कᴂद्रीय भूमि जल बो셍ड जल संसाधन, नदी विकास और गंगा संरक्षण विभाग, जल शक्ति मंत्रालय भारत सरकार Central Ground Water Board Department of Water Resources, River Development and Ganga Rejuvenation, Ministry of Jal Shakti Government of India AQUIFER MAPPING AND MANAGEMENT OF GROUND WATER RESOURCES ERNAKULAM DISTRICT, KERALA केरल क्षेत्र, वत셁िनंतपुरम Kerala Region, Thiruvananthapuram AQUIFER MAPPING AND MANAGEMENT PLAN FOR HARD ROCK TERRAINS, ERNAKULAM DISTRICT, KERALA (AAP- 2018-19) GOVERNMENT OF INDIA MINISTRY OF JAL SHAKTI DEPARTMENT OF WATER RESOURCES, RIVER DEVELOPMENT AND GANGA REJUVENATION CENTRAL GROUND WATER BOARD AQUIFER MAPPING AND MANAGEMENT PLAN FOR HARD ROCK TERRAINS OF ERNAKULAM DISTRICT, KERALA (AAP: 2018-19) Roopesh G. Krishnan Scientist – B (JHG) Kerala Region Thiruvananthapuram December,2019 AQUIFER MAPPING AND MANAGEMENT PLAN FOR HARD ROCK TERRAINS, ERNAKULAM DISTRICT, KERALA (AAP- 2018-19) FOREWARD The National Project on Aquifer Mapping (NAQUIM) is an initiative of the Ministry of Jal Shakti, Department of Water Resources, River Development & Ganga Rejuvenation, Government of India, for mapping and managing the entire aquifer systems in the country. The aquifer systems in Kerala are being mapped as part of this Programme and this report pertains to aquifer mapping of the hard rock terrains of Ernakulam district. The target scale of investigation is 1:50,000 and envisages detailed study of the aquifer systems up to 200 m depth, to ascertain their resource, water quality, sustainability, and finally evolve an aquifer management plan. The report titled “Aquifer Mapping and Management plan for hard rock terrains, Ernakulam district, Kerala” gives a complete and detailed scientific account of the various aspects of the hard rock aquifers in the area including its vertical and horizontal dimensions, flow directions, quantum and quality of the resources, of both - the shallow and deeper zones of the hard rock aquifers. Voluminous data were generated consequent to hydrogeological, ground water regime monitoring, ground water quality, exploratory drilling, geophysical studies etc. in the district, and incorporated in the report. The information is further supplemented by various data collected from State departments. It portrays the various ground water issues pertaining to the area along with recommendation for suitable interventions and remedial measures. Thus, it provides a total and holistic solution to the water security problems in Ernakulam district. This document has been prepared under the guidance of Dr. N. Vinayachandran, Scientist D & Nodal Officer, and Smt. Rani. V.R, Scientist C & Team leader. The painstaking efforts of the field hydrogeologist Sh. Roopesh G. Krishnan in carrying out the aquifer mapping and preparation of this report are well appreciated. Dr.V. S Joji, Scientist D deserves appreciation for their meticulous scrutiny of this report before printing. I am also thankful to the Chairman, Members and officers of CGWB, Thiruvananthapuram and 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. This report evolved in the present form through incorporations and modifications as suggested during the presentation of the report before the State Ground Water Coordination Committee (SGWCC), Chaired by the Water Resources Secretary, Kerala State, Sh. B. Ashok, IAS and before the Deputy Collector & District Magistrate, Ernakulam district, Sh. S. Suhas, IAS. Their sincere efforts and encouragements for improvising the content of this report are acknowledged with gratitude. I hope this compilation will be of much 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 ground water resources in Ernakulam district based on sound scientific foot. Thiruvananthapuram, December 2019 Dr.K.R. Sooryanarayana Suptdg. Hydrogeologist Head of Office AQUIFER MAPPING AND MANAGEMENT PLAN FOR HARD ROCK TERRAINS, ERNAKULAM DISTRICT, KERALA (AAP- 2018-19) AQUIFER MAPPING AND MANAGEMENT PLAN FOR HARD ROCK TERRAINS OF ERNAKULAM DISTRICT, KERALA (AAP- 2018-19) Contents 1.0 INTRODUCTION ............................................................................................................................................. 1 1.1 Introduction .................................................................................................................................................. 1 1.2 Objectives ..................................................................................................................................................... 1 1.3 Scope of the study ........................................................................................................................................ 1 1.4 Approach and Methodology ......................................................................................................................... 2 1.5 Basic Geography and Administration .......................................................................................................... 2 1.6. Data availability .......................................................................................................................................... 5 1.7. Data adequacy ............................................................................................................................................. 5 1.8. Data gap analysis & Data generation .......................................................................................................... 5 1.9 Climate and Rainfall ..................................................................................................................................... 6 1.10 Physiography .............................................................................................................................................. 8 1.11 Geomorphology .......................................................................................................................................... 9 1.12 Land Use/ land cover ................................................................................................................................ 11 1 .14 Hydrology and Drainage ......................................................................................................................... 17 1.15 Cropping pattern – Agriculture and Irrigation .......................................................................................... 17 1.16 Recharge practices .................................................................................................................................... 20 1.17 Geology .................................................................................................................................................... 21 1.18 Groundwater and its relation to geological structures .............................................................................. 21 1.19 Previous work and present status of data.................................................................................................. 25 1.20 Industries and Mineral resources .............................................................................................................. 25 2.0 DATA COLLECTION AND GENERATION ................................................................................................... 26 2.1 Data collection and data gap analysis ......................................................................................................... 26 2.2 Hydrogeological data ................................................................................................................................. 28 2.3 Hydrochemical data .................................................................................................................................... 28 2.4 Geophysical data ........................................................................................................................................ 29 2.5 Groundwater exploration data .................................................................................................................... 31 2.6 Hydrological Parameters on ground water recharge .................................................................................. 32 2.7 Determination of storage parameters for shallow aquifers ......................................................................... 33 3.0 DATA INTERPRETATION, INTEGRATION AND AQUIFER MAPPING ..................................................... 34 3.2. Hydrogeological data interpretation .......................................................................................................... 34 3.2.1 Groundwater level ......................................................................................................................... 34 3.2.2 Pumping test of phreatic aquifer .................................................................................................... 41 3.3 Hydro chemical data interpretation ............................................................................................................ 41 3.4 Geophysical studies .................................................................................................................................... 43 3.4.1 Surface geophysical survey ..........................................................................................................