Sri Lanka Sri Lankan sets ambient water quality standards

The government of Sri Lanka promulgated the National Environmental (Ambient Water Quality) Regulations, No. 01 of 2019 on November 5, 2019. No pollutant shall be discharged into inland surface water in excess of the ambient water quality standards specified in the Schedule to the regulations. The ambient water quality standards specify discharge limits for pollutants for each of the following six water quality categories.

Category A: Water that requires simple treatment (simple filtration and boiling at 100 degrees Celsius) for drinking

Category B: Bathing and recreational water

Category C: Water suitable for aquatic life

Category D: Water source that requires general treatment process for drinking

Category E: Water suitable for irrigation and agricultural activities

Category F: Water with minimum quality that does not fall into categories A to E

 

Schedule: Ambient water quality standards (excerpt)

No.

Parameter Unit A B C D E

F

General

4

TSS mg/l, max 25 40 1,500 2,100

Nutrient

10

NO3 -N mg/l, max 10 10 10 10

10

Other

13

Chloride (CI) mg/l, max 250 250 600

Metal

17

Cd, total µg/l, max 5 5 5

5

23

Hg, total 1 1 1 1 2

2

26

Zn, total 1,000 1,000 1,000 2,000

24,000

28

As, total 50 50 50 50 50

50

Organic Micro Pollutant

30

Phenolic compounds µg/l, max 2 5 2 5 5

5

Micro Organism

35

Total Coliform MPN/100ml, max 10,000 10,000 10,000

 

The National Environmental (Ambient Water Quality) Regulations, No. 01 of 2019 can be downloaded from the following URL.
http://www.cea.lk/web/images/pdf/epc/2148-20_E-1.pdf