255.1 93EV Final Report LIBRAP~Y INTERNATK~NAL ~EFE~~CE C~NTJ~B FOR COMMUNITY WATER SUPPLY ANI SANITATI~N(IRC~ Evaluation of Four Slow Sand Filter Plants in Andhra Pradesh Sponsor: Netherlands Assisted Projects Office, Hyderabad National Environmental Engineering Research Institute Nehru Marg, Nagpur - 440 020 December 1993 255. 1—12238 — — — — — — — — — — — — — — — — — — — — Evaluation of Four Slow Sand Filter Plants in Andhra Pradesh po~1, Sponsor Netherlands Assisted Projects Office, Hyderabad LIBRARY, INTERNATIONAL REFERENCE CENTRE FOR COMMUNITY WATER SUPPLY AND SANITATION (IRC) PD. Box 93190,.. 2509 AD The Hacju~ .~ Tel. (070) 814911 ext. 141/142 RN: I2-23&~.. ~ LO: ~j~j ~ National Environmental Engineering Research Institute Nehru Marg, Nagpur - 440 020 December 1993 — — — — — — — — — — — — — — — — — — — — FOREWORD The Netherlands Government, under its bilateral assistance programme, has been providing since 1979, financial support to the Government of Andhra Pradesh in the implementation of rural watersupply schemes. The first phase of the programme, termed as AP-I covering 201 villages has been completed in 1992. The AP-Il programme initiated in 1988 covering 288 villages is under implementation. The programmes are coordinated by the Netherlands Assisted Projects Office (NAPO) at Hyderabad. The periodic review and support missions organised by the Royal Netherlands Embassy (RNE), New Delhi, obseived that the slow sand filters built under AP-l are not functioning with maximum efficiency. The January, 1993 mission recommended that detailed investigations be undertaken by experienced Indian consultants in close cooperation with Panchayat Raj Engineering Department (PRED). In pursuance of this recommendation, the NAPO, Hyderabad retainedthe NationalEnvironmental Engineering Research Institute (NEERI), a constituentlaboratoryofCSIR to carryout a critical evaluation of the functioning of four slow sand filters atA.B. Pa/em, Darsi, Vinukonda and Pothunuru with a view to suggest recommendations for improvements in construction and operation and maintenance of slow sand filters (SSF). This reportpresents a review ofSSF design and construction practice followed by PRED, an indepth assessment of the performance of the identified slow sand filters, an appraisal of the operation and maintenance practices, and the knowledge base of the plant and supervisory staff with special reference to SSF. Recommendations have been delineated to bring about improvement in source protection, design, construction, opera- tion and maintenance of slow sand filters. The Cooperation and assistance rendered byNAPO and PRED engineers and other field staff in the evaluation study is gratefully acknowledged. Nagpur (R. PARAMASIVAM) December, 1993 Coordinator PROJECT PERSONNEL Mr. Elyas, S.I. Mr. Rama Rao, K.G. Mr. Rammohan Rao, I. Mr. Ravindar Rao, R. Ms. Shinde, A.B. COMPUTER ASSISTANCE Mr. Krishna Kumar, C. Mr. Sankaran, V.K. PROJECT LEADER Dr. Reddy, R.C. PROJECT COORDINATOR(S) Dr. Paramasivam, R. Dr. Vittal Rao, M. DIRECTOR Dr. Khanna, P. RESOURCE PERSONNEL NETHERLANDS ASSISTED PROJECTS OFFICE Er. K. Naram Adviser (Till Sept. 1993) Mr. Henk op het Veld Team Leader Ms. Rebecca Secretary PANCHAVAT RAJ ENGINEERING DEPARTMENT Er. R. Kondala Rao Engineer-in-chief Er. K. Thirupathaiah Superintending Engineer Er. K.V. Rangam Setty Executive Engineer CONTENTS SI. Title Page No. List of Figures (I) List of Tables (ii) List of Annexures (iii) 1. PREAMBLE 1 2. RURAL WATER SUPPLY IN ANDHRA PRADESH 1 3. THE NETHERLANDS ASSISTED PROJECTS (NAP) 2 IN ANDHRA PRADESH 4. BACKGROUNDTOTHE PRESENT STUDY 2 5. TERMS OF REFERENCE 3 6. METHODOLOGY 4 7. BRIEF DESCRIPTION OF THE SCHEMES EVALUATED 5 7.1 A.B. Palem 5 7.2 Darsi 6 7.3 Vinukonda 11 7.4 Pothunuru 11 8. EVALUATION FINDINGS 17 8.1 A.B. Palem 17 8.2 Darsi 26 8.3 Vinukonda 32 8.4 Pothunuru 36 8.5 Parchur 42 8.6 Jagirla Madugu 42 SI. Title Page No. 9. A CRITIQUE OF THE FINDINGS 44 9.1 Source Protection 44 9.2 Intake Location 45 9.3 Filter Design 46 9.4 Number and Size of Filter Beds 46 9.5 Filtration Rate 47 9.6 Filter Sand 47 9.7 Mode of Filter Operation 48 9.8 Inlet Arrangements 48 9.9 Outlet Arrangements 49 9.10 Filter Cleaning and Resanding 52 9.11 Safety Chlorination 52 9.12 Training 53 9.13 Community Education and Participation 53 10. SUMMARY 54 10.1 General 54 10.2 Engineering Aspects 54 10.3 Management Aspects 55 11. RECOMMENDATIONS 55 11.1 Engineering Aspects 55 11.2 Management Aspects 56 ANNEXURES 58 I LIST OF FIGURES Fig. Title Page No. 1. Central Protected Water Supply Scheme- 7 A.B. Palem 2. Central Protected Water Supply Scheme- Darsi 10 3. Protected Water Supply Scheme- Vinukonda 14 4. Protected Water Supply Scheme- Pothunuru 18 5. Typical Inlet Arrangement for Slow Sand Filter 50 6. Typical Outlet Arrangement for Slow Sand Filter 51 (I) I I I I LIST OF TABLES Table Title Page No. 1. Salient Features of SSF Plant at A.B. Palem 8 2. Salient Features of SSF Plant at Darsi 12 3. Salient Features of SSF Plant at Vinukonda 15 4. Salient Features of SSF Plant at Pothunuru 19 5. Physico-chemical and Bacteriological Quality of Raw and 22 Filtered Waters- A.B. Patem (Date of sampling : 6-4-1993) 6. Physico-chemical and Bacteriological Quality of Raw and 23 Filtered Waters- A.B. Palem (Date of sampling : 6-7-1993) 7. Sieve Analysis of Filter Sand- A.B. Palem 25 8. Physico-chemical and Bacteriological Quality of Raw and 29 Filtered Waters- Darsi (Date of sampling . 7-4-1993) 9. Physico-chemical and Bacteriological Quality of Raw and 30 Filtered Waters- Darsi (Date of sampling 8-7-1993) 10. Sieve Analysis of Filter Sand- Darsi 31 11. Physico-chemical and Bacteriological Quality of Raw and 34 Filtered Waters- Vinukonda (Date of sampling : 8-4-1993) 12. Physico-chemical Quality of Raw Water- Gundlakamma 35 River Bed (Vinukonda) (Date of sampling : 8-4-1993) 13. Sieve Analysis of Filter Sand- Vinukonda 37 14. Physico-chemical and Bacteriological Quality of Raw and 39 Filtered Waters- Pothunuru (Date of sampling : 9-4-1993) 15. Physico-chemical and Bacteriological Quality of Raw and 40 Filtered Waters- Pothunuru (Date of sampling : 9-7-1993) 16. Sieve Analysis of Filter Sand- Pothunuru 41 17. Sieve Analysis of Filter Sand- Parchur 43 (H) I LIST OF ANNEXURES Annexure Title Page I Proforma for Collection of Engineering and Technical Data for 58 Evaluation of Slow Sand Filters II Design of Slow Sand Filters at A.B. Palem 64 ill Design of Slow Sand Filters at Darsi 66 IV Recommended Design Criteria for Slow Sand Filters for 68 Rural Water Supply (iii) 1. PREAMBLE Provision of safe drinking water in adequate quantity is a basic necessity for the well being and socio-economic development of a community. Throughout the developing world, supply of potable water to rural population has been a challenging task. In India, water supply programmes form a part of National Development Plans and are implemented in a phased manner under the Five Year Plans. A number of departments and ministries ofthe central and state governments have been vested with the responsibility for water supply and sanitation. With the advent of International Drinking Water Supply and Sanitation Decade (1981-90), the rural water supply programme received a great impetus. In order to further accelerate the pace of coverage, the Government of India launched in 1986, the Technology Mission on drinking water for villages and related water management with the objective of covering all the residual problem villages with safe drinking water by 1990 through cost effective technologies. 2. RURAL WATER SUPPLY IN ANDHRA PRADESH In the state of Andhra Pradesh, the Panchayat Raj Engineering Department (PRED) is the implementing agency for all rural development schemes such as roads, buildings, and water supply and sanitation. The water supply and sanitation programmes are looked after by a separate Chief Engineer. While at the middle level the Panchayat Raj Engineers deal with all the developmental schemes, separate staff is deployed at the field level for water supply and sanitation programmes. Rural water supply schemes are funded mainly under the Accelerated Rural Water Supply (ARWS) programme and the Minimum Needs Program (MNP) of Govt. of India. Due to inherent advantages of slow sand filters over conventional rapid sand filters, the PRED, Government of Andhra Pradesh has designed and constructeda number of slow sand filters for rural water supply schemes in the state. I 3. THE NETHERLANDS ASSISTED PROJECTS (NAP) IN ANDHRA PRADESH The Netherlands Government, under its bilateral assistance programme has been providing since 1979, financial support to the’ Government of Andhra Pradesh in the implementation of rural water supply schemes. The programmes are co-ordinated by The Netherlands Assisted Projects (NAP) office at Hyderabad. The first phase of the programme, termed AP-I and covering 201 villages has since been completed in 1992. The AP-li programme initiated in 1988 and covering 288 villages is under Implementation. The AP-I schemes are based on both surface and subsurface sources whereas AP-Il schemes utilise only surface waters. Under AP-l programme, wherever surface (canal) water is used as a source, summer storage tanks are provided to tide over the canal closure period. The stored water is treated in slow sand filters and chlorinated before supply. In AP-Il schemes, rapid sand filters or slow sand filters are used depending upon the site specific conditions. Rapid sand filters have been preferred for comprehensive protected water supply schemes with a common surface source serving a cluster of villages. 4. BACKGROUND TO THE PRESENT STUDY During the half yearly Review and Support Missions organised by the Royal Netherlands Embassy in India, it has been noticed that the slow sand filters built under AP-I, are not functioning with maximum efficiency and output, thereby resulting in less water supply, particularly to the tail end areas.