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Surface Water


Surface Water Quality

Classification and Objectives
Classification Objectives/Condition and Beneficial Usage
Class 1 Extra clean fresh surface water resources used for :
  1. conservation not necessary pass through water treatment process require only ordinary process for pathogenic destruction
  2. ecosystem conservation where basic organisms can breed naturally
Class 2 Very clean fresh surface water resources used for :
  1. consumption which requires ordinary water treatment process before use
  2. aquatic organism of conservation
  3. fisheries
  4. recreation
Class 3 Medium clean fresh surface water resources used for :
  1. consumption, but passing through an ordinary treatment process before using
  2. agriculture
Class 4 Fairly clean fresh surface water resources used for :
  1. consumption, but requires special water treatment process before using
  2. industry
Class 5 The sources which are not classification in class 1-4 and used for navigation

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Surface Water Quality Standards
Parameter Units Statistics Standard Value for Class Methods for Examination
Class 1 Class 2 Class 3 Class 4 Class 5
1. Color, odor, taste - - n n n n - -
2. Temperature Co - n' n' n' n' - Thermometer
3. pH - - n 5-9 5-9 5-9 - Electrometric pH Meter
4. Dissolved Oxygen mg/l P20 n 6 4 2 - Azide Modification
5. BOD (5 days, 20oC) mg/l P80 n 1.5 2.0 4.0 - Azide Modification at 20 o C , 5 days
6. Coliform bacteria Multiple Fermentation Technique
- Total coliform MPN/100 ml P80 n 5,000 20,000 - -
- Fecal coliform MPN/100 ml P80 n 1,000 4,000 - -
7. NO3 -N mg/l Max. allowance n 0.5 - Cadmium Reduction
8. NH3-N mg/l - n 0.5 - Distillation Nesslerization
9. Phenols mg/l - n 0.005 - Distillation,4-Amino antipyrene
10. Copper (Cu) mg/l - n 0.1 - Atomic Absorption -Direct Aspiration
11. Nickle (Ni ) mg/l - n 0.1 - Atomic Absorption -Direct Aspiration
12. Manganese (Mn) mg/l - n 1.0 - Atomic Absorption -Direct Aspiration
13. Zinc (Zn) mg/l - n 1.0 - Atomic Absorption -Direct Aspiration
14. Cadmium (Cd) mg/l - n 0.005*
0.05**
- Atomic Absorption -Direct Aspiration
15. Chromium Hexavalent mg/l - n 0.05 - Atomic Absorption -Direct Aspiration
16. Lead (Pb) mg/l - n 0.05 - Atomic Absorption -Direct Aspiration
17. Total Mercury mg/l - n 0.002 - Atomic Absorption-Cold Vapour Technique
18. Arsenic (As) mg/l - n 0.01 - Atomic Absorption-Gaseous Hydride
19. Cyanide (CN) mg/l - n 0.005 - Pyridine-Barbituric Acid
20. Radioactivity
- Alpha
-Beta

Becqurel/l
Becqurel/l

-
-

n
n

0.1
1.0

-
-
Low Background Proportional Counter
21.Total Organochlorine
Pesticides)
mg/l - n 0.05 - Gas-Chromatography
22. DDT µg/l - n 1.0 - Gas-Chromatography
23. Alpha-BHC µg/l - n 0.02 - Gas-Chromatography
24. Dieldrin µg/l - n 0.1 - Gas-Chromatography
25. Aldrin µg/l - n 0.1 - Gas-Chromatography
26. Heptachlor & Heptachlorepoxide µg/l - n 0.2 - Gas-Chromatography
27. Endrin µg/l - n none - Gas-Chromatography

Remark : P Percentile value
n naturally
n' naturally but changing not more than 3 o C
* when water hardness not more than 100 mg/l as CaCO 3
** when water hardness more than 100 mg/l as CaCO 3
Based on Standard Methods for the Examination of Water and Wastewater recommended by APHA : American Public Health Association, AWWA : American Water Works Association and WPCF : Water Pollution Control Federation
Source: Notification of the National Environmental Board, No. 8, B.E. 2537 (1994), issued under the Enhancement and Conservation of National Environmental Quality Act B.E.2535 (1992), published in the Royal Government Gazette, Vol. 111, Part 16, dated February 24, B.E.2537 (1994).


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Chao Phraya River Water Quality Standards
Control Areas
(km. from River Mouth)
Water Quality Standards
(Same as Standards of Water Classification)
7 - 62 Class 4
62- 142 Class 3
142 - 379 Class 2

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 111, Part 62, dated August 4, B.E.2537 (1994).

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Thachin River Water Quality Standard
Control Areas
(km. from River Mouth)
Water Quality Standards
(Same as Standards of Water Classification)
0 - 82 Class 4
82- 202 Class 3
202 - 325 Class 2

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 111, Part 62, dated August 4, B.E.2537 (1994).

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Bang Pakong, Nakorn Nayok, and Prachinburi River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
- Bang Pakong River
from river mouth to Bansang, Prachinburi Province
Class 3
- Nakorn Nayok River
from Bansang, Prachinburi Province to Amphur Muang, Nakorn Nayok Province
Class 3
- Nakorn Nayok River
from Bansang, Prachinburi Province to Amphur Muang, Prachinburi Province
Class 2

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 111, Part 62, dated August 4, B.E.2537 (1994).


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Maeklong River Water Quality Standard
Control Areas
(km. from River Mouth)
Water Quality Standards
(Same as Standards of Water Classification)
0 -140 Class 3

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 111, Part 62, dated August 4, B.E.2537 (1994).

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Songkram River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
from Ta-uten, r Province to Sohpisai , Nongkai Province Class 3

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 115, Part 72, dated September 8, B.E.2541 (1998).


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Phong River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
from Kosoompisai, Mahasarakarm Province to Ubonrat Dam, Khonkhean Province Class 3

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 116, Part 53, dated July 6, B.E.2542 (1999).


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Chi River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
from Warinchamrab, Ubonratchatani Province to Bankwao, Chaiyaphum Province Class 3

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 116, Part 53, dated July 6, B.E.2542 (1999).

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Moon River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
from Kongjuim, Ubonratchatani Province to Chokchai, Nakhonratchasima Province Class 3

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 116, Part 53, dated July 6, B.E.2542 (1999).

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Lamtakong Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
from the conjunction with Moon River in Amphur Muang, Nakhonratcharatsima Province (km. 0) to Khonchum Dike in Amphur Muang , Nakhonratchasima Province (km. 24) Class 4
from Khonchum Dike in Amphur Muang , Nakhonratchasima Province (km. 24) to Pakchong,Nakhonratchasima Province (km. 180) Class 3

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 116, Part 53, dated July 6, B.E.2542 (1999).

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Phetchaburi River Water Quality Standard
Control Areas
(km. from River Mouth)
Water Quality Standards
(Same as Standards of Water Classification)
0 - 61 Class 3
61- 118 Class 2

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 116, Part 72, dated September 9, B.E.2542 (1999).


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Tapi River- Phum Duang River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
-Klong Phumduang
from the conjunction with Tapi River and Phumduang River in Amphur Punpin, Surattani Province (km.0) to Ratchaprapa Dam, in Bantakhun, Surattani Province (km.121)
Class 3
- Tapi River
from River mouth in Amphur Muang,Surattani Province (km.0) to Amphur Chawang, Surattani Province (km.184)
Class 3
- Tapi River
from Banwungmaung in Amphur Chawang,Surattani Province (km.184) to Amphur Phipoon, Surattani Province (km.221)
Class 2

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 117, Special Part 10, dated February 2, B.E.2543 (2000).

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Pattani River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
from river mouth (km.0) to Yarang, Pattani Province (km.19) Class 3
from Yarang, Pattani Province (km.19) to Banglang Dam in Bannang, Yala Province (km.128) Class 2

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 116, Part 72, dated September 9, B.E.2542 (1999).


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Pak Phanang River Water Quality Standard
Control Areas Water Quality Standards
(Same as Standards of Water Classification)
from river mouth to Maisieb Dam in Cha-ued,Nakhonsrithammarat Province Class 3

Source: Notification of Pollution Control Department, published in the Royal Government Gazette, Vol. 116, Part 72, dated September 9, B.E.2542 (1999).

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Restricted Zone for Protecting the Source of Water Supply in Bangkok Metropolitan Region

1) Restricted Zone for Protecting of the BMR Water Supply B.E. 2522 (1979) and 2531 (1988)
The Cabinet decided to protect the source of the Bangkok Metropolitan Region (BMR) Water Supply by expanding the restricted zone of Samlae Catchment area from 200 square kilometers to 350 square kilometers in accordance with the recommendation of NEB (National Environmental Board). This regulation requires that in the restricted zone, the building an expansion of factories which discharge wastewater continuing toxic substances listed below or organic matter exceeding one kilogram of BOD per day, will not be permitted. The mentioned toxic substances include
a) Heavy metal : Zinc, Cromium, Copper, Mercury, Manganese, Cadmium, Lead, Nickle, Barium, and Iron
b) Other Toxic Substances : PCB( Polychlorinated biphenyl), Cyanide, Arsenic , Selenium, Phenols, etc.
 
Source: The Cabinet Resolution dated April 17, B.E. 2522 (1979) and January 12, B.E.2531 (1988)
 

2) Restricted Zone for Protecting of BMR Water Supply at the Western part of the Chao Phraya River B.E.2535 (1992)

The cabinet decided to protect the sources of the Bangkok Metropolitan Region (BMR) Water Supply be expanding the restricted zone of the western part of the Chao Phaya River which effects water quality at Klong Mahasawas and the Thachin River which have an area of 485 square kilometers, on recommendation of NEB. The areas covered Bangkok Metropolitan, Nontaburi Province and Nakornpatom Province. The pollution sources control are as follows :
a) Industrial activities containing high concentration of toxic substances are not permitted to be established and/or expanded
b) Domestic wastewater must be treated to meet the standards
c) Agricultural waste must be treated, which include highly polluted sources, such as fish ponds and swine farms
 
Source: The Cabinet Resolution dated February 11, B.E. 2535 (1992)


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