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Water Quality Criteria for Fresh Water Aquatic Resources


Appropriated Water Quality Criteria for Aquatic Living
No. Water Quality Index Unit Appropriated Concentration Remark
1. Temperature ° C 23 - 32 Naturally Changed and not Rapid Change
2. pH - 5 - 9 Daily Change should not exceed 2.0 Unit
3. Dissolved Oxygen (DO) mg/l. Minimum 3 -
4. CO2 mg/l Maximum 30 and DO sufficiency
5. Turbidity
- Transparency
- Suspended solids

cm.
mg/l.

30 - 60
Maximum 25

Secchi disc

Sources: Academic Paper   from Thailand Fresh Water Fishery Institute  Issue 75/2530 Item Water Quality Criteria for Fresh Water Aquatic Resources


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Maximum Concentration Allowance in the Water
No. Water Quality index Unit Maximum Concentration Allowance Remark
1. Heavy Metals
- Cadmium (Cd)
- Copper (Cu)
- Lead (Pb)
- Mercury (Hg)
- Iron (Fe)
- Zinc (Zn)

mg/l
"
"
"
"
"

0.001
0.02
0.05
0.0005
0.3
0.1
-
2. Organochlorine Compounds
- DDT
- Dieldrin
- Endrin
- Heptachlor

mg/l
"
"
"

0.5 x 10-3
0.2 x 10-2
0.01 x 10-3
0.4 x 10-3
-
3. Organophosphate Compounds
-Fenitrothion
- Malathion
- Methyl parathion
- Parathion

mg/l
"
"
"

0.06
0.02
0.2
0.04
-
4. Carbamate Compounds
- Carbaryl
- Carbofuran

mg/l
"

0.01
0.008
-
5. Herbicides
- Glyphosate
- Paraquat
-Propanil
- 2, 4-D

mg/l
"
"
"

4.8
0.5
0.5
45.0
-
6. NH3-N mg/l 0.02 un-ionized ammonia
7. Chlorine mg/l 0.005 Total residual chlorine
8. Detergent
- Soft detergent
- Hard detergent

mg/l
"

0.03
0.5

Surfactant
9. Sulfide mg/l 0.2 undissociated
hydrogen sulfide

Sources: Academic Paper  from Thailand Fresh Water Fishery Institute  Issue 75/2530 Item Water Quality Criteria for Fresh Water Aquatic Resources Preservation


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