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WATER QUALITY
STANDARDS FOR COASTAL WATERS MARINE OUTFALLS
In a coastal segment marine water is subjected to several
types of uses. Depending on the types of uses and activities, water quality
criteria have been specified to determine its suitability for a particular purpose.
Among the various types of uses there is one use that demands highest level
of water quality/purity and that is termed a "designed best use" in
that stretch of the coastal segment. Based on this, primary water quality
criteria have been specified for following five designated best uses:
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Class
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Designated best
use
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SW-I (seeTable 1.1)
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Salt pans, Shell fishing, Mariculture and Ecologically
Sensitive Zone.
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| SW-II (seeTable 1.2)
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Bathing, Contact Water Sports and Commercial fishing.
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| SW-III (seeTable 1.3)
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Industrial cooling, Recreation (non-contact) and
Aesthetics.
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| SW-IV (seeTable 1.4)
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Harbour.
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| SW-V (seeTable 1.5)
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Navigation and Controlled Waste Disposal.
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The standards along with rationale/remarks for various
parameters, for different designated best uses, are given in Table 1.1 to
1.5. Table 1.1 Primary Water Quality Criteria For Class SW-I Waters
(For Salt pans,
Shell fishing, Mariculture and Ecologically Sensitive Zone)
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S.No.
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Parameter
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Standards
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Rationale/Remarks
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1.
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pH Range
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6.5 – 8.5
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General broad range, conductive for propagation of
aquatic lives, is given. Value largely dependent upon soil-water
interaction.
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2.
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Dissolved Oxygen
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5.0 mg/l or 60
percent saturation value, which-ever is higher.
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Not less than 3.5 mg/l at any time of the year for
protection of aquatic lives.
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3.
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Colour and Odour
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No Noticeable colour
or offensive odour.
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Specially caused by chemical compounds like creosols,
phenols, naptha, pyridine, benzene, toluene etc. causing visible
colouration of salt crystal and tainting of fish flesh.
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4.
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Floating Matters
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Nothing obnoxious or
detrimental for use purpose.
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Surfactants should not exceed an upper limit of 1.0 mg/l
and the concentration not to cause any visible foam.
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5.
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Suspended Solids
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None from sewage or
industrial waste origin
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Settleable innert matters not in such concentration that
would impair any usages specially assigned to this class.
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6.
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Oil and Grease (including Petrolium Products)
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0.1 mg/l
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Concentration should not exceed 0.1 mg/l as because it
has effect on fish eggs and larvae.
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7.
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Heavy Metals:
Mercury (as Hg)
Lead (as Pb)
Cadmium (as Cd)
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0.01
mg/l
0.01
mg/l
0.01
mg/l
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Values depend on:
(i) Concentrations in salt, fish and shell fish.
(ii) Average per capita consumption per day.
(iii) Minimum ingestion rate that includes symptoms
of resulting diseases.
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Note: SW-1 is desirable to be safe and relatively free
from hazardous chemicals like pesticides, heavy metals and radionuclide
concentrations. Their combined (synergistic or antagonistic) effects on
health and aquatic lives are not yet clearly known. These chemicals undergo
bio-accumulation, magnification, and transfer to human and other animals
through food chain. In areas where fisheries, salt pans are the governing
considerations, and presence of such chemicals apprehended/reported, bioassay
test should be performed following appropriate methods for the purpose of
setting case-specific limits
Table 1.2 Primary Water Quality Criteria for Class SW-II Waters
(For Bathing,
Contact Water Sports and Commercial Fishing)
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S. No.
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Parameter
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Standards
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Rationale/Remarks
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1.
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pH Range
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6.5 – 8.5
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Range does not cause skin or eye irritation and is also
conductive for propagation of aquatic life.
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2.
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Dissolved Oxygen
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4.0 mg/l or 50
percent saturation value, which-ever is higher.
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Not less than 3.5 mg/l at any time for protection of
aquatic lives.
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3.
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Colour and Odour
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No Noticeable colour
or offencive odour.
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Specially caused by chemical compounds like creosols,
phenols, naptha, pyridine, benzene, volume etc.
causing visible colouration of water and tainting of and odour in fish
flesh.
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4.
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Floating Matters
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Nothing obnoxious or
detrimental for use purpose.
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None in concentration that would impair usages specially
assigned to this class.
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5.
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Turbidity
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30 NTU (Nephelo
Turbidity Unit)
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Measured at 0.9 depth.
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6.
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Fecal Coliform
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100/100 ml (MPN)
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The average value not exceeding 200/100 ml. in 20
percent of samples in the year and in 3 consecutive samples in monsoon
months.
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7.
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Biochemical Oxygen Demand (BOD) (3 days at 27ºC)
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mg/l
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Restricted for bathing (aesthetic quality of water).
Also prescribed by IS:2296-1974
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Table 1.3 Primary Water Quality Criteria for Class SW-III Waters
[For Industrial
cooling, Recreation (non-contact) and Aesthetics]
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S.No
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Parameter
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Standards
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Rationale /
Remarks
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1.
|
pH Range
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6.5 – 8.5
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The range is conductive for propagation of aquatic
species and restoring natural system.
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2.
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Dissolved Oxygen
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3.0 mg/l or 40 percent saturation value, which-ever is
higher.
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To protect aquatic lives.
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3.
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Colour and Odour
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No Noticeable colour or offensive odour.
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None in such concentration that would impair usages
specifically assigned to this class.
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4.
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Floating Matters
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No visible / obnoxious floating debris, oil slick, scum.
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As in (3) above.
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5.
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Turbidity
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30 NTU
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Reasonably clear water for Recreation, Aesthetic
appreciation and Industrial cooling purposes.
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6.
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Fecal Coliform
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500/100 ml (MPN)
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Not exceeding 1000/100 ml in 20 percent of samples in
the year and in 3 consecutive samples in monsoon months.
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*7.
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Dissolved Iron (as Fe)
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0.5 mg/l or less
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It is desirable to have the collective concentration of
dissolved Fe and Mn less or equal to 0.5 mg/l to avoid scaling effect.
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*8.
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Dissolved Manganese (as Mn)
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0.5 mg/l or less
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* Standard included exclusively for Industrial Cooling
purpose. Other parameters same.
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Table 1.4 Primary Water Quality Criteria for Class SW-IV Waters
(For Harbour
Waters)
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S.No.
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Parameter
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Standards
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Rational /
Remarks
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1.
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pH Range
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6.5 – 9.0
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To minimize corrosive and scaling effect.
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2.
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Dissolved Oxygen
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3.0 mg/l or 40 percent saturation value, whichever is
higher.
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Considering bio-degradation of oil and inhibition to
oxygen production through photosynthesis.
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3.
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Colour and Odour
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No visible-colour or offensive odour.
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None from reactive chemicals which may corrode
paints/metallic surfaces.
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4.
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Floating Materials Oil, grease and scum (including
Petroleum products)
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10 mg/l
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Floating matter should be free from excessive living
organisms, which may clog or coat operative parts of marine
vessels/equipment.
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5.
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Fecal Coliform
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500/100 ml (PAN)
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Not exceeding 1000/100 ml in 20 percent of samples in
the year and in 3 consecutive samples in monsoon months.
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6.
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Biochemical Oxygen Demand (3 days at 27ºC
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0.5 mg/l or less
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To maintain water relatively free from pollution caused
by sewage and other decomposable wastes.
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Table 1.5 Primary Water Quality Criteria for Class SW-V Waters
(For Navigation and
Controlled Waste Disposal)
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S. No.
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Parameter
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Standards
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Rationale/Remarks
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1.
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pH Range
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6.0 – 9.0
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As specified by New England Interstate Water Pollution
Control Commission.
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2.
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Dissolved Oxygen
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3.0 mg/l or 40 percent saturation value, whichever is
higher.
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To protect aquatic lives.
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3.
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Colour and Odour
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None is such concentration that would impair any usages
specifically assigned to this class.
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As in (1) above.
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4.
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Sludge deposits, Solid refuse floating oil, grease &
scum.
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None except for such small solids, amount that may
result from discharge of appropriately treated sewage and/or individual
waste effluents.
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As in (1) above.
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5.
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Fecal Coliform
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500/100 ml (MPN)
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Not exceeding 1000/100 ml in 20 percent of samples in
the year and in 3 consecutive samples in monsoon months.
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Source Series: PCLS/4/2000-2001, CPCB, MOE&F, GOI,
July 2000.
For further details contact at the following e-mail
addresses: cpcb@alpha.nic.in cpcb@sansad.nic.in
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