.69 23 Edathua Edathua ALAPUZHA NHS 2012-13 76.48 9.37 24 Harippad Haripad ALAPUZHA NHS 2012-13 76.46 9.29 25 Kaithavana Alapuzha ALAPUZHA NHS 2012-13 76.34 9.47 26 Karuvatta Karuvatta ALAPUZHA NHS 2012-13 76.42 9.33 27 Mannar Mannar ALAPUZHA NHS 2012-13 76.55 9.31 28 Nedumudi Nedumudi ALAPUZHA NHS 2012-13 76.40 9.45 29 Neerkunnam Vandanam ALAPUZHA NHS 2012-13 76.35 9.41 30 Pacha Thakazhi ALAPUZHA NHS 2012-13 76.45 9.36 31 Parumala Parumala ALAPUZHA NHS 2012-13 76.55 9.33 32 Pattanakkad Pattanakkad ALAPUZHA NHS 2012-13 76.32 9.74 33 Purakkad Purakkad ALAPUZHA NHS 2012-13 76.37 9.35 34 Ramankari Veliyanad ALAPUZHA NHS 2012-13 76.45 9.43 35 Thaikkattusery Thykkattussery ALAPUZHA NHS 2012-13 76.36 9.79 36 Thakazhi Thakazhi ALAPUZHA NHS 2012-13 76.41 9.37 37 Thannirmukkam Thannirkukkam ALAPUZHA NHS 2012-13 76.39 9.68 38 Thurvurr Thuravoor ALAPUZHA NHS 2012-13 76.32 9.77 39 Valavanad Kalavoor ALAPUZHA NHS 2012-13 76.33 9.59 40 Theveri Parumala ALAPUZHA NHS 2012-13 76.52 9.31 41 Ambalapuzha Ambalapuzha ALAPUZHA NHS 2012-39 76.37 9.38 42 Champakulam Nedumudi ALAPUZHA NHS 2012-45 76.41 9.41 43 Eramallur Aroor ALAPUZHA NHS 2012-14 76.313 9.818 44 Kainady Pallathuruthy ALAPUZHA NHS 2012-43 76.46 9.49 45 Kainakari Kavalam ALAPUZHA NHS 2012-46 76.38 9.48 46 Kalavoor Kalavoor ALAPUZHA NHS 2012-22 76.327 9.568

47 Kanichukulangara Kanichukulangara ALAPUZHA NHS 2012-20 76.314 9.633 48 Kattur Alapuzha ALAPUZHA NHS 2012-21 76.31 9.579 49 Kavalam Kavalam ALAPUZHA NHS 2012-44 76.48 9.47 50 Kavalamkodam Muhamma ALAPUZHA NHS 2012-18 76.326 9.704 51 Kidangara Mampuzhakari ALAPUZHA NHS 2012-41 76.49 9.43 52 Kunnamkari Veliyanad ALAPUZHA NHS 2012-47 76.3 9.43 53 Mahadevikad Trikunnapuzha ALAPUZHA NHS 2012-37 76.43 9.26 54 Muttar Muttar ALAPUZHA NHS 2012-40 76.51 9.39 55 Nangiarkulangara Muttam ALAPUZHA NHS 2012-35 76.46 9.26 56 Ottappunna Cherthala ALAPUZHA NHS 2012-23 76.363 9.738 57 Panavally Thykkattussery ALAPUZHA NHS 2012-17 76.352 9.814 58 Pulinkunnu Pulinkunnu ALAPUZHA NHS 2012-42 76.45 9.45 59 Punnapra Punnapra south ALAPUZHA NHS 2012-48 76.34 9.44 60 Thottapalli Purakkad ALAPUZHA NHS 2012-38 76.39 9.32 61 Valavanad Kalavoor ALAPUZHA NHS 2012-19 76.328 9.59 62 Vanaswargam Kalavoor ALAPUZHA NHS 2012-24 76.341 9.608 63 Varekkad Thykkattussery ALAPUZHA NHS 2012-16 76.359 9.793 64 Veeyapuram Veeyapuram ALAPUZHA NHS 2012-36 76.46 9.33 65 Allummoodu Mayyanad Mukhathala KOLLAM NHS 2013-14 76.649750 8.851083 66 Anchallammud (DW) Thrikkadavoor Anchalummood KOLLAM NHS 2013-14 76.601528 8.928889 67 Ayathil Kollam KOLLAM NHS 2013-14 76.635333 8.894222 68 Chenkulam Pooyappally Kottarakkara KOLLAM NHS 2013-14 76.748861 8.877833 69 Ezhukone Ezhukone Kottarakkara KOLLAM NHS 2013-14 76.714250 8.980417 70 Iravipuram Kollam KOLLAM NHS 2013-14 76.620333 8.860861 71 Ittikkara Adichanalloor Ithikkara KOLLAM NHS 2013-14 76.690194 8.864333 72 Kappil Poothakkulam Ithikkara KOLLAM NHS 2013-14 76.684083 8.776139 73 Karunagapalli Karunagapally Karunagappally KOLLAM NHS 2013-14 76.530000 9.050000 74 Kottarakkara Kottarakkara Kottarakkara KOLLAM NHS 2013-14 76.773667 8.999000 75 Kottiyam Mayyanad Mukhathala KOLLAM NHS 2013-14 76.668861 8.866639 76 Kulakada Kulakkada Vettikkavala KOLLAM NHS 2013-14 76.750000 9.060000 77 Kumbalam Perayam Chittumala KOLLAM NHS 2013-14 76.660778 8.989944 78 Kundara (Hospital) Kundara Chittumala KOLLAM NHS 2013-14 76.671750 8.970389 79 Kureeppally Kottamkara Mukhathala KOLLAM NHS 2013-14 76.676139 8.919472 80 Kutavettur Veliyam Kottarakkara KOLLAM NHS 2013-14 76.746861 8.941194 81 Mannadi Kulakkada Vettikkavala KOLLAM NHS 2013-14 76.720000 9.080000 82 Nallila (DW) Nedumpana Ithikkara KOLLAM NHS 2013-14 76.701917 8.928306 83 Nedungolam Paravoor KOLLAM NHS 2013-14 76.682111 8.833750 84 Oyur Velinalloor Chadayamangalam KOLLAM NHS 2013-14 76.775861 8.874389 85 Paripally Kalluvathukkal Ithikkara KOLLAM NHS 2013-14 76.756278 8.812361 86 Pavithreswaram NHS Kunnathur Sasthamkotta KOLLAM NHS 2013-14 76.680000 9.050000 87 Pazhikara Paravoor KOLLAM NHS 2013-14 76.649917 8.811556 88 Perinad (Dw) Perinad Chittumala KOLLAM NHS 2013-14 76.637472 8.948444 89 Puthoor Pavithreswaram Vettikkavala KOLLAM NHS 2013-14 76.700000 9.030000 90 Quilon Kollam KOLLAM NHS 2013-14 76.583889 8.889778 91 Sasthamkotta Sasthamkotta Sasthamkotta KOLLAM NHS 2013-14 76.620000 9.043983

92 Tattamala Kollam KOLLAM NHS 2013-14 76.635278 8.872472 93 Thevalakkara Mynagapally Karunagappally KOLLAM NHS 2013-14 76.593383 9.022233 94 Ummannur Ummannoor Vettikkavala KOLLAM NHS 2013-14 76.820722 8.932861 95 Vallikavu Klapana Oachira KOLLAM NHS 2013-14 76.494817 9.092567 96 Aalumpeedika Alappad Karunagappally KOLLAM KW 2013-14 76.480000 9.110000 97 Adichanallur Adichanalloor Ithikkara KOLLAM KW 2013-14 76.712028 8.879889 98 Ambalamkunnu Velinalloor Chadayamangalam KOLLAM KW 2013-14 76.792917 8.900972 99 Ashtamudiseri Thrikkaruva Anchalummood KOLLAM KW 2013-14 76.598667 8.958750 100 Chakkuvalli(Sooranad) Sooranad South Sasthamkotta KOLLAM KW 2013-14 76.630000 9.080000 101 Chavara-panmana Panmana Chavara KOLLAM KW 2013-14 76.530000 9.000000 102 East Kallada East Kallada Chittumala KOLLAM KW 2013-14 76.650000 9.010000 103 Kalluvadakkal Kalluvathukkal Ithikkara KOLLAM KW 2013-14 76.745111 8.833167 104 Karippira Kareepra Kottarakkara KOLLAM KW 2013-14 76.720222 8.952333 105 Karuvel Ezhukone Kottarakkara KOLLAM KW 2013-14 76.704944 8.992639 106 Killikkallur Kollam KOLLAM KW 2013-14 76.632806 8.918306 107 Killoor Neduvathoor Kottarakkara KOLLAM KW 2013-14 76.744083 8.992806 108 Kottathala Kulakkada Vettikkavala KOLLAM KW 2013-14 76.730000 9.050000 109 Koyivila Thevalakkara Chavara KOLLAM KW 2013-14 76.577167 8.988528 110 Kundara Kundara Chittumala KOLLAM KW 2013-14 76.670972 8.955167 111 Kuttivattam Karunagapally Karunagappally KOLLAM KW 2013-14 76.530000 9.020000 112 Minambalam Kalluvathukkal Ithikkara KOLLAM KW 2013-14 76.737694 8.810917 113 Miyannur Pooyappally Kottarakkara KOLLAM KW 2013-14 76.741528 8.898278 114 Mukhathala - Kaniyamthodu Thrikkovilvattom Mukhathala KOLLAM KW 2013-14 76.654194 8.899250 115 Mukkunnapuram Chavara Chavara KOLLAM KW 2013-14 76.562500 8.987333 116 Mumpuzha Kottamkara Mukhathala KOLLAM KW 2013-14 76.653667 8.922833 117 Nedungulam Paravoor KOLLAM KW 2013-14 76.685111 8.836333 118 Neduvankavu Kareepra Kottarakkara KOLLAM KW 2013-14 76.734806 8.924417 119 Nellikunnam Ummannoor Vettikkavala KOLLAM KW 2013-14 76.775694 8.963389 120 Nindakara Neendakara Chavara KOLLAM KW 2013-14 76.540611 8.941111 121 Panaveli Vettikkavala Vettikkavala KOLLAM KW 2013-14 76.824667 8.972667 122 Paravur Tekkubhagam Poothakkulam Ithikkara KOLLAM KW 2013-14 76.669111 8.787500 123 Pavithreswaram Jn Pavithreswaram Vettikkavala KOLLAM KW 2013-14 76.698133 9.010000 124 Perumpuzha Elampalloor Mukhathala KOLLAM KW 2013-14 76.678500 8.938611 125 Pudakulam Poothakkulam Ithikkara KOLLAM KW 2013-14 76.698222 8.805000 126 Roaduvila Velinalloor Chadayamangalam KOLLAM KW 2013-14 76.810778 8.877750 127 Sankaramangalam Panmana Chavara KOLLAM KW 2013-14 76.535111 8.998528 128 Tanni Mayyanad Mukhathala KOLLAM KW 2013-14 76.636639 8.839417 129 Tekkumbhagam Thekkumbhagam Chavara KOLLAM KW 2013-14 76.560694 8.953806 130 Thirumullavaram Kollam KOLLAM KW 2013-14 76.552194 8.897333 131 Vallikkeezhu Kollam KOLLAM KW 2013-14 76.560194 8.910500 132 Vavvakkavu Oachira Oachira KOLLAM KW 2013-14 76.520000 9.100000 133 Velamanur Kalluvathukkal Ithikkara KOLLAM KW 2013-14 76.781056 8.830722 134 Veliyam Veliyam Kottarakkara KOLLAM KW 2013-14 76.768444 8.921528 135 Edavali Edava Varkala KOLLAM NHS 2013-14 76.701583 8.761750 136 Kallambalam Navaikulam Kilimanoor KOLLAM NHS 2013-14 76.789944 8.761972

137 Navaikulam Navaikulam Kilimanoor KOLLAM NHS 2013-14 76.800361 8.795583 138 Palayamkunnu Elakamon Varkala KOLLAM NHS 2013-14 76.739028 8.774222 139 Perumgulam Manamboor Varkala TRIVANDRUM NHS 2013-14 76.785222 8.705972 140 Varkala Varkala TRIVANDRUM NHS 2013-14 76.714194 8.731306 141 Manambur Manamboor Varkala TRIVANDRUM KW 2013-14 76.790889 8.732472 142 Muttanam Chemmaruthy Varkala TRIVANDRUM KW 2013-14 76.763028 8.767417 143 Nedumkanda Vettoor Varkala TRIVANDRUM KW 2013-14 76.738639 8.700861 144 Pallikkal Pallickal Kilimanoor TRIVANDRUM KW 2013-14 76.806111 8.829667 145 Thalavilamukku Navaikulam Kilimanoor TRIVANDRUM KW 2013-14 76.822556 8.778333 146 Tottakkadu Karavaram Kilimanoor TRIVANDRUM KW 2013-14 76.811306 8.753194 147 Vadaserikanam (Allanmoodu) Chemmaruthy Varkala TRIVANDRUM KW 2013-14 76.756278 8.742694 148 Adoor Kadampanadu Parakode PATHANAMTHITTA NHS 2013-14 76.710000 9.150000 149 Arnootimanalam Pandalam Thekkekara Pandalam PATHANAMTHITTA NHS 2013-14 76.580000 9.220000 150 Churakkod Kadampanadu Parakode PATHANAMTHITTA NHS 2013-14 76.720000 9.100000 151 Kadambanad Kadampanadu Parakode PATHANAMTHITTA NHS 2013-14 76.680000 9.080000 152 Kulanada Pandalam Pandalam PATHANAMTHITTA NHS 2013-14 76.660000 9.230000 153 Omallur Vallicode Konni PATHANAMTHITTA NHS 2013-14 76.750000 9.230000 154 Paranthal Thumpamon Pandalam PATHANAMTHITTA NHS 2013-14 76.700000 9.180000 155 Thatta Pandalam Thekkekara Pandalam PATHANAMTHITTA NHS 2013-14 76.730000 9.180000 156 Thumpamon Thumpamon Pandalam PATHANAMTHITTA NHS 2013-14 76.700000 9.220000 157 Mutoor Muthoor PATHANAMTHITTA NHS 2012-13 76.57 9.40 158 Peringara Kavumbhagam PATHANAMTHITTA NHS 2012-13 76.54 9.38 159 Pulikeezh Pulikeezh PATHANAMTHITTA NHS 2012-13 76.55 9.35 160 Anadasramam Changanacherry KOTTAYAM NHS 2012-13 76.55 9.46 161 Arunoottimangalam Arunoottimangalam Kaduthuruthy KOTTAYAM NHS 2012-13 76.50 9.80 162 Ayamkudi Kallara Kaduthuruthy KOTTAYAM NHS 2012-13 76.47 9.75 163 Changanassery Changanacherry KOTTAYAM NHS 2012-13 76.53 9.45 164 Edinillam Muthoor Pulikeezh KOTTAYAM NHS 2012-13 76.55 9.42 165 Ikarakunnam Ettumanoor Ettumanoor KOTTAYAM NHS 2012-13 76.54 9.66 166 Kaduthuruthi Kaduthuruthy KOTTAYAM NHS 2012-13 76.49 9.76 167 Kottayam Kottayam KOTTAYAM NHS 2012-13 76.52 9.59 168 Kumarakom Kumarakom Pallam KOTTAYAM NHS 2012-13 76.43 9.62 169 Palamkadavu Chembu Vaikom KOTTAYAM NHS 2012-13 76.44 9.79 170 Pallam Chingavanam Pallam KOTTAYAM NHS 2012-13 76.51 9.53 171 Pulikuttiserry Kudamaloor Ettumanoor KOTTAYAM NHS 2012-13 76.49 9.63 172 Thalayolaparambu Thalayolaparambu Vaikom KOTTAYAM NHS 2012-13 76.49 9.79 173 Tiruvarppu Thiruvarpu Pallam KOTTAYAM NHS 2012-13 76.47 9.58 174 Vaikam Vaikom Vaikom KOTTAYAM NHS 2012-13 76.39 9.75 175 Vechur Vechoor Vaikom KOTTAYAM NHS 2012-13 76.42 9.66 176 Velloor Velloor Kaduthuruthy KOTTAYAM NHS 2012-13 76.45 9.83 177 Udayanapuram Vaikom KOTTAYAM NHS 2012-13 76.395 9.773 178 Bramamangalam Brahmamangalam KOTTAYAM NHS 2012-13 76.423 9.815 179 Chempu Chempu KOTTAYAM NHS 2012-13 76.396 9.81 180 Chengalam Chengalam KOTTAYAM NHS 2012-13 76.465 9.593 181 Ettumanur Ettumanoor KOTTAYAM NHS 2012-13 76.568 9.673

182 Kalathur Kalathur KOTTAYAM NHS 2012-13 76.544 9.721 183 Kudavechur Vechoor KOTTAYAM NHS 2012-13 76.421 9.678 184 Mannanam Mannanam KOTTAYAM NHS 2012-13 76.52 9.648 185 Mevallur Velloor KOTTAYAM NHS 2012-13 76.464 9.844 186 Nindur Neendur KOTTAYAM NHS 2012-13 76.505 9.687

ANNEXURE-II DETAILS OF WATER LEVES FROM THE NHS AND KEY DUG WELLS IN THE STUDY MONITORED BY CGWB

TOTAL NOVEMBER APRIL NOVEMBER SL.NO LOCATION MP DIA DEPTH MAY 12 AUGUST 12 12 13 AUGUST 13 13 1 Charummood 0.90 4.10 30.00 9.50 10.10 12.65 2 Chettikulangara 0.80 2.00 4.50 2.75 1.20 1.05 3 Idakunnam 0.90 2.20 14.20 11.70 11.30 11.00 4 Kandiyoor 0.65 1.20 4.90 3.30 2.48 1.80 5 Kattanam 0.80 3.10 15.90 13.30 10.90 11.58 6 Kayamkulam 0.50 1.10 4.50 1.30 0.33 0.35 7 Kudasanad 0.70 2.10 8.90 6.30 4.50 5.25 8 Kuzhamathu 0.90 2.10 16.00 12.80 10.90 11.40 9 Mavelikara 0.60 1.40 4.50 3.55 1.30 1.84 10 Muthukulam 0.80 1.70 5.00 2.20 1.10 1.90 11 Noornad 0.80 2.10 12.50 7.60 9.30 9.70 12 Ochira 0.60 0.90 7.00 5.50 1.90 3.21 13 Pallarimangalam 0.80 1.50 3.60 2.30 1.20 1.05 14 Pandalam 0.80 2.00 8.90 5.60 4.00 3.40 15 Pattiyoor 0.80 1.00 3.30 1.40 0.80 0.60 16 Thamarakulam 0.90 2.00 6.70 3.40 3.30 3.27 17 Vallikunnam 1.00 1.70 5.20 3.10 1.15 1.36 18 Venmani 0.90 2.00 4.50 3.00 2.30 0.68 19 Alapuzha 0.89 1.28 3.97 2.16 1.91 1.87 20 Arukutti 0.58 1.9 3.35 2.87 0.95 1.5 21 Chandirur 0.86 1.05 3.8 2.64 0.8 1.36 22 Cherthala 0.8 1.5 2.1 1.72 0.66 0.42 23 Edathua 0.46 1.75 3.5 1.76 0.49 NA 4

24 Harippad 0.78 1.21 4.55 2.77 0.82 0.67 25 Kaithavana 0.7 1.1 2.2 1.7 0.9 1.5 26 Karuvatta 0.7 2.4 4.1 0.77 0.8 0.57 27 Mannar 0.7 1.3 5.95 28 Nedumudi 0.75 1.95 4.25 0.3 0.27 0.3 29 Neerkunnam 0.71 1.05 3.77 1.65 1.29 0.8 30 Pacha 0.5 1.6 3.7 1.77 0 0.3 31 Parumala 0.8 2 9 6.6 5.65 5.6 32 Pattanakkad 0.75 1.5 3.4 1.95 0.2 0.47 33 Purakkad 0.6 1.1 4.2 2.66 2.5 2.06 34 Ramankari 0.32 1.3 3.3 0.6 0 0.3 35 Thaikkattusery 1 1.6 3.8 2.2 0.41 1.56 36 Thakazhi 0.7 1.9 3.65 2.12 1.05 0.3 37 Thannirmukkam 0.6 2.4 2.7 0.6 1.03 38 Thurvurr 0.6 1.2 4.45 3.3 1.32 1.4 39 Valavanad 1 1.8 3.7 1.65 0.24 0.29 40 Theveri 0.9 1.55 6.03 2.15 0.6 0.6 41 Ambalapuzha 0.7 1.2 3.3 0.7 0.42 42 Champakulam 0.7 0.8 3.7 0.7 1.3 43 Eramallur 0.75 1.4 3.5 1.57 44 Kainady 0.75 1 3.5 0.35 1.45 45 Kainakari 0.5 1.1 3.3 0.6 1.11 46 Kalavoor 0.5 1.1 3.3 0.6 1.03 47 Kanichukulangara 1.1 1.8 3.4 1.72 1.83 48 Kattur 0.55 1.1 3.32 0.41 1.04 49 Kavalam 0.8 2.1 3 0.8 1.4 50 Kavalamkodam 0.75 1.8 2.6 1.05 1.58 51 Kidangara 0.7 1.1 2.1 0.9 1.01 52 Kunnamkari 0.5 1.05 3.05 0.85 53 Mahadevikad 0.6 1.1 2.3 0.5 0.7

54 Muttar 0.7 2.1 2.6 1 1.35 55 Nangiarkulangara 0.75 1.1 3.9 0.8 1.05 56 Ottappunna 0.85 2 3.5 1.59 2.47 57 Panavally 0.9 1.75 2.9 1.02 58 Pulinkunnu 0.8 1.7 2.8 0.35 0.58 59 Punnapra 0.6 1.15 3.25 3 1.5 60 Thottapalli 0.6 1 1.4 0.4 2.5 61 Valavanad 1 1.8 3.7 0.24 0.53 62 Vanaswargam 1.2 2 2.8 0.72 1 63 Varekkad 1 1.6 3.8 1.38 64 Veeyapuram 0.8 1.1 2.7 0 1 0.5 65 Allummoodu 0.73 1.65 9.57 8.84 4.36 5.92 66 Anchallammud (DW) 0.65 1.60 10.13 9.49 6.93 7.64 67 Ayathil 0.80 1.40 8.90 8.00 4.41 5.60 68 Chenkulam 0.75 2.35 6.55 6.40 3.81 4.67 69 Ezhukone 0.76 1.72 5.21 5.12 1.57 2.87 70 Iravipuram 0.77 0.82 3.95 3.67 1.24 1.77 71 Ittikkara 0.90 2.00 17.30 17.25 15.10 15.28 72 Kappil 0.80 0.70 11.80 10.94 9.37 10.96 73 Karunagapalli 0.85 1.50 5.00 3.35 2.15 2.29 74 Kottarakkara 0.80 2.02 18.27 17.30 10.69 12.85 75 Kottiyam 0.95 2.10 22.15 21.70 6.95 7.52 76 Kulakada 0.60 2.00 11.50 8.40 7.70 5.35 77 Kumbalam 0.78 1.72 26.22 26.22 19.07 19.71 78 Kundara (Hospital) 0.73 1.63 10.92 10.10 4.82 5.08 79 Kureeppally 0.84 1.75 11.16 10.44 8.72 9.26 80 Kutavettur 1.20 2.10 8.19 8.10 6.23 6.40 81 Mannadi 0.70 2.00 8.00 4.20 1.55 1.50 82 Nallila (DW) 0.90 1.70 8.90 5.24 5.50 5.75 83 Nedungolam 0.80 1.60 10.90 10.55 7.94 8.93

84 Oyur 0.90 1.90 12.95 11.28 5.65 7.33 85 Paripally 0.70 0.00 13.30 13.25 7.16 9.32 86 Pavithreswaram NHS 0.90 2.00 12.00 7.20 3.80 3.75 87 Pazhikara 0.70 2.20 8.81 6.25 3.92 4.62 88 Perinad (Dw) 0.86 1.69 10.95 8.77 5.66 6.57 89 Puthoor 0.75 2.70 11.50 6.20 6.05 8.70 90 Quilon 0.88 0.00 9.67 8.57 6.80 7.28 91 Sasthamkotta 0.80 2.10 8.50 6.10 6.00 5.00 92 Tattamala 0.87 1.50 3.71 3.34 1.09 1.45 93 Thevalakkara 0.80 1.50 12.50 8.60 5.40 7.49 94 Ummannur 0.85 1.50 10.82 10.71 5.84 7.90 95 Vallikavu 0.70 1.90 3.70 2.20 0.44 1.50 96 Aalumpeedika 0.45 1.50 5.00 2.00 1.35 2.10 97 Adichanallur 0.66 1.70 6.54 5.44 2.36 2.48 98 Ambalamkunnu 0.65 1.90 11.10 10.90 6.47 7.57 99 Ashtamudiseri 0.85 1.07 2.55 2.08 1.66 1.75 100 Chakkuvalli(Sooranad) 1.00 2.80 20.00 16.90 12.40 11.48 101 Chavara-panmana 0.70 1.20 4.00 2.10 1.30 1.80 102 East Kallada 0.75 1.80 10.00 7.50 3.18 4.10 103 Kalluvadakkal 0.77 1.80 12.23 10.48 4.89 7.58 104 Karippira 0.75 1.90 10.80 10.25 6.95 8.48 105 Karuvel 0.79 2.13 12.26 11.86 7.44 8.79 106 Killikkallur 0.82 3.00 10.88 9.98 7.22 7.59 107 Killoor 0.67 1.35 7.78 6.47 4.38 4.83 108 Kottathala 0.75 1.50 14.00 13.00 7.95 8.20 109 Koyivila 0.72 1.60 9.35 8.62 2.38 3.73 110 Kundara 0.70 1.43 15.10 14.65 11.80 13.92 111 Kuttivattam 0.90 1.00 5.00 3.00 1.90 4.20 112 Minambalam 0.76 1.60 18.44 18.04 8.12 9.32 113 Miyannur 0.70 2.00 13.00 12.76 7.02 9.15

114 Mukhathala - Kaniyamthodu 0.68 1.15 5.52 2.57 1.02 1.27 115 Mukkunnapuram 0.72 2.64 5.90 5.34 1.22 1.98 116 Mumpuzha 0.87 1.70 7.56 6.48 5.90 6.13 117 Nedungulam 0.75 1.80 14.05 13.63 6.15 6.70 118 Neduvankavu 0.75 0.85 5.70 4.06 1.97 2.79 119 Nellikunnam 0.80 1.33 4.40 4.00 1.08 1.96 120 Nindakara 0.62 2.45 2.05 2.05 0.66 0.56 121 Panaveli 0.77 1.30 3.13 0.75 0.28 0.30 122 Paravur Tekkubhagam 0.83 1.35 5.22 4.25 3.87 4.10 123 Pavithreswaram Jn 0.80 2.00 12.00 10.00 8.70 9.40 124 Perumpuzha 0.89 1.57 16.16 15.84 6.40 10.41 125 Pudakulam 0.83 1.20 6.57 3.19 2.21 2.19 126 Roaduvila 0.80 2.00 11.00 10.45 5.22 6.77 127 Sankaramangalam 0.65 1.45 3.31 2.27 0.95 0.94 128 Tanni 0.58 0.90 3.92 3.23 1.38 1.59 129 Tekkumbhagam 0.66 2.00 9.19 8.26 5.29 5.28 130 Thirumullavaram 0.57 0.85 3.33 2.78 2.29 2.20 131 Vallikkeezhu 0.57 1.30 7.65 6.49 2.43 3.49 132 Vavvakkavu 0.50 2.00 7.00 2.80 2.00 4.80 133 Velamanur 0.80 1.85 9.20 8.72 6.95 7.41 134 Veliyam 0.60 2.00 9.30 7.70 2.40 4.17 135 Edavali 0.80 1.60 19.45 9.63 8.72 9.64 136 Kallambalam 0.38 2.10 9.72 8.64 5.74 7.46 137 Navaikulam 0.85 2.00 18.65 17.67 8.04 9.53 138 Palayamkunnu 0.40 1.65 21.90 15.90 8.55 10.63 139 Perumgulam 0.75 1.60 8.15 7.20 6.85 7.15 140 Varkala 0.74 1.89 16.76 16.20 12.99 12.70 141 Manambur 0.83 2.70 22.17 19.77 17.35 18.72 142 Muttanam 0.92 0.85 6.18 3.85 2.21 2.33 143 Nedumkanda 0.80 1.70 31.20 29.69 27.02 26.45

144 Pallikkal 0.80 1.52 13.83 13.60 8.07 10.96 145 Thalavilamukku 0.75 2.30 9.25 7.68 4.86 6.38 146 Tottakkadu 0.75 2.00 9.70 8.93 7.01 7.04 147 Vadaserikanam (Allanmoodu) 0.69 1.55 14.81 14.05 11.53 12.86 148 Adoor 0.70 2.50 15.00 12.20 10.50 11.55 149 Arnootimanalam 0.90 2.10 11.50 8.40 9.00 5.82 150 Churakkod 0.80 2.00 11.00 8.25 5.60 5.90 151 Kadambanad 0.75 1.80 8.50 4.30 4.55 4.25 152 Kulanada 0.80 3.20 12.50 10.20 6.85 9.35 153 Omallur 0.75 1.20 10.50 8.85 8.13 7.65 154 Paranthal 0.50 2.40 8.50 5.90 4.90 4.85 155 Thatta 0.60 1.20 4.20 2.00 0.54 1.20 156 Thumpamon 0.70 1.30 10.00 7.00 5.50 6.12 157 Mutoor 0.85 1.25 6.45 4.35 2.3 3.1 158 Peringara 0.67 1.1 5.87 2.25 0.87 1.45 159 Pulikeezh 0.75 1.12 6.36 3.05 2.05 2.75 160 Anadasramam 0.7 2.75 12 10.4 5.5 7.7 161 Arunoottimangalam 0.63 2.34 8.5 6.04 5.25 5.21 162 Ayamkudi 0.7 2.25 14.7 12.1 4.86 5.62 163 Changanassery 1.14 2.5 6.75 4.15 1.51 1.81 164 Edinillam 0.9 1.8 6.25 3.12 1.65 2.2 165 Ikarakunnam 0.78 2.1 11.7 10.46 5.9 6.78 166 Kaduthuruthi 0.53 2.85 8.55 7.47 2.35 4.37 167 Kottayam 0.71 3.19 14.7 13.05 9.17 9.21 168 Kumarakom 0.9 1.7 4.8 1.48 0.1 0.7 169 Palamkadavu 0.7 1.8 4.9 2.63 0.73 1.21 170 Pallam 0.75 1.8 10.75 8.82 4.77 4.99 171 Pulikuttiserry 0.75 1.82 3.85 1.78 0.33 1.23 172 Thalayolaparambu 0.8 2.5 9.5 6.05 1.8 173 Tiruvarppu 0.7 2.3 5.2 2 0 0.72

174 Vaikam 1.15 1.8 5.65 3.82 0.44 2.6 175 Vechur 0.8 1.1 3.85 2.73 0.9 1.22 176 Velloor 0.7 2.56 5.9 4.27 2.61 2.48 177 Udayanapuram 0.8 2.25 3.88 1.22 178 Bramamangalam 1.3 2.5 11 6.68 179 Chempu 0.65 1 3.88 2.02 180 Chengalam 1.2 1.2 3.8 0.22 2.15 181 Ettumanur 0.75 2.5 7.5 3.25 182 Kalathur 0.75 2.6 8.22 6.75 183 Kudavechur 0.7 1.75 3.73 1.56 1.92 184 Mannanam 0.8 2.75 9 5.98 185 Mevallur 0.8 1.5 6 2.7 186 Nindur 0.8 1.6 11.1 2.52

ANNEXURE-III DETAILS OF WATER LEVES FROM THE PIEZOMETER IN THE STUDY AREA MONITORED BY CGWB

Sl.NO LOCATION District WELL TYPE Longitude Latitude MP TOTAL DEPTH MAY 12 AUGUST 12 NOVEMBER 12 JAN 13 MAY 13 AUGUST 13 NOVEMBER 13 JAN 14 MARCH 14

1 Chalavara (Pz-1) Kollam Pz 76.534611 8.999639 0.80 0.0 18.77 17.64 18.25 16.76

2 Chalavara (Pz-2) Kollam Pz 76.534444 8.999639 0.80 0.0 14.12 13.8 13.64 14.09

3 Chalavara (Pz-3) Kollam Pz 76.534389 8.999556 0.80 0.0 1.06 0 0.06 0.69

4 Chalavara (Pz-4) Kollam Pz 76.534361 8.999500 0.80 0.0 4.4 3.15 3.01 3.53

5 Chettikulangara Alapuzha Pz 76.516600 9.225217 0.70 25.0 4.80 2.80 2.60 4.40 4.7 3.4 3.5 3.5

6 Edavali Kollam Pz 76.692389 8.768944 0.70 59.3 16.80 11.56 17.00 17.05 17.03 12.4 13.54 16.02 18

7 Kalluvathukkal Kollam Pz 76.746194 8.831889 0.80 0.0 5.23 5.89 3.12 4.36 5.04

8 Kattanam Alapuzha Pz 76.565450 9.177517 0.70 25.0 11.60 12.3 10 10.6 11

9 Krishnapuram North Alapuzha Pz 76.510000 9.150000 0.80 25.0 14.55 14.45 13.40 11.80 14.2 14.2 14.9 15.1

10 Krishnapuram South Alapuzha Pz 76.514183 9.151833 0.80 25.0 6.65 7.70 4.70 6.70 2.7 6.1 6.7 7.2

11 Manambur Kollam Pz 76.791333 8.732028 0.50 0.0 13.83 10.8 11.58 12.08

12 Manapalli Kollam Pz 76.574250 9.104317 0.70 25.0 17.22 16.50 11.70 15.8 15.2 11.9 17.6 12.34

13 Muthukulam Alapuzha Pz 76.449967 9.201467 0.70 25.0 0.95 0.45 0.15 0.7 0.45 0.3 0.3 1

14 Nallila (Pz) Kollam Pz 76.703083 8.927667 0.70 0.0 7.54 7.46 7.12 6.32 7.14 7.5 6.07

15 Pandalam Pta Pz 76.676700 9.224950 0.75 25.0 4.25 3.85 3.95 6 3.05 3.7 4.3

16 Parinad (Pz) Kollam Pz 76.637667 8.947583 0.70 0.0 25.30 37.30 37.3 35.47 36.62 34.8 34

17 Trikkadavur (Pz) Kollam Pz 76.598056 8.926000 0.00 0.0 14.55 12.02 11.84 13.78 15.66 7.1 11.18 14.3 15.45

18 Ummannur (Pz) Kollam Pz 76.820528 8.933250 0.70 0.0 11.20 12.88 15.52 7.19 9.54 10.63

19 Varakala-2 Kollam Pz 76.709361 8.735111 0.75 0.0 20.55 25.69 21.16 20.85 20.83 15.43 29.15 21.15 18.85

20 Varkala-1 Kollam Pz 76.709444 8.735333 0.70 0.0 17.90 18.16 16.50 18.40 18.29 19.53 16.3 17.8 18.27

21 Vayyankara Kollam Pz 76.626617 9.138267 0.60 25.0 14.71 17.00 15.23 16.65 15.6 15.6 17.48 17.95 15.33

Ezhupunna 22 ALAPUZHA PZ 76.280000 9.780000 0.70 1.8 1.01 1.65 2.54 1.18 1.04 1.6 1.6 (Kodanthuruthu)

23 Haripad - Central ALAPUZHA PZ 76.450000 9.280000 0.55 9.85 9.45 7.75 9.45 10.25 9.65 9.15 9.85 10.55

24 Haripad - North ALAPUZHA PZ 76.450000 9.280000 0.60 9.4 9.4 7.9 9.7 9.80 9.2 7.4 8.4 10.7

25 Haripad - East ALAPUZHA PZ 76.450000 9.280000 0.52 9.88 10.48 9.68 1.48 3.08 9.48 9.48 10.33

26 Haripad - South ALAPUZHA PZ 76.450000 9.280000 0.70 10.00 1.5 1.8 10.25

27 Haripad - West ALAPUZHA PZ 76.450000 9.280000 0.70 9.3 10.30

28 Kalarkode - Central ALAPUZHA PZ 76.330000 9.450000 0.75 2.45 1.85 1.75 2.75 3.55 2.23 3.34

29 Kalarkode - East ALAPUZHA PZ 76.330000 9.450000 0.80 2.6 4.2 5.4 3.2 3.40 2.28 3.38

30 Kalarkode - South ALAPUZHA PZ 76.330000 9.450000 0.90 2.1 0.5 0.9 1.6 2.10 0.1 1.09 0.2 2.07

31 Kalarkode - West ALAPUZHA PZ 76.330000 9.450000 0.80 5.9 3.6 4.4 19.97 20.22

32 Kallara KOTTAYAM PZ 76.477778 9.702778

33 Karumady ALAPUZHA PZ 76.380000 9.360000 0.60 3.2 1.19 1.19 1.96 1.79 2.15 2.04

34 Kumarakom KOTTAYAM PZ 76.438889 9.586111 2

Mannancherry 35 ALAPUZHA PZ 76.350000 9.560000 0.80 (Panch)

36 Mannar ALAPUZHA PZ 76.550000 9.580000 0.83 5.62 5.07 4.27 5.47 4.27 4.67 4.77 5.17 6.07

37 Preethikulangara - C ALAPUZHA PZ 76.300000 9.580000 0.86 12.63 12.98 13.48 12.77 13.02 13.14 12.99

38 Preethikulangara - S ALAPUZHA PZ 76.300000 9.580000 0.78

39 Tannirmukkom ALAPUZHA PZ 76.380000 9.660000 0.70

ANNEXURE-IV DETAILS OF GROUND WATER QUALITY OF SHALLOW AQUIFER.(NHS)

Sl. Location M.P DIA Depth Date of pH EC in TH as Ca Mg Cl F NO3 1 Alleppey Town(new well) 0.89 1.28 3.97 18.04.13 7.78 510 144 53 2.9 55 0.25 24 2 Aranootimangalam 0.90 2.10 11.50 18.04.13 145 30 8.8 2 20 0.17 0.59 3 Charummoodu(new well) 0.90 4.10 30.00 17.04.13 6.55 51 12 3.2 0.97 5.7 0.02 5.7 4 Chettikulangara 0.80 2.00 4.50 18.04.13 185 66 22 2.9 8.5 0.08 0 5 Idakkunnam 0.90 2.20 14.20 17.04.13 6.73 61 8 1.6 0.97 11 0 6 6 Kandiyoor 0.65 1.20 4.90 18.04.13 7.87 210 36 0 12 7 Kattanam 0.80 3.10 15.90 17.04.13 6.28 32 10 2.4 0.97 7.1 0.04 2.2 8 Kayamkulam 0.50 1.10 4.50 17.04.13 8.07 250 96 31 4.4 17 0.11 0.87 9 Kuzhamathu 0.90 2.10 16.00 17.04.13 6.68 108 14 3.2 1.5 23 0.04 14 10 Mannar (new well) 0.7 1.3 5.95 18.04.13 7.45 360 94 32 3.4 31 0.15 24 12

11 Mavelikara 0.60 1.40 4.50 18.04.03 7.66 210 80 26 3.4 19 0.01 12 12 Muthukulam(new well) 0.80 1.70 5.00 18.04.13 182 48 8 6.8 20 0.07 0.13 13 Nooranad 0.80 2.10 12.50 17.04.13 6.59 27 4 traces 0.97 5.7 0 0.84 14 Oachira 0.60 0.90 7.00 17.04.13 8.17 173 52 17 2.4 14 0.06 0 15 Pallarimangalam 0.80 1.50 3.60 17.04.13 7.66 168 78 27 2.4 5.7 0.07 0.8 16 Pattiyur 0.80 1.00 3.30 18.04.13 7.91 700 90 28 4.9 122 0.35 3.1 17 Thamarakulam 0.90 2.00 6.70 17.04.13 7.09 101 18 4 2 19 0 8.5 18 Vallikunnam 1.00 1.70 5.20 17.04.13 7.89 260 80 30 1.5 11 0 12 19 Venmani(Thazhakam) 0.90 2.00 4.50 18.04.13 8.17 220 76 14 10 14 0.27 0 20 Anchalummoodu 0.65 1.60 10.13 21.4.13 3.93 280 25 8 1.2 45 0.14 46 21 Azhathil 0.80 1.40 8.90 19.4.13 7.18 118 20 6.4 0.97 17 0.16 15 22 Chenkulam 0.75 2.35 6.55 20.4.13 7.39 77 12 3.2 0.97 11 0.14 2.7 23 Karunagapally 0.85 1.50 5.00 18.4.13 8.06 490 175 54 9.7 71 0.1 36 24 Kollam 0.88 0.00 9.67 21.4.13 7.78 650 200 70 6.1 89 0.12 131 25 Kottiyam 0.95 2.10 22.15 19.4.13 7.65 240 90 30 3.6 28 0.14 5 26 Kudavettur 1.20 2.10 8.19 18.4.13 7.8 210 55 14 4.9 24 0.16 15 27 Kulakkada 0.60 2.00 11.50 21.4.13 7.79 174 34 8.8 2.9 16 0.13 7.6 28 Kuripally 0.84 1.75 11.16 20.4.13 6.58 200 25 6 2.4 39 0.1 39 29 Nallila 0.90 1.70 8.90 19.4.13 3.01 230 15 traces 3.6 25 0.14 38 30 Nedungolam 0.80 1.60 10.90 18.4.13 7.75 118 8 1.6 0.97 24 0.1 6.4 31 Oyur 0.90 1.90 12.95 20.4.13 7.19 94 8 1.6 0.97 9.9 0.24 14 32 Paripalli 0.70 0.00 13.30 20.4.13 7.42 72 18 4 2 8.5 0.14 0.69 33 Pavitreswaram 0.90 2.00 12.00 2.4.13 7 107 8 1.6 0.97 20 0.04 7.5 34 Perinad 0.86 1.69 10.95 19.4.13 7.44 133 18 4.8 1.5 33 0.16 6.9 35 Sasthamkotta 0.80 2.10 8.50 18.4.13 8.27 310 95 32 3.6 43 0.27 3.9 36 Thattamala 0.87 1.50 3.71 21.4.13 7.41 370 90 24 7.3 57 0.14 24 37 Thevalakkara 0.80 1.50 12.50 19.4.13 7.3 110 22 7.2 0.97 19 0.07 1.8 38 Ummannur 0.85 1.50 10.82 18.4.13 7.9 220 50 10 6.1 26 0.11 15 39 Kottarakkara 0.80 2.02 18.27 20.4.13 7.63 190 30 7.2 2.9 37 0.06 15 40 Navaikulam 0.85 2.00 18.65 11.4.2013 8.04 310 46 12 3.9 57 0.1 15

41 Palayamkunnu 0.40 1.65 21.90 11.4.2013 8.17 188 56 21 0.97 18 0.16 0 42 Perumgulam 0.75 1.60 8.15 11.4.2013 7.63 148 18 4 1.9 27 0.12 12 43 Arunoottimangalam 0.63 2.34 8.5 12.04.13 7.55 42 10 0.8 2 7.1 0.1 4 44 Ettumanur 0.75 2.5 7.5 06.04.13 7.32 92 16 4 1.5 13 0.07 8.4 45 Ikarakunnam 0.78 2.1 11.7 06.04.13 7.6 114 18 3.2 2.4 20 0.16 15 46 Kaduthuruthi 0.53 2.85 8.55 12.04.13 7.38 159 28 7.2 2.4 26 0.2 16 47 Kalathur 0.75 2.6 8.22 12.04.13 7.02 48 12 2.4 1.5 8.5 0.15 8.2 48 Kottayam 0.71 3.19 14.7 07.04.13 6.95 45 8 1.6 0.97 9.9 0.16 5.5 49 Pallam 0.75 1.8 10.75 05.04.13 - 112 24 8 0.97 16 0.25 10 50 Pulikuttiserry 0.75 1.82 3.85 06.04.13 8.29 97 38 12 2 8.5 0.11 2 51 Tiruvarppu 0.7 2.3 5.2 06.04.13 - 300 44 14 2 44 0.18 5.9 52 Adoor 0.70 2.50 15.00 22.4.2013 6.2 91 6 1.6 0.97 11 0.1 7.6 53 Kadambanad 0.75 1.80 8.50 21.4.2013 8.47 340 62 21 2.4 64 0.58 0.35 54 Mutoor 0.85 1.25 6.45 20.4.2013 6.64 200 36 11 1.9 34 0.24 24 55 Pandalam 0.80 2.00 8.90 22.4.2013 7.36 67 20 3.2 2.9 8.5 0.19 3.1 56 Peringara 0.67 1.1 5.87 20.4.2013 8.82 140 40 6.4 5.8 18 0.37 0.87 57 Pulikeezh 0.75 1.12 6.36 20.4.2013 8.45 179 78 30 0.97 8.5 0.29 0 58 Thatta 0.60 1.20 4.20 22.4.2013 7.49 79 18 6.4 0.97 9.9 0.25 0.7 59 Alapuzha 0.89 1.28 3.97 26.02.13 8.45 320 150 57 1.9 8.5 0.06 2.2 60 Edathua 0.46 1.75 3.5 02.03.13 8.32 310 94 26 7.3 21 0.23 2.6 61 Harippad 0.78 1.21 4.55 26.02.13 8.14 290 82 26 3.9 44 0.04 5.6 62 Nedumudi 0.75 1.95 4.25 01.03.13 8.37 650 215 62 15 53 0.12 2.7 63 Neerkunnam 0.71 1.05 3.77 25.02.13 7.97 180 70 22 3.4 16 0.02 7.1 64 Pacha 0.5 1.6 3.7 02.03.13 8.46 640 135 28 16 107 0.19 19 65 Ramankari 0.32 1.3 3.3 01.03.13 8.23 280 90 28 4.9 27 0.15 5.1 66 Thakazhi 0.7 1.9 3.65 02.03.13 8.52 640 170 46 13 78 0.4 4

ANNEXURE-V DETAILS OF GROUND WATER QUALITY OF WARKALI AQUIFER. (CGWB AND KWA WELLS)

SL.N Fluori Calciu Magnesi Sodiu Potassi Carbon Bicarbon Sulfa Chlori Conducti Hardn samp O location Date de pH m um m um ate ate te de vity ess le 23-Apr- 7.5 SIDA 1 Arthungal 87 0.45 4 66 28 48 10 0 214 <0.01 181 870 280 EXP Cheppad 29-Jan- SIDA 2 58 6.9 169 466 1718 EXP Kandiyur 03-May- 7.9 SIDA 3 86 <0.01 6 17 3.3 3.6 0.8 0 61 <0.01 11 120 56 EXP Karunagapalli 27-Nov- 6.8 SIDA 4 85 0.14 9 24 4.9 4.2 1.8 0 91 <0.01 13 170 80 EXP 13-Mar- 7.3 SIDA 5 Karthikapalli 87 0.54 7 52 12 23 4.8 0 244 <0.01 40 460 180 EXP 04-Apr- 7.5 SIDA 6 Mancombu 87 0.27 1 52 28 340 13 0 134 15 717 2400 245 EXP 03-Feb- 6.9 SIDA 7 Muttom 87 0.48 5 64 16 53 3.9 0 159 7.5 156 710 225 EXP 04-Jan- SIDA 8 Shertallai 58 7.6 440 1135 3880 EXP 30-Jan- 7.4 SIDA 9 Thottappalli 87 0.65 4 48 16 30 8.3 0 299 0 14 480 185 EXP 30-Jul- 7.6 SIDA 10 Thottappalli 86 0.56 1 62 32 131 15 0 311 40 202 1220 285 EXP 02-May- 7.1 SIDA 11 Tirumullavaram 87 0.09 8 26 6.1 32 1.4 0 79 22 57 340 90 EXP 01-Dec- 7.1 SIDA 12 Ponana 85 0.3 6 72 12 8.6 4.4 238 <0.01 38 450 230 KWA 01-Dec- 6.8 SIDA 13 Edapallikota 85 0.3 9 26 4.9 7.8 3.8 122 1 13 200 85 KWA 01-Dec- 7.1 SIDA 14 Klappana 84 0.5 4 54 13 9.2 3.2 238 <0.01 18 380 190 KWA 01-Nov- 7.5 SIDA 15 Ayirantenga 85 5 59 12 9 4 323 <0.01 18 420 196 KWA 01-Feb- SIDA 16 Valiyazhikaltura 86 0.8 8 46 16 13 6 207 <0.01 32 400 180 KWA 01-Nov- 7.5 SIDA 17 Kayamkulam 85 4 47 9.8 17 49 220 11 380 158 KWA 01-Feb- 7.5 SIDA 18 Pattoli market 86 0.7 1 48 18 38 10 220 <0.01 71 540 195 KWA 01-Feb- SIDA 19 Pattiyur 86 0.7 7.7 48 15 15 8 232 <0.01 14 390 180 KWA 01-Feb- SIDA 20 Arattupuzha 86 0.01 8.3 36 16 27 8 213 <0.01 11 390 155 KWA

01-Mar- 7.8 SIDA 21 Pallipad 86 0.7 5 32 21 19 7.9 190 <0.01 39 430 165 KWA 01-Jan- 7.4 SIDA 22 Kottarkaitha 87 0.7 2 42 12 13 4.8 220 0 7.1 348 155 KWA 01-Jan- 7.2 SIDA 23 Chellakkad 87 0.9 8 26 13 34 8.5 220 0 5.3 365 120 KWA 01-Jan- 7.4 SIDA 24 Pallana 87 1 7 58 29 58 14 195 0 181 829 265 KWA 01-Jan- 7.0 SIDA 25 Kumarakodi 87 1.1 5 30 13 24 7.8 220 0 7.1 357 130 KWA 01-Jan- 7.3 SIDA 26 Kuruvalla 87 1.2 3 44 19 22 6.9 244 0 8.9 385 190 KWA 01-Jan- SIDA 27 Purakkad 87 1.3 7 30 12 36 9.5 232 0 11 418 125 KWA 01-Jan- 7.5 SIDA 28 Illichhira 87 1.4 3 48 22 32 10 257 <0.01 57 570 210 KWA 01-Jan- 7.5 SIDA 29 Tagazhi 86 0.5 4 32 8.5 54 13 244 <0.01 34 490 115 KWA 01-Jan- 6.9 SIDA 30 Pullangadi 86 0.8 9 36 17 50 11 261 <0.01 64 600 160 KWA 01-Apl- 6.8 SIDA 31 Vaisyaabaga 87 0.02 2 26 18 44 232 1.5 60 1 590 140 KWA 01-Apl- 6.7 SIDA 32 Kanjirapada 87 1.3 6 50 19 56 12 201 0 117 768 205 KWA 01-Apl- 6.6 SIDA 33 Charapakulam 87 1 4 30 13 80 12 287 <0.01 57 670 130 KWA Charapakulam 01-Apl- 6.6 SIDA 34 east 87 1 6 30 12 78 12 317 <0.01 50 646 125 KWA 01-Mar- 7.4 SIDA 35 Neduaudi temple 86 5 38 13 50 10 146 <0.01 103 580 150 KWA Neduaudi temple 01-Apl- 6.6 SIDA 36 office 87 0.9 8 40 19 100 14 256 <0.01 156 936 180 KWA 01-Apl- 3.2 SIDA 37 Mancombu 87 0.6 5 44 16 73 10 213 <0.01 149 780 175 KWA 01-Apl- 6.3 SIDA 38 chenanari 87 0.3 1 82 12 41 11 274 <0.01 96 745 255 KWA 01-Jan- 7.1 SIDA 39 Chenbupura 86 1 5 38 15 126 14 262 <0.01 181 970 155 KWA 01-Apl- 6.5 SIDA 40 Pallathuruthi 87 1.4 3 14 9.7 62 10 207 <0.01 32 470 75 KWA 01-Dec- 7.2 SIDA 41 TDMC Alleppey 85 1.5 4 16 9.7 69 11 235 <0.01 20 450 80 KWA 01-Jan- 7.2 SIDA 42 Milk Plant 87 1.6 1 14 12 65 11 262 0 11 419 85 KWA

01-Jan- 7.3 SIDA 43 Chudukad 86 1.9 9 10 6.1 82 8 249 <0.01 17 460 50 KWA 01-Jan- 7.4 SIDA 44 Pazhavangadi 87 1.3 8 30 16 106 12 305 0 103 728 140 KWA chandanakavu 01-Jan- 7.4 SIDA 45 north 87 1.6 4 20 12 80 11 287 0 39 539 100 KWA chandanakavo 01-Jan- 7.2 SIDA 46 south 87 2.6 6 20 15 170 15 317 <0.01 156 940 110 KWA 01-Jan- 7.4 SIDA 47 vellakinar 87 1.4 2 28 12 90 10 299 0 53 612 120 KWA 01-Jan- 7.5 SIDA 48 vazhichery 87 1.3 2 22 13 104 11 296 0 82 673 110 KWA 01-Jan- 7.3 SIDA 49 Mannanchery 86 0.6 6 84 85 480 33 220 <0.01 1050 3700 560 KWA 01-Jan- 8.1 SIDA 50 Kalavoor 86 1 7 20 20 153 17 244 24 170 1000 136 KWA Maramkulama 01-Jan- 7.4 SIDA 51 dsouth 87 2.1 8 8 7.3 100 10 293 0 43 534 50 KWA 01-Jan- 7.1 SIDA 52 Kanzikuzhi 87 0.5 9 120 83 192 28 189 5 664 2230 640 KWA

ANNEXURE-VI DETAILS OF GROUND WATER QUALITY OF VAIKOM AQUIFER. (CGWB AND KWA WELLS)

SL.N Fluori Calciu Magnesi Sodiu Potassiu Carbona Bicarbon Sulfa Chlori Conductiv Hardne O Location Date de pH m um m m te ate te de ity ss sample Arunuthimanga 29-Jan- 7.1 SIDA 1 lam 87 0.41 4 80 6.1 15 6.3 0 317 0 7.1 450 225 EXP 01-Oct- 7.1 SIDA 2 Ittikara 86 0.74 1 40 8.5 53 5 0 222 <0.01 46 500 135 EXP 09-Dec- 8.8 SIDA 3 Kalarkod 85 2.8 3 18 45 1800 70 48 102 <0.01 2900 8800 230 EXP Kandiyur 14-Aug- 7.6 SIDA 4 86 0.3 3 76 9.7 52 8.5 0 342 <0.01 51 670 230 EXP 22-Mar- 7.4 SIDA 5 Karthikapalli 87 0.74 6 46 8.5 53 9.6 0 305 <0.01 33 520 150 EXP 14-Mar- 7.9 SIDA 6 Kollurvilla 86 0.98 1 30 6.1 74 10 0 154 45 75 580 100 EXP 17

08-Jan- SIDA 7 kidangara 75 7.6 46 90 113 700 2580 485 EXP Mainagappalli 01-Apr- SIDA 8 72 12 11 5 0 195 0 14 197 75 EXP 01-Mar- SIDA 9 Mayyanad 57 7.9 169 13 350 EXP 28-Jan- SIDA 10 Muttom 87 0.63 6.5 56 11 54 7.7 0 348 <0.01 27 560 185 EXP Nallanickal 04-Jul- 7.7 SIDA 11 86 1.24 3 52 51 240 20 0 378 55 398 1840 340 EXP 26-May- SIDA 12 Pannimasseri 72 28 17 12 <0.01 3 122 0 35 401 140 EXP 10-Jun- SIDA 13 Parumala 75 30 4.1 171 53 92 EXP 29-Nov- 7.5 SIDA 14 Pattanakad 85 2.05 1 42 8.5 500 15 0 329 56 662 2600 140 EXP Sooranadu 01-Mar- SIDA 15 72 20 12 10 <0.01 0 128 0 7 208 99 EXP 27-Mar- SIDA 16 Thrikkaruva 87 12 14 9.5 <0.01 0 282 0 14 394 88 EXP Tirumullavara 08-May- 7.2 SIDA 17 m 87 1.19 4 16 6.1 84 3.8 0 238 30 26 490 60 EXP 17-Jan- SIDA 18 Udayanapuram 75 8.5 28 21 12 159 275 156 EXP Vetticode 24-Feb- SIDA 19 75 50 5.1 0 211 7 500 146 EXP 01-Aug- 6.1 SIDA 20 Soornad south 84 5 4 1.2 2.6 <0.01 6 4 30 15 KWA 01-Dec- 7.0 SIDA 21 Alappattu tura 85 0.6 1 64 8.5 18 7.2 281 <0.1 10 420 195 KWA 01-Dec- 7.0 SIDA 22 Alankadavu 85 0.6 4 64 11 19 8 287 <0.01 10 430 205 KWA 01-Aug- 6.5 SIDA 23 Puthiakavu 84 3 30 1.2 4.2 1.4 98 <0.01 8 160 80 KWA 01-Dec- 7.2 SIDA 24 Alampidika 85 0.5 2 50 9.8 8.6 2.7 201 <0.01 18 340 165 KWA 01-Dec- 7.1 SIDA 25 Pudupalli 85 0.01 3 62 12 38 8.1 335 <0.01 12 500 205 KWA 01-Feb- SIDA 26 Mangalamtura 86 0.6 8.1 48 15 13 4.4 226 0 7 370 180 KWA Nangiarkulanga 01-Jan- 7.3 SIDA 27 ra 87 0.4 7 66 7.3 13 2.8 152 <0.01 67 437 195 KWA 01-Dec- 6.9 SIDA 28 vezhapra 85 0.8 7 74 23 298 24 287 <0.01 462 1840 280 KWA

01-Jan- 6.7 SIDA 29 Velianad 86 0.7 1 42 16 430 20 213 15 675 2400 170 KWA 01-Jan- 6.5 SIDA 30 Kavalan 86 3 44 10 490 15 201 <0.01 750 2600 150 KWA 01-Apl- 6.5 SIDA 31 Kuttamangalam 87 1.3 2 54 19 630 20 421 35 934 3520 215 KWA 01-Jan- 7.3 SIDA 32 R.Block 86 0.8 4 60 13 470 2 445 17 600 2500 205 KWA 01-Jan- 7.7 SIDA 33 Kayapuraa 86 1.4 6 52 22 660 20 348 49 1040 3800 220 KWA 01-Jan- 7.4 SIDA 34 thaikal 86 0.3 8 104 56 135 18 116 23 511 1800 490 KWA 01-Jan- 7.2 SIDA 35 Pashakulam 87 1.6 7 38 15 460 14 268 48 621 2220 155 KWA 01-Jan- 7.3 SIDA 36 tanniraukam 87 1.2 6 38 18 256 22 226 30 373 1450 170 KWA 01-Jan- 8.2 SIDA 37 vayalar 86 1.9 1 20 9.7 326 18 438 21 376 1700 90 KWA 01-Jan- 8.3 SIDA 38 Ponnamveli 86 1.3 6 36 12 400 60 318 40 511 2200 140 KWA 01-Jan- SIDA 39 Kuthiathode 86 0.9 8 68 20 720 70 416 42 1050 3800 250 KWA 01-Jan- 7.1 SIDA 40 aroor 86 0.5 5 100 56 450 70 232 <0.01 873 3100 480 KWA

ANNEXURE VII: DETAILS OF VERTICAL ELECTRICAL SOUNDING IN STUDY AREA

Sl. No Location AB/2 in m Layers Thickness Depth to Remarks Massive Roh 1 Roh 2 Roh 3 Roh 4 Roh 5 Thickness Thickness Thickness Thickness Thickness formation 1 2 3 4 5

1 Krishnapuram 120 1000 650 30 VH 4.5 6.5 29.0 40 Allu

2 Puthiyakavu 120 600 70 50 1.2 18.8 Ext. Allu

3 Karipuzha 180 650 80 11 50 1.2 8.8 48.0 Ext. Allu

4 Thiruvallavaram 90 750 120 50 120 1.2 8.8 10.0 Ext. Allu

5 Chavara 100 1600 200 10 VH 1.2 8.8 38.0 48 Allu

6 Kollam 150 6500 1300 45 VH 10.0 5.0 40.0 55 Allu

7 Pozhikkara 120 370 60 11 5.5 4.5 Ext. Allu

8 Kuttitheruvu 70 3000 650 25 3.5 6.5 Ext. Allu

9 Thazavu 120 1000 130 26 1.2 11.8 Ext. Allu

10 Kuttivattam 80 450 200 300 85 1.2 3.3 7.5 Ext. Allu

11 Tekkumbakam 100 900 350 48 5.0 17.0 Ext Allu

12 Noornad 90 3500 800 60 1.2 14.8 Ext. Ter

13 Charummood 80 980 500 47 1.2 8.8 Ext. Ter

14 Kattanam 150 480 100 25 4.0 5.0 Ext. Ter

15 Vayyankara 140 950 300 140 1.2 24.8 Ext. Ter

16 Sasthamkotta 150 10000 550 40 VH 2.0 12.0 34.0 48 Ter

17 Mainagapalli 70 330 40 180 7.0 38.0 Ext. Ter

18 Chakkuvalli 100 1000 350 255 3.0 7.0 Ext. HR

19 Kadambanad 100 750 70 40 150 1.2 10.8 28.0 Ext. Ter

20 AKKulangara 180 330 60 210 3.0 20.0 Ext. Ter

21 Arunattimangalam 120 850 150 23 1.2 8.8 Ext Ter

22 Kundara 60 520 80 12.0 Ext. Ter

23 Perinod 180 650 300 30 8.0 17.0 Ext. Ter

24 Ashtamudiseri 180 50 13 5 1.8 8.2 Ext. Ter

25 Kannanalloor 150 400 120 450 4.2 10.8 Ext. Ter

26 Mukhathala 180 2000 400 20 80 1.4 8.6 35.0 Ext. Ter

27 Pudukulam 180 2000 700 120 200 2.7 5.3 30.0 Ext. Ter

28 Meenabalam 180 550 200 30 VH 9.0 13.0 98.0 120 Ter

29 Parippalli 150 550 115 270 6.0 34.0 Ext. Ter

30 Adichanalloor 180 1200 300 58 1.5 3.5 Ext. Ter

31 Adoor 180 1600 600 190 300 2.5 6.5 46.0 Ext. HR

32 Enathu 120 800 230 450 5.0 35.0 Ext. HR

33 Mavady 120 1200 200 90 260 2.0 7.0 14.0 Ext. HR

34 Thumpanam 120 4800 750 100 VH 2.0 7.0 63.0 70 HR

35 Pandalam 120 700 100 34 200 3.0 3.0 18.0 Ext. HR

36 Ezhukone 180 220 80 150 300 VH 1.8 6.2 20.0 122.00 150 HR

37 Nellikunnam 180 300 230 470 6.0 9.0 Ext. HR

38 Oyoor 200 2000 70 160 VH 2.0 16.0 112.0 130 HR

39 Navaikulam 150 1700 250 140 300 1.5 4.5 22.0 Ext. HR

40 Cheriyavelunallur 120 1400 300 690 1.5 8.5 Ext. HR

ANNEXURE-VIII: DETAILS OF GROUND WATER EXPLORATION IN SEDIMENTARY ROCKS IN THE STUDY AREA

SL. LOCATION DISTRICT R.L DEPTH DEPTH T DISCH SPECIF EC SWL ALLUVI LATERI WARKA QUILO VAIKO ALAPU BASEME NO DRILL CONSTR ARGE IC UM TE LI N M ZHA NT ED UCTED (LPM) CAPAC THICK THICK THICK THICK THICK THICK ITY NESS NESS NESS NESS NESS NESS 1 Alisserey ALAPUZHA 3.789 247.5 122 NA 90 NA 490 55 0 75 117 Not Encont ered 2 Arthungal ALAPUZHA 1.5240 444.9 103 221 669 118.9 870 1.88 28.7 33 96 75 21 442.7 3 3 Aryad ALAPUZHA 4.1660 400.1 160 47 14 131 71 137 4 Chandirur ALAPUZHA 2.2570 180.4 180 47 49.6 50 146.6 0 5 Changanache ALAPUZHA 1.4480 35.6 638 0 7.31 0 24.69 0 35.66 ri 6 Arunuthiman ALAPUZHA 104 81.5 NA NA NA NA NA 19 80 99 galam 7 Cheppad ALAPUZHA 2.440 123.3 Nil NA 1074 NA 171 2.82 45.8 77.4 195/29 . 8 3 8 Haripad ALAPUZHA 2.130 55 54 27.6 720 53.8 509 3.17 26 6 23 9 Kalarkod ALAPUZHA 3.006 601 430 298 860 56.4 23.6 139.5 106.1 169.4 106 0 10 Kallara ALAPUZHA 1.955 37.5 0 113 0 12.19 0 0 24.39 0 36.58 0 11 Kandalur ALAPUZHA 132.7 95 871 1254 1390 460 4.65 26 0 66.5 40.2 12 Kandiyur ALAPUZHA 5.360 188.9 148 197 822 145.3 670 1.2 7 21.7 33 123 184.7 3 13 Karthikapalli ALAPUZHA 3.120 450 88 28.23 300 38.75 530 19.7 42 63 92 165 68 14 Karumadi ALAPUZHA 1.150 437.0 329 3476 1318 275.9 310 3.85 58 13 91 66 136 70 434 8 0 m agl 15 Kayamkulam ALAPUZHA 5.200 106.8 65 NA 1380 NA 280 9.07 16 8 46 36.8 16 Karuvatta ALAPUZHA 3.036 428.2 368 3855 1609 238.0 160 4.29 49.5 14 104 124 180 7.2 4 0 m agl 17 kidangara ALAPUZHA 1.670 97.14 97.14 258 39.6 51.8 91.4 0 18 Kottaram ALAPUZHA 3.281 326 172.5 3000 156 1.26 10.7 110.3 121 97 23 322 22

19 Krishnapura ALAPUZHA 6.248 317.9 295 134 825. NA 200 4.65 13.5 6.2 29.3 84 184.9 306 m 6 20 Mancombu ALAPUZHA 1.110 258.5 70 279 42.6 168 230 2.66 21 15.5 57 46.5 112.5 0 252.5 0 3 21 Mannancherr ALAPUZHA 3.895 202.7 199 142. 228 5.58 43.72 15.97 49 15.94 78.1 y 8 22 Muttom ALAPUZHA 2.480 274.7 253 296.5 360 207.8 560 Aflow 13.65 9.95 48 32.1 147 250.7 5 23 Nallanickal ALAPUZHA 1.896 391 206 36.23 412. 22.67 700 2.74 37.65 33 65 24.35 231.0 2 6 24 Nirkunnam ALAPUZHA 2.520 600.7 54 14 137 116 192 87.8 25 North ALAPUZHA 3.756 357.4 185 6 13 108 32 160 0 356 Mararikolam 0 26 Parumala ALAPUZHA 6.275 105.8 82.55 125 1324 198 663 4.95 12.2 6.1 60.9 79.2 . 27 Pattanakad ALAPUZHA 0.905 274.3 214.3 97.5 756. 28.5 230 3.43 60.9 42.7 74.7 90 268.3 6 0 28 Pattiyur ALAPUZHA 3.232 254.6 90 NA 300 NA 390 4 7 87 88 68.6 29 Ramankari ALAPUZHA 0.882 116.9 113 6.07 54 4.34 250 0.8 m 56.6 35 25.5 116 0 agl 30 Shertallai ALAPUZHA 4.663 237 574 33.75 18.6 79.35 55.8 49.5 7 31 Thakattusseri ALAPUZHA 5.090 127.4 165 14.6 6.71 18.9 23.7 48.7 112.61 0 32 Thakazhi ALAPUZHA 304 30.5 30.5 73 65 71 270 33 Thottappalli ALAPUZHA 1.252 269.4 174.14 413 2955 141.5 122 1.24 41 45.5 111.3 71.6 7 0 34 Thrikunnapu ALAPUZHA 1.145 600 209.2 37.7 74.6 78.95 92.75 238 78 zha 35 Thuravur ALAPUZHA 2.672 222.8 45 320 1.55 38 8 20 78 52.7 218.7 0 36 Vetticode ALAPUZHA 6.955 96.9 88.4 140 1059 85.07 500 1 6.1 6.1 3 6.1 70.1 91.4 37 230 Chavara KOLLAM 1.545 189 185 20.6 180 113 00 12.91 29 0 59 56 45.53 38 Ittikara KOLLAM 19.82 76 53 NA NA NA 500 15.73 18 0 0 53 71 39 Kannanallore KOLLAM 29.800 67.21 NA NA NA NA NA 14.02 0 0 28.04 42.06 40 Karunagapall 4.373 304 271 NA NA NA NA 2.9 16.5 46.5 61 180 i KOLLAM 41 176.3 Kollurvilla KOLLAM 8.852 250 190 NA 580 37.75 29.33 0 0 5 243.43 42 Slim Kottangara KOLLAM 13.75 35.05 NA NA NA 770 hole 7.01 0 0 17.98 24.99

43 Mainagappall 8.060 196.5 175 467 3414 239 197 3.08 0 14.02 28.04 140.8 182.88 i KOLLAM 9 6 44 Maradurkula 0.303 416 323 7.53 156 9.1 170 5.1 7.7 12.8 38.5 102 223 32.5 ngara KOLLAM 45 652. Mayyanad KOLLAM 137.6 ABD NA 2 48.4 500 ABD 9 3.3 0 28.9 96.4 46 Pallickal KOLLAM 25.920 30.1 28.5 NA NA NA NA 8.12 3.1 25.3 28.4 47 Pannimasseri KOLLAM 9.750 107.9 100.58 107 700 45 401 3.71 1.2 5.8 0 14.02 80.16 101.2 48 129.5 Slim Poodakulam KOLLAM 36.070 4 NA NA NA NA NA hole 3.96 11.06 0 67.01 45.15 126.18 49 Poruvazhi KOLLAM 26.273 47 32 11.8 45 5.8 60 7.62 29.8 50 Sasthamkotta 17.830 178.9 Nil NA NA NA NA Slim 13.11 161.8 174.95 KOLLAM 2 hole 4 51 Sooranadu KOLLAM 14.321 99.97 92.8 529 2211 157 208 1.63 7.01 88.08 95.09 52 189.8 2577 129.1 Thrikkaruva KOLLAM 9.110 9 184.29 184 .6 160 394 8.6 3.96 28.04 28.04 6 189.2 53 Tirumullavar 472. am KOLLAM 3.979 328.7 300 69.28 8 32.7 490 12.04 10.7 18 24.3 28 184 54 THIRUVAN very Edavali DRUM 1.178 121.9 109 NA low NA NA NA 7 12 40 32 113 0 55 THIRUVAN 378. Varkala DRUM 28.820 75.3 69 232.4 6 NA 70 49.93 0 7 63.75 4.55 0 0 56 Kulashekara 192 mangalam KOTTAYAM 4.082 54.86 5 6.1 0 12.2 12.2 15.2 0 45.7 57 108. 300 Kumarakom KOTTAYAM 1.178 169 127 6 0 0.62 44 0 0 0 125 0 169 58 Payarattubag 200 am KOTTAYAM 1.475 91.44 0 0 0 0 0 33.53 0 76.2 59 Udayanapura 919. 169 m KOTTAYAM 1.414 69.5 67.97 34.06 8 72.5 0 2.16 9.1 8.2 0 0 48.5 0 66.8 60 PATHANAM 40.970 88 70 530 1005 326.4 630 4.65 22.7 0 0 0 65.2 0 87.9 Pulikeezhu THITTA 5 0

ANNEXURE-IX: DETAILS OF GROUND WATER EXPLORATION IN HARD ROCKS IN THE STUDY AREA

DEPT DEPT H OF DISCH SP.C H CONS AHAG APA SL. DRIL TRUC E CIT SW ZONE NO LOCATION DISTRICT LED TION T S LPM Y EC L ENCOUNTERED ZONE TAPPED PATHANAMT 1 Adur Ew HITTA 123 21 330 35-36 35-36 Ambalattumbha N N 2 gam KOLLAM 301.89 A A 1800 NA 25.9 NIL NIL 3 Idakkattu KOLLAM 200.53 3 150 1050 1.3 10,45,90,142 10,45,90,142 N N 4 Karamkode KOLLAM 200.5 43.9 A A NIL NA NA 18.2 NIL 12.37,23.61,53.75,6 5 Kottarakara KOLLAM 114.71 31.97 51 1380 230 0.5 5.37 Khanjikuzhi 6 E/W KOTTAYAM N N 7 Kundara KOLLAM 206.15 45.15 A A NA 51 Dry Dry PATHANAMT 200 16 8 Mamood Ew HITTA PATHANAMT 1. 9 Mudiyurkonam HITTA 244.22 16.5 11 240 670 3.9 12,21,45,210 12,21,45,210 1. 10 Nellikunnam KOLLAM 200 4 17 72 140 2.86 45,80 45,80 11 Perumbaikadu KOTTAYAM THIRUVANDR 12 Thottakkad UM 200.53 4.4 NA 460 20.4 ALAPUZHA 0. 13 Vettiyar 229.1 65 108 400 15.5