EVOLUTION OF KARAMANA RIVER BASIN AND ITS IMPLICATIONS ON HYDROGEOLOGY: A GEOMATICS APPROACH USING MORPHOMETRIC ANALYSIS FINAL TECHNICAL REPORT BACK TO LAB PROGRAMME (Project Reference No: 029/WSD-BLS/2013/CSTE) WOMEN SCIENTISTS DIVISION KERALA STATE COUNCIL FOR SCIENCE, TECHNOLOGY AND ENVIRONMENT GOVERNMENT OF KERALA Submitted By SREEJA R. SCHOOL OF ENVIRONMENTAL SCIENCES MAHATMA GANDHI UNIVERSITY KOTTAYAM 2017 AUTHORIZATION The work entitled “EVOLUTION OF KARAMANA RIVER BASIN AND ITS IMPLICATIONS ON HYDROGEOLOGY: A GEOMATICS APPROACH USING MORPHOMETRIC ANALYSIS” by Ms. SREEJA R., wasut carriedunder theo “Back-to-lab”ogramme pr of Women Scientists Division, Kerala State Council for hnologyScience andTec Environment, Govt. of Kerala. The work was carried out at Schoolmental Sciences,of Environ Mahatma Gandhi University, Priyadarsini Hills P.O. Kottayam, 86560.Kerala -The 6 project was sanctioned wide Order No.1016 /2013/ KSCSTE dated 23.10.2013r the duration fo of 3 years with Project Reference No: 029/WSD-BLS/2013/CSTE. The projectas initiatedw on 23.12.2013 and completed on 22.12.2016 with financial a expenditure of Rs. 15,80,579/- (Rupees Fifteen Lakh Eighty ndThousa Five Hundredand Seventy ine).N Group onitoringm workshop (GMW) of Back-to-labojects pr held during 3-4 May, evaluated2017 and graded the project work with 8/10er (LettNo. 124/WSD-BLP/KSCSTE/2017). The suggestions during the GMW isrporated inco in this FinalTechnical Report. i ACKNOWLEDGMENTS I am genuinely obliged to Kerala State Council for Science, Technology and Environment (KSCSTE) for the financial assistance through “Back to Lab program” of the Women Scientists Division (WSD), which enabled me to obtain an independent project I am highly indebted to Mahatma Gandhi University for providing me the necessary facilities and logistical support for carrying out the field work as well as laboratory experiments during the course of the project. I am grateful to Dr. K. R. Lekha, Head, Women Scientists Division, KSCSTE, for the encouragement and support throughout the tenure of the project. I am grateful to Dr. Mahesh Mohan, Assistant Professor, School of Environmental Sciences (SES), Mahatma Gandhi University, for giving consent to become the mentor for the project as well as for his support, constant encouragements, useful discussions and suggestions. I would like to express my sincere thanks to Dr. A. P. Pradeepkumar, Associate professor and Head, Department of Geology, University of Kerala, Thiruvananthapuram for, his invaluable suggestions, advice and encouragement throughout the progress of this project. I place on record my deep sense of gratitude to the support and encouragement given by Dr. C. T. Aravindakumar, Professor and Director, SES , Mahatma Gandhi University. I owe my most sincere gratitude to Dr. E. V. Ramasamy, Associate Professor and former Director, SES, Mahatma Gandhi University, Kottayam for the support and encouragement. I am indebted to Dr. A.P. Thomas, Director, ACESSD, Mahatma Gandhi University, for his support and constant encouragements. My research work was eased through the support rendered by my colleagues especially Mr. Joice K. Joseph, Dr. Sreekanth N.P., Mr. Gopikrishnan V.G., Mr. Abdul Shukoor, Mr. John Richard Thomas, Mr. Kannan V.M, SES, Mahatma Gandhi University, Kottayam and I express my deep sense of thankfulness for their unstinted help in various ways throughout the course of this project. M/s. Salahudheen, Librarian,SES, Mrs. Laila T. Abraham, Mr. Raju and Mr. Murali, Central Library, M.G. University were exceptionally helpful during my literature survey and iii documentation, and I deeply acknowledge their help. I thank all the staff members of SES, M.G. University, for their bountiful support and help. My sincere thanks to Dr. Narasimha Prasad N.B, the Then Executive Director, Centre for Water Resources Development and Management (CWRDM) for his constant encouragement. The support extended by scientific and non-scientific staffs of CWRDM and Research fellows are also acknowledged with gratitude. I wish to express my gratitude to Late Dr. K.M Nair, former Director, CESS, Thiruvananthapuram, who inspired me in scientific research, for his constant encouragement, suggestions, support and parental care. Finally I wish to express my gratitude to my family and relatives for their prayers, affection, encouragement and motivation to pursue this Project. I am deeply indebted to them. Sreeja R. iv TABLE OF CONTENTS 1. AUTHORIZATION i 2. ACKNOWLEDGEMENT iii 3. ABSTRACT vii 4. INTRODUCTION 1 5. REVIEW OF LITERATURE 3 6. OBJECTIVES OF THE STUDY 13 7. MATERIALS AND METHODS 15 FIELD WORK AND SAMPLING 15 LABORATORY ANALYSES 18 COMPUTATION AND COMPILATION 28 8. RESULTS AND DISCUSSION 29 GENERAL PROFILE OF THE STUDY AREA 29 TERRAIN CHARACTERISTICS 41 MORPHOMETRIC ANALYSIS 59 SEDIMENTOLOGY 87 GROUNDWATER CONDITIONS 109 WATER QUALITY 131 9. SUMMARY 169 CONCLUSIONS 173 RECOMMENDATIONS 175 10. OUTCOME OF THE PROJECT 176 11. SCOPE OF FUTURE WORK 177 12. BIBLIOGRAPHY 179 v ABSTRACT The Study area, Karamana River Basin (KRB), is located between North latitudes 8°05’ and 8°45’ and east longitudes 76°45’ and 77°15’and cover an area of 702 km2. The Karamana river is a small mountainous river with main stream length of 68 km, drains through highland, midland and lowland physiographic zones. The average annual rainfall is 2600 mm which ranges from <1400 mm in coastal part to about 4200 mm in the northeastern portions. The study area is composed mainly of crystalline rocks of Archaean age intruded by a number of dolerite dykes, pegmatites and quartz veins. Warkalli beds occurs as detached patches overlying the crystallines, along the coastal tracts. Quaternary deposits are seen in areas close to the river channels and coastal reaches. The major mineral resources are tile and brick clays, crystalline rocks, construction grade sand, graphite and gem minerals like chrysoberyl. There are 30 local bodies (28 grama panchayats, Nedumangad municipality and Thiruvananthapuram Corporation) in the area have about 16 lakhs of population as per 2011 census. Major land use classes are forests, forest plantations, mixed crops, paddy lands and water bodies. Mining and other anthropogenic activities along with natural hazards like landslides, flooding etc., pose severe environmental problems. Major geomorphological units in KRB are lateritic uplands, buried pediments, flood plains, beach and coastal plains. 24.36% of the study area has >20% slope and 75.64% is of <20% slope. Morphometric analysis of the KRB revealed that the drainage network is structurally and tectonically controlled, indicating evidences of uplift associated with folding and faults. Granulometric analysis reveals that pebbles and granules show comparatively higher proportions in the river stretch where the gradients and local turbulence are higher. In addition to the natural processes, manmade obstacles like check dams, bridges etc., also impart marked effect on sedimentological profile of the river. Statistical analysis also reiterates the findings. The mode of transportation in the river channel is mainly rolling and partly by rolling and suspension. Uniform suspension and graded suspension are the chief transportation mechanisms in the reservoirs. Pelagic suspension mode is observed in Peppara reservoir. The net annual groundwater availability is 58.57 MCM, the gross annual groundwater draft is27.91 MCM, the calculated stage of groundwater development is 47.65 % and KRB vii can be categorized for future groundwater development as ‘SAFE’. 30% of the basin shows very high to high groundwater potential. In the settlement areas water is contaminated by the influx of sewage from domestic / urban centres. Precipitation has a direct control over the distribution of chemical signals in the fluvial environments of the study area. Considerable number of the groundwater samples are acidic in nature (27% in Non monsoon and 32% in Monsoon). 93% of the groundwater samples are bacteriologically contaminated. In the Non monsoon season, water in the river mouth regions shows high conductivity, salinity, Na and Cl values indicates sea water ingression due to reduced river flow. Based on these findings, recommendations for the wise use and management of the water resources of the Karamana river basin has been formulated. viii INTRODUCTION Water is vital for the existence of life and so it is known as the elixir of life. The intensified use of the world’s water resources in the last century has been hastened by the subtle and direct consequences of population growth at a scale unprecedented in human history. These developments occur amidst the natural variability in soil types, river drainage networks and climate along the world’s watersheds (Naiman, 1992;Naiman et al., 1995; Walling and Owens, 2003;Arun, 2006). Land and water are two basic components that constitute the foundation of economic growth of a region. Their inter-linkage is very well manifested in a river basin environment. By and large, a river basin is an ideal unit of land surface. A thorough understanding of the various dimensions of river basin environment and its approach to conservation and management of freshwater systems is a daunting challenge to the mankind. Management of rivers includes legal, social, and economic considerations, as well as scientific insights. Considering the importance of river basins in spatial planning, the Government of Kerala has initiated many developmental programmes at various levels, over the years. Reports