Challenges in Wastewater Treatment and Management in Asia:

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Clifford Gibson
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1 Challenges in Wastewater Treatment and Management in Asia: Sewered vs Non-sewered Solutions Thammarat Koottatep 1

2 What happens after flushing the toilet? 2

3 6 L per time (35 Lcpd) 2 L per time (23 Lcpd) Current solutions all have significant limitations Current solutions, both centralized and decentralized, have significant limitations that jeopardize health and safety and, in many cases, perpetuate open defecation practices. HANGING TOILETS PIT LATRINES SEPTIC TANKS SEWERAGE Foul odors Poor user experience Safety hazards Environmental contamination Expensive to install, maintain Require infrastructure Require considerable water Treatment not assured Bill & Melinda Gates Foundation 6 3

4 Faecal Sludge Management (FSM) Effluent Faecal sludge Sewer Faecal Sludge Management (FSM) Effluent 250 Baht/cu.m. Clogging Bad smell Sewer 4

5 Faecal Sludge Management (FSM) FS Treatment Plant Faecal Sludge Management (FSM) FS Treatment Plant Only 15% transported to FS treatment plant 5

6 What happens 85%? 6

Black water 30/11/60 Domestic wastewater Management in Thailand: Daily

Building effluent standard BOD < 30 mg/l 1.4 million cu.m. (14.

treatment Real estate effluent standard BOD < 30 mg/l Manhole 9.6 million cu.

4%) Effluent standard BOD < 20 mg/l 90% Cesspool Or 8% Commercial package

Faecal Sludge Andaman Sea Gulf of Thailand FS treatment plant 80% Anaerobic

under IMPROVEMENT AND CONSERVATION OF THE NATIONAL ENVIRONMENTAL QUALITY ACT,

7 Black water 30/11/60 Domestic wastewater Management in Thailand: Daily production Household or Small building >100 households 10 types of Building Building effluent standard BOD < 30 mg/l 1.4 million cu.m. (14.6%) 101 plants Central wastewater treatment system Or Grey water Onsite treatment Real estate effluent standard BOD < 30 mg/l Manhole 9.6 million cu.m Combined sewerage system 8.2 million cu.m (85.4%) Effluent standard BOD < 20 mg/l 90% Cesspool Or 8% Commercial package Ministerial regulation under Building control Act BOD < 30 mg/l (Environment) Faecal Sludge Andaman Sea Gulf of Thailand FS treatment plant 80% Anaerobic Digester Emptying truck Building effluent standard Ministerial regulation under IMPROVEMENT AND CONSERVATION OF THE NATIONAL ENVIRONMENTAL QUALITY ACT, B.E (1992) 44 th and 51 st Ministerial regulation under Building control Act (Adapted from building effluent standard Size C and D) 7

8 Building effluent standard Parameters Unit Sizing of Building A B C D E 1. ph BOD mg/l Solids 3.1 Suspended Solids mg/l Settleable Solids ml/l Total Dissolved Solids* mg/l Sulfide mg/l TKN mg/l Fat, oil & Grease mg/l *Total Dissolved Solids is increased from normal value in tap water Parameters Real estate effluent standard Unit Sizing of Real estate households > 500 households 1. ph BOD mg/l Solids 3.1 Suspended Solids mg/l Settleable Solids ml/l Total Dissolved Solids* mg/l Sulfide mg/l TKN mg/l Fat, oil & Grease mg/l *Total Dissolved Solids is increased from normal value in tap water 8

5 billion US Types of WWTP Stabilization Pond 46 plants Aerated Lagoons 16 plants Activated sludge (Oxidation ditch) 36 plants RBC 1 plant

9 Centralized Wastewater treatment plant Total 101 WWTP in Thailand Completed 96 plants Under Construction 4 plants Suspended 1 plant Total construction cost 83 billion Baht 2.5 billion US Types of WWTP Stabilization Pond 46 plants Aerated Lagoons 16 plants Activated sludge (Oxidation ditch) 36 plants RBC 1 plant Constructed wetland 2 plants Centralized wastewater treatment effluent standard Parameters Unit Value 1. ph BOD mg/l <20* 3. Suspended Solids mg/l <30 (<50 for SP) 4. TN mg/l <20 5. TP mg/l <2 6. Fat, oil & Grease mg/l <5 *Filtrated BOD for stabilization pond 9

10 Water Quality in major rivers What happens if only having toilets but no proper treatment?? Sludge direct to the environment when no service chain 20% WC to sewer 79% On-site facility Safely emptied Unsafely emptied Left to overflow or abandoned Leakage Illegally dumped Effectively treated Not effectively treated 2% of fecal sludge 2% safely disposed of fecal sludge 98% unsafely disposed 1% Open defecation Source: WSP analysis, using BMGF funded research 1% 69% Residential environment 9% 9% 1% 9% Drainage systems Receiving waters Bill & Melinda Gates Foundation 20 10

Health status in Thailand Diarrhea morbidity

600,000 400,000 200,000 0 1990 1991 mortality

1998 1999 2000 2001 2002 Source: Ministry of

200 100 0 Diarrhea mortality cases Thank You

11 Health status in Thailand Diarrhea morbidity cases 1,400,000 1,200,000 1,000, , , , , mortality Year morbidity Source: Ministry of pubic health (Thailand), Diarrhea mortality cases Thank You We create a bridge for sanitation innovations 11

. ARUSHA URBAN WATER SUPPLY AND SANITATION AUTHORITY (AUWSA)

. ARUSHA URBAN WATER SUPPLY AND SANITATION AUTHORITY (AUWSA) ENVIRONMENT STATISTICS IN SUPPORT OF THE IMPLEMENTATION OF THE FRAMEWORK FOR THE DEVELOPMENT OF ENVIRONMMENT (FDES 2013) PRESENTED BY MKAMA