Testing of Physical, Chemical, Biological and Radioactive substances.

1. Laboratory testing of water quality
parameters
GYANENDRA BAHADUR KARKI
MANAGER
WATER QUALITY DIVISION,KUKL

2. INTRODUCTION
 Water is a transparent, tasteless, odourless,
and nearly colourless chemical substance that
is the main constituent of Earth's streams,
lakes, and oceans, and the fluids of most living
organisms
 Density: 997 kg/m³
 Formula: H2O
 Molar mass: 18.01528 g/mol
 Boiling point: 100 °C
 Melting point: 0 °C

5. TURBIDITY
 Turbidity is a
cloudy appearance
of water caused by
small particles
suspended therein.
 Turbidity has no
health effects.
However, turbidity
can interfere with
disinfection because
the particles can act
as shields for
viruses and bacteria
and provide a
medium for
microbial growth.
Turbidity may
indicate the
presence of disease
causing organisms.

6. Total dissolved
solids(TDS)are a
measureof the
combined contentof all
inorganicand organic
substances
containedin a liquid in
molecular,ionized or
micro-granular
(colloidalsol)
suspended form....
WhereasTotal
Suspended Solids
(TSS)are solids in
waterthatcan be
trappedby a filter.

7.  Total Dissolved Solids (TDS) consist mainly of
Carbonates, DISSOLVED Bicarbonates, Chlorides,
Sulfates, Phosphates, Nitrates, Calcium, Magnesium,
SOLIDS Sodium, Potassium, Iron, Manganese, and a few
others. They do not include gases, colloids, or
sediment.
 The TDS can be estimated by measuring the specific
conductance of the water.
 Dissolved solids in natural waters range from less than
10 mg/l for rain to more than 100,000 mg/l for brines.
Since TDS is the sum of all materials dissolved in the
water, it has many different mineral Sources.
TOTAL
DISSOLVED
SOLIDS
(TDS)

8. EC METER

10. • A measureof acidityor alkalinityof watersoluble
substances(pH standsfor'potentialof Hydrogen').
A pH value is a number from1 to 14, with7 as the
middle(neutral)point.Values below 7 indicateacidity
which increases as the number decreases, 1 being the
most acidic.
 The pH of pure water is 7.
 In general, water with a pH lower than 7 is
considered acidic, and with a pH greater than 7 is
considered basic.
 The normal range for pH in surface water systems
is 6.5 to 8.5, and the pH range for groundwater
systems is between 6 to 8.5.
pH

14. ALKALINITY
 Alkalinity refers to the capability of water to
neutralize acid.
 This is really an expression of buffering
capacity.
 A buffer is a solution to which an acid can be
added without changing the concentration of
available H+ ions (without changing the pH)
appreciably.

15. Alkalinity contd…

16. Hardness of Water
Definition CaCO3 Concentration
Soft Water 0 – 60 milligrams per liter
(mg/L)
Moderately Hard 61 – 120 mg/L
Hard 121 – 180 mg/L
Very Hard 181 or above
Water hardness is an aesthetic quality of water, and is caused mostly
by the minerals calcium and magnesium, but is classified or measured
based on the level of concentration of calcium carbonate.
How hardness is classified is based on the following scale:

17. IMPORTANCE OF
HARDNESS

18. AMMONIA IN
DRINKING
WATER

19. BLUE BABY
SYNDROBE DUE
TO – NO3

20. HOW DO
NITRATES EFFECT
THE HEALTH OF
AQUATIC
ANIMALS?

21. BLUE BABY
Syndrome
 Blue baby syndrome can also be caused
by nitrates in drinking water leading to
methemoglobinemia.
 Nitrates from polluted drinking water
form compounds in the body that change
haemoglobin to methemoglobin,
decreasing the ability of blood to carry
oxygen.
 In infants, the condition can be fatal.

23. EUTROPHICATION
 Eutrophication (from Greek eutrophos, "well-
nourished"), or hypertrophication, is when a body
of water becomes overly enriched with minerals
and nutrients that induce excessive growth of plants
and algae.
 This process may result in oxygen depletion of the
water body.
 One example is the "bloom" or great increase of
phytoplankton in a water body as a response to
increased levels of nutrients. Eutrophication is
almost always induced by the discharge of nitrate
or phosphate-containing detergents, fertilizers, or
sewage into an aquatic system.

26. BIOACCUMULATION &
BIOMANIFICATION.

27. BOD

28. How to
measure
BOD?
 Measure the volume of a sample of water
in a dark bottle. Measure its oxygen level
by oxygen meter? Chemical method.
 Incubate the water at 20◦C in dark to
prevent photosynthesis for 5 days.
 Measure the oxygen level again.
 The difference between 2 oxygen level is
BOD.

33. COD

38. Monitoring Water Quality
Field Test
Laboratory Analysis
Laboratory
Analysis
Chemical and Microbiological

39. Microbiological Analysis: Coliform Count
1. Membrane Filter Technique

43. MacConkey Broth containing
water sample
Sample showing Coliforms
after incubation
2. MPN(Most Probable Number) Technique

44. MPN Table for presumptive coliforms test

45. THANK YOU