What is essential for the decentralized waste water management? Experience of Japan, Malaysia, India

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1 What is essential for the decentralized waste water management? Experience of Japan, Malaysia, India April 2, 2015 Kazushi HASHIMOTO Adviser Japan Sanitation Consortium 1 Decentralized Wastewater Treatment System (DEWATS) 1 Septic Tank 2 1

2 Decentralized Wastewater Treatment System (DEWATS) 2 BORDA DEWATS 3 Decentralized Wastewater Treatment System (DEWATS) 3 Packaged Aerated Wastewater Treatment Plant (PAWTP Johkasou in Japan) 4 2

3 Comparison of DEWATS Treatment Process Effluent Water Quality (BOD) Nitrogen removal CAPEX per person in developing countries Septic Tank BORDA DEWATS PAWTP (Johkasou) Anaerobic (Electricity not required) Anaerobic (Electricity not required) Aerobic (Electricity required) mg/l 50 mg/l 20 mg/l Not removed Not removed Removed US$ US$ US$ What happens, if DEWATS is not regularly desludged? Any wastewater treatment system ceases to treat and becomes a pollution source. 6 3

4 What happens, if Septic Tank is not regularly desludged? 1 If the septage volume exceeds one-third the capacity of the tank, solid-liquid separation decreases since the retention time of the wastewater decreases. BOD removal is hampered since the inflow of wastewater agitates the accumulated sludge causing inflow wastewater to pass through the tank without treatment. Moreover, a part of the accumulated sludge in the tank flows out together with the untreated wastewater, leading to further deterioration in the water quality of the effluent of the septic tank. (Source : USAID) 7 Black water only type 1 Black water only type 2 Black water only type 3 Black & Grey type 1 Black & Grey type 2 Black & Grey type 3 (Source : JICA) What happens, if Septic Tank is not regularly desludged? 2 No septic tank meets the effluent standard established by the Governor of Jakarta City Government for household septic tank (BOD75mg/l, COD100 mg/l). Irregular desludging may be one of the causes. Volume ( m3 ) Usage (persons) Effluent water quality Remarks BOD COD mg/l mg/l Desludged once a year Desludged twice a year Never desludged Not desludged (4 years) Not desludged (3 years) Not desludged (3 years) 8 4

5 What happens, if PAWTP (Johkasou) is not regularly desludged? 1 Sludge accumulates quickly in a PAWTP since its wastewater treatment efficiency is high. It must be desludged once a year to maintain its performance standard. After one year After three years 9 What happens, if PAWTP (Johkasou) is not regularly desludged? 2 A research, conducted in 1984 for 70 PAWTPs (black water only type) in Japan, revealed that 24.6% of them had not been desludged for more than 1 year, and their average effluent water quality (BOD) was worse than the ones which had been desludged with less than 1 year intervals BOD COD SS NH4-N NO2,3-N 0 <6 Month 6-12Month 12-18Month 10 5

6 BORDA DEWATS I wonder how to desludge this system?? 11 What is essential for the decentralized wastewater management? Introduction of regular desludging system. Proper disposal of the sludge removed from DEWATS. Septage Management! 12 6

7 What is essential for the introduction of regular desludging system? Desludging must be the legal obligation of all the owners of any DEWATS. There must be the trained good desludging operators. Formalize them, if there are existing desludging operators. Let them make companies. Establish the licensing system and training system. Data base of all DEWATS in the City. Both the municipality and the desludging operators should have it. Use vacuum truck for the more efficient and hygienically safer de-sludging operation. Use the sludge relay tank to shorten hauling time. Improve the DEWATS for the efficient desludging. Necessity of Regulatory Framework for Septage Management Residents do not worry about the septic tank unless it becomes full of sludge, overflow and their toilet becomes unusable. Communication strategy is necessary but not enough. Regulation is necessary. 14 7

8 For good Septage Management, these peoples are the most important!!! Existing desludging operators in Mizoram State, India, who are conducting desludging of septic tanks using a pump and a water tank mounted on a truck. PAWTP De-sludging Technician PAWTP Inspector 15 Economics of Regular Desludging The most expensive item for septage management is not the DEWATS itself but the cost for desludging. Desludging of one septic tank (3 m3 ) costs US$30 in Jakarta, US$50 in India, US$70 in Malaysia, US$250 in Japan. In Japan, the desludging is considered not a profitable business unless at least 4 PAWTPs can be desludged by one vacuum truck. Efficiency matters. In Japan, many desludging operators cover 7 PAWTPs daily and make money. 8

9 Technology for the efficient Septage Management 1 Use of Vacuum Truck will ensure the efficient and hygienically safe desludging operation. Time required for emptying Discharge of the sludge Possibility of the human contact with the pathogen Vacuum Truck Septic tank (3m3) 40 minutes PAWTP (5PE) 30 minutes 10 minutes -Quick because the caliber of the hose is bigger (45-65mm) None Truck + pump Septic tank (3m3)-2 hours 30 minutes -Slow because the caliber of the hose is smaller (32mm) Possible at the time of connecting and disconnecting the hose to the tank. These vacuum trucks shall be leased to the existing desludging operators. (Photo taken in Mizoram State, India) Technology for the efficient Septage Management 2 Sludge relay tank will improve the efficiency of desludging operation by shortening the hauling time. 9

10 DEWATS must be desludging friendly It must be reachable for the desludging operators. (1) It must be installed in the open air space. (2) It must have manholes. It would be the most convenient if the partial desludging could effectively remove all the sludge without removing the water contents. In case of septic tank, you need to remove all the contents of the tank. 10

11 In case of PAWTP, the partial desludging effectively removes all the sludge. The water contents of the tank does not need to be removed. Proper disposal of the sludge removed from DEWATS (1) Local municipality s obligation to develop septage/sludge treatment facility. Central government s obligation to provide financial support to Local municipalities. (2) Sludge drying bed is an appropriate method if land is available. (3) If there is a Sewage Treatment Plant (STP) nearby, cotreatment at the excess sludge treatment section of a sewage treatment plant is the best option. Proper pretreatment facility is required to minimize the adverse effect on the operation of STP. (4) Independent septage/sludge treatment facilities - In Japan, there are 1,100 independent night soil/sludge treatment plants of various technologies

12 Warning! Establishing a workable Septage Management may be the most difficult development agenda. Only two countries have a nation wide Septage Management System. Japan Malaysia (partial success) 23 Septage Management System based on PAWTP (Johkasou) Technology in Japan In Japan, PAWTPs (black water only type) had been widely difused since 1960s. In 1970s 1980s, water pollution of rivers and oceans had become a big issue. Particularly, the cause of eutrophication occurred in lakes and inland bays was attributed to the poor performance and maintenance of PAWTPs (black water only type). Only after the promulgation of PAWTP (Johkasou) Act in 1983, the maintenance of PAWTPs in Japan improved and eutrophication of lakes and inland bays in Japan stopped. The new installation of PAWTP (black water only type) was banned and PAWTP (both black water and grey water type) has become the standard DEWATS in Japan

13 Main points in the PAWTP Act (1983) (1) Item Manufacturing and Installation of PAWTPs Maintenance of PAWTPs Desludging of PAWTPs Inspection of PAWTPs What does the PAWTP Act stipulate? The PAWTP (black + gray water type) is the standard on-site wastewater treatment facility in Japan. PAWTPs shall meet the technical standards for effluent water quality and the structural standards prescribed in the Building Standard Law. The owner of a PAWTP is designated as the PAWTP Manager who is legally responsible for the maintenance of the PAWTP. The PAWTP Manager shall make the PAWTP receive inspection, maintenance and desludging. The PAWTP Manager can outsource the work related to PAWTP management to a PAWTP vendor and/or a PAWTP desludging vendor. The PAWTP Manager shall ensure that the PAWTP receives desludging service once a year. The PAWTP Manager shall make the PAWTP receive an inspection for its water quality annually by the Specified Inspection Agency. 25 Main points in the PAWTP Act (1983) (2) Item Desludging Business Maintenance Business What does the PAWTP Act stipulate? A corporate body that intends to join the PAWTP desludging business shall get the approval from the mayor of the municipality for a limited period. The applicants need to conform to the standards for approval stipulated in the PAWTP Law. A corporate body that intends to join the PAWTP maintenance business shall register to the municipality concerned. The PAWTP maintenance vendor shall assign its staff qualified as PAWTP Operator who has passed a national examination or completed a training course conducted by a designated training agency, to the PAWTP maintenance work

14 Number of people engaged in the Septage Management Business in Japan People with qualification (Number of registrants) PAWTP Operators PAWTP Installation Workers PAWTP Technical Supervisors PAWTP Desludging Technicians PAWTP Inspectors 72,521 Operation and maintenance 83,205 Installation/ Construction 26,658 Management of PAWTP with 501 PE or more 15,117 Desludging 1,210 Total 198,711 Number of vendors Specified inspection agencies PAWTP manufacturers PAWTP maintenance vendors PAWTP desludging vendors PAWTP installation vendors 65 PAWTP inspection and water quality examination 27 Research, development and manufacture 12,871 Operation and maintenance 5,375 Desludging 33,593 Installation/ construction 27 Malaysia s effort toward establishing effective Septage Management System 1 In 1993, Sewerage Services Act (SSA) federalized the sewerage assets, thus empowering the Malaysian Government to regulate this industry. SSA also provided the fundamental policies for septage management. In 1994, Indah Water Konsortium (IWK) was created as the private concessionaire who was responsible for O/M of all sewerage facilities, and septage management. By these reforms, Sewerage coverage ratio : 25% (1993) 70% (current) Desludging coverage ratio : 1% (1993) 12.4% (1999) On the other hand, the newly introduced sewerage charges (including desludging charges) for individuals and businesses caused complains from the Malaysian population and refusal to pay. As a result, tariffs were reduced at a level too low to cover operation expenditures

15 Malaysia s effort toward establishing effective Septage Management System 2 In 2000, IWK was nationalized. In 2006, SSA was replaced by the Water Service Industry Act (WSIA). National Water Services Commission (SPAN) was created to regulate water and sewerage services. In the area of Septage Management, the IWK s responsibility for the desludging and maintenance of the individual septic tank was transferred to the owner or residents of a premise, who are legally responsible for engaging IWK (Service licensee) or a license permit holder both regulated by SPAN to desludge and maintain their septic tanks. Fines up to US$ 15,000 was established against the noncompliance, which have not been imposed yet. 29 Malaysia s effort toward establishing effective Septage Management System 3 The number of desludged septic tanks has substantially decreased since No IST IST DEMAND DESLUDGING No IST 450, , , , , , , ,000 50,000 0 IST SCHEDULED DESLUDGING Year 70,000 60,000 50,000 40,000 30,000 20,000 10, Year Total Attempted Total Unsuccessful Total Desludged 30 15

16 No. of IST 2015/3/29 Malaysia s effort toward establishing effective Septage Management System 4 Desludging campaigns are being organized to incite septic tank owners/users to desludge within the legal interval. 160, , Jumlah No. Tangki of IST Septik desludging yang dinyahenap done cemar Desludging Campaign at:- a) Taiping, Perak b) Kangar, Perlis c) Melaka d) Yong Peng, Johor e) Simpang Renggam, Johor 120, ,000 80, , ,000 20, Desludging Campaign at:- a) Muar, Johor b) Temerloh, Pahang c) Kubang Pasu, Kedah d) Port Dickson, Negeri Sembilan e) Sungai Besar, Selangor Year Malaysia s effort toward establishing effective Septage Management System 5 Ms. Y. B. Dato Noriah Kasnon, Deputy Minister for Energy, Green Technology, and Water, joined a desludging campaign organized by SPAN and IWK and operated the lever of vacuum track

17 Malaysia s effort toward establishing effective Septage Management System 6 Decrease of desludging activities has been affecting the river water quality. RIVER WATER QUALITY BASED ON BIOLOGICAL OXYGEN DEMAND Lessons from experiences of Japan and Malaysia Any on-site wastewater treatment facility becomes pollution source without proper Septage Management. In order to do Septage Management, you must be real serious. It is a highly political issue. In Septage Management, without proper regulation, nobody does the right thing. In Septage Management, the people who do the actual work are the most important. Regulate them. Formalize them. Respect them. Septage Management will create a lot of job opportunities. It is good for the economy at national and local levels

18 Thank you for your attention!