Dynamic Groundwater Resources of T elangana (2016-17)
DYNAMIC GROUND WATER RESOURCES OF TELANGANA
STATE
“Anyone who can solve the problems of water will be worthy of two Nobel prizes - one for peace and one for science”.
John F. Kennedy
2016-17
August, 2018 Hyderabad
DYNAMIC GROUND WATER RESOURCES OF TELANGANA STATE
2016-17
State Ground Water Department Government of Telangana
Hyderabad
&
Central Ground Water Board Southern Region
Hyderabad
State Ground Water Department, Telangana & Central Ground Water Board, MOWR
DYNAMIC GROUNDWATER RESOURCES OF TELANGANA STATE
(2016-17)
Prepared by
State Ground Water Department, Government of Telangana,
Hyderabad
&
Central Ground Water Board Southern Region
Hyderabad
Under the Overall Guidence of Dr. Pandith Madhunure Director, GWD, Telangana
&
Shri. D.Subba Rao
Regional Director
CGWB, SR, Hyderabad
State Ground Water Department, Telangana & Central Ground Water Board, MOWR
REPORT ON
DYNAMIC GROUNDWATER RESOURCES OF TELANGANA STATE
(2016-17)
CONTRIBUTORS’ FROM STATE GROUND WATER DEPARTMENT
DISTRICT OFFICES
Name
:
Designation (Sri/Smt/Kum)ADILABAD : T. Pulla Rao, A.Hg
BHADRADRI : B. Rajkumar, A.Hg
BHUPALPALLY : B.Sangeetha, A.Hg
HYDERABAD : Dr. G.Vamshi Krishna, A.Hg
JAGITYAL : G.Nagaraju, AH
JANGAON : Ch. Narsimhulu, AGp
JOGULAMBA (GADWAL) : S. Paramesh Goud A.Hg
KAMAREDDY : V.Kumar, TA(Hg)
KARIMNAGAR : P.Sujatha, A.Hg
KHAMMAM : P.Ramakrishna, TA(Hg)
KUMURAM BHEEM : M.Ashok A.Hg
MAHABUBABAD : A. Sabjendar Reddy, A.Gp
MAHABUBNAGAR : R. Manasa, A.Hg
MANCHERIAL : M. Srinivasa Rao, A.Hg
MEDAK : D. Divya Jyothi A.H
MEDCHAL : A.Srivalli, A.Hg
NAGARKURNOOL : T. Mathews, AGp
NALGONDA : V.Ravi, AH.g
NIRMAL : K.Suhasini, A.H
NIZAMABAD : M. Balu, A.Hg
PEDDAPALLY : A.Srikanth, A.Hg
RANGAREDDY : M. Ramesh, A.Hg
SANGAREDDY : Dr. M. Santosh Kumar, A.Hg
SIDDIPET : K. Ravishankar, A.Gp
SIRCILLA : A.Abhilash, TA.H
SURYAPET : K.Rajini, AH.g
VIKARABAD : B. Lavanya, A.Hg
WANAPARTHY : P. Yugendar Reddy, A.Hg
WARANGAL (R) : P.Ravali, TA.H
WARANGAL (U) : S.Shruthi, AH
YADADRI : V. Swathi Sri, A.Hg
Name : Designation
HEAD OFFICE
Sri P.Jyothi Kumar : Deputy Director (Hg) Sri T. Hansaraj : Asst. Director (Hg) Sri. M.Ramesh : Asst. Hydrogeologist Ms. L R Karthika Priya : Asst. Hydrologist Smt. Hafsa Sulthana : Technical Assitant (Hg) Supervision : Sri K.Laxma, Joint Director
Under the Over all Supervision & Guidance Dr. Pandith Madhnure
Director
……
State Ground Water Department, Telangana & Central Ground Water Board, MOWR
DYNAMIC GROUNDWATER RESOURCES OF TELANGANA STATE
(2016-17)
CONTENTS
EXECUTIVE SUMMARY
S.NO. CHAPTER Page.
No.
1.0 INTRODUCTION
1.1 Background for Re-estimation 1
1.2 Constitution of State-Level Committee 1
2.0 HYDROGEOLOGICAL SET UP
2.1 Geographical and Adminstrative setup 3
2.2 Demography 4
2.3 Soils 4
2.4 Climate & Rainfall 4
2.5 Rivers of the State Vis-à-Vis Watersheds 7
2.6 Geological and Hydrogeological Characteristics 8
2.7 Groundwater levels 12
2.8 Ground Water Quality 14
3.0 GROUND WATER RESOURCES ESTIMATION METHODOLOGY- 2015
3.1 Review of Ground Water Resource Estimation Methodologies 20
3.2 Ground water Assesment unit 21
3.3 Ground Water Assesment Sub-Units 21
3.4 Assessment of Annual Replenishable Ground Water Resources 21
3.5 Rainfall Recharge 22
3.6 Percent Deviation 27
3.7 Recharge from Other Resources 27
3.8 Recharge during Monsoon Seasoon 29
3.9 Recharge during Non-Monsoon Seasoon 29
3.10 Total Annual Ground Water Recharge 29
3.11 Annual Extractable Ground Water Recharge (EGR) 29
3.12 Estimation of Ground Water Extraction 30
3.13 Stage of Ground Water Extraction 31
3.14 Validation of Stage of Ground Water Extraction 32
3.15 Categorisation of Assessment Units 33
3.16 Categorisation of Assessment Units Based on Quality 33
State Ground Water Department, Telangana & Central Ground Water Board, MOWR
3.17 Allocation of Ground Water Resource for Utilisation 33 3.18 Net Annual Ground Water Availability for Future Use 34 3.19 Apportioning of Ground Water Assessment from Watershed to Mandal 34 4.0 PROCEDURE FOLLOWED IN PRESENT ASSESSMENT
4.1 Data Sources for Various Data Elements 35
4.2 Various Norms Used in the Computation 35
4.3 Constraints in the Database 37
5.0 COMPUTATION OF GROUND WATER RESOURCES
5.1 Salient Features of the Dynamic Ground Water Resources Estimation 39
5.2 Assessment Method Adopted 39
5.3 Dynamic Ground Water Resources 39
5.4 Salient Features of Ground water ressources 42
5.5 Comparison with the earlier Ground Water Resources Estimates 47 5.6 Districtwise Groundwater Resources in Telangana (2016-17) 48
5.7 Kaleshwaram 51
5.8 Impact of Mission Kakatiya on Groundwater Resources 52 6.0 CONCLUSION
FIGURES
2.1 District map, Telangana State 3
2.2 Soil Map of Telangana State 4
2.3 Agroclimatic Zones, Telangana State 5
2.4 Normal Annual rainfall, Telangana State 7
2.5 River sub-basins and watershed map, Telangana State 8
2.6 Geological map of Telangana State 9
2.7 Ditrict wise status DugWells in Telangana State 11
2.8 District wise Bore Wells in Telangana State 11
2.9 Decadal Hydrograph of Telangana State 12
2.10 Depth to water level pre-monsoon 2016 13
2.11 Depth to water levels post-monsoon 2016 14 2.12 a&b TDS Distribution during Pre and Post Monsoon Season, 2016 18 2.13a&b Flouride Distribution during Pre and Post Monsoon Season, 2016 18 2.14a&b Nitrate Distribution during Pre and Post Monsoon Season, 2016 19
5.1 Ground Water Resources of Telangana 40
5.2 Ground Water Utilization Wise Grouping of Districts 41
State Ground Water Department, Telangana & Central Ground Water Board, MOWR
5.3 Categorization of Watersheds in Telangana (2016-17) 43
5.4 Categorization of Watersheds 43
5.5 Categorization of Mandals in Telangana (2016-17) 44
5.6 Categorization of Mandals, Telangana State 44
5.7 Location of Kaleshwram Project with command area 51
TABLES
2.1 Administrative Set Up 3
2.2 Change in yield pattern & Well Density 10
2.3 Minimum and Maximum values of major parameters during pre-monsoon (May-2016)
16 2.4 Minimum and Maximum values of major parameters during post-monsoon
(Nov-2016)
17 3.1 Validation of Ground water Extraction with comparison to Groundwater level
trend.
32
3.2 Categorisation based on Ground Water Extraction 33
4.1 Data Sources Used in the Ground Water Resource Estimation 36 5.1 Salient Features of Ground Water Resources Estimation 2016-17 (MCM). 40
5.2 District wise Ground Water Resources-2016-17 41
5.3 District wise number of Watersheds in different categories (2016-17) 45 5.4 District wise number of Mandals in Different Categories (2016-17) 46 5.5 Comparison of categorisation of Mandals in Different Assesment Years. 47 5.6 Comparison of categorisation of Watersheds in Different Assesment Years 47 APPENDICES
I G.O issued by the Government of Telangana for constituting the State Level Committee for re-estimation of Dynamic Ground Water Resources as on March 2017
57
II Minutes of the first the State Level Committee for re-estimation of Dynamic Ground Water Resources as on March 2017
60 III Minutes of the Second the State Level Committee for re-estimation of
Dynamic Ground Water Resources on 04 th August 2018
62 IV Minutes of the Central Level Committee for re-estimation of Dynamic Ground
Water Resources on April 2019
65
V Categorizatrion Of Mandals In Telangana State (GEC 2016-17) 68
State Ground Water Department, Telangana & Central Ground Water Board, MOWR
Executive Summary
The National Water Policy enunciates periodic assessment of groundwater resources for quantification, sustainable development and management and as part of this exercise, the State Ground Water Department in coordination with Central Ground Water Board, MOWR, RD & GR Govt of India has taken up the precise estimation of dynamic or replenshible groundwater resources as per the modified GEC guidelines of 2015. The Government of Telangana is regulating groundwater resources with the help of Water, Land and Trees Act No. 10 of 2002 for which State Groundwater Department is furnishing a list of Over Exploited villages for notification and implementation of regulatory measures. Further the planning of all groundwater related projects are dependent upon ground water extraction status.
Telangana State having an area of ~1.12 lakh Km2 and recharge worthy area of ~1.02 lakh Km2 having 21% command and 79% non-command area. State receives a normal annual rainfall of 906 mm of which 80% is contributed by south-west monsoon and 13 % by north east monsoon. The state with 3.5 crore population is predominantly (> 85%) occupied by hard rocks namely, gneisses, granite, basalt and quartzite. Soft rocks namely sandstone, limestone and river alluvium occupy rest of areas.
In present methodology, basic information like village wise cropped area, well census, surface water bodies, various artificial recharge structures, rainfall pattern etc, were collected from line departments considering the base line year of 2016-17 (as on March, 2017). Initially, watershed wise village resources were computed and then apportioned to mandals, based on its area coverage.
Prior to this resource estimations (2016-17), GroundWater Department has carried out estimations during the year 2002, 2005, 2007, 2009, 2011 and 2013. The present estimations are done as per the new guidelines formulated in GEC-2015 and for the first time for urban district like Hyderabad. After bifurcation of State and re- organization of districts, this is the first time that resources are taken up for all 31 districts, covering 584 mandals and 502 watersheds.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR
With advent of drilling techniques in hard rock areas (DTH) well density has increased from 5 wells/Km2 (1985-86) to 18 to 20 wells/Km2 (2016-17) in most of the districts. Comparatively bore wells are more in numbers in Mahabubnagar, Medak, Nalgonda and Nizamabad districts and dug wells in Karimnagar and Warangal districts.
In general, the quality of groundwater in Nalgonda, Warangal and Khammam districts in hard rock formation is generally poor. The quality of groundwater from Gondwana formations is generally good except in some local patches where it is alkaline and hard in nature. Groundwater is often brackish to saline in black cotton soils associated with traps.
As per GEC 2016-17 (as on March, 2017), available extractable groundwater resource is 12367 MCM, gross groundwater extraction (draft) is 8094 MCM and balance available for future irrigation needs is 4317 MCM with stage of groundwater extraction between 23 % (Kumaram Bheem-Asifiabad) to 341 % in Hyderabad with average of 65 %. Out of 584 mandals, 70 mandals fall in Over-Exploited category (>100% stage of groundwater extraction-SGWE), 67 in Critical (90-100 % SGWE), 169 in Semi-critical (70-90% and 278 in Safe category (<70 %). Out of 502 watersheds (groundwater basins), 29 are categorised as Over Exploited (>100%
SGWE), 59 as Critical (90-100%), 165 as Semi critical (70-90%) and 249 as Safe basins (<70%).
The net groundwater availability in the up-coming Kaleshwaram project command area is 75 TMC, groundwater extraction for irrigation and domestic &
Industrial needs 55 TMC and 19 TMC respectively and net available for irrigation needs with 73 % stage of groundwater extraction.
In order to see impact of Mission Kakatiya on groundwater regime, comparison is made with 2013 groundwater resource overall net groundwater availability increased by 14 TMC. It is noticed that overall stage of groundwater extraction decreased by 8% and Over-exploited basins (101%) are now categorised as critical basins (93%)
…..
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 1
1.0 INTRODUCTION
1.1 Background for Re-estimation
The National Water Policy enunciates periodic assessment of groundwater resources for quantification, sustainable development and management. Earlier, as on March, 2013, state wise assessment was done for the entire country. In view of the substantial changes observed in groundwater scenario throughout the country, the Ministry of Water Resources, River Development and Ganga Rejuvenation, Government of India proposed states to re- estimate the groundwater resources with the periodicity of every three years. The Government of Telangana is regulating groundwater resources with the help of Water, Land and Tree Act (Act No. 10 of 2002) and for which the State Ground Water Department is furnishing a list of Over Exploited areas for notification and implementation of regulatory measures. The list of OE villages as per GEC 2013 is notified as per GO Ms.114 PR & RD (RD.1) Department, 25th October of 2018 and as per this order the Government has imposed a ban on construction of new bore wells except for public drinking water purposes until futher orders in 1358 villages. Further, the planning of all groundwater related projects are dependent upon groundwater extraction status.
The state is divided into 2 River basins and 19 sub basins of major and minor rivers.
These 19 sub basins are further sub divided into 502 groundwater watersheds having an average area of ~200 Km2, based on drainage, geomorphology and hydrogeology. Thus, there is a need to assess the groundwater resources more periodically to sustain and manage the resources along with augmentation measures.
1.2 Constitution of State-Level Committee
The Ground Water Department, Government of Telangana in co-ordination with Central Ground Water Board, Southern Region, Hyderabad has taken up re-estimation of groundwater resources for the base year 2016-17, duly following the guidelines and protocols designed for the purpose. Government of Telangana, Vide G.O. Ms.No.762, dated 1st September, 2017 constituted a State Level Groundwater Estimation Committee with 22 members drawn from different Organizations dealing with groundwater and Universities, with the Special Chief Secretary, Irrigation and Command Area Development Department as Chairman and Regional Director, Central Ground Water Board, as the Mmeber Secretary
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 2 (Annexure-I). The responsibility of Assessment of groundwater resource for the state was vested on State Ground Water Department, Government of Telangana.
The first meeting of SLC was held on 21-09-2017 and discussed about the importance of periodic assessment of groundwater resources, which are very much useful to the adminstrators, planners, research scholers and general public. Chairman of the committee instructed GWD and CGWB to submit the draft report latest by 31/03/2017. Subsequently, in view of districts bifercation in the state, the Regional Director, CGWB (Member Convenor) and the Director, GWD requested the Chairman for extension of period to 31st July, 2018 for which permission was granted (Annexure-II)
In this SLCC meeting for re estimation of Groundwater Resources as on March, 2017 held on 4/8/2018 under the chairmanship of Shri Vikas Raj, IAS, Principal Secretary, I&
CAD, Department, Govt of Telangana has approved. The draft re estimation of Groundwater Resources as on March 2017 with the discision incorporate the suggestions made by the members in the final report (Annexure-III).
In its 3rd meeting of Central Level Expert group of overall re assesement of groundwater resources 2017 held under the chairmenship of CGWB on 23rd April, 2019 approved GWRA-2017 (Annexure-IV).
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 3 2.0 HYDROGEOLOGICAL SET UP
2.1 Geographical and Adminstrative setup: Telangana state with a geographical area of 1, 12, 077 Km2 is having ~24 % of forest area (27430 Km2). Administratively state is divided in to 31 districts, 584 mandals and 10,434 villages (Table-1). The state shares its boundaries with Andhra Pradesh on East and South, Chattisgarh in the East, Maharashtra on North and West, and Karnataka on West (Fig.2.1).
Table-2.1 Administrative Set Up
Districts : 31
Revenue Divisions : 68
Mandals : 584
Inhabited Villages : 10,434
Uninhabited Villages : 600
Towns : 158
Fig.2.1: - District map, Telangana State.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 4 2.2 Demography
As per 2011 census, state is having a population of 3.50 crores with a density of 312 person/Km2 of which ~ 61% lives in rural and 39 % in urban area. The male female ratio is 988 females per 1000 males. The state has seen an over all growth of 13.58 % from previous census. The population of Scheduled Caste and Scheduled Tribes is 15.45% and 9.08 % respectively in the state.
2.3 Soils
The soils of Telangana State are mostly red in colour (60%) and in addition, black cotton (Adilabad and Nizamabad), laterite (western part of state) and other soils occur in the state. Black soils occupy districts underlain by Deccan Trap (Basalts) and alluvial soils occur along the major rivers of the state. Soil map of state is given in Fig.2.2.
Fig.2.2: - Soils Map of Telangana State
2.4 Climate & Rainfall
Telangana, in general, experiences tropical climate and is geographically located in a semi-arid area and has predominantly hot and dry climate.
2.4.1 Agroclimatic Zones: Based on climatic parameters Telangana state is devided into 4 Agro-Climatic zones (Fig.2.3).
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 5
Fig.2.3: - Agroclimatic Zones, Telangana State.
a) Northern Telangana Zone: This zone includes Adilabad, Manchirial, Nirmal, Komarambheem Asifabad, Nizamabad, Kammareddy, Karimnagar, Jagityal, Peddaplli and Rajanna Siricilla districts. Annual rainfall ranges from 900 to 1150 mm and is received mostly from south west monsoon. Minimum and maximum temperatures during winter and summer seasonss range between 21°C-25 °C and 32 °C -37 °C, respectively. Red soils are predominant soils in this zone, which include chalks, red sands and deep red loams along with very deep black cotton soils. Rice, maize, soya bean, cotton, red gram, and turmeric are important crops etc, grown in this zone.
b) Central Telangana Zone: This zone includes Medak, Sangareddy, Siddipet, Warangal Urban and Rural, Jayashanker Bhupalpally, Mahabubabad, Khammam, Bhadradri Kothagudem districts and receives an annual rainfall from 800 to 1150 mm. Minimum and maximum temperatures during winter and summer ranges between 21°C- 25 °C and 22 °C-37
°C, respectively. Red soils are predominant which includes chalks, red sands and deep red loams along with very deep black cotton soils. Important crops grown in this zone are cotton, rice, maize, green gram, mango and chilies etc.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 6 c) Southern Telangana Zone: This zone comprises the districts of Rangareddy, Vikarabad, MedchalMalkajgiri, Yadadri, Hyderabad, Mahbubnagar, Gadwal, Wanaparthy, Nagarkurnool, Nalgonda, Suryapet and Jangoan. The annual rainfall ranges from 600 to 780 mm. Minimum and maximum temperatures during winter and summer ranges from 20 °C - 23 °C to 28 °- 37 °C respectively. This zone is predominantly underlain by red soil. Important crops grown in the zone are cotton, rice, red gram, maize, groundnut and green gram etc.
d) High Altitude and Tribal Zone: This zone consists of the areas along Northern and Eastern borders of Adilabad, Bhupalpally and Kothagudem districts and is mostly inhabited by Tribal population. The annual rainfall is around 1400 mm. Important soils in this zone include red sandy loams, red loams with clay base along with very small patches of alluvial soils. Minimum and maximum temperatures during winter and summer ranges between 13 °C-27 °C and 29 °C-34 °C, respectively. Important crops grown in this zone are chillies, rice, cotton and horticultural crops.
2.4.2 Rainfall: Agriculture in Telangana is mostly dependent on rainfall and salient features are given below.
• The normal annual rainfall of the state is 906 mm of which SW monsoon (June- September) contributes 80 % (725 mm), NE monsoon (October-December) contributes 13% (118 mm), winter contributes 1% (9 mm) and summer contributes 6
% (54 mm) of the rainfall. Annual normal rainfall ranges from 402 mm at Ghattu mandal in Mahabubnagar district to 1592 mm at Venkatapuram in Bhoopalapally district (Fig.2.4).
• During the year 2016-17, state received 8 % less rainfall (864 mm) than normal rainfall and S-W monsoon contributed 81% (703 mm), NE monsoon contributed 16
% (134 mm), winter contributed 0 % and summer contributed 3 % (27 mm) of the rainfall.
• None of the districts have experienced drought conditions (<75% of annual normal rainfall) in the state during the year 2017.
• Annual rainfall in 2016-17 ranges from 614 mm (Excess by 1% in Mahabubnagar district) to 1298 mm (Excess by 25 %) in Nizamabad district.
• Annual Potential Evapotranspiration (PET) ranges from 1593 to 1790 mm in the state and monthly PET ranges from 88 mm during December to 234 mm during May.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 7
Fig.2.4: - Normal Annual rainfall, Telangana State.
2.5 Rivers of the State Vis-à-Vis Watersheds
Telangana state is blessed with two major rivers of India viz. Godavari in the North and Krishna in the south. Godavari basin is shared with states of Maharastra, Karnataka Chattisgarh and Andhra Pradesh as co riparian states. Krishna Basin is shared with Maharastra, Karnataka and Andhra Pradesh as co reparian states. These Rivers enter Telangana before flowing down through Andhra Pradesh and before joining into the Bay of Bengal.
The River Godavari with its tributaries Pranahita, Manjeera, Maneru, Indravati, and Kinnerasani drains through the northern parts of the State. The river basin part of flows through Nirmal, Mancherial, Jagityal, Karimnagar, Nizamabad, Kammareddy, Medak, Warangal, Kothagudem, bhoopalapally, Peddapally and Khammam districts. The River Krishna with its tributaries Tungabhadra, Bheema, Musi, Paleru and Munneru flows through the Southern parts of the State and basin is spread over It drains through Mahaboobnagar, Gadwal, Wanaparthy, Nagarkurnool, Ranga Reddy, Vikarabad, Nalgonda and Suryapet districts.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 8 2.5.1 National Codes for Major River Basins of the State
The Godavari river basin is designated as E, and the Krishna river basin is designated as D. The basin area of 2 major rivers in Telangana State has been demarcated into 19 sub basins and are recognized as accounting units for the water. However, these sub basins which range in size from 390 to 15700 km2 are generally not ideal for estimation of dynamic groundwater resources. The ideal recommended size of groundwater estimation unit i.e. the catchments is <300 km2. Hence, for the purpose of groundwater estimation these accounting units were further sub-divided into 502 sub basins known as watersheds having an average area of ~ 200 km2 in consonance with the decision of the Groundwater Resource Estimation Committee. River sub-basins and watershed map of Telangana State is given in Fig.2.5.
Fig.2.5: River sub-basins and watershed map, Telangana State.
2.6 Geological and Hydrogeological Characteristics
Telangana state is characterized by wide range of geological formations from Archaean to Recent age (Fig.2.6). Nearly 85 % of the state is underlain by hard rocks (consolidated formations) belonging to the Peninsular Gneissic Complex, Dharwar and
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 9 Eastern Ghats of Archaean to Middle Proterozoic age, Pakhal Group of rocks belonging to Middle to Upper Proterozoic age and Deccan Traps. The rest of the state is underlain by semi consolidated sedimentory formations comprising Gondwanas, Tertiaries, and Sub-Recent to Recent Unconsolidated Alluvium.
Fig.2.6: Geological map of Telangana State 2.6.1 Hard Rocks
Archaeans, Pre-Cambrians, Pakhals, and Deccan traps are categorized as hard rocks from groundwater point of view. These rocks lack primary porosity and groundwater
occurrence is controlled by extent of weathering and fracturing. These rocks cover nearly
~ 97514 Km2 area (85%) with basaltic formations in the northern and western parts of the state and quartzites in the south eastern parts along the Krishna river. The thickness of weathering generally varies from 10 to 20m and occasionally up to 40 m. These rocks have peculiar geometries in case of gneisses, schist and phyllites based on their hydrulic properties making groundwater behavier differently from place to place, e.g wells constructed only a few metres apart can have huge differences in their yields. It is a question of striking a fracture or not striking it. Ground water yield varies from 0.01 to 10 lps (litres/second) probability of striking a fracture decreases with depth and away from the lineaments/topographic lows. However, in recent times these top fracture zones are de- saturated, in parts of the state drying up the once successful wells or decreasing the chances
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 10 of a successful new well. Results have shown that majority of fractures (90%) occur within 100 m depth in the state.
Aquifer tests have shown that the aquifers have limited porosity due to compactness and secondary porosity is developed due to weathering and fracturing. A 3rd or 4th order basin can have distinct aquifers defined by adjacent catchments. But, the level at which this isolation of aquifer occurs varies and can sometimes occur even within the same trunk of a catchment and sometimes it can cut across a number of catchments. Many of the streamlets are fracture controlled and are classed as lineaments implying structural control by a weak plane in the rock that holds water. The transmissivity (T) in these rocks (Granite and Gneiss) varies from <1 to 630 m2/day with general range of 5-80 m2/day. Specific yield in weathered zone varies from 0.01 to 0.04 and storativity in fracture zone varies from 0.00001 to 0.001.
Ground water yield in deccan traps varies from < 1 lps to > 3 lps and Transmissivity varies from <1 to 10 m2/day with specific yield of 0.01 to 0.02.
Incresed in well density from 5 wells/km2 during 1985-86 to present 18 wells/km2 has resulted in decrease in yields (Table.2.2) and sustainability of wells and as a result area under each well decreased from 4-6 ha to less than 1 ha. In the state of Telangana comparatively more borewells than dug wells are existing in Mahabubnagar, Nizamabad, Medak and Nalgonda and there are more dug wells than bore wells in Karimnagar, Warangal and Adilabad districts (Fig 2.8).
Table-2.2: Change in Yiled pattern & Well Density
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 11 Fig.2.7:District wise Dugwells in Telangana State.
Fig.2.8 :District wise status Borewells in Telangana State.
2.6.2 Semi Consolidated and Unconsolidated Rocks
Semi consolidated formations include Purana and Gondwana group of rocks comprising Sullavai sandstones, Penganga shales, limestones Talchirs, Barakars, Kamthis.
These formations occupy the Godavari valley covering Kothagudem, Bhooplapally, Peddapally, Mancherial, Asifabad and Adilabad districts. These forms important and multi layered aquifers and maximum 12 granular zones have encountered between depth ranges of
0 50 100 150 200 250
Thousands
District wise status of Dug Wells in Telangana State (1986-87 to 2013-14)
1986-87 1993-94 2000-01 2005-06 2013-14
0 20 40 60 80 100 120 140 160 180 200
Thousands
District wise status of BoreWells in Telangana State (1986-87 to 2013-14)
1986-87 1993-94 2000-01 2005-06 2013-14
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 12 25-297 m by CGWB with yield of 1 to 18 lps. Groundwater occurs under unconfined to semi confined and confined conditions and the most promising aquifers among the Gondawana formations in the state. In Maner basin, in Kamthi sandstones auto flow wells are encountered. The transmissivity (T) in these rocks varies from 17 to 700 m2/day and storage co-efficient of 0.2 x 10-4 to 7.9 x 10-4.
The unconsolidated formations are represented by inland river alluvium. The alluvial aquifers have high porosity and permeability. Filter points are most common in this formation. Filter points drilled down to a depth of 5 to 15 meters below ground level (m bgl) yields between 2.5 to 16 lps.
2.7 Groundwater levels:
2.7.1 Decadal Water Levels (2006-2016)
The decadal average hydrograph of the state shows a fall in water level trends @ 12.5 cm/yr. The water level data for a period of about one decade has been considered for analysis which has repicted the decline in trend of 12.5 cm/year (Fig-2.9).
Fig.2.9 Decadal water level trends.
2.7.2 Pre-Monsoon Water Levels (May-2016)
The minimum, maximum and average depth to water levels during premonsoon season in state is from 1.58 , 61.02 mbgl and 16.37 mbgl respectively(Fig-2.10). Shallowest water level is recorded at Piezometer in Veman Pally mandal of Adilabad District in Sandstone formation whereas the deepest water level is recorded in the Piezometer at
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 13 Doultabad of Medak district in granitic formation. During this season deep water levels (>20 mbgl) occurs in western and southern parts of the state and shallow water levels (<5mbgl) during this period were observed in the northern and south-eastern parts of the state. In the rest of the area water levels are in the range of 5-10 & 10-20mbgl.
Fig:2.10:-Depth to water level pre-monsoon 2016.
2.7.2 Post-Monsoon Water Levels (November-2016):
The minimum, maximum and average depth to water levels during post-monsoon season in the state is 0.31 ,45.22 mbgl and 8.34 mbgl respectively (Fig-2.11). Shallowest water level is recorded at Piezometer in Miryalaguda mandal of Nalgonda district in granite formation whereas the deepest water level is recorded in the Piezometer at Shad nagar of Rangareddy district in granitic formation. Deep water levels (>20mbgl) are observed in Medak, Sanga reddy, Siddipet, Ranga reddy, Mahabubnagar, districts. In most of the state water levels are in the range of 5-10 mbgl. Shallow water levels (< 5mbgl) occupy rest of the area more particularly northern & eastern parts of the state.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 14 Fig:2.11 Depth to water levels post-monsoon 2016
2.9 Ground Water Quality
The chemical quality of groundwater exhibits considerable variations from place to place and geological environment, climate and drainage have a profound influence on its quality. In recent past contamination by number of sources including the geogenic and anthropogenioc activity like excess utilization of fertilizers, industrial effluents discharges are causing a lot of harm and damage to groundwater system. The groundwater in Archaean crystalline rocks is in general neutral to alkaline in nature. Groundwater from these rocks is geogenically contaminated in some parts of state with fluoride, more particularly Nalgonda district, Ranga reddy, Siddipet, Yadadri, Warangal(U), western part of Nagar Kurnool, Mahaboobnagar, Jangaon and Kothagudem Bhadradri. The quality of groundwater in Nalgonda, Warangal and Khammam districts in this formation is generally poor on total dissolved solids (TDS) at some of these places exceeds 4800 mg/l. The quality of groundwater from Gondwana formations is generally good except in some local patches where it is alkaline and hard in nature. Groundwater is often brackish to saline in black cotton soils associated with traps.
An attempt has been made to provide an insight into the quality aspect of groundwater along with the present groundwater resource estimation. Since, this is an attempt to make such an effort to link up quality with quantity in groundwater resource estimation, it was
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 15 decided to collect as much data as available at village level wherever possible. 1848 number samples commom & developed aquifers on collected during pre and post-monsoon season of 2016 from existing network of Peizometers.
The groundwater quality is studied primarily for drinking and irrigation suitability and the data summerised data for pre monsoon & post monsoon season of 2016 is gives in Table- 2.3 &2.4. The chemical parameters like electrical conductivity (EC), TDS, pH, chloride (Cl), fluoride (F) and nitrate (NO3) studied in more detail. The other important parameters are CO3, HCO3, Na, K, Ca, Mg, SO4, TH etc. are also studied. Among all these parameters EC and pH are measeured in field level and others at the chemical laboratory at Hyderabad (Level II+) and Karimnagar (Level II).
2.8.1 Pre-Monsoon Season (2016): This pre-monsoon season pH ranges from 6.83 (Mahabubabad) to 9.93 (Rangareddy), EC from 303 (Komurmbheem Asifabad) to 6960 µ/cm (Rajanna Sircilla), TDS from 211 (Jayashankar Bhupalapally) to 4864 mg/l (Yadadri Bhuvanagiri) (Fig. 2.12.a). Fluoride concentration varies from 0.02 (Mancheryal) to 6.01mg/l (Warangal Urban) (Fig. 2.13.a), and NO3 from 0.08 (Jagityal) to 581 mg/l (Nalgonda) (Fig.
2.14.a).
2.8.2 Post-Monsoon Season (2016): During post-monsoon season pH ranges from 5.96 (Bhadradri Kothagudem) to 9.18 (Komurambheem Asifabad), EC from 120 (Bhadrardi Kothagudem) to 14720 µ/cm (Jogulamba Gadwal), TDS from 51 (Rangareddy) to 9421 mg/l (Jogulamba Gadwal) (Fig. 2.12.b), fluoride ranges from 0.01 (Bhadradri Kothagudem) to 5.21 mg/l (Rajanna Sircilla) (Fig. 2.13.b) and NO3 from 1 (Rangareddy) to 1192 mg/l (Nalgonda) (Fig. 2.14.b). The quality of groundwater in general is suitable for both drinking as well as for irrigation purposes except in localized areas where either only salinity or fluoride or nitrate or both concentrations are more. Higher concentration of NO3 is reported in isolated patches from almost all districts, however, very high concentration amounts are reported from parts of canal command areas and urban area of state.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 16
Table-2.3 Minimum and Maximum values of major parameters during pre-monsoon (May-2016).
PREMONSOON 2016 (Range)
DISTRICT pH EC
(µS /cm) TDS (mg/L) CI ( mg/L)
F
(mg/L) NO3 (mg/l)
ADILABAD 8.07-8.88 420-1720 269-1101 40-340 0.10-1.79 2-207
BHADRADRI 7.00-8.45 521-3310 333-1101 40-650 0.22-3.70 4-525
BHUPALPALLY 7.63-8.89 330-3010 211-1926 30-740 0.08-1.58 0.40-199
HYDERABAD 8.18-8.79 690-1960 442-1254 100-380 0.36-1.80 06-53.0
JAGITYAL 7.77-8.51 597-2556 382-1636 40-780 0.15-4.47 0.08-176
JANGAON 7.69-9.01 591-3110 378-1990 30-820 0.13-2.52 2-223
JOGULAMBA(GADWAL) 7.35-8.89 969-5330 620-3411 140-1020 0.10-1.60 14-250
KAMAREDDY 7.60-8.85 429-3060 275-1958 20-670 0.35-4.70 6-199
KARIMNAGAR 7.65-8.60 521-2017 333-1291 40-430 0.30-3.94 2-161
KHAMMAM 7.48-8.21 646-2370 413-1517 50-450 0.25-1.30 1-312
KUMURAM BHEEM 7.97-8.77 303-1845 194-1181 30-330 0.04-1.74 3-248
MAHABUBABAD 6.83-8.80 370-6370 237-4077 40-1770 0.33-1.96 1-430
MAHABUBNAGAR 7.23-8.73 427-3120 273-1997 20-650 0.45-2.00 2-187
MANCHERIAL 7.98-8.63 478-1920 306-1229 50-770 0.02-2.52 0.40-50
MEDAK 732-8.83 512-2670 328-1709 20-580 0.29-3.10 8-188
MEDCHAL 6.71-8.82 354-2120 227-1357 20-390 0.27-2.30 3-184
NAGARKURNOOL 7.52-8.54 609-3600 390-2307 30-650 0.39-2.60 40-509
NALGONDA 7.01-8.98 455-4400 291-2816 20-1310 0.24-5.50 3-581
NIRMAL 7.98-8.48 444-2580 284-1651 50-680 0.27-1.40 01- 51.0
NIZAMABAD 7.57-8.90 428-1830 274-1076 30-440 0.47-2.00 2- 177
PEDDAPALLY 7.62-8.55 612-1706 392-1092 40-200 0.15-1.70 0.04-218
RANGAREDDY 6.91-9.93 500-4120 320-2637 10-930 0.28-5.80 0.20-421
SANGAREDDY 7.98-8.82 395-1770 253-1133 20-350 0.59-2.80 2-120
SIDDIPET 7.45-8.94 350-6950 224-4448 20-1780 0.17-3.20 6-642
SIRCILLA 7.60-8.44 531-6960 340-4454 70-1790 0.41-3.88 3-271
SURYAPET 7.52-8.98 332-3090 212-1978 10-530 0.23-2.30 1-388
VIKARABAD 6.70-7.72 354-1640 227-1050 10-200 0.27-2.10 15-207
WANAPARTHY 7.75-8.89 609-3480 390-2227 70-860 0.39-2.00 19-78
WARANGAL (R) 7.09-8.81 480-4780 307-3059 40-1100 0.35-2.52 4-372
WARANGAL (U) 7.68-8.90 480-2730 307-1747 40-870 0.32-6.01 2-221
YADADRI 7.20-8.97 415-7600 266-4864 20-2190 0.39-3.60 1-465
Table-2.4 Minimum and Maximum values of major parameters during post-monsoon (Nov-2016).
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 17
POSTMONSOON 2016(Range)
DISTRICTS pH TDS (mg/L) EC
(µS /cm)
CI ( mg/L)
F
(mg/L) NO3 (mg/l)
ADILABAD 7.68-8.69 275-1045 430-1633 20-380 0.10-1.91 3-47.0
BHADRADRI 5.96-7.97 77-1933 120-3030 10-360 0.01-4.37 4-437
BHUPALPALLY 8.19-8.78 171-1027 267-1605 20-220 0.08-1.52 1-235
HYDERABAD 7.15-8.65 372-1002 581-1566 100-190 0.52-1.42 2-133
JAGITYAL 7.7-851 255-1453 398-2270 20-490 0.24-2.03 4-165
JANGAON 7.33-8.42 288-1421 450-2220 10-580 0.24-2.90 19176
JOGULAMBA(GADWAL) 7.61-9.16 592-9421 925-14720 50-2500 0.47-4.21 4-279
KAMAREDDY 7.05-8.30 375-1632 586-2550 30-350 0.38-3.62 13-129
KARIMNAGAR 7.70-9.05 256-1021 400-1596 30-270 0.32-3.06 2-131
KHAMMAM 7.3-8.6 403-1997 629-3120 30-580 0.50-2.26 1-443
KUMURAM BHEEM 7.36-9.18 224-1562 350-2440 10-290 0.17-598 4-152
MAHABUBABAD 7.73-8.88 244-1590 382-2480 20-380 0.14-2.22 1-169
MAHABUBNAGAR 7.62-9.04 350-3891 547-6080 30-1900 0.25-2.04 3-297
MANCHERIAL 7.52-8.81 209-1850 327-2890 30-480 0.12-2.78 5-237
MEDAK 7.26-8.76 133-1856 208-2900 10-360 0.37-1.98 2-270
MEDCHAL 6.71-8.82 227-1408 354-2200 20-510 0.27-1.91 2-166
NAGARKURNOOL 7.01-8.01 447-2227 699-3480 50-910 0.22-2.05 7-360
NALGONDA 7.24-8.93 350-4582 547-7160 10-1290 0.10-4.67 2-1192
NIRMAL 8.09-8.35 266-1133 416-1770 20-350 0.16-4.64 4-131
NIZAMABAD 6.78-7.74 479-1135 749-2290 10-420 0.48-1.94 6 - 487
PEDDAPALLY 8.23-8.69 170-1645 265-2570 10-500 0.23-2.83 1-79.0
RANGAREDDY 6.53-8.78 51-2080 80-3250 10-540 0.04-4.76 1-289
SANGAREDDY 6.89-8.68 218-1459 340-2280 20-530 0.23-1.48 31-345
SIDDIPET 7.35-8.87 134-3834 210-5990 10-1410 0.22-3.34 6-1090
SIRCILLA 7.52-8.69 100-1536 156-2400 10-350 0.11-5.21 1-252
SURYAPET 6.82-8.89 234-2336 367-3650 10-860 0.32-2.21 3-310
VIKARABAD 7.07-7.98 173-1408 270-2200 10-320 0.33-1.93 2-423
WANAPARTHY 7.23-8.82 508-2982 793-4660 20-780 0.39-1.44 10-498
WARANGAL (R) 8.07-8.71 220-2656 344-4150 20-1090 0.43-3.30 1-247
WARANGAL (U) 7.36-8.71 374-2310 585-3610 80-670 0.26-5.07 13-383
YADADRI 7.18-8.73 194-3629 303-5670 10-1430 0.35-3.82 3-669
Remarks: Excess Fluoride is present in Nalgonda, Kamareddy, Jogulamba Gadwal, SangaReddy, Karimnagar, Jagityal, RajannaSricilla, Warangal urban and Mancherial districts districts. Excess NO3 is reported from parts of almost all districts as patches, however, very high amounts are reported from parts of Mahabubnagar, Nalgonda, Warangal and Adilabad.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 18 Fig-12 a&b: -TDS Distribution during Pre and Post Monsoon Season, 2016.
Fig-2.13 a&b:-Fluoride Distribution during Pre and Post Monsoon, 2016.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 19 Fig 2.14 a&b: -Nitrate Distribution during Pre and Post Monsoon season, 2016.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 20 3.0 GROUND WATER RESOURCES ESTIMATION METHODOLOGY- 2015 3.1 Review of Ground Water Resource Assessment Methodologies
Attempts have been made from time to time by various Working Groups/Committees/Task Force, constituted by Government of India to estimate the ground water resources of the country based on status of available data and in response to developmental needs. But, due to paucity of scientific data and incomplete understanding of the parameters involved in recharge and discharge processes, all these early estimations were tentative and at best approximation. In 1972, guidelines for an approximate evaluation of ground water potential was circulated by the Ministry of Agriculture, Government of India to all the State Governments and financial institutions. The guidelines recommended norms for ground water recharge from rainfall and from other sources.
The first attempt to estimate the ground water resources on a scientific basis was made in 1979. A High-level Committee, known as Ground Water Over Exploitation Committee was constituted by the then Agriculture Refinance and Development Corporation (ARDC). The committee was headed by the Chairman, CGWB and representatives from the State ground water organizations and financial institutions were included as its members.
This Committee recommended definite norms for ground water resources computations.
In the year 1982, Government of India constituted “Ground Water Estimation Committee” (GEC) with the members drawn from various organizations engaged in hydrogeological studies and ground water development. In 1984 this Committee, after reviewing the data collected by Central and State agencies, Research Organisations, universities, etc. recommended the methods for ground water recharge estimation. This is popularly known as GEC 1984 and This was the first proof which dealt with the subject exhaustively and assessed the resources on a fool proof methodology. This methodology was in practice for next 12 years.
In the year 1996, Government of India again constituted “Ground Water Estimation Committee” (GEC) with the members taken from various organizations engaged in hydrogeological studies and ground water development. In 1997 this Committee, after reviewing the data collected by central and state agencies, research organisations, universities, etc. recommended the methods for ground water recharge estimation. This methodology is popularly known as GEC 1997.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 21 The GEC - 1997 is further revised with technical inputs from Government, Non- Government bodies, Scientific organizations and Universities with the modifications suggested by GEC -1997, GEC - 2004, and the R&D Advisory committee on the Ground Water Resources Estimation from time to time and following the broad guidelines issued by the Central Ground Water Board, Ministry of Water Resources, River Devlopment and Ganga Rejuvenation, Govt. of India.
The present ground water resources estimation of the State of Telangana has been carried out based on the recommendations of GEC-2015. As major part of the state is underlain by hard rocks, watershed was taken as the assessment unit for the entire state. After excluding the hilly areas where slope is > 20%, the ground water resources estimation was carried out for rest of the area. The resources were estimated separately for command and non- command and poor-quality areas and the ground water resources estimation was carried out separately for both sub units. The recommendations of this Committee are summarised in this chapter.
3.2 Ground Water Assessment Unit
A watershed with well-defined hydrological boundaries is an appropriate unit for ground water resource estimation if the principal aquifer is other than alluvium. Ground water resources were worked out on watershed as a unit, and was apportioned and presented on administrative units (block/taluka/mandal/ firka). This would facilitate local administration in planning of ground water management programmes.
3.3 Ground Water Assessment Sub-Units
As recommended, ground water recharge was estimated for the entire assessment unit.
Out of the total geographical area of the unit, hilly areas wherever slope is greater than 20%, are identified and subtracted as these areas have more runoff than infiltration. The hilly areas wherever slope is more than 20% was demarcated using DEM data and geomorphological maps. As per the the methodology, after the assessment is done, a quality tag was added to the assessment unit for parameters like salinity, fluoride and arsenic. Assessment was carried out for command and non-command areas separately.
3.4 Assessment of Annual Replenishable Ground Water Resources
The methodology for ground water resources estimation is based on the principle of water balance as given below –
Inflow – Outflow = Change in Storage (of an aquifer) 1
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 22 Equation 1 can be further elaborated as -
∆S= RRF+RSTR+RC+RSWI+RGWI+RTP+RWCS±VF ± LF -GE-T-E-B 2 Where,
∆S – Change is storage RRF – Rainfall recharge
RSTR- Recharge from stream channels Rc – Recharge from canals
RSWI – Recharge from surface water irrigation RGWI- Recharge from ground water irrigation RTP- Recharge from Tanks& Ponds
RWCS – Recharge from water conservation structures VF – Vertical flow across the aquifer system
LF- Lateral flow along the aquifer system (throughflow) GE-Ground Water Extraction
T- Transpiration E- Evaporation B-Base flow
Eventhough, it is preferred that all the components of water balance equation be estimated in an assessment unit, the present status of database available with Government and non-government agencies is not adequate to carry out detailed ground water budgeting in most of the assessment units. Therefore, at present the water budget was restricted to the major components only taking into consideration certain reasonable assumptions. The estimation is to be carried out using lumped parameter estimation approach keeping in mind that data from many more sources if available may be used for refining the assessment.
3.5 Rainfall Recharge
As recommended that ground water recharge was estimated on ground water level fluctuation and specific yield approach since this method takes into account the response of ground water levels to ground water input and output components. This, however, requires adequately spaced representative water level measurement for a sufficiently long period.
Water level data was considered for a minimum period of 5 years (preferably 10years), along with corresponding rainfall data. The rainfall recharge during non-monsoon season was estimated using rainfall infiltration factor method.
State Ground Water Department, Telangana & Central Ground Water Board, MOWR Page 23 3.5.1 Ground water level fluctuation method
The ground water level fluctuation method is used for assessment of rainfall recharge in the monsoon season. The ground water balance equation in non-command areas is given by
∆S= RRF+RSTR+RSWI+RGWI+RTP+RWCS±VF ± LF -GE-T-E-B 3 Where,
∆S – Change is storage RRF – Rainfall recharge
RSTR- Recharge from stream channels
RSWI – Recharge from surface water irrigation (Lift Irrigation) RGWI- Recharge from ground water irrigation
RTP- Recharge from tank& ponds
RWCS – Recharge from water conservation structures VF – Vertical flow across the aquifer system
LF- Lateral flow along the aquifer system (throughflow) GE- Ground water Extraction
T- Transpiration E- Evaporation B- Base flow
Whereas the water balance equation in command area will have another term Recharge due to canals (RC) and the equation will be as follows:
∆S= RRF+RSTR+RC+RSWI+RGWI+RT+RWCS±VF ± LF -GE-T-E-B 4 The change in storage can be estimated using the following equation:
∆S= ∆h*A*SY 5
Where ∆S – Change is storage
∆h - rise in water level in the monsoon season A - Area for computation of recharge
Sy - Specific Yield
Substituting the expression in equation 5 for storage increase ∆S in terms of water level fluctuation and specific yield, the equations 3 &4 becomes,
RRF= h x Sy x A -RSTR -RSWI- RGWI- RTP - RWCS± VF ± LF + GE + T + E + B 6 RRF= h x Sy x A - RC - RSTR -RSWI- RGWI-RTP -RWCS±VF ±LF +GE +T +E + B 7
The recharge calculated from equation 6 in case of non-command sub units and equation 7 in case of command sub units and poor ground water quality sub units gives the rainfall recharge for the particular monsoon season. However, it may be noted that in case
