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Status of Water Quantity and Quality in Nepal. Ms. Bandana K Pradhan PhD Associate Professor Environment Health Institute of Medicine Community Medicine and Family Health Department E-mail: bandana@healthnet.org.np. Geographical Division of Nepal. (Meter). (65- 1000). (1000-4000).
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Status of Water Quantity and Quality in Nepal Ms. Bandana K Pradhan PhD Associate Professor Environment Health Institute of Medicine Community Medicine and Family Health Department E-mail:bandana@healthnet.org.np
Geographical Division of Nepal (Meter) (65- 1000) (1000-4000) (4000-8848)
Background Surface Water Over 6,000 rivers,make up 54% of the total water coverage • 660 Lakes with >1 ha • Renewable Water 224 billion m3/Y Rainfall Mean annual rainfall 1,700 mm, 75% of which occur during monsoon season Mean Monsoon Rainfall
PRESSURE • QUANTITY • Population • Urbanisation • Industry • Land use change • Poor maintenance • QUALITY • Waste water • Solid waste • Agro-chemicals • STATE • Surface water • Groundwater • Water demand • Water supply • Water coverage • Water quality Pressures Resources Social response Infor-mation Information RESPONSE • Policies • Programmes • Acts & Regulations • Implemented activities • Conventions & treaties • Resource allocation • Institution organisation Social response Analysis Pressure-State-Impact-Response (P-S-I-R) Analytical Framework
Pressure • Rapid growth of population (2.3 % per year) • Rapid urbanisation • Increment of industries • Expansion of agricultural infrastructure: irrigation • Poor maintenance of water reserviours, irrigation canals, water pipelines, etc
Pressure for the Deterioration of Water Quality Domestic Wastewater Man-made Natural Disasters Contamination of Water Bodies Increase in use of Agro-chemicals Solid Waste Land Use Change Industrial Waste
Description 1991 2001 Status - Total Water Availability and Its Use in Nepal Total annual surface water availability (km3/y)* 224 224 Per capita surface water resource (000 m3/y) 12.1 9.6 Total annual withdrawal (km3/y) 12.95 17.1 Per capita withdrawal (000m3/y) 0.71 0.73 Sectoral withdrawal as % of total water withdrawal Domestic 3.97 3.2 Industry 0.34 0.26 Agriculture 95.68 96.54
Status - Kathmandu Valley • Almost All Major Rivers at Source have been tapped for Drinking Water Purpose • Supply of Drinking Water 115 Million Liters/Day • Estimated Daily Demand: 145 Million Liters (in 2000) Meeting 79% of the total Urban Population Demand
Status - Ground Water • Tarai Region • Owns 12 Billion Meters3 (km3) • Annual Potential Extraction 5.8 to 9.6 Billion Meters3 • Current Withdrawal 0.52 Billion Meters3/Year Kathmandu Valley • Total Sustainable Withdrawal 26.3 MLD • Current Extraction 58.6 MLD • Over-Exploitation >60% MLD = million liter per day
Domestic Waste • Non-Existent of Sewerage Network System in all Towns Except Kathmandu Valley Towns • Only 15% of the Total Houses in Kathmandu Valley Towns Accessed to Sewerage Facility • All Domestic Wastewater and Sewers Discharged Directly into the Rivers without Treatment • Recorded an Average of 20,846 Kg BOD/Day for the Bagmati River at the Outlet, Constituted 42% of the Total BOD Load Produced by the Valley’s People • Total Industrial BOD Load Discharged Directly into the River: 3,151 Kg/Day
Industrial pollution Load in Nepal and the Kathmandu Valley Pollution indicators/year Kathmandu Valley Country Waste water volume (million m3) 2.1 8.56 BOD (000 tonnes) 1.15 5.74 TSS ( 000 tonnes) 1.41 9.59 BOD = Biological oxygen demand, TSS = total suspended solid
Increase in Use of Agro-Chemicals • Average Use Of Chemical Fertilizers (NPK)/Hectare Increased from 7.6 Kg in 1975 to 26.6 Kg in 2000 • Use of Fertilisers Estimated to be 420 Kg/Ha in Chitwan District • Altogether 250 Types of Pesticides Used • Average Pesticide Used 0.17 Kg/Hectare in 1986 • Pesticide at the Range of 34–100 ppb in the Samples Detected in the Fish Flesh and Plankton in Three Lakes of the Pokhara Valley, West Nepal
Change in Land Use Pattern • Agricultural Land Increased from 1592,000 to 2968,000 Ha between 1975 and 2000 • Forest Area Declined from 5617,000 to 4269, 000 Ha between 1977 and 2000 • Urban Built-Up Area in Kathmandu Valley Increased From 26% to 46.2% between 1978 and 2000 • Rural Built-Up Areas Increased From 11.2% to 24%
STATE Total Water Quantity Available in Nepal • Total Available Surface 224 Billions m3 • Groundwater Potentials 8.8 Billions m3 • Total Water Demand (Domestic, Industry & Commerce) Estimated To Be 1239.7 Million Litres Per Day For 2000
State The Water Quality Classification of the Bagmati River –Example of Anthropogenic intervention The poorest quality in the valley basin where population density is the highest
Bagmati River in the Kathmandu Valley Near Holy Temple Pashupati Nath
Status - Ground Water Quality of Tarai Region Most of the water samples from tube wells are contaminated with coliform bacteria.
More than 90% people consume water from ground water in the Tarai Region The degree of Arsenic contamination varies in Tarai region but the whole region is at risk zone
Water Use and Waste Water Discharged into near by River by Carpet Industry
Disturbance of river ecology due to sand quarrying activity in the Manohara river, Kathmandu Valley
Water Quality Deterioration due to Relative Volume of Waste Water Discharged into near by River • Domestic waste • Industrial waste
River Water (Polluted ) Collected for Drinking Purpose
The trend of water quality deterioration in the Bagmati River of the Kathmandu valley
Water Quality Status from Different Sources in Kathmandu All the water sources of Kathmandu valley are faecally contaminated in different degree
Impact The so called potable water is not safe, Incidence of diarrhoeal disease does not show any relationship with the increment of access of water supply
Impact Water Quality and Diarrhoeal Disease
Impact (contd.) For the prevention of diarrhoeal disease curative aspect is only given priority
Responses Most of the industries directly discharge their effluent into river. Few industries have treatment plants with primary treatment system as shown in table below
Responses (Contd..) Wastewater Management Efforts in Kathmandu
Response - Acts and Regulation • Solid Waste Act 1987 • Solid Waste Regulations1989 • Industrial Enterprises Act 1992 • Electricity Act 1992 • Water Resources Act 1992 • Water Resources Regulations 1993 • National Policy on Sanitation - 1994, • Environmental Protection Act 1996 • National Water Supply Sector Policy -1998 • The Bagmati Sector Sewerage Construction/Improvement Project
GAPS • A wide gap of data on water quality and quantity for all parts of the country • Inadequacy in regular monitoring of water quality • No lead agency to take on water quality management and coordination among the water organizations at national level • Lack of central data bank on water quality • No water quality standard for all types of industrial effluents • Lack of commitment in implementing the water quality control measures. • Lack of effective awareness programmes at local level about the conservation of water sources.
Recommendation • Urgently require efforts for maintaining drinking water pipeline & controlling open defecation • Provision of potable water to mass general people • Urgently set up a lead agency for coordinating water-related organisations • Initiate water quality monitoring program at national level • Harvesting of rainwater in major urban areas • Effective awareness activities towards conserving water quality &quantity • Recycling of domestic wastewater (Grey water) • Minimise leakage of piped drinking water • More action oriented research activities on water quality and quantity