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Water Quality Monitoringand
Assessment
Interrelationships betweenthe steps used in monitoring
Chemical Monitoring TechniquesBiomonitoring Techniques
Dr. Subodh Sharma 2
Interrelationships betweenthe steps used in monitoring
What type of monitoring is required?Biological:in-situ/ex situ tests?mortality/sub-lethal tests?whole organisms/sub-organism level?Bio-accumulation studies?biotic indices?Bio-monitors/bio-probes?Chemical:continuous? automatic?manual?What determinands/tests/assays, etc. are required?What level of accuracy is required?What sampling methodology / deployment regime should be used:frequency?time(s) of day?sampling sites?
What information is required to fulfil the aims of the sampling programme?
What decisions are to be made on the basis of these results?
What resources are available?
Strictly define monitoring programme
What is the best way to interpret the results?What is the best way to present the results?
Result output and presentation REVIEW
Dr. Subodh Sharma 3
Chemical Monitoring Techniques
Design of monitoring1. Purpose of Monitoring2. Sampling sites3. Sampling frequency (daily/yearly/seasonal)4. Sampling methodology5. Choice of appropriate analytical
methodology
1.Purpose/Types of monitoringa. Cause and effect monitoringb. Baseline monitoringc. Compliance monitoringd. Inventory monitoring
Station A
Station B
Treatment
2. Sampling sites
Fig. An example of site selectionin cause and effect monitoring
Dr. Subodh Sharma 4
Chemical Monitoring Techniques
4. Sampling methodologya). Laboratory sample processing
Sample-A1 Litre Sample-B
1 Litre
2 6431 5 7 850ml 120ml 100ml 100ml 100ml 100ml
Filter
Absor-bances
pHCond.Turb.
Freeze Filter/Freeze
Filter/Chill
Filter/Chill
In Lab.
Immediately
Few days/week
Within 3 months
Within 1 yearTN, TP NH4, NO3, Cl, SO4
SO4 Ca, Mg, Na, K
350ml 200ml350ml 100ml 100ml
BOD5 BOD5 Alk. Freeze
Filter/ Freeze
TN, TP NH4, NO3, Cl, SO4
From Smith & McBride 1990
Dr. Subodh Sharma 5
Random sampling.Time weighting Random samplingTime weighting Systematic sampling.
Chemical Monitoring Techniques
3. Automatic : Automatic samplers are used for the collection of routine samples. Eg, 100 ml. sub-samples collected every 5 h into a single container, with a new sampling vessel selected every 25 h.
2. Continuos : Best used for measuring pH and DO, where manual samplecollection is extremely expensive. Equipment are available for ammonium,temperature, turbidity, and chlorophyll-a is currently being developed.
4. Sampling methodologyb). Sampling Process
1. Manual
Dr. Subodh Sharma 6
Case study from Galaudu Pokhare Khola subwatershed
Dr. Subodh Sharma 7
Objectives of the study
Objective 1:To survey, identify and map potential water sources and sites for water harvesting.
Objective 2: To assess sedimentation problem in the two river systems (Galaundu and Pokhare Khola) and establish relationships between land use, biological indicators and water quality.
Objective 3:To develop management schemes for water harvesting and conservation and for optimising water use.
Dr. Subodh Sharma 8
Study Area
27°40´ to 28°14´ N and 84°0´ to 85°1´ETotal area: 27.09 sq. km.Major rivers: Galaundu and Pokhare KholaPopulation: 5305
Dr. Subodh Sharma 9
Methodology
Temperature, pH, conductivity, and dissolvedoxygen were analyzed on site.
Hardness, inorganic ions, heavy metals(Chromium, Copper, Zinc, Lead and Nickel) wereanalyzed in laboratory.
For the Presence/Absence (P/A) test of bacteria in water, two methods were used, such as HiMedia’s user friendly PA Coliform Test Kit (MS1186) and Hydrogen Sulphide Test using test strip in vials.
Dr. Subodh Sharma 10
Results & Discussion
Stagnant water springs
(Kuwa)18%
Taps45%
Ponds3%
Tanks3%
Streams6%
Running water springs (Dhara)
25%
Dr. Subodh Sharma 11
pH
Minimum 5.63(in taps)
Maximum 11.0 (in stream)
Dr. Subodh Sharma 12
Temperature
Minimum 19.0 deg. Celsius
(in stream)
Maximum 24.8 deg. Celsius
(in pond)
Dr. Subodh Sharma 13
Conductivity
Minimum 3.85 μS/cm.(in taps)
Maximum 975 μS/cm.(in taps)
Dr. Subodh Sharma 14
DO
Minimum 0.10 mg/L.(in dhara)
Maximum 6.20 mg/L.(in taps)
Dr. Subodh Sharma 15
Magnesium
Minimum 0.88 mg/L.(in kuwa)
Maximum 20 mg/L.(in taps)
Dr. Subodh Sharma 16
Calcium
Minimum 3.2 mg/L. (in stream)
Maximum 102 mg/L. (in taps)
Dr. Subodh Sharma 17
N-NO2
Minimum 0.00 mg/L.(in stream)
Maximum 0. 054 mg/L.(in stream)
Dr. Subodh Sharma 18
N-NO3(WHO recommended maximum permissible level is 25 mg/L)
Minimum 0.05 mg/L(in Dhara)Maximum 2.4 mg/L(in Dhara)
Dr. Subodh Sharma 19
ChromiumWHO recommended maximum permissible level is 50 μ g/L)
Minimum 1 μg/L.(in taps)
Maximum 15.8 μg/L.(in Dhara)
Dr. Subodh Sharma 20
Copper
Minimum 2.4 μg/L.(in stream)
Maximum 20 μg/L.(in taps)
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ZincWHO recommended maximum permissible level is 3000 μ g/L)
Minimum 28 μg/L.(in Dhara)
Maximum 124 μg/L.(in Spring)
Dr. Subodh Sharma 22
LeadWHO recommended maximum permissible level is 10 μ g/L)
Minimum 1.28 μg/L.(in kuwa)
Maximum 30 μg/L.(in taps)
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NickelWHO recommended maximum permissible level is 20 μ g/L)
Minimum 1.54 μg/L.(in taps)
Maximum 54 μg/L.(in stream)
Dr. Subodh Sharma 24
Dr. Subodh Sharma 25
Conclusions and Recommendations
pH values were usually higher in the area studied indicating high calcium contents in water .
At this stage, there appears to be no problem of nitrate indrinking water supply, however source protection toprevent likely contamination from agricultural runoff mustbe given priority.
A proper selection of GI pipes is recommended when used inpublic drinking water systems.
The use of lead pipes in pipelines in the presence of corrosivewaters has resulted in higher lead concentrations at thetap in the area studied.
Dr. Subodh Sharma 26
Bio-monitoring techniques
PRINCIPLES OF BIO-MONITORING:• The first category comprises the Bio-assays (Experimental)
• Eco-toxicological tests, bio-accumulation tests, bio-degradation tests, eutrophication tests.
• The second category comprises the Bio-assessments (Observational)• taxa density, taxa richness, proportion between the communities.
ADVANTAGES:• Biological communities act as continuous monitors.• Biological communities respond to a wide range of different water
quality.LIMITATIONS:
• Specific cause of the change is not identifiable.• A comprehensive assessment demands considerable effort in
sampling.
Dr. Subodh Sharma 27
Use of different taxonomic groupsin bio-monitoring
Bacteria algae Macro-invertebrates
Macro-phytes
fish Birds/mammals
Aquatic zone(water body)
++ - / + ++ - / + ++ +
Riparian zone(banks)
_ - + ++ + ++
Terrestrial zone(floodplains)
_ - + ++ _ ++
- = not suitable + = suitable ++= well suitable
Dr. Subodh Sharma 28
Advantages of using Benthicmacro-invertebrates
Good indicators of localized conditions.Integrate the effects of short-term environmental variations.Easily identifiable to family level.Sampling is relatively easy.Serve as food for fish.Are abundant in most streams.
Dr. Subodh Sharma 29
Advantages of using Fish
Fish are good indicators of long-term effects.Fish community structure is reflective of integrated environmental health.Fishes are at the top of the aquatic food chain and are consumed by humans.Relatively easy to collect and identify.
Dr. Subodh Sharma 30
Advantages of using Algae
Algae are good indicators of short-term impacts.Algae are primary producers.Sampling is easy, inexpensive, requires few people.Relatively standard methods exist for characterizing algal communities.Algal communities are sensitive to some pollutants.
Dr. Subodh Sharma 31
Principal approaches to assess water quality
Saprobic approach• is based on the pollution tolerance of the
indicator species present.Diversity approach uses three components• richness• evenness• abundance
Biotic approach• incorporates quantitative measure of species
diversity with qualitative information on the sensitivity of indicator species.
Dr. Subodh Sharma 32
The Saprobic Index
S = ∑ (s.h)/ ∑hwhere S = Saprobic Index, s = saprobic value for each indicator species,
h = frequency of occurrence of each species.the value of S normally ranges from 1 to 4 for ambient waters.
Major criticisms of saprobic systems:The taxonomy is not far enough advanced.The pollution tolerances of species are very subjective.No information on the community as a whole is provided.
Dr. Subodh Sharma 33
The Diversity Index
H’ = ∑ Νι/Ν log2 Νι/Ν where H’ = index value, N = total number of individuals of all species collected, and Ni= number of individuals belonging to the ith species.
They are strictly quantitative.Relatively independent of sample size.Assumptions made are highly subjective.
Dr. Subodh Sharma 34
Biotic IndicesTrent biotic index
England(1964)
Chandler’s ScoreScotland(1970)
BMWP ScoreUK
(1978)
Modified BMWP Score
UK(1979)
Extended Biotic Index
UK(1978)
Chutter’s Biotic Index
South Africa(1972)
Hilsenhoff’s Biotic IndexUK
(1977)
Hilsenhoff’s ImprovedBiotic Index
USA(1987)
Indice BiotiqueFrance(1968)
Indice Biologiquede Qualite GeneraleFrance(1982)
Indice BiologiqueGlobalFrance(1985)
Belgian Biotic Index
Belgium(1983)NEPBIOS
Nepal(1996)
Dr. Subodh Sharma 35
Comparison betweenTrent and Extended Biotic Index
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO WOODIWISS, 1978
I I-II II II-III III III-IV IV
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO WOODIWISS, 1964
I I-II II II-III III III-IV IV
Dr. Subodh Sharma 36
Comparison betweentwo French Indices
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO TUFFERY &
VERNEAUX, 1968
I I-II II II-III III III-IV IV
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO TUFFERY &
DAVAINE, 1970
I I-II II II-III III III-IV IV
Dr. Subodh Sharma 37
Comparison betweenFrench and Belgian Biotic
Indices
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO AFNOR, 1985
I I-II II II-III III III-IV IV
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO DE PAUW &
VANHOOREN, 1983
I I-II II II-III III III-IV IV
Dr. Subodh Sharma 38
Comparison between British & American Indices
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO EXTENCE et al.,
1887
I I-II II II-III III III-IV IV
0102030405060708090
Tota
l Site
s
CALCULATED WATER QUALITY ACCORDING TO HILSENHOFF, 1988
I I-II II II-III III III-IV IV
Dr. Subodh Sharma 39
Conclusions & Recommendation
Biological assessment methods are an integral part of river water quality monitoring.It is recommended that sampling methods be standardized.Where river conditions permit, benthic macroinvertebrates should be used.Every country should establish its index system.In large rivers colonization samples should be used.Other indicator organisms should also be used.
End of Lecture-3