Laboratory testing of water quality parameters

Testing of Physical, Chemical, Biological and Radioactive substances.

1. L aboratory 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 :  H 2 O Molar mass :  18.01528 g/ mol Boiling point :  100 °C Melting point :  0 °C

3. 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.

4. Total dissolved solids  ( TDS ) are a measure of the combined content of all inorganic and organic substances contained  in a  liquid in molecular, ionized or micro-granular (colloidal sol) suspended form. ... Whereas Total Suspended Solids ( TSS ) are solids in water that can be trapped by a filter .

5. 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)

6. EC METER

7. A measure of acidity or alkalinity of water soluble substances ( pH  stands for 'potential of Hydrogen '). A   pH  value is a number from 1 to 14, with 7 as the middle (neutral) point. Values below 7 indicate acidity 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 . p H

8. 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.

9. Alkalinity contd …

10. 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:

11. IMPORTANCE OF HARDNESS

12. AMMONIA IN DRINKING WATER

13. BLUE BABY SYNDROBE DUE TO – NO3

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

15. 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.

16. 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.

17. BIOACCUMULATION & BIOMANIFICATION.

18. BOD

19. 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.

20. COD

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

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

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

24. MPN Table for presumptive coliforms test

25. THANK YOU