Transcript Water Quality

Water Quality
In the News
• Official: Gas Spill Has Had No Impact on Water So Far October 22,
2016
• Drinking gasoline?
• St. Petersburg “Chameleon River” Turns Pale White October 19, 2016
• Milk and honey or pollution?
• White dust-like substance
• Russia Probes Why Siberian ‘River of Blood’ Is Running Red
September 8, 2016
• Possibly from a nearby nickel plant
• Company claimed “the color of water in the river is not different from
its regular state”
• US air force base leaks toxic chemicals into sewer
system October 19, 2016
• PFC’s
• Into creek or sewer plant?
In the News
• China pollution: Over 80% of rural water in
north-east 'undrinkable‘ April 12, 2016
• Rural versus Urban, Shallow versus Deep
Groundwater
• How Toxic Algae Bloom Became a Campaign
Issue for Clinton and Trump October 21,
2016
• Bacteria, not algae
• DNC Apologizes for Sewage Dump in
Gwinnett County October 18, 2016
• Georgia
• Sewage dumped into storm drain
• Septic Systems versus Combined Sewer
Systems?
In Pig News…
• Pig Blood in Trinity River, NBC
DFW, 2012
• Pig Blood Spill Was an
Accident, Dallas Morning
News, Jan 26, 2012
• State Environmental Agency
Voids Permit Application,
Dallas Morning News,
December 16, 2013
• Felony Counts Dropped, Dallas
Morning News, May 6, 2014
• The Man Who St opped the
Pig Blood, “D” Magazine, July
2014
What is the cause?
• Mutations more common
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over fishing?
Reduction in gene pool?
Pollution?
Infections?
• Two Headed Sharks Keep Popping up and No One Knows Why, National
Geographic, November 2, 2016
What is Water Quality?
• “a measure of the suitability of water for
a particular use based on selected
physical, chemical, and biological
characteristics.” – USGS Water Science
School
• Just streams/rivers?
• No. Can include ditches, natural and
man-made streams/rivers, ponds, lakes*,
bays, oceans
*that connect with state/federal waterways
• WOTUS Controversy
• Waters of the State [of Texas TWC 11.021]
Water Quality vs
Water Pollution
• Can be the same thing
• However, water quality
can indicate “good” as
well as bad
• Water pollution
typically infers a
negative quality versus
lack-of pollution
Why is it important?
• Water is life
• Supports living things
• Flows downhill
• connects to others waterways or water
bodies
• Food chain
• poor quality for basic aquatic lifeforms will
lead to poor quality of higher lifeforms
(bioaccumulation)
Water Quality Differences
Around the World
• Technology
• Knowledge/Science
• Government Power/Compassion
• Economics (part of a later unit)
• Companies
• Population
• Government
“Drinking” Water
• The Safe Drinking Water Act (SDWA),
1974, was implemented to protect
public drinking water supplied
throughout the country
• EPA sets standards for drinking water
quality and safety
What is a “public water supply (or system)”?
• A water system that provides water for human consumption to at least 15
service connections OR serves an average of at least 25 people for at least 60
days per year
• “Public” water system can be publically (i.e. municipality) or privately owned
• Approximately 155,000 public water systems in the US
• Provide drinking water to 90% of the US population
Types of Public Water Systems
• Three main types:
• Community Water System (CWS)
• A public water system that supplies water to the same population year-round.
• Non-Transient Non-Community Water System (NTNCWS)
• A public water system that regularly supplies water to at least 25 of the same people at
least six months per year. Some examples are schools, factories, office buildings, and
hospitals which have their own water systems.
• Transient Non-Community Water System (TNCWS)
• A public water system that provides water in a place such as a gas station or campground
where people do not remain for long periods of time.
Water Treatment Plant (video)
Bottled versus Tap Water
A different issue…
Which is better?
• Bottled water is regulated by Food and Drug Administration
• Tap water is regulated by the Environmental Protection Agency (EPA)
or its delegated authorities (i.e. TCEQ in Texas)
• “Texas requires water haulers transporting water in a tank truck or trailer to
maintain a minimum chlorine residual of 0.5 mg/L in the water, whereas FDA
does not have any specific regulations requiring chlorination of water.”
• Inspection/Oversight
• Possibly both FDA and EPA/TCEQ
• Sampling
• Production
• reverse osmosis, distillation, micro-filtration, carbon filtration, ozonation, and
ultraviolet (UV) light
Bottled water is often nothing more than
filtered tap water
• Problems with bottled water
Quick Check – National Drinking Water Database
• 90210 – Beverly Hills, CA
• 20500 – The White House, Washington, D.C.
• 80901 – Colorado Springs, CO
• 76208 – Denton, TX
• 76384 – Vernon, TX
• 48501 – Flint, MI
Tap Water Concerns
• Bacteria and Parasites - respiratory distress, vomiting and diarrhea
• Heavy Metals - can affect brain development in fetuses and small
children
• Nitrates – blue baby syndrome due to shortness of breath upon
exposure above the MCL
Where Tap Water is Safe
“Improved” Water Around the World
Wastewater
• Domestic, Industrial, and Commercial
discharges, either piped, hauled, or
otherwise disposed
• Typically sent via pipe to a Wastewater
Treatment Facility where it is treated and
disposed, held in a storage tank/vessel
where it is hauled to a treatment facility, or
treated at the generating facility and
disposed directly to a water body or
reused for a beneficial purpose
Denton’s Dirty Jobs – Wastewater Treatment
• Pecan Creek WWTP (You Tube)
Pecan Creek Wastewater Discharge Permit (TPDES)
WQ0010027-003 – City of
Denton Pecan Creek WWTP
TPDES Permit
In the News
• Boil Water Advisory Notice Issued in Troy, Michigan, 11-13-2016
• 70 Car Sized Stingrays Die Mysteriously, 11-10-2016
• Dirty Danube: looming pollution threats to the world’s most
international river, 11-13-2016
Discussion
• Clean water from air?
• http://www.popsci.com/this-machine-turns-sunshine-and-air-into-cleanwater
TPDES
Permit
• CBOD(5)
• Total
Suspended
Solids
• Ammonia
Nitrogen
• (T) Phosphorus
• (T) Nitrogen
• (T) Kjeldahl
Nitrogen
• NitriteNitrogen
• NitrateNitrogen
• OrthoPhosphate
• E. Coli
• pH
• visible oil
• dissolved
oxygen
Monitoring Parameters
• CBOD(5) – A type of BOD which is a 5-day test that measures oxygen used by bacteria during the
oxidation of organic matter. For the CBOD test, an inhibitor is utilized to prevent measuring the
amount of oxygen used to oxidize certain forms of nitrogen. This test is required when separate
measurement of Ammonia Nitrogen is also required since that will measure the amount of oxygen
used during oxidation of reduced nitrogen. It is an important since it measures how much oxygen could
be required and therefore depleted from the receiving water due to remaining organic materials.
• Total Suspended Solids – A measurement of the amount of solids retained in a filter. This is to be
distinguished from total dissolved solids which is the amount of solids that pass through a filter. Some
problems faced in aquatic environments when there are high TSS includes reduced sunlight passing
through the water (less photosynthesis and therefore oxygen conversion), an increase in water
temperature since particles will absorb heat (which will then not hold as much oxygen), and solids can
interfere with fish functions (breathing, growth rates, reproduction, etc.)
• Ammonia Nitrogen (NH3-N) – A measure of the amount of ammonia Levels are dependent on pH and
temperature. Ammonia is produced from decaying organic material and in human and animal waste.
Bacteria may oxidize ammonia into nitrate or nitrite. High levels can affect hatching and growth rates
in fish. Fish gills, liver, and kidneys may also be negatively affected. In humans, high levels can cause
loss of equilibrium, convulsions, coma, and death.
Monitoring Parameters (continued)
• Total Phosphorus – A measure of both the dissolved and insoluble phosphate. Non-point sources of
phosphates include natural decomposition of rocks and minerals, stormwater runoff, agricultural
runoff (fertilizers), erosion and sedimentation, atmospheric deposition, and direct input by
animals/wildlife (organic wastes, detergents). Point sources may include wastewater treatment plants
and permitted industrial discharges. Although it is an essential nutrient, too much can lead to
excessive algae growth which creates oxygen through photosynthesis but uses oxygen at night
(respiration) as well as when they die (which occurs when there are no longer enough nutrients for the
algae) and lowers pH due to creation of carbonic acid when the carbon dioxide reacts with water
(Calvin Cycle). Source: Water Research Center
• Total Nitrogen – Sources of nitrogen include WWTPs, fertilizers, and animal manure. Essential
nutrient but excess amount can lead to low oxygen levels.
• Total Kjeldahl Nitrogen – One of three components of total nitrogen (the others being nitrate and
nitrite). The total concentration of organic nitrogen and ammonia. Measures the amount of reactive
nitrogen that can be used by autotrophic bacteria which requires (depletes) oxygen.
• Nitrite-Nitrogen – One of the three components of Total Nitrogen. Not only is nitrite highly toxic to
fish and humans, it can consume chlorine therefore reducing disinfection in plants utilizing chlorine gas
or hypochlorite (or requiring more to be used to get the same effect as effluent with low nitrite).
Monitoring Parameters (continued)
• Nitrate-Nitrogen – One of three components of Total Nitrogen. Sources include fertilizers and
decomposition of human and animal wastes. Can lead to excess algae and subsequently a depletion
of oxygen.
• Ortho-Phosphate – One of three forms of phosphates (the others being metaphosphate and organically
bound phosphate) which typically occur in living and decaying plant and animal remains, bonded to
sediment/soil, or as a mineral of rocks/sediment/soil. Orthophosphate primarily comes from partially
treated or untreated wastewater, runoff from agricultural sites or lawns (most fertilizers are rich in
phosphates). Phosphates are not toxic to animals or people unless at very high levels. However,
although phosphorus is an essential nutrient needed by all living things, excess amounts can results in
eutrophication (negative environmental response to nutrients causing a decrease in oxygen and
otherwise decrease in biodiversity and possible increase of consuming bacteria).
• Escherichia coli – A type of fecal coliform bacteria, E. coli live in the intestines of warm blooded animals
(i.e. humans). The presence of E. coli in an aquatic environment is an indication of recent (+/-3 days)
sewage or animal waste contamination either directly or indirectly. In 2009, most states changed the
monitoring requirements to E. coli as a replacement for fecal coliform, since E. coli has been shown to
be a better predictor of the potential for impacts to human health from exposure to wastewater
effluent and surface waters which contain wastewater effluent
Monitoring Parameters (continued)
• pH – A direct determinant of solubility and biological availability of chemical constituents such as
nutrients and heavy metals. This means that even if there is a large amount of phosphorus, the
pH will determine how much will be available to aquatic life. Also, pH will determine the level of
toxicity of heavy metals by how soluble they are. Typically, the lower the pH, the more soluble
the metals are and therefore, the more toxic. Source: USGS definition and examples
• Visible oil – Produced either by natural seeping (where there are oil and gas deposits) or
anthropogenic sources. Oil (and gas) at the water surface prevent atmospheric oxygen from
entering the water body which would otherwise occur naturally. Once all the dissolved oxygen in
the water beneath the oil layer is consumed, replenishment by atmospheric oxygen will be
significantly limited. Luckily, most petroleum products will naturally disperse with heat and
sunlight. See physical chemistry article for oils affect on water.
• Dissolved oxygen – An essential element for living things. Highly dependent on organic matter
(which consumes oxygen in the water) and temperature (higher temperature will not hold as
much oxygen as cold water).
Typical forms of disinfection
• Chorine (gas, liquid – sodium hypochlorite)
• Can form trihalomethanes (THMs) which can include chloroform, bromine dichloromethane, chlorine dibromomethane, and
tribromomethane
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Not from combination of chlorine and methane but rather chlorine and organic material
Form more frequently with higher pH values
• Can form Halogenic acetic acids (HAAs) which are related to THMs.
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Also form when chlorine is combined with organic material
Form more frequently with lower pH values
• Chloramine (chlorine + ammonia)
• More stable and slower to dissipate than chlorine
• Although lower than chlorine, chloramines still have a tendency to create chlorocarbons (i.e. chloroform) which have been identified
by EPA as carcinogenic since 1979.
• An increase in chloramines is also suspected to allow an increase of lead exposure
• Chloramines can be removed from water by UV light
• UV light
• Although referred to a UV disinfection, UV irradiation inactivates microorganisms by disrupting their DNA or otherwise sterilizing
them to prevent reproduction
• UV light as a form of treatment can be limited in effectiveness by light intensity/transmissivity and the presence of organic material in
the water
• Ozone
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Highly effective in eliminating (disinfecting) bacteria and viruses and inorganics such as pesticides.
Can still form disinfectant byproducts such as THMs
Dissipates readily and so is not suitable to maintain a disinfectant residual throughout a water distribution system
Also highly effective in odor and taste elimination
Less typical forms of disinfection
• Chlorine dioxide
• Does not form toxic byproducts
• More effective in disinfecting viruses at low doses than chlorine
• Hydrogen peroxide (H2O2)
• Considered a weak microbiocide when compared with chlorine, ozone, and other
common disinfectants
• Not currently approved as a stand-alone method of disinfection
• Effective in reducing Taste and odor, hydrogen sulfide, iron, and the formation of
THMs, TTHMs, and HAAs
• Expensive
• Peracetic acid
• Combination of acetic acid and H2O2
• pH <2 and so requires pH adjustment prior to discharge