Water TestingWater Testing

ByBy

Lin WozniewskiLin Wozniewski

(lwoz@iun.edu) (lwoz@iun.edu)

How Do You Tell If There How Do You Tell If There May Be a Problem May Be a Problem

Somewhere & the Water Somewhere & the Water Should be Tested?Should be Tested?

• High population density next to High population density next to waterwater

• High industrialization next to waterHigh industrialization next to water• Agriculture next to waterAgriculture next to water• ““Straightened” river or artificial Straightened” river or artificial

lake shoreslake shores• Garbage along/in waterGarbage along/in water• Shallow water bottomShallow water bottom

How Do You Tell If There How Do You Tell If There May Be a Problem May Be a Problem

Somewhere?Somewhere?• No Fish/Dead FishNo Fish/Dead Fish

• People complaining of headaches etc.People complaining of headaches etc.

• Readings on key indicators Readings on key indicators higher/lower than normalhigher/lower than normal

• Large changes in readings from one Large changes in readings from one area to anotherarea to another

• ““Normal” readings where you would Normal” readings where you would not expect them – need to look @ not expect them – need to look @ unexpected chemistryunexpected chemistry

• New populations of speciesNew populations of species

Pollution or Contamination?• It is a pollutant if it is supposed to be

there, but the substance is present in higher quantity than it should be.– Fertilizers, some ions, etc.– Sometimes metals are thought of as

contaminants, but many soils contain arsenic and mercury naturally

• It is a contaminant if it is not supposed to be there at all– Plastics

Possible Types of Possible Types of PollutionPollution

ORGANICORGANIC• decomposition of once-decomposition of once-

living materialliving material• human & animal waste, algaehuman & animal waste, algae

INORGANICINORGANIC• suspended & dissolved suspended & dissolved

solids solids • silt, salt, mineralssilt, salt, minerals

TOXICTOXIC• heavy metals and lethal heavy metals and lethal

organic compoundsorganic compounds• iron, mercury, PCBsiron, mercury, PCBs

THERMALTHERMAL• water heated by urban water heated by urban

runoff or industryrunoff or industry• streets, nuclear powerstreets, nuclear power

BIOLOGICAL• introduction of non-native species (zebra mussels)

How Do We Test for These How Do We Test for These Types of Pollution?Types of Pollution?

• DO (Dissolved Oxygen)DO (Dissolved Oxygen)

• BODBOD55 (5 Day Biological Oxygen Demand) (5 Day Biological Oxygen Demand)

• pH (Test for acidity)pH (Test for acidity)

• Conductivity (TDS- Total Dissolved Solids)Conductivity (TDS- Total Dissolved Solids)

• Turbidity (How Clear is the Water)Turbidity (How Clear is the Water)

• Temperature (Thermal Pollution)Temperature (Thermal Pollution)

• Colorimetry (Test for metals)Colorimetry (Test for metals)

• Coliform (Test for Organic Pollution)Coliform (Test for Organic Pollution)

• Ion tests (Chlorine, phosphate, nitrogen, Ion tests (Chlorine, phosphate, nitrogen, etcetc

• Chlorophyl Chlorophyl

Dissolved OxygenDissolved Oxygen• Measures how much oxygen is Measures how much oxygen is

dissolved in the water and available dissolved in the water and available for plants and animals to breathfor plants and animals to breath

• SourcesSources– Dissolved airDissolved air– PhotosynthesisPhotosynthesis

• Measured with a probeMeasured with a probe• Best if done in the water body – can Best if done in the water body – can

be done up to two hours laterbe done up to two hours later• Because of temperature Because of temperature

dependence, it is measured in % dependence, it is measured in % SaturationSaturation

Amount of Dissolved Oxygen (mg/L) your Amount of Dissolved Oxygen (mg/L) your water sample would need to be 100% water sample would need to be 100% Saturated at the given temperature.*Saturated at the given temperature.*

Temp oCDissolved Oxygen (mg/L) Temp oC

Dissolved Oxygen (mg/L)

0 14.6 15 10.11 14.2 16 9.92 13.8 17 9.73 13.5 18 9.64 13.1 19 9.35 12.8 20 9.16 12.5 21 8.97 12.1 22 8.78 11.8 23 8.69 11.6 24 8.410 11.3 25 8.311 11.0 26 8.112 10.8 27 8.013 10.5 28 7.814 10.3 29 7.7

* @ Sea Level

Calculate % Saturation:Calculate % Saturation:

__DO mg/L____DO mg/L__ (your sample)(your sample)

Max DO mg/LMax DO mg/L (from chart determined (from chart determined by water temp) by water temp)

X 100%X 100%

Example at 19º C:

8.08.0 x 100% = 84.6% x 100% = 84.6% 9.45 9.45

State Standard > 5 mg/L, not < 4 State Standard > 5 mg/L, not < 4 mg/Lmg/L

Using the DO ProbeUsing the DO Probe

• The probe has to be filled with The probe has to be filled with solutionsolution

• The probe has to be warmed up The probe has to be warmed up for 10 minutes before use.for 10 minutes before use.

• The TI has an internal calibration The TI has an internal calibration curve. You can use it, or do a curve. You can use it, or do a calibration set yourselfcalibration set yourself

BOD 5 dayBOD 5 day• Measures how much of the dissolved Measures how much of the dissolved

oxygen is used up during the course oxygen is used up during the course of 5 daysof 5 days

• DO measures are taken at the same DO measures are taken at the same time as collection every day for 5 time as collection every day for 5 daysdays

• Tells about how much of the oxygen Tells about how much of the oxygen dissolved in the water is being used dissolved in the water is being used up by microorganisms & hence how up by microorganisms & hence how much is available to fish.much is available to fish.

• Is confounded by COD (Chemical Is confounded by COD (Chemical Oxygen Demand)Oxygen Demand)

• Measured on water taken back to labMeasured on water taken back to lab

BODBOD55

• DODO(Original sample)(Original sample) – DO – DO(Day 5)(Day 5) = BOD = BOD55

Typical range for BODTypical range for BOD55 = 0 to 6.3 = 0 to 6.3 mg/Lmg/LIndiana Average = 1.5 mg/LIndiana Average = 1.5 mg/L

pHpH• Measure of how acidic or basic the water Measure of how acidic or basic the water

isis• From 0 (very acidic) to 14 (very basic)From 0 (very acidic) to 14 (very basic)

• Influenced by geology, rain, and Influenced by geology, rain, and discharge from point sourcesdischarge from point sources

• Affects toxicity of other chemicals; many Affects toxicity of other chemicals; many aquatic organisms are very pH-sensitiveaquatic organisms are very pH-sensitive

• Changes with temperature, in response Changes with temperature, in response to high levels of photosynthesis; related to high levels of photosynthesis; related to alkalinityto alkalinity

• Typical range for pH = 7.2 to 8.8Typical range for pH = 7.2 to 8.8• Indiana Average = 8.0Indiana Average = 8.0• State Standard = between 6 - 9State Standard = between 6 - 9• Due to the state’s limestone geology, Due to the state’s limestone geology,

Indiana surface waters will typically have Indiana surface waters will typically have a pH that is relatively basic (> 7).a pH that is relatively basic (> 7).

pHpH• Can be measured right in water bodyCan be measured right in water body• Is a measure of how much pollution: Is a measure of how much pollution:

Sulfur Oxides, Phosphate, Nitrogen Sulfur Oxides, Phosphate, Nitrogen Oxides, and Carbon Dioxide is Oxides, and Carbon Dioxide is dissolved in the lake since most of dissolved in the lake since most of these form weak acids in waterthese form weak acids in water

• Uses a sensitive glass electrode Uses a sensitive glass electrode that MUST be kept wet at all times.that MUST be kept wet at all times.

• Electrode MUST be taken out of the Electrode MUST be taken out of the buffer solution prior to being placed buffer solution prior to being placed in water to be measuredin water to be measured

• Should not need to calibrateShould not need to calibrate

AlkalinityAlkalinity• A measure of how much buffering A measure of how much buffering

capacity the body of water has.capacity the body of water has.• If acid is put in pure water, the pH If acid is put in pure water, the pH

will change a lot.will change a lot.• If acid is put into a buffer, the pH will If acid is put into a buffer, the pH will

change very little – at least until the change very little – at least until the buffering capacity is reached.buffering capacity is reached.

• Living systems have natural Living systems have natural buffering mechanisms which are buffering mechanisms which are added to the water.added to the water.

• Limestone also has an ability to add Limestone also has an ability to add buffering capacity.buffering capacity.

TDS (Total Dissolved TDS (Total Dissolved Solids)Solids)• A conductivity test is used as a A conductivity test is used as a

measure of TDS since most measure of TDS since most dissolved solids are ionicdissolved solids are ionic

• Used in connection with pH as a Used in connection with pH as a measure of the amount of measure of the amount of ammonia, phosphate, nitrate, etc. ammonia, phosphate, nitrate, etc. dissolved in the body of waterdissolved in the body of water

• Can be measured right in the body Can be measured right in the body of water.of water.

• Probe MUST be inserted into water Probe MUST be inserted into water far enough for water to cover hole far enough for water to cover hole in side of probein side of probe

Ideal Drinking water from reverse osmosis, distillation, deionization, microfiltration, etc..

0-50 PPM

Often considered acceptable range for carbon filtration, mountain springs or aquifers.

50-140 PPM

Average tap water.140-400 PPM

Hard water. 170 PPM or above

Less desirable200-300 PPM

Unpleasant levels from tap water, aquifers or mountain springs.

00-500 PPM

The EPA's maximum contamination level. 500 PPM

Total Dissolved Solids

TurbidityTurbidity• A measure of how clear the water isA measure of how clear the water is

• Fish can not survive if they can not see foodFish can not survive if they can not see food

• Sample is compared with a standard that Sample is compared with a standard that comes with the machinecomes with the machine

• Sample must be mixed but not shaken Sample must be mixed but not shaken (stirred, not shaken) because water bubbles (stirred, not shaken) because water bubbles will confound the testwill confound the test

• Is a measure of how much material is Is a measure of how much material is suspended in the body of watersuspended in the body of water

• Typical range for TURBIDITY = 0 to 173 NTUTypical range for TURBIDITY = 0 to 173 NTU

• Indiana Average = 36 NTUIndiana Average = 36 NTU

TurbidityTurbidity

• NTU - Nephelometer Turbidity NTU - Nephelometer Turbidity Units: a unit of measurement Units: a unit of measurement commonly used in electronic commonly used in electronic turbidity meters that indicate turbidity meters that indicate how far light can penetrate into how far light can penetrate into a water sample before the a water sample before the cloudiness of the sample cuts cloudiness of the sample cuts into the light.into the light.

Secchi DiskSecchi Disk• A different way of measuring the turbidity A different way of measuring the turbidity

of the water.of the water.

• A disk with black and white areas is A disk with black and white areas is attached to a cord that has knots in it. attached to a cord that has knots in it.

• The disk is lowered slowly into the body of The disk is lowered slowly into the body of water until it disappears.water until it disappears.

• The point on the rope that just touches The point on the rope that just touches the water is notedthe water is noted

• The disk is pulled out and the depth at The disk is pulled out and the depth at which the disc disappeared is noted.which the disc disappeared is noted.

• Secchi Disks measure the water clarity at Secchi Disks measure the water clarity at many depths & can not be connected to many depths & can not be connected to turbidity directlyturbidity directly

TemperatureTemperature• Must be done in the body of waterMust be done in the body of water• What we are looking for is a What we are looking for is a

difference in temperature in the difference in temperature in the body of water that might indicate body of water that might indicate thermal pollutionthermal pollution

• Temperature of the water will Temperature of the water will determine how much oxygen can be determine how much oxygen can be dissolved into the waterdissolved into the water– The higher the temperature of the The higher the temperature of the

water, the less oxygen can be dissolved water, the less oxygen can be dissolved in the waterin the water

• State Water Quality Standard: < 5° State Water Quality Standard: < 5° F change downstream F change downstream (approximately 2.8° C)(approximately 2.8° C)

Oxygen & Temperature Graph

ColorimetryColorimetry

• Most heavy metals either have Most heavy metals either have colored ions, or can be reacted colored ions, or can be reacted with a reagent that will make the with a reagent that will make the ion colored that can be inserted ion colored that can be inserted in a colorimeter and the results in a colorimeter and the results compared using a calibration compared using a calibration curvecurve

Calibration CurvesCalibration Curves• The calculators display the output The calculators display the output

of the colorimeters in absorbance.of the colorimeters in absorbance.• These readings then have to be These readings then have to be

referenced to a standard.referenced to a standard.• To make the calibration curves, To make the calibration curves,

solutions of known amounts of solutions of known amounts of ions are tested and the ions are tested and the absorbance recorded.absorbance recorded.

• A graph is then made with the A graph is then made with the concentration of the ion being concentration of the ion being tested on the X axis and the tested on the X axis and the absorbance on the Yabsorbance on the Y

Calibration Curves Calibration Curves ContinuedContinued

• A best fit line is then put in.A best fit line is then put in.

• The absorbance of the sample is The absorbance of the sample is followed to the line and the followed to the line and the concentration is then read off concentration is then read off the corresponding X- axisthe corresponding X- axis

Calibration Curve Calibration Curve ExampleExample

Chromium Calibration Curvey = 9.3445x + 0.0446

R2 = 0.9976

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16

Concentration of Chromium (mg/l)

Ab

sorb

ance

Ion TestsIon Tests• These are done with probesThese are done with probes

• Some possible ion tests (there are Some possible ion tests (there are many others)many others)– Ammonium (NHAmmonium (NH44

++))

– Calcium (CaCalcium (Ca+2+2))– Chloride (ClChloride (Cl-1-1))

– Nitrates (NONitrates (NO33-1-1))

– Phosphorous (Usually POPhosphorous (Usually PO44-3-3))

• The output from the probe is recorded The output from the probe is recorded on the calculator as a millivolt reading.on the calculator as a millivolt reading.

• These also require a calibration curve These also require a calibration curve to interpret.to interpret.

PhosphatesPhosphates• Nutrient essential to plant growth, Nutrient essential to plant growth,

naturally present in low naturally present in low concentrationsconcentrations

• Enters water via runoff; present in Enters water via runoff; present in fertilizers, attached to soil fertilizers, attached to soil particles, and in organic wasteparticles, and in organic waste

• Can lead to eutrophication = Can lead to eutrophication = nutrient overload and the nutrient overload and the system’s response (lots of plant system’s response (lots of plant growth)growth)

• High P often results in low DOHigh P often results in low DO

Phosphate rangePhosphate range• Can be in the form of salts of phosphate Can be in the form of salts of phosphate

(Orthophosphate) or organophosphate(Orthophosphate) or organophosphate

• There are no state water quality There are no state water quality standards for Orthophosphate. However, standards for Orthophosphate. However, we do know the Total Phosphatewe do know the Total Phosphate

• Typical range (0 to 0.85 mg/L) andTypical range (0 to 0.85 mg/L) and

• Average (0.05 mg/L).Average (0.05 mg/L).

• We generally expect orthophosphate to We generally expect orthophosphate to be less than total phosphate, since be less than total phosphate, since orthophosphate is but one component of orthophosphate is but one component of total phosphate.total phosphate.

NitratesNitrates• Nutrients essential to plant Nutrients essential to plant

growthgrowth• Sewage is main source to rivers Sewage is main source to rivers

and streamsand streams• Excessive amounts contribute Excessive amounts contribute

to eutrophicationto eutrophication• High nitrate levels often High nitrate levels often

correspond to high total correspond to high total phosphates and low DOphosphates and low DO

• Typical range for NITRATE (NOTypical range for NITRATE (NO33--

11) = 0 to 36.08 mg/L) = 0 to 36.08 mg/L• Indiana Average = 12.32 mg/LIndiana Average = 12.32 mg/L

AmmoniumAmmonium• Ammonia is a gasAmmonia is a gas

• Ammonia reacts with water to form Ammonia reacts with water to form ammonium hydroxide – a weak baseammonium hydroxide – a weak base

• NHNH33 + H + H22O O NH NH44OHOH NH NH44++ + OH + OH--

• Ammonium is the only positively Ammonium is the only positively charged polyatomic ioncharged polyatomic ion

• Found in a lot of fertilizers as a Found in a lot of fertilizers as a source of nitrogen for plant growthsource of nitrogen for plant growth

• Generally measured with a probe Generally measured with a probe and then compared to a calibration and then compared to a calibration curvecurve

CalciumCalcium• Often leached out of limestone Often leached out of limestone

bedrockbedrock

• One of the major measures of One of the major measures of Hard WaterHard Water

• Measured with a probe and Measured with a probe and compared to a calibration curvecompared to a calibration curve

• Tends to be high in southern Tends to be high in southern Indiana & well water, but low in Indiana & well water, but low in Northern Indiana & surface Northern Indiana & surface waterwater

ChloridesChlorides

• Used as a measure of salinityUsed as a measure of salinity– Particularly in sea waterParticularly in sea water

• A measure of the amount of salts A measure of the amount of salts likely to be dissolved in the water.likely to be dissolved in the water.

• Most chlorides are solubleMost chlorides are soluble

• Measured with a probe and checked Measured with a probe and checked against a calibration curveagainst a calibration curve

How to Use Ion ProbesHow to Use Ion Probes• Probes are stored in long term bottles Probes are stored in long term bottles

with just Distilled Water in spongewith just Distilled Water in sponge• Probes need to be taken out and put Probes need to be taken out and put

in short term storage bottles with in short term storage bottles with High Standard ~ ¾ full @ least 30 High Standard ~ ¾ full @ least 30 minutes, but not > 24 hrsminutes, but not > 24 hrs

• Plug probe into TIPlug probe into TI• Turn on TITurn on TI• Push APPS buttonPush APPS button• Arrow down to DataMate (or push 4)Arrow down to DataMate (or push 4)• Push 1Push 1• Arrow down to Mode & push enterArrow down to Mode & push enter• Push 4Push 4

How to Use Ion Probes on How to Use Ion Probes on TITI• Arrow up to Channel 1Arrow up to Channel 1• Push 2 the Push 2 againPush 2 the Push 2 again• When voltage reading is stable press enterWhen voltage reading is stable press enter• Enter 100Enter 100• Clean off probe & dryClean off probe & dry• Put into low standardPut into low standard• When voltage reading is stable press enterWhen voltage reading is stable press enter• Enter 1 then Press 1 again & Press 1 againEnter 1 then Press 1 again & Press 1 again• Clean off probe & dryClean off probe & dry• Put into sample & press 2Put into sample & press 2• Clean & dry probeClean & dry probe• Read concentration in mg/100 ml directly-Read concentration in mg/100 ml directly-

calculator uses internal calibration curvecalculator uses internal calibration curve

ColiformColiform• Biological contamination can be found Biological contamination can be found

by using a substrate that will color by using a substrate that will color different colonies of bacteria differently. different colonies of bacteria differently.

• This allows the scientist to determine This allows the scientist to determine not only how large the bacteria count in not only how large the bacteria count in the body of water is, but also what the body of water is, but also what types of bacteria are presenttypes of bacteria are present

• These bacteria are not so much a These bacteria are not so much a problem by themselves, but indicate problem by themselves, but indicate that animal waste is being put into the that animal waste is being put into the water and the other parts of the waste water and the other parts of the waste are the contaminateare the contaminate

Coliscan EasygelColiscan Easygel

•Blue and purple Blue and purple colonies are colonies are E.coliE.coli•Pink colonies Pink colonies are coliformsare coliforms•Teal colonies Teal colonies are non-are non-coliformscoliforms•Best if Best if incubated at incubated at 3535ooC for 24 C for 24 hourshours

E. coliE. coli• Typical range for E. coli = 133 to Typical range for E. coli = 133 to

1,157 colonies/100 mL1,157 colonies/100 mL• Indiana Average = 645 Indiana Average = 645

colonies/100mLcolonies/100mL• State Water Quality Standard for State Water Quality Standard for

total body contact recreation:total body contact recreation:• <235 colonies/100 mL (single <235 colonies/100 mL (single

sample), andsample), and• < 125 colonies/100 mL < 125 colonies/100 mL

(Geometric mean of 5 samples (Geometric mean of 5 samples equally spaced over 30 days)equally spaced over 30 days)

Chlorophyll Chlorophyll

• This requires a sophisticated This requires a sophisticated spectrophotometerspectrophotometer

• This is one of the tests done on This is one of the tests done on water samples that are provided water samples that are provided to IU as part of the Clear Lakes to IU as part of the Clear Lakes programprogram

Interrelationships

Sources of PollutionSources of Pollution

• Point Sources Point Sources – Used to be largest souce of pollutionUsed to be largest souce of pollution– Most of these sources have already been Most of these sources have already been

cleaned upcleaned up– Individual factories, etc.Individual factories, etc.

• Non-Point SourcesNon-Point Sources– Now the largest source of pollutionNow the largest source of pollution– Grease, oil, gasoline dripping off vehiclesGrease, oil, gasoline dripping off vehicles– Salt put on roadsSalt put on roads– Run off from residential fertilizingRun off from residential fertilizing– Much more difficult to legislate clean upMuch more difficult to legislate clean up

Programs that empower Programs that empower studentsstudents• Hoosier River WatchHoosier River Watch

– http://www.in.gov/dnr/nrec/2945.htm– Requires teacher trainingRequires teacher training– Kits are available for checkout and use. Kits are available for checkout and use. – Students enter data directly into a database Students enter data directly into a database

& the data is used by real scientists& the data is used by real scientists

• Clean Lakes ProgramClean Lakes Program– http://www.indiana.edu/~clp/index.html– Run by IURun by IU– Kits are availableKits are available– Student collected data goes into real Student collected data goes into real

databasedatabase

• Other programs out there tooOther programs out there too

ResourcesResources

• For activities like the ones we are For activities like the ones we are handing out (grouped by grade and handing out (grouped by grade and subject):subject):– http://education.ti.com/educationportal/activity

exchange/activity_list.do?cid=us

• For information on water quality (and For information on water quality (and all kinds of other natural resource all kinds of other natural resource education questions):education questions):– http://www.in.gov/dnr/nrec/

ResourcesResources

• North American Association for North American Association for Environmental EducationEnvironmental Education– http://eelink.net/pages/Student%20Envir

onmental%20Education%20Sites