Control of water pollution

Presented by Rekha 4th semester

26 February 2015 BBAU Lucknow.

WASTEWATER

NEED FOR WATER MANAGEMENT Today we all are facing the biggest problem that is scarcity of drinking water as the

level of water is continually decreasing. In many countries people die because of contaminated water as they do not have any

water resources that contain pure water. The first question comes in mind when we talk about water management is how can we

manage water. For this we need some well-planned strategies like if we know the places where heavy rainfall occur, then we can put extra efforts there in order to save water for future use.

Thousands of gallons of water can be saved if we keep our drainage system proper. Many non-profit organizations are coming forward and they approach people for the

noble cause of saving water. They educate people that how they can manage and save water in their homes. A lot of

water gets wasted due to leakage in water pipes. If we check all pipes and connections timely, then we can avoid leakage problems.

Bringing AwarenessMeasure 1 is bringing awareness among people. So people must be against of dumping wastes and sewage in to fresh water. They must force the government to go for an alternate way like treating the sewage before dumping. And people who dump wastes must be penalised.

PREVENTION OFWATER POLLUTION

Leakages from Drainage Pipe LinesLeakages from drainage pipe lines must be avoided. If this enters fresh water it causes water pollution. So leakages must be avoided by repairing immediately.

Industrial WastesIndustrial wastes are  the main cause of water pollution.  They often dump all these wastes in to near by lakes or rivers. So government must pass strict orders not to dump wastes in to rivers. They must be provided with other options like treatment of that wastes before dumping.

DON’T Use too much PesticidesFarmers must take care and see that they don't use too much pesticides. This will prevent runoffs of the material into nearby water sources.

Avoid Paint and Petroleum to SinksDo not throw paints or petroleum products in to your toilets or sinks. Since paints and petroleum products cannot be treated they should not be dumped to sewage water as it results in long lasting effects

Avoid Oil Spills in OceansOil spills in ocean are one of the major contributors of water pollution. So ships must transport oil only when weather conditions are good. During storms ships must not be allowed to transport oil which might result in shipwrecks and eventually oil spills.

GANGA ACTION PLANThe Ganga Action Plan or GAP was a program launched by Rajiv Gandhi in 1986 in order to reduce the pollution load on the river.

Human waste- domestic usage like bathing, laundry and public defecationIndustrial waste-dumping untreated waste into it.

Religious events -During festival seasons, people bathe in the Ganges to cleanse themselves from their sins.. A Hindu belief is that dropping the ashes of cremated bodies (at Varanasi) in the Ganges would give Moksha (liberation) to the jiva (soul).

Characteristics Designated best useA B C D E

Dissolved Oxygen (DO)mg/l, min 6 5 4 4 -Biochemical Oxygen demand (BOD)mg/l, max 2 3 3 - -Total coliform organisms MPN/100ml, max 50 500 5,000 - -pH value 6.5-8.5 6.5-8.5 6.0-9.0 6.5-8.5 6.0-8.5Colour, Hazen units, max. 10 300 300 - -Odour Un-objectionable   - -Taste Tasteless - - - -Total dissolved solids, mg/l, max. 500 - 1,500 - 2,100Total hardness (as CaCO3), mg/l, max. 200 - - - -Calcium hardness (as CaCO3), mg/l, max. 200 - - - -Magnesium hardness (as CaCO3), mg/l, max. 200 - - - -Copper (as Cu), mg/l, max. 1.5 - 1.5 - -Iron (as Fe), mg/l, max. 0.3 - 0.5 - -Manganese (as Mn), mg/l, max. 0.5 - - - -Cholorides (as Cu), mg/l, max. 250 - 600 - 600Sulphates (as SO4), mg/l, max. 400 - 400 - 1,000Nitrates (as NO3), mg/l, max. 20 - 50 - -Fluorides (as F), mg/l, max. 1.5 1.5 1.5 - -Phenolic compounds (as C2H5OH), mg/l, max. 0.002 0.005 0.005 - -Mercury (as Hg), mg/l, max. 0.001 - - - -Cadmium (as Cd), mg/l, max. 0.01 - 0.01 - -Salenium (as Se), mg/l, max. 0.01 - 0.05 - -Arsenic (as As), mg/l, max. 0.05 0.2 0.2 - -Cyanide (as Pb), mg/l, max. 0.05 0.05 0.05 - -Lead (as Pb), mg/l, max. 0.1 - 0.1 - -Zinc (as Zn), mg/l, max. 15 - 15 - -

Water Quality Standards in India (Source IS 2296:1992) 

Parameter World Health Organization European Union United States China

Arsenic 10μg/l 10 μg/l 10μg/l 50μg/lAntimony ns 5.0 μg/l 6.0 μg/l “Boron 2.4mg/l 1.0 mg/L “ “Cadmium 3 μg/l 5 μg/l 5 μg/l 5 μg/lChromium 50μg/l 50 μg/l 0.1 mg/L 50 μg/l (Cr6)Copper “ 2.0 mg/l TT 1 mg/lCyanide “ 50 μg/l 0.2 mg/L 50 μg/lFluoride 1.5 mg/l 1.5 mg/l 4 mg/l 1 mg/lLead “ 10 μg/l 15 μg/l 10 μg/lMercury 6 μg/l 1 μg/l 2 μg/l 0.05 μg/lNickel “ 20 μg/l “ “Nitrate 50 mg/l 50 mg/l 10 mg/L (as N) 10 mg/L (as N)Nitrite “ 0.50 mg/l 1 mg/L (as N) “Pesticides (individual) “ 0.10 μg/ l “ “

Pesticides — Total “ 0.50 μg/l “ “

Selenium 40 μg/l 10 μg/l 50 μg/l 10 μg/l

MEASUREMENT OF WATER POLLUTION.

Quantitative Water Quality Tests Fecal Coliform/Coliform

Biochemical Oxygen Demand(BOD)

Chemical Oxygen Demand(COD)

Temperature Turbidity/Total Suspended

Solids (TSS) Heavy metals, (e.g., lead,

mercury, cadmium) Carbon dioxide Nitrite Salinity Ammonia

Macro or micronutrients (e.g., K,S, Mo)

ChlorineIronSeleniumHardness

Sulfate and SulfiteMethane

Conductivity/Total DissolvedSolids (TDS)Alkalinity/Acid NeutralizingCapacity (ANC) Color OdorSynthetic organics (e.g.,pesticides, PCBs)

pH

Measures hydrogen ion concentration

Negative log of hydrogen ion concentration

Ranges from 0 to 14 std. units pH

7 neutral 0 - 7 acidic 7 - 14 alkaline

Thanks to Phil Brown

Solubility of Specific Ions Based on Water pH

Toxic metals less available in water at pH 6 to 8.

pH - Scientists measure pH to determine the concentration of hydrogen in the water. Most waters range from 6.5 to 8.5. Changes in pH can affect how chemicals dissolve in the water and whether organisms are affected by them. High acidity can be deadly to fish and other aquatic organisms. Low pH - corrosion, metallic tasteHigh pH – bitter/soda taste, depositsa decrease in pH (below 6) may increase the amount of mercury soluble in water. An increase in pH (above 8.5) enhances the conversion of nontoxic ammonia (ammonium ion) to a toxic form of ammonia (un-ionized ammonia).

CONDUCTIVITY

Measures electric conductivity (EC) of water

Higher value means water is a better electrical conductor

Increases when more salt (e.g., sodium chloride) is dissolved in water

Indirect measure of salinity Units are μmhos/cm at 25o

C or μSiemens/cm

Thanks to Phil Brown

SALINITY

Classification of Ground Water Composition Based on Total

Dissolved Solids Content Salts in Sea Water

Type of Water Dissolved salt content (mg/l)Fresh water < 1,000 mg/l

Brackish water 1,000 - 3,000 mg/l

Moderatly saline water

3,000 - 10,000 mg/l

Highly saline water 10,000 - 35,000 mg/l

Sea water > 35,000 mg/l

TURBIDITY Turbidity is a measure of the amount of total

suspended solid (TSS) particles in the water. Algae, suspended sediment, and organic matter particles can cloud the water making it more turbid.

Suspended particles diffuse sunlight and absorb heat. This can increase temperature and reduce light available for algal photosynthesis.

If the turbidity is caused by suspended sediment, it can be an indicator of erosion, either natural or man-made. Suspended sediments can clog the gills of fish. Once the sediment settles, it can foul gravel beds and smother fish eggs and benthic insects. The sediment can also carry pathogens, pollutants and nutrients

The units of turbidity from a calibrated nephelometer are called Nephelometric Turbidity Units (NTU).

TURBIDITY Measured in Nephelometric Turbidity Units (NTU) Estimates light scattering by suspended particles Photocell set at 90o to the direction of light beam to estimate scattered rather than absorbed light Good correlation with concentration of particles in water.

Thanks to Phil Brown

Temperature If the temperature gets too hot or too cold for some organisms, they die.

Temperature also can affect the chemistry of the water. For example, warm water holds less oxygen than cold water. A healthy cluster of trees and vegetation next to a stream or river helps keep temperatures cool for trout and other fish.

Temperatures can increase the solubility and thus toxicity of certain compounds. These elements include heavy metals such as cadmium, zinc and lead as well as compounds like ammonia .

Water temperature can not only increase the solubility of toxic compounds, but it can also influence an organism’s tolerance limit .

Mortality rates for zinc are significantly higher at temperatures above 25°C than at temperatures below 20°C . This occurs because tissue permeability, metabolic rate and oxygen consumption all increase with increased water temperature.

In one study on labeo bata fish, the 24 hour 50% lethal concentration (LC50) at 15°C was 540 mg/L, while at 30°C, the LC50 dropped to 210 mg/L .

Dissolved Oxygen Amount of gaseous oxygen

(O2) dissolved in water Oxygen gets into water by

diffusion from the surrounding air, by aeration, and through photosynthesis

DO range from 0-18 mg/l Need 5-6 mg/l to support a

diverse population DO < 2 mg/l – Hypoxia The Winkler test is used to

determine the concentration of dissolved oxygen in water samples

Thanks to Phil Brown

CBOD=Carbonaceous biochemical oxygen demand NBOD = Nitrogenous biochemical oxygen demand

Biochemical oxygen demand (BOD) Measures oxygen required for biological oxidation of

biodegrable compounds. BOD: oxygen uptake by microorganism during aerobic

growth in ww sample Standard BOD: 5 day incubation @ 20°C Samples require a series of dilutions to achieve suitable

oxygen consumption Pure water BOD = 1 ppm Polluted water BOD = 5 ppm or above

WHO Standard COD value=10mg/l

Differences between BOD and COD measurements.

Biological Oxygen Demand (BOD)

Chemical Oxygen Demand (COD)

Measure the amount of food (or organic carbons) that bacteria can oxidize.

Measures the content of all chemicals present in the water that are capable of being oxidized by the oxidizing agent.

Slow : five days required for BOD studies.

Faster : takes just two hours to complete.

Can only be use to test water from wastewater treatment plants that do not contain toxic industrial wastes.

*industrial wastewater that is rich in cyanides or heavy metal ions is toxic to the bacteria.

Can be use to test water from industrial and domestic waste water.

Toxicity Toxic Substances - Scientists also test for many harmful (toxic) things like metal, pesticides, and oil.

For example, scientists are finding mercury in certain types of fish, especially in lakes and estuaries. Mercury comes from mining, natural sources and air harmful substances are a problem in a stream, lake or bay.

Nutrients - The two major nutrients scientists measure are nitrogen and phosphorus. The presence of too many nutrients can hurt aquatic organisms by causing lots of algae to grow in the water. Nutrients can also affect pH, water clarity and temperature, and cause water to smell and look bad.

Algae blooms DO changes, fish kills Shift of trophic status toward eutrophication. Drinking water impairment (direct and indirect) Aesthetics (color, clarity, smell) Uptake and release of toxics

Fecal coliform and total coliform

Increased levels of fecal coliforms (fecal bacteria) provide a warning of failure in water treatment, a break in the integrity of the distribution system, or possible contamination with pathogens.

The assay is intended to be an indicator of fecal contamination, or more specifically E. coli which is an indicator microorganism for other pathogens that may be present in feces. EPA acceptable Levels is 0 colonies.

Total coliform bacteria, fecal coliform bacteria, and E. coli are all considered indicators of water contaminated with fecal matter. Contaminated water may contain other pathogens (micro-organisms that cause illness) that are more difficult to test for. Therefore these indicator bacteria are useful in giving us a measure of contamination levels

Indicator species Amphibians

Include frogs, toads,salamanders, newts, andgymnophiona, and are cold-blooded animals that

metamorphose from a juvenile,water-breathing form to anadult, air-breathing form.

Are indicator species ofecological conditions relatingto global warming, air

pollution chemicals, stormwaterrunoff, and newly extantdiseases (e.g. fungus).

Control of water pollution act

Safe Water Drinking Act 1974 Established maximum contaminate levels Regulated volatile organic compounds Required lead-free plumbing

Well-head protection

Clean water act 1972 Restore and maintain the chemical, physical, and biological

integrity of the nations water. provide enforcement mechanisms (e.g. civil actions/criminal

penalties) to ensure. Reduce polluted runoff from urban areas and animal feeding

operations.

Water Pollution Control Policy: Domestic Dimension [U.S.] Water Pollution Control Act, 1956

(i) Federal financial support for construction of waste treatment plants focused on a control strategy based on subsidizing construction of waste treatment

plants as a particular control activity. Municipalities would receive grant of upto 55% for construction of waste

treatment plants.

(ii) Enforcement conference mechanism

sought to effect direct federal regulation of waste discharges Federal authority could call for a conference of interstate water pollution problem.