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    Performance of Wastewater Treatment Plants (BASP andSWTP) In Kathmandu Valley: Case Study of Bagmati AreaSewerage Treatment Plant (BASP) and Sunga WastewaterTreatment Plant (SWTP).

    Kabindra Pudasaini

    MSc Thesis WM.08.27April 2008

    UNESCO-IHEInstitute for Water Education

  • UNESCO-IHEInstitute for Water Education

    Performance of Wastewater Treatment Plants (BASP andSWTP) In Kathmandu Valley: Case Study of Bagmati AreaSewerage Treatment Plant (BASP) and Sunga WastewaterTreatment Plant (SWTP).

    Master of Science ThesisBy

    Kabindra Pudasaini

    MentorDr.Klaas Schwartz (UNESCO-IHE)

    Examination committeeProf. Meine Pieter van Dijk (Chairman) (UNESCO-IHE)

    Mr.Peter Ryan (IRC)Dr. Klaas Schwartz (UNESCO-IHE)

    This research is done for the partial fulfilment of requirements for the Master of Science degree at theUNESCO-IHE Institute for Water Education, Delft, the Netherlands

    DelftApril 2008

    Lac- "2V'- 0

  • The findings, interpretations and conclusions expressed in this study do neither necessarilyreflect the views of the UNESCO-IHE Institute for Water Education, nor of the individualmembers of the MSc committee, nor of their respective employers.

  • Abstract

    Kathmandu valley faces numerous environmental problems due to the rapid urbangrowth and unplanned settlement. The rapid and haphazard urban growth isexerting immense pressure on urban environment and municipal mangers often donot have sufficient expertise and resources to deal with the rapid growth. In thiscontext, urban sanitation has become a major challenge for municipalities andsmall towns in Nepal

    The majority of urban areas do not have access to sewerage networks except forthree cities in the Kathmandu Valley. Most of the domestic as well as industrialwastewater generated from these cities is discharged into the local rivers withoutany treatment. Out of the total urban population only 76 % have access to toiletswhile the remaining use opens spaces, riverbanks for defecation. More than 60%of urban wastewater is directly deposited in tributaries in the Bagmati River in theKathmandu Valley. This is one of the most pressing problems of Kathmandu.Existing wastewater treatment systems are becoming antiquated while urbangrowth has rapidly increased the number of people requiring new services. Inmost cases, sewer and sewage treatment systems are lacking or not functioning, oroperating at far below the capacity and standards required for municipalities. Inaddition, many towns in the country are unable to operate schemes in a financiallyviable manner while providing the quality of service necessary to satisfycustomers' expectations.

    The main objective of this study is to evaluate the performance in terms ofoperation and maintenance, financial viability, environmental quality andregulations from the concerned authorities of the two separate wastewatertreatment plants, Bagmati Area Sewerage Treatment Plant (BASP) and SungaWastewater Treatment Plant (SWTP) in the Kathmandu valley.

    The performance of the two wastewater treatment plants is studied, focusing onfour main indicators. In-order to find the present scenario and problems about thewastewater treatment systems, the study was carried out by literature reviewed,interviews with 24 key informants, 54 numbers of households and 19 of theindustries in BASP area, and 5 of households in Sunga community.

    Two different systems has been observed, one is the conventional centralizewastewater treatment plant and the other a community based wastewater treatmentplant (reed bed). The performance of the cluster or community based wastewatertreatment plants seems rather better although the coverage area is minimal. Thestudy recommended some preventive measure of the problems andrecommendation for the further study about the problem of wastewater treatmentplants in Kathmandu valley.

    Keywords:Sewerage Treatment System, Operation and Maintenance Financial Viable,Quality, Conventional wastewater treatment plant, Community based wastewatertreatment plant.

  • Acknowledgements

    First and foremost I would like to thank Nuffic for providing me the fellowship for my MScprogramme.

    I would like to express my gratitude to my professor Meine Pieter van Dijk and mentor DrKlaas Schwartz who regularly guided me for completion of this thesis.

    Completing my research would not have been possible with out the support of staff member'sof UNESCO-IHE. Although there are too many to name individually, I would like toexplicitly mention Inika Melis, Claudia Brakel, Wendy Sturrock, programme coordinatorSusan Grass and all of the water management groups who provided me assistance to completethis thesis.

    On my sandwich programme, I have to thank first of all the staff members of Bagmati areawastewater treatment plant who provided me supportive data and permitted me to visit thesites at any time without any restriction. I would like express my appreciation to members ofSunga Commitee and Staff Members of ENPHO. I am very grateful to Dr Roshan R.Shresthaand Bhusan Tuladhar, who both provided me more information about constructed wetlands.

    I would like to give special thanks to Ram Deep Shah, Ganesh Shah, Bhima Nepal, KabitaBhattartai and Dr Chet Bahadur Pariyar who provided me much information about wastewatertreatment plants in the Kathmandu valley.

    My special thanks to Nepal Water Supply Corporation, all key informants, household owners,community members and industry owners, without their support my thesis would not havebeen completed.

    I would like to extend my sincere thanks to Aimee Swartz, Krishna Prasad Poudel and Dr.Rajendra Adhikari for supporting me to write the thesis.

    Finally, and certainly not least, I would like to express my overwhelming gratitude to all ofmy colleagues and my family members for their affection and encouragement during my stayhere in the Netherlands.


  • Table of Content

    Abstract i

    Acknowledgements ii

    1 Introduction 1

    1.1 Background. /

    1.2 Wastewater treatment status in Kathmandu valley 1

    1.3 General Historic Background of Sewerage Systems and WWTPs 3

    1.4 Problem Statement 3

    1.5 Rational of the study 4

    1.6 Overall Objective 41.6.1 Specific Objectives 51.6.2 Major Research Questions 51.6.3 Sub Research Questions 51.6.4 Scope and Limitation 51.6.5 Organization of Thesis 61.6.6 Conceptual Framework of the Study 7

    2 Rules, Legislation and Stakeholder Participation 8

    2.1 Environmental Protection Act (EPA), 1997 8

    2.2 The Building Code 8

    2.3 Local Self Governance Act, 1999 9

    2.4 National Sanitation Policies (2002) 9

    2.5 Nepal Water Resource Strategy 10

    2.6 Nepal Water Plan 11

    2.7 Potential Stakeholders in Sanitation 122.1.\ Introduction 122.7.2 Ministry of Local Development (MLD) and Local Bodies 122.7.3 The Ministry of Physical Planning and Works (MPPW) 122.7.4 Nepal Water Supply Corporation (NWSC) 132.7.5 Department of Water Supply and Sewerage (DWSS) 132.7.6 Melamchi Water Supply Project (MWSP) 132.7.7 The Ministry of Population and Environment (MOPE) 132.7.8 The Non Government Organizations (NGOs) and Environmental Groups 142.7.9 Donors and funding agencies 14

    3 Literature Review 15

    3.1 Wastewater and its treatment 153.1.1 System of Wastewater Treatment 15

    3.2 Wastewater Management in Urban Areas 183.2.1 Domestic wastewater 18


  • 3.2.2 Industrial Wastewater 18

    3.3 Wastewater treatment plant selection in Kathmandu Valley 193.3.1 Sanitation in Urban poor area 21

    3.4 Constructed Wetlands with Hybrid System 233.4.1 Wetlands Wastewater Treatment System 243.4.2 Pollutant Removal Mechanism in Constructed Wetlands 24

    4 Methodology 25

    4.1 Study Area 25

    4.2 Research Framework 27

    4.3 Emperical Material for answer the research questions 294.3.1 Literature and documents review 294.3.2 Consultation with Staffs Member of BASP and SWTP 304.3.3 Consultation with institutions working in the water and sanitation sector 304.3.4 Household survey in Wastewater treatment plant dominant areas 30

    5 Case Study 32

    5.1 Bagmati A rea Sewerage Construction /Rehabilitation Project (BASP) 325.1.1 Introduction 325.1.2 Objective of the BASP 335.1.3 Major Components of the STP 345.1.4 Primary Operation Unit 345.1.5 Biological Operation Unit 355.1.6 Cost of Oxidation Ditch 355.1.7 Secondary Operation Unit 355.1.8 Sludge Treatment Unit 365.1.9 Sewer Tunnel from Tamraganga to Tilganga 365.1.10 Construction of Road, Green Belt and River Training Works 385.1.11 Public Awareness Programme 385.1.12 Economy and Benefits of the project 385.1.13 Operation and Maintenance of the Plant/Project 385.1.14 Organization Structure of BASP 38

    5.2 Sunga Wastewater Treatment Plant, Thimi Municipality (SWTP) 405.2.1 Introduction 405.2.2 Community scale Reed Bed Treatment System (RBTS) of municipal wastewater

    415.2.3 Treatment Efficiency 425.2.4 Social Acceptance 435.2.5 Objectives 445.2.6 Area Selection 445.2.7 Process Design of WWTP 455.2.8 Preliminary Treatment 455.2.9 Primary Treatment 465.2.10 Secondary Treatment 465.2.11 Sludge Treatment 465.2.12 Formation of management committee 475.2.13 Financial Aspect 47


  • 6 Results and Discussion 48

    6.1 General 486.1.1 Legislation for prevention of pollution 486.1.2 Short Term and Long Term Strategy 516.1.3 Monitoring of Waste Water Management Systems 536.1.4 Sanitation Target and Achievement (10th Year Plan) (2002-2007) 546.1.5 Opinions of key Informant on the Rules and Regulations for WastewaterTreatment Plants 55

    6.2 Operation and maintenance of wastewater treatment plants 576.2.1 Conditions of Sewerage System 576.2.2 Blockage of the System 586.2.3 Hum