ADB_book_18 April.qxp - Himalayan Document Centre - icimod

forests are also used for infrastructure development,such as roads, schools, buildings, and houses.Deforestation has resulted in increased landslides,soil erosion, floods, and loss of biodiversity.Nepal’s 8 bioclimatic zones and 35 vegetationtypes support a rich biodiversity in terms of fauna andflora. Nepal has more than 100 species of mammals,800 species of birds, 600 species of butterflies,numerous invertebrates, over 5,000 species offlowering plants, and about 200 ferns. Several ofthese have become endangered as a result of variousfactors, including deforestation.About 18% of the land area has beendemarcated as protected and conserved areas.Proper management of the protected areas forbiodiversity conservation, poverty reduction, andlivelihood improvement is a necessity.Soil degradation and loss of productive land areserious environmental problems. With the increasingpopulation and growing need for food, agriculture isbeing expanded to sloping lands and forests. Theheavy monsoon rains make fragile mountain slopesvulnerable to loss and degradation of land and soilthrough landslides, erosion, and river cutting. Asmuch as 5% of all landslides in Nepal are associatedwith newly-constructed roads and trails.Solid waste is a common environmentalproblem in urban areas. The major cities haveexperienced high rates of population growth andunmanaged urban development, which haveresulted in an increasing volume of solid waste. Themain sources of solid waste are urban households.Slightly over 14% of the population live in Nepal’s 58municipalities; they generate more than 80% of allsolid waste. About two thirds of the waste materialsare organic. The impacts of inappropriate solid wastedisposal on rivers and human health are substantial.The disposal of waste into local rivers has adverselyaffected the quality of water and the aesthetic valueof rivers and cities. This problem is particularly acutein Kathmandu Valley.The municipalities are responsible for solidwaste management. However, most municipalitiesdo not have adequate resources or the technicalexpertise to manage solid waste disposal. Solidwaste disposal in landfill sites has become sociallyvery sensitive and people’s participation in it isgenerally weak. Lack of suitable infrastructure, suchas landfill sites, is also a problem in urban areas.Nepal is rich in water resources. Over 6,000rivers and streams drain the country. The rapidincrease in population has increased demands forwater for drinking, sanitation, irrigation, industry,energy, and recreation. Water shortages and waterpollution are serious problems in urban areasbecause of rural-urban migration, population growth,and unplanned urbanization. The problem ofsecuring a safe drinking water supply is very serious,particularly in Kathmandu Valley.There is evidence that water quality isdeteriorating rapidly in urban areas. Urban areasgenerally lack the infrastructure for the collection,treatment, and disposal of sewage. Limited facilitiesbuilt for this purpose are either ineffective ornonfunctional. Drainage is a common problem,particularly in the Terai. As few houses are connectedto the wastewater system, untreated domesticwaste is discharged into rivers. Most households inrural areas do not have latrines; people defecate inopen areas such as riverbanks and public lands.Likewise, most industrial effluents are dischargeddirectly into rivers. All of these practices contribute tosurface and groundwater pollution.Water pollution has become a serious publichealth problem. Biological water pollution, combinedwith inappropriate sanitation and hygienepractices, is responsible for diseases such asdiarrhea, typhoid, skin diseases, and intestinalworms. These are the most common diseases inNepal, and a large number of infants die annuallydue to diarrhea alone. Recently, arsenic contaminationof the groundwater of the Terai has become aconcern.Water pollution has also adversely affectedaquatic ecosystems. Nepal’s rivers have rich aquaticbiodiversity, which is threatened due to growingwater pollution. The rivers of Kathmandu Valley,particularly in the core city areas, have already lostaquatic biodiversity.Air pollution is a serious concern in urban areasdue to dust generated by vehicles, increasing use offossil fuels for transportation, and concentration ofindustries. Air pollution by industrial emission is alocal concern in many areas. Kathmandu Valley isespecially vulnerable to air pollution due to itstopography (a bowl-shaped valley), rapid andhaphazard urbanization, and significant increase ofvehicular transport in narrow streets. In addition, thepoor maintenance of the roads aggravates airpollution by contributing particulate matter to the air.The transport sector is the largest contributor tototal emissions of pollutants in Kathmandu Valley,followed by the household, industrial, and commercialsectors. Gasoline is the largest contributor to thetotal combined emission of all pollutants, whilefuelwood and coal are also major contributors. Withthe improved technology of brick kilns, pollutionfrom this sector is expected to be reduced inKathmandu valley. Indoor air pollution due toburning fuelwood in unventilated rural houses alsocauses serious health hazards.2 Environment Assessment of Nepal : Emerging Issues and Challenges