ON SITE DOMESTIC WASTEWATER
ON-SITE
TREATMENT IN THAILAND
Dr. Variga Sawaittayotin
Environmental Research and Training Center,Center
Department of Environmental Quality Promotion
Dr. Chaiyo Juisiri
Domestic Wastewater Department
Pollution Control Department
Ministry of Natural Resources and Environment, Thailand

Workshop
p on On-site Domestic Wastewater Treatment in Asia
November 20-21, 2013, Tokyo, Japan

Population

 64,623,000 million
 City = 29,662,000 million
 Local area = 34,961,000 million

Surface Water
Resources in Thailand

Surface Water Resources:
divided into 25 River Basins1Salaween14 Mae Klong

2gKhong

15 Prachinburi

3Kok

16 Bang Pakong

4Chi

17 Tonele Sap

5Mun

18 Eastern Coast

6gPing19 Phetchaburi

7Wang

20 Western Coast

8Yom

21 SouthSouth-East
East Coast

9Nan

22 Tapiy
10 Chao Phraya

23 Songkhla Lake

11 Sakae Krang

24 Pattani

12 Pasak25 SouthSouth-WestWest
Coast

13 Tha Chin

3The main reason causing water quality deterioration,
considering from the parameters, was due to thewastewater from communities. This also included
wastewater from other activities, such as industrial
activities
andagricultures
which
dischargedwastewater to water sources without prior water
treatment. As a solution to these causes, there should
be campaign encouraging the public to reduce water
usage ini orderdt reduce
tod
wastewatertt
andd tot manage
wastewater at the point source by treating thewastewaterfromhouseholdandrecycling
thewastewater.

The main reason causing water quality deterioration, considering fromthe parameters, was due to the wastewater from communities.
As a solution to these causes, there should be campaign encouraging
the public to reduce water usage in order to reduce wastewater andto manage wastewater at the source by treating the wastewater fromhousehold and recycling the wastewater. The local government should
construct community wastewater treatment system.

Following by- charge a fee for wastewater treatment- encourage the business owners to apply clean technologies- enforce wastewater treatment before draining to the environment- control low quality water drainage through irrigation or agriculturalareas to reduced- enforce the law on the drainage water standard

Status of Municipal Wastewater Treatment
Facilities in Thailand

Location of 101 Municipal
Wastewater Treatment
Facilities in Thailand
Constructed 92 Plants

Under Construction 8 Plants

Delayed (Samutprakan Province)
1 Plant

99

Technology for Wastewater Treatment
Facilities in Thailand

Municipal Wastewater Treatment
Systems defined by System

Types of Collection Systems
Central Wastewater Treatment

Combined Sewer System

Design Criteria for Central
Wastewater Treatment
Th type off
Thecollection
systems
Combined Sewer
System
Separate Sewer
Systemdrain both runoff andsewerage within one
systemBOD

SS(mg/l)(mg/l)

Separate Sewer System

65 - 110(80)

40 – 110(80)

sewerage and runoff arecollected in separate pipingsystems

(160)

(160)

Number and Capacity of Municipal Wastewater Treatment System

The collection of wastewater treatment
feeSources of Water Pollution

Domestic :Industry : 1,687 Municipalities,
 6,089 LAOs,
 BMA,BMA Pattaya City Approximately 9.8 M m3/d

 >120,000 factories
 Approximately 2.8 M m3/d

Agriculture : Pig
Pi farm+fAquaculture
Al(Point(P i source)) 0.1
0 1 M m3/d
 Paddyfield (Non Point source)
150 M m3/d

14

Municipal Wastewater Managementin Thailand(1,687) Municipalities

MWW~2.5 M m3/dBMA, Pattaya City

MWW. ~2.5 M m3/d(6,089) LAOs

MWW~ 9.0 M m3/dTreatment capacity ~ 3.2

Total MWW~14M m3/day

M m3/d(~ 22.
22.9% of total MWWMWW))

Total BOD Loading~ 2,600 Ton
T BOD/day
BOD/dTotal Budget 83,83,152 M Baht

The Main Problem

Municipal Wastewater Management in Thailand
M i i l Wastewater:
MunicipalWastewater
W tt
 is one of the most serious environmental problems in Thailand.
 approximately 14 M m3/day of municipal wastewater generated by
the population around the country in year 2008, including : 1,687 Municipalities
 6,089
6 089 LAOLAOs
 BMA, Pattaya City

~ 2.5 M m3/d~ 9.0
9 0 M m3/d
~ 2.5 M m3/d

 101 Municipal Wastewater Treatment Facilities in the country havebeen constructed (approximately 3.2 millions m3/day or app 22.9 %of total wastewater treated)

Constraints in Municipal Wastewater
Management in Thailand
Constraints :Many urban communities lack appropriate municipal
wastewater management

The communities and people still lack understandingin wastewater problem and awareness to protect theenvironmentThe local administration organizations are still unableg municipal
p wastewater
to manage

Lack of budget for construction of the newwastewater collection system and wastewater
facilities

Operational Problems of Municipal Wastewater Treatment System
1. Operation and Maintenance.
2. Management of Central System and Wastewater Treatment.
Communities’ Involvement in the Central
3. Promotional Campaign and Communities
Wastewater Treatment System Management.
4. Law Enforcement, Regulating Mechanism, and Driving Local Administration
to Act Progressively.
gy
5. TARGETThe Main Problem in Wastewater Facilities ManagementWeak Wastewater : the systems are sized
to treat highly diluted wastewater
Sewerage leakage : pumped mains
experienceisubstantialbi l leakage
l kwithihpotential
poe a contamination
co aa o ofo groundwaterg ou dwa e
Sewer sedimentation : high levels ofi t i andd low
intrusion
l hydraulich d li profiles
fil ini
gravity sewers.

The Main Problem in Wastewater Facilities Management

Staff skills : the treatment technologies require a high levelof skilled operator more difficult to resource up-country.
Operational cost : Electrical costs are particularly high.
Tariff charges : as a result of the low perceived benefit andlocal political considerations, progress in levying tariffs has
been limited to 3 municipalities to date.
dateSolution Problem on Domestic Wastewater Management

Structure of Municipal Sewage Management
System (MSMS)(2008

Term of MSMS2008
MSMS2008
PolicyImplement
Check &Correction

ActionHuman resource

Evaluation

Planning

Bring Back Better
Natural Water resources25

Reduce waste at pollution sources by the simple technologies (Ex. Grease
Trap and On-site treatment)Rehabilitate the existing municipal wastewater facilities

Construct new wastewater treatment system using appropriate technologyPolluter Pay Principal (PPP)Alternatives for Municipal Wastewater
Management in Thailand
On-site,(individual house)
Cluster Wastewater Treatment(Group of House)

Centralized Wastewater Treatment(High density)26

On-siteHousehold Wastewater Treatment

alized Wastewater
ment

Cluster Wastewater Treatment

Household Wastewater Treatment
Washer
LandOld House

Filtration
Kitchen

Oil Trap

PublicDrainageToiletSepticp Tank
WasherPublicDrainage

New House

Kitchen
Oil TTrap
ToiletWastewater
Treatment UnitLandFiltration

HouseholdshowerToilet
WasherKitchenพฤศจิกายน 56

รวมท่อมา
เข้าถังเกรอะ
30

Treatment SystemCollection SystemAnaerobic
outletToiletSepticOil trap

Oil Trap
washerShower

Ko Chang (Trat Province)
Flow 1- 3 m3/d
BOD 200 mg/L

Inf.

Ko Chang : Anaerobic Filter (AF)

Septic
AF 1

AF 3

AF 2Eff.

BOD <30 mg/L

Construction Cost 32,200 - 61,600 Baht

Media3333

Cost comparison
between centralized and onsite systems

Cost per hhouse

Centralized type cost curveHousehold type cost curve

Density of houseWater Pollution Control Policy
 Reduce wastewater at pollution sources bysimple technologies (Ex. Grease Trap andOn-site treatment) Rehabilitate the existing municipal
wastewater facilities Construct new wastewater treatment systemusingtechnologies
i appropriatei
h l i
 Polluter Payy Principalp ((PPP))35

Wastewater Management Law
LRegulation
Rl tiandd Enforcement
E ft Measures
M: The Enhancement and Conservation of National
Environmental Quality Act
Act, B
B.E.
E 2535 (NEQA 1992)
 Water Quality Standards : Ambient Water Quality Standards
 Effluent Standards
 Other Laws

 Management Measures : Monitor and Evaluate Water Quality
 Pollution ControlCZone Investment Measures : Establish Wastewater Treatment Facilities
36

Challenges in Municipal Wastewater
M
Managementiin Thailand
Th il dChallenges :Review current status and update the data ofexisting wastewater collection network and thed idrainagesystemtPropose and assess technically and economicallyfeasible options for Centralized, Cluster and Onsite
of wastewater treatment system, including
identifying types, separate sewage system, orcombined sewer system
which are appropriateforypp pLAOs

38

The current study of fenton ball researchin the constructed wetland of ERTC

39

Testing of Onsite Commercial Wastewater
Treatment Unitsvarious types of commercial
wastewater treatment tanks
are sold in markets
No procedure of testing andnone government authority
to guarantee the efficiencyof tank.
Because of the lack oftechnical data to support
ppaverification system

Experimental Set up and operation
Experimentconditions

durationO
Operationti
condition
diti

No. ofsampling

Start up3
monthsInfluent flow rate 1,000
1 000
L/d ( 10%)

 5 times

Normalsituation
it ti3months
thInfluent flow rate 1,000
L/d (( 10%)

 5 times- 2 times ofnormal

2months

Influent flow rate 2,000
2 000
L/d ( 10%),
5 consecutive days andrun in
i normall situationit ti

 5 times- A half ofnormal

2monthsInfluent flow rate 500 L/d( 10%),
5 consecutive days andrun in normal situation

 5 times- No
N iinfluent
flt

2months

fl5 consecutive
istop flowdays and run in normalsituation

 5 times
tiStress situation

Results
 Stress tests do not have effects on removal
efficiencies of BOD of the tested tanks.
tanks
 Removal efficiencies of BOD are in therange of 61-77
61 77 % and the average is 68 %.
% BOD in effluents are in the range of 42-74
mg/L.
mg/L
 For TKN, Phosphorus, sulfide and TDS
removal efficiency couldn’t
couldn t well so should
add secondary treatment to increase
removal efficiency.
42

Support system by government

 Design by PCD
 Consulting
 Reduce pollutant from wastewater on-site
P ll t P
P i i l PPP Polluter
Pay Principal:
 Discharge standard

Popular on-site treatment technology

 Treatment tank
 Septic tank
 Grease tab tank

Challenges to promote on-site
on sitewastewater treatment in Thailand

Low cost
Maintenancesystem
M i
30 Baht/month/46

We acknowledge
g the valuable assistance of
PCD and ERTC staffs for results and recommendations