Agniyar Basin

Introduction

The Agniyar river basin is situated between latitudes 09o55’00’’-10 o45’00’’ N and longitudes 78o15’00’’ - 79o 30’00’’E and is located in the middle part of on the coastal side. In this basin, there are 3 prominent rivers namely Agniyar, Ambuliyar and South Vellar with small streams. The north and western part of Agniyar basin is occupied by Cauvery river basin, south by Pambar and Kottakaraiyar river basin and east by Palk Strait and Bay of Bengal. The total geographical area of Agniyar basin is 4663.04 Sq.Km. It falls in the Survey of degree sheets 58‘J’, 58 ‘N’ and 58’O’’ on 1:250,000 scale covering part of , , Trichirappalli and a portion in Sivagangai and districts. The administrative setup of the Agniyar river basin is given below.

Sl.No. District Taluk Block Block/Area falling within the basin area in Sq.Km.

1 Trichirappalli Manaparai Marungapuri 330.41 2 Trichirappalli Manaparai Manaparai 3.52 3 Pudukkottai Aranthangi 370.71 4 Pudukkottai Alangudi Thiruvarankulam 305.53 5 Pudukkottai Alangudi Karambakudi 256.81 6 Pudukkottai Pudukkottai Pudukkottai 338.55 7 Pudukkottai Avudaiyarkovil Manamelkudi 250.89 8 Pudukkottai Avudaiyarkovil Avudaiyarkovil 161.58 9 Pudukkottai 133.81 10 Pudukkottai Thirumayam Thirumayam 80.77 11 Pudukkottai Thirumayam 220.03

Sl.No. District Taluk Block Block/Area Falling Within The Basin Area in Sq.Km.

12 Pudukkottai Kulathur Annavasal 365.05 13 Pudukkottai Kulathur 18.01 14 Pudukkottai Kulathur Kunnandarkoil 260.45 15 Pudukkottai Gandarvakottai 245.00 16 Thanjavur Orathanadu Orathanadu 116.00 17 Thanjavur Peravurani 343.99 18 Thanjavur Peravurani Sethubhavachattiram 275.59 19 Thanjavur Pattukottai Pattukottai 218.65 20 Thanjavur Orathanadu Thiruvonam 173.55 21 Thanjavur Thanjavur Thanjavur 116.27 22 Sivagangai Sakkottai 0.28 23 Sivagangai Thiruppathur Semmampattipudur 65.46 24 Dindigul Natham Natham 12.13 Total 4663.04

Physiography

Agniyar basin is one of the seventeen major river basins of Tamilnadu. It is a cone shaped or triangular basin located almost in the middle and eastern side of Tamilnadu. It falls in the Survey of India Toposheets of 58 /J, 58 / N and 58 / 0 in the Latitude from 90 55’00” to 100 45’00” and longitude from 780 15’00” to790 30’ 00”. Agniyar basin is embedded in between Cauvery basin in the north and northeastern side and Pambar Kottakkaraiyar basin in the south. In the southeastern side it is bordered by the Palk Strait and Palk Bay. Hence it has a small coastal stretch in the southeastern side.

Administrative boundary wise, it spreads in part of Pudukkottai, Thanjavur and Trichy districts and with a small extent in Sivagangai and Dindigul district.

The western half of the basin is hard rock terrain and the eastern half of the basin is sedimentary terrain. The landforms are observed as erosional and depositional regimes along with the fluvio marine regime in the eastern coastal part.

Physiographically this basin is divided into three regions viz, hilly region in the western fringes of the basin, pediplain region in the middle part of the basin and the coastal region in the eastern side of the basin.

Generally Agniyar basin is gently an undulating terrain sloping towards east – southeast direction. The slopes vary in the pediment and pediplain regions from 20 to 40 and 10 to 20 respectively, and in the flood plain, the slope is less than 1 0 to 20 and in the coastal plain area the slope is less than 10.

Geology Most of the area in Agniyar river basin is a gentle undulating terrain with dissected hill ranges occupying the west and central portion. The quartzite and charnockite forms many of the hill ranges while gneissie and sedimentary rocks occupy the plain. The important drainage systems are Agniyar, Ambuliyar and South Vellar rivers.

The basin area is traversed by crystalline rocks of Archaean and Proterozoic age and Sedimentary rocks of Miocene and Quaternary sediments. The oldest group of rocks recognized is the khondalite group comprising Garnetiferous Silliminite gneiss with or without graphite, quartzite and calc gneiss. The charnockite group of rocks comprises charnockite and their pegmatoidal variants, Pyroxene granulite and migmatite quartzite. The khondalite and charnockite group of rocks occur closely associated with each other and intricately co- folded. The pink granite is occuring an intrusive body in the country rock migmatite complex of proterozoic age.

The eastern part of the study area is covered by hard laterite and lateritic soil within which isolated patches of sand stone is found to occur. The south eastern part of the study area is covered by fluvial, fluvio marine and marine sediments of quaternary age. The fluviual deposits of sand, silt, and clay in an admixture of varying degree occur along Agniyar, Ambuliyar and South Vellar. They comprise levee, channel bar, point bar, back swamp and palaeo channels etc. The marine deposits are made up of fine to medium sands and black clays.

The tertiary formation are represented by Cuddalore sand stone. The Eastern part of the study area is occupied by Cuddalore sand stone of Mio-Pliocene age and shows pebbly sand stone and clay stone, generally with thick lateritic cover. The sand stone formations are of good aquifers. The Geological formation of Agniyar basin is shown in figure 1.

Figure 1 Geological formation of Agniyar basin

Landuse

IRS P6 LISS III imagery of March 2004 was used and interpreted visually for classification of different landuse categories under level I classification in the basin area. These landuse categories were further divided into different landuse features under level II classification. The land use map of Agniyar basin is shown in Figure 2.

The spatial distribution of landuse has been analysed through GIS techniques and furnished in the Table 2.7.3

Table. 2.7.3 Spatial distribution of landuse

Landuse Categories

Sl. Area in Sq.Km.. Percentage Level I Level II No. 1 Built up land Towns, Villages, industries, roads 44.99 0.96

2 Agricultural land 842.76 18.07 land Dry crop land 312.23 6.70

Plantations Cashew nut and Eucalyptus 75.90 1.63

Casuarinas 12.39 0.27

Grooves 143.96 3.09

3 Forest land Forest covered by scrub 181.05 3.88

Land affected by alkalinity 253.77 5.45

Land with scrub 113.41 2.43

Land with shrub 57.71 1.24

Barren land 1653.56 35.40 4 Wasteland Barren out crop 870.30 18.66

Land covered by Juliflora 5.71 0.12

Barren sand 4.35 0.09

Salt pan 5.19 0.11

5 Water bodies River, canal and tanks 85.76 1.84

Total area 4663.04 100.00

Fig. 2 Land use map of Agniyar Basin

Geomorphology Geologically this basin is occupied by both sedimentary and hard rock. The eastern part of the basin is covered by sedimentary formations with marine landforms where as the western part is covered by hard rock terrain, which exhibits denudation landforms. A detailed geomorphological study was carried out in the Agniyar basin and the landforms have been analysed based on the interpretation of image characteristics like tone, texture, shape, and pattern and associated features etc. IRS 1D False Color Composite imagery acquired in the month of January 2004 was used to classify the geomorphic units. Qualitative assessment was made for targeting groundwater potential available with each geomorphic unit. The geomorphology map of Agniyar Basin is shown in figure 3.

Figure 3 Geomorphology map of Agniyar Basin

Soil

The soils of Agniyar river basins have been shown in Figure 4. The major soil in this basin belongs to Alfisols, Vertisols and Entisols.

Figure 4 Soil map of Agniyar Basin Demographic And Social Characteristics

Population trend and population dynamics are important indicators of future water requirement. So also, the social characteristics of the population such as literacy level, level of housing, electrification, in house facilities, urbanisation trend are having indirect bearing on water planning. Land utilisation pattern, size of land holdings, nature of agricultural employment and industrial employment also would reflect on the water requirement of the population. An analysis of all these parameters, with reference to Agniyar river basin is described hereunder. Population Size: Urban and Rural

The Agniyar basin covers five districts namely Pudukkottai, Thanjavur, Trichy, Sivagangai and Dindugul districts. The sub basin wise population is given in Table 4 below. The Urban and Rural Population as per Census 2001 (in Million) Urban Rural Total Sl. Population Population Population No. Name of the Sub basin in Million (2007)

1 South Vellar 0.210 0.595 0.805

2 Ambuliyar 0.068 0.239 0.307

3 Agniyar 0.138 0.685 0.823 Total 0.416 1.519 1.935

Population Density

The population density is the highest in Ambuliyar sub basin (428 Persons per Sq.Km.) and the lowest is at South Vellar sub basin (396 Persons per Sq.Km.).

Sl. Name of the sub Area Total Population Density basin No (Sq.Km.) in Million Persons / Sq.Km.

1 South Vellar 2033.68 0.805 396

2 Ambuliyar 717.81 0.307 428

3 Agniyar 2057.86 0.823 400

Total 4809.35 1.935 402

Hydrometeorology Rainfall Raingauge Stations Agniyar basin has an area of 4663.04 Sq.Km. spread over in four Districts namely Pudukkottai, Thanjavur, Trichy and Dindigul.

Considering the distribution of rain gauge stations and the availability of data, 12 rain gauge stations having long-term records in and around the basin are considered for the detailed analysis. The various agencies maintaining these rain gauge stations, and the number of rain gauge stations maintained by each agency are listed below:

S. No. Name of the Agency Numbers 1 Water Resources Department 11 2 Revenue 1 Total 12

The details of the rain gauge stations such as, their location, geographical co-ordinates and the study period are shown in Table A. For the purpose of rainfall analysis, month is taken as a time step. Thiessen polygon map for the raingauge stations have been prepared to study the distribution pattern of rainfall over the basin area is shown in Figure 5.

Figure 5 Thiessen polygon map for the raingauge stations in Agniyar basin Table A – Influencing Raingauge Stations of Agniyar River Basin considered for analysis Data Sl. Longitud Station Name District Taluk Source Latitude availabilit No e y period

1 Adiramapattinam Thanjavur WRO 10020'00" 79023'00" 1971-2017

2 Alangudi Pudukkottai Alangudi WRO 10021'45" 78059'00" 1971-2017

3 Aranthangi Pudukkottai Aranthangi Revenue 10010'00" 79000'00" 1971-2017

4 Pudukkottai Kolathur WRO 10030'50" 78037'30" 1971-2017

5 Kattumavadi Pudukkottai Alangudi WRO 10007'56" 79013'30" 1971-2017

6 Keeranur Pudukkottai Kolathur WRO 10034'20" 78046'50" 1971-2017

7 Kurungulam Thanjavur Thanjavur WRO 10042'00" 79005'30" 1971-2017

8 Pattukkottai Thanjavur Pattukkottai WRO 10026'00" 79019'00" 1971-2017

9 Perungalur Pudukkottai Pudukkottai WRO 10029'40" 78055'45" 1971-2017 10 Pudukkottai Pudukkottai Pudukkottai WRO 10023'15" 78049'30" 1971-2017

11 Thirumayam Pudukkottai Thirumayam WRO 10012'50" 78045'10" 1971-2017

12 Manaparai Trichy Manaparai WRO 10036'15" 78025'50" 1971-2017

Monsoon and non-monsoon periods

Agniyar river basin lies within the tropical monsoon zone. Based on the hydrometeorological features of the basin, year is divided into 1) Monsoon period spanning from June to December and 2) Non-monsoon period spanning from January to May. The monsoon period is further sub-divided into Southwest monsoon period spanning from June to September (4 months) and Northeast monsoon period spanning from October to December (3 months). Similarly, the non-monsoon period is further sub- divided into Winter period spanning from January to February (2 months) and Summer period spanning from March to May (3 months). As the monsoon period brings heavy rainfall, it improves the recharging of groundwater as well as storage of surface water. Hence, the monsoon period is hydrologically significant for water resources analysis. But in the case of non-monsoon period, the rainfall is insignificant. 25%, 50%, 75% & 90% Annual dependable rainfall is given in the table below. Annual Dependable Rainfall – Agniyar Basin (mm) Sl. No. Sub basin 25% 50% 75% 90% 1 Agniyar 373.57 301.68 250.60 198.45 2 Ambuliyar 127.42 110.57 82.98 64.42 3 South Vellar 320.42 281.63 227.56 175.31 Maximum, minimum and average rainfall  Maximum rainfall is 1300.47 mm in Ambuliyar sub basin (2004-05).  Minimum rainfall is 515.45 mm in South velar sub basin (1995-96).  The Annual average rainfall of Agniyar basin varies from 910.40 mm (South Vellar) to 931.59 mm (Agniyar). Aridity Index for Climatic Classification The aridity index for climatic classification for the Agniyar basin is given in the table below

Aridity Index (Ia) For Climatic Classification Total Annual Ave. Ia Name of PET deficit S.No. Precipitation Aridity Classification Stations mm P-PET P mm Index mm 1 Alangudi 843.03 1661 -817.97 -49.25 Semi Arid 2 Aranthangi 1014.67 1661 -646.33 -38.91 Semi Arid 3 Iluppur 859.48 1661 -801.52 -48.26 Semi Arid 4 Kattumavadi 957.11 1661 -703.89 -42.38 Semi Arid 5 Keeranur 868.39 1661 -792.61 -47.72 Semi Arid 6 Pudukotttai 870.96 1661 -790.04 -47.56 Semi Arid 7 Thirumayam 945.73 1661 -715.27 -43.06 Semi Arid 8 Adiramapattinam 1156.94 1661 -504.06 -30.35 Dry Humid 9 Kurungulam 900.98 1661 -760.02 -45.76 Semi Arid 10 Pattukottai 1044.60 1661 -616.40 -37.11 Semi Arid 11 Manaparai 849.27 1661 -811.73 -48.87 Semi Arid Climate The weather station considered for analysis is furnished below:

Name of the weather station Maintained by

PWD (GW) Kurungulam

PWD (GW) Pudukkottai

The climatological values of this river basin are given below. Climatological Parameters S. No Climatological Parameter Kurungulam Pudukkottai 1 Average monthly temperature max. / min. in. 0 Celsius 34.31/25.45 35.32/25.57 2 Average mean temperature in 0 Celsius 29.88 30.45 3 Average relative humidity in % 73.72 70.19 4 Average wind velocity in km/hour 4.63 2.88 5 Average pan evaporation in mm / month 150.50 159.55 6 Average Sunshine hours / day 6.93 6.09

Name of JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Average the FCS Agniyar basin - 115.0 122.0 155.0 159.0 175.0 160.0 158.0 162.0 143.0 117.0 92.0 103.0 138.4 Kurungula m FCS

Surface Water Data

There are three gauging stations in Agniyar river basin maintained by Public Works Department and they are as follows :

Sl.No. Name of Gauging station Name of Sub basin

1 Poovanam anicut Agniyar

2 Adaikkadevan anicut Ambuliyar

3 Manamelkudi anicut South Vellar

Out Flow To Sea

Agniyar

In Agniyar sub basin, readings at the last anicut, Poovanam, for six years indicate average flow of 90 MCM (3.18 TMC).

Ambuliyar

In Ambuliyar sub basin, the flow at the last anicut, Adaikadevan, over five years is 63.88 MCM (2.25 TMC).

South Vellar

In South Vellar sub basin, there was no surplus at Manamelkudi anicut in 5 out of 6 years. In 1993, the flow was 446.39 MCM (15.7 TMC).

The flood surplus of Agniyar basin is given in Table-A. From the surplus flow data, it is evident that, for the period from 1988 to 1992 there has been surplus flow in Agniyar and Ambuliyar rivers but there was no flow in the upper reach of the rivers and there was no surplus flow in South Vellar. The surplus may be due to local run off near the last anicuts and from the tributaries. This is because, most of the tributaries in the Agniyar and Ambuliyar rivers join before their respective last anicuts and South Vellar river does not have any tributary in the tail reach.

Surface Water Potential Surface runoff is the response of a catchment to precipitation reflecting the integrated effects of a wide range of parameters like catchment, climate and precipitation, intensity, duration, size and shape of the catchment, the direction of storm, orientation of the catchment, slope, soil, land use and climate etc.

Monthly Runoff Simulation (MRS) Model assesses the surface water potential for 75% dependable yield for southwest, northeast and non-monsoon periods. The following influential rainfall stations having long-term records are considered for analysis.

Raingauge stations considered for analysis Subbasin No. of Sl. Name of area Raingauge Name of Raingauge station No. subbasins (Sq.Km.) stations 1 Agniyar 2057.86 8 Adiramapattinam, Keeranur, Kurungulam, Pattukaottai, Perungalur

2 Ambuliyar 717.81 6 Alangudi

3 South Vellar 1887.37 10 Aranthangi, Ilupur, Kattumavadi, Pudukkottai, Thirumayam, Manaparai

Total 4663.04 24 Surface Water Potential by MRS Model

75% Dependable Surface Water Potential for Agniyar river basin

75% Dependable Surface Water Name of Potential in MCM Sl.No. Sub basin SW NE NM Annual 1 Agniyar 63.06 151.07 36.48 250.6

2 Ambuliyar 27.52 29.91 25.55 82.98 South 3 Vellar 53.68 125.42 48.46 227.56

Total 144.26 306.4 110.49 561.14 Surface Water Potential of Agniyar Basin is 561 Mcum. The average quantity of water diverted through Grand Anicut Canal to Agniyar basin is 498.5 MCM. The details are as follows:

G.A. canal ayacut in Agniyar basin = 50785 ha or 125488 ac.

Designed duty of G.A.canal = 1043.30 ha/cumec(73 acres/cusecs)

Discharge required = 125488/73 i.e., 1719 c/s or 48.68 cumec

Crop period = 135 days

Base period = 120 days

1 cusec flow per day = 0.0864 mcft Total quantity required = 1719 x 120 x 0.0864 i.e., 17616 Mcft

Hence, diverted water from G.A. canal = 17616 Mcft or 499 MCM

Surface water potential generated within the basin = 561 MCM

Surface water quantity diverted from Cauvery river = 499 MCM

Total Surface water potential = 1060 MCM

The Existing Surface Water Supply Systems

Reservoir Details In this basin, there are no reservoirs across any of the rivers of this basin. The main reason being that none of the rivers have copious flow. The terrain of the country is also flat, and it is difficult to construct any reservoir.

Anicut Details

The anicuts in Agniyar river basin feed a chain of tanks used for irrigation. The irrigation system map of Agniyar river basin area is shown in Plate: AGN-27. The following are the anicuts in Agniyar basin:

Anicut Details In Agniyar Sub Basin

Sl.No. Name of Anicut

1 Sinayakkudi anicut

2 Andakulam anicut

3 Agniyar anicut of Pulavankadu anicut

4 Maniyavayal anicut

5 Madathukkadu anicut

6 Poovanam anicut

7 Kollukkadu pumping scheme

Anicut Details In Ambuliyar Sub Basin

Sl.No. Name of Anicut

1 Pallathividuthy anicut

2 Kothamangalam anicut

3 Nelhadikkadu anicut

4 Senthangudi anicut

5 Chithathikkadu anicut

6 Adaikadevan anicut

Anicut Details In South Vellar Sub Basin

Sl.No. Name of Anicut

1 Kilikudi anicut

2 Pinnakudi anicut

3 Visalur anicut

4 Keemanakanmoi anicut

5 Sundarapatti anicut

6 Senthamangalam anicut

7 Holdsworth anicut

8 Sethukanmoi anicut

9 Kothamangalam anicut

10 Narpavalakudi anicut

11 Panchadthi anicut 12 Veeramangalam anicut

13 Avudayarkovil anicut

14 Karunkadu anicut

15 Manalur anicut

16 Keeranur anicut

17 Manamelkudi anicut

Tanks Ayacut Sl.No. Name of Sub basin No. of Tanks Ha Acre

1 AGNIYAR SUB BASIN

1) Agniyar 959 17304 42756

2) Maharajasamudram 321 6769 16725

2 AMBULIYAR SUB BASIN

1) Upper Ambuliyar 2118 22231 54932

2) Lower Ambuliyar 416 24699 61032

3 SOUTH VELLAR SUB BASIN

1) Upper Vellar 136 2676 6612

2) Lower Vellar 25 2671 6601

TOTAL 3975 76350 188688

4 G.A. CANAL (DIRECT) 44789 110671

Grand Total 3975 121139 299359 In this basin, tank irrigation plays an important role and there are about 3975 irrigation tanks irrigating about 76350 ha. Out of the above, 346 are system tanks and 3629 are non-system tanks. The approximate storage capacity of these tanks is 560 MCM. The abstract of total command area of each sub basin is given below:

The ayacut of Maharajasamudram river is 6769 Ha. The total registered command area in Agniyar sub basin including Maharaja Samudram river basin is 24,073 Ha.

In the Upper Ambuliyar sub basin, there are 2118 system and non-system tanks irrigating an extent of 22,231 Ha. In the Lower Ambuliyar sub basin, there are 416 tanks (system and non-system) with a total registered Command area of 24,699 Ha. The total ayacut in Ambuliyar sub basin is 46930 Ha.

The total registered Command area in the Upper Vellar sub basin is 2676 Ha with 22 system tanks and 114 non-system tanks. The total registered command area in the Lower Vellar sub basin is 2671 Ha excluding the command area of non-system tanks. The total ayacut in South Vellar sub basin is 5347 Ha excluding the command area of non-system tanks.

Grand Anicut Canal

Eventhough there are no reservoirs in this basin the irrigation demand is met out from Cauvery water received through the Grand Anicut Canal. It is supplementing the ayacut under 16 anicuts located in Agniyar, Ambuliyar and their tributaries. The total ayacut benefited by the canal is 50,785 Ha or 1,25,488 acre which is 66.50% of the total command area of Agniyar river basin. There are 74 tanks in supplemented by G.A. Canal irrigating 5997 Ha. In addition to this, the ayacut directly fed by G.A. Canal is 17719 Ha and indirect ayacut fed through 622 tanks in Thanjavur district is 27069 Ha, the total being 44789 Ha. The ayacut is located in Pattukkottai and Peravurani taluks of Thanjavur district and Alangudi, Aranthangi and Avudayarkoil taluks of Pudukkottai district.

The G.A. Canal is supplementing the command area under 16 anicuts located in Agniyar, Pappankanniar, Kalkulam drainage, Kurukkal drainage, Punakuttiyar, Ambuliyar, Villuniar, Marudhankudiyar, Mudianar and Narasinga Cauvery, etc. There are about 388 tanks supplemented by this canal, 236 in Thanjavur district and 152 tanks in Pudukkottai district in addition to direct command area. There are two reaches of G.A. Canal supplementing the command area in Agniyar river basin. Reach 1 from 3 RD/7 to 30 RD/25 (1 RD, i.e., River Distance = 10,000 feet) irrigates the CMP command area in Agniyar river basin to an extent of 16,072 Ha. The direct command area is 14,271.30 Ha and indirect command area through 16 numbers of tanks is 1,800.16 Ha. The second reach from 30 RD/25 to 35 RD/8135 and extension upto South Vellar irrigates a total command area of 34,713.96 Ha. The direct command area is 30,517 Ha and indirect command area through 58 tanks is 4,196.63 Ha. The total direct and indirect command areas are 44,789 Ha and 5,996.79 Ha respectively. Total command area is 50,785.79 Ha.

Inter Basin Transfer Of Water

There is Inter basin transfer of water from Cauvery river basin to Agniyar river basin through Grand Anicut Canal. This Grand anicut diverts the water released from reservoir to meet the irrigation requirements of Agniyar basin. Water from the canal irrigates about 66.50% of the total command area of Agniyar basin.

Groundwater Potential in the Study Area

The total available groundwater potential as on March 2013 is worked out as 893.89 Mcum and is shown in Table below.

Ground Water Potential Calculation as on Mar 2013 Ground water Area in Net water Name of District potential District % available wise

Dindigul 2.87 58016.67 1665.08

Pudukottai 64.43 98591.79 63522.69

Sivagangai 1.06 90618.63 960.56

Thanjavur 23.37 74652.08 17446.19

Tiruchirappalli 8.27 70069.09 5794.71

Total 89389.23057 Ha.m 893.8923057 M.cum

The block wise status for the year 2003 Groundwater Assessments and problem areas in general is also indicated in the Table below.

Classification of the Block based on the level of Ground Water Development

Sl. No. District Block Level 1 Dindigul Nattam Semi Critical

2 Dindigul Sanarpatti Over Exploited

3 Dindigul Vadamadurai Over Exploited

4 Pudukkottai Annavasal Safe

5 Pudukkottai Aranthangi Safe

6 Pudukkottai Arimalam Safe

7 Pudukkottai Avudayarkovil Safe

8 Pudukkottai Gandarvakottai Safe

9 Pudukkottai Safe

10 Pudukkottai Kunnandarkovil Safe

11 Pudukkottai Manamelkudi Safe

12 Pudukkottai Ponnamaravati Safe

13 Pudukkottai Pudukkottai Safe

14 Pudukkottai Tirumayam Safe

15 Pudukkottai Tiruvarangulam Semi Critical

16 Pudukkottai Viralimalai Safe

17 Sivagangai Sakkottai Safe

18 Sivagangai Semmampattipudur Semi Critical

19 Thanjavur Orattanadu Semi Critical

20 Thanjavur Pattukkottai Safe

21 Thanjavur Peravurani Semi Critical

22 Thanjavur Sethubavachatram Safe

23 Thanjavur Thanjavur Safe

24 Thanjavur Tiruvonam Semi Critical

25 Trichy Manaparai Critical 26 Trichy Marungapuri Semi Critical

Aquifer Transmissivity and Hydraulic Conductivity Aquifer parameter in Hard Rocks Sl No Aquifer Parameter Minimum Maximum

1. Well Yield (liters per second.) 17.33 51.50

2. Transmissivity (T) in m2/day 19.22 132.22

3. Permeability (K) in m/day 4.12 16.85

Aquifer parameter in sedimentary formations.

Sl No Aquifer Parameter Minimum Maximum

1. Well Yield (liters per second.) 182.25 826.75

2. Transmissivity (T) in m2/day 152.00 1079.50

3. Permeability (K) in m/day 10.86 30.59

Aquifer parameter in Alluvial formation Sl No Aquifer Parameter Maximum Minimum 1. Well Yield (liters per second.) 650.00 2200.00

2. Transmissivity (T) in m2/day 350.00 2500.00

3. Permeability (K) in m/day 45.00 95.00

Water Level Fluctuations

Long-term hydrographs (1971–2007) of the groundwater levels for all the observation wells have been prepared. In some wells, changes can be seen in the long-term trend. The depletion in water table ranges from 1.0m to 6.6m.

The maximum summer water level and minimum winter water level of individual observation well are taken into account for calculating the fluctuation. The fluctuations differ from well to well and are found to be in the range of 8.6m to 14.2m.

Present and Future Water demand Total water demand is the sum of the sectoral demands such as domestic demand, irrigation demand, livestock demand and industrial demand.

Domestic water demand:

Projected Domestic water demand is calculated and tabulated in the table below.

Year Population Demand

Urban 416000 2001 MLD MCM Rural 1519000

Urban 342518 28.31 2011 34.81 Rural 1676170 67.05

Urban 385731 31.89 2017 38.08 Rural 1811235 72.45

Urban 409341 33.84 2020 39.84 Rural 1882795 75.31

Urban 498984 41.25 2030 46.34 Rural 2142385 85.70 Urban 608259 50.28 2040 53.94 Rural 2437766 97.51 Urban 741464 61.29 2050 Rural 2773872 110.95 62.87

Industrial water demand

Industrial water demand is calculated based on the requirement of Small, Medium and Large scale industries in the basin. The recommendations of the industries department i.e., 2500 cum/day/unit for large and medium scale industries and 2.5 cum/day/unit for small scale industries are adopted for estimating the industrial demand.

WATER DEMAND CALCULATION FOR SMALL, MEDIUM AND LARGE INDUSTRIES BASED ON INDUSTRY CENSUS AS TAKEN FROM IWS

Average 2007 2017 2020 2030 2040 2050 Rate of Water Sl. Type of consumption No. of No. industry as given in industry IWS as per Water No. of Water No. of Water No. of Water No. of Water No. of Water m3/day IWS Demand industry Demand industry Demand industry Demand industry Demand industry Demand Small scale 1 industry 2.5 15023 13.71 32434 29.6 40857 37.28 88207 80.49 190432 173.77 411129 375.16 Medium & large scale 2 industry 2500 51 46.54 110 100.38 139 126.84 299 272.84 646 589.48 1396 1273.85 Total Demand in M.Cum 60.25 129.98 164.12 353.33 763.25 1649 Livestock water demand

The projected livestock water demand is given in Table below

Livestock water demand for Agniyar Basin

Standard Sl. Norms in Demand Demand Demand Demand Demand No. Name lpcd 2017 2020 2030 2040 2050 1 Cattle 110 65.17 66 68.82 71.77 74.84 2 Buffalo 150 3.18 2.78 1.78 1.14 0.73 3 Sheep 20 4.74 4.72 4.68 4.63 4.58 4 Goats 20 13.41 14.34 17.93 22.42 28.04 5 Horses & Ponies 150 0.025 0.025 0.025 0.025 0.025 6 Donkeys 40 0.01 0.01 0.01 0.01 0.01 7 Pigs 40 0.2 0.18 0.11 0.07 0.04 8 Dogs 15 1.402 1.402 1.402 1.402 1.402 9 Rabbits 15 0.018 0.018 0.018 0.018 0.018 10 Poultry 0.25 1.03 1.32 3.01 6.85 15.6

Total 89.185 90.795 97.785 108.335 125.285

WATER BALANCING Water Potential, Demand and Deficit (Both Long & Short Term)

Demand of water in various sectors (MCM) Water availabilty (MCM) Area Quan Contin Surp Any Nam of No. tity Quan gent S lus / other e of the of Surfa Grou of tity plans l. Ye Defic relevan the basi Sub Live ce nd recyc of for N ar Irriga Dome Indust Oth Tota Tota it in t basi n basi stoc water water led water filling o tion stics ries ers l l Mcu inform n (in ns k poten poten water from the Sq.K m ation tial tial from desilt gap m) Sewa ing ge

- 20 1882.9 89.1 2140 1136. 893.8 2029 38.08 129.98 0.00 - 0.00 110.3 17 6 85 .21 00 92 .89 1 Agniyar Pudukkotta - i Dt (753 20 1882.9 90.7 2177 1136. 893.8 2029 39.84 164.12 0.00 - 0.00 147.8 Tanks)- 20 6 95 .72 00 92 .89 50.66,Agni 2 yar Agni 4663 - Thanjavur 1 3 20 1882.9 97.7 2380 1136. 893.8 2029 Dt (432 yar .04 46.34 353.33 0.00 - 0.00 350.5 30 6 85 .42 00 92 .89 Tanks)- 2 27.40 - ,Agniyar 20 1882.9 108. 2754 1136. 893.8 2029 Trichy Dt 0.00 763.25 0.00 - 0.00 724.6 40 6 335 .55 00 92 .89 (13Tanks)- 5 1.21 - 20 1882.9 1649.0 125. 3711 1136. 893.8 2029 53.94 0.00 - 0.00 1681. 50 6 1 285 .20 00 92 .89 30