Water PollutionMichael, Teagan, Lara and

Deepak

Cuyahoga River Case

● 1969: Cuyahoga river in Ohio that started on fire because of industrial waste, tires, and oil in water.o Fires like this were not uncommon due to high levels of

pollution in rivers.o At least 13 fires were reported on Cuyahoga river.

● This issue brought national attention to the problem of water contamination and started a movement that led to the Clean Water Act.

Cuyahago River

Point and Nonpoint Sources

● Pollution is any physical, biological or chemical change in water quality that adversely affects living organisms or makes water unsuitable for use.

● Point Sources: Factories, power plants, sewage treatment plants, and underground coal mines that discharge pollution from specific locations such as drain pipes and ditches.

● Nonpoint Sources: Sources are scattered or diffuse, having no specific location where they discharge into water.o example: runoff from fields and feedlots

points sources are predictable whereas nonpoint sources are episodic.

the irregular timing of nonpoint sources makes them difficult to monitor and regulate.

Atmospheric Deposition

● Atmospheric Deposition is the accumulation of contaminants carried by air currents and precipitated into watersheds or directly onto surface waters such as rain and snow.

o Great Lakes: over time, the lakes accumulate industrial chemicals such as PCB’s, dioxins, and agricultural toxins.

o It is estimated that 600,000 kg of the herbicide Atrazine is contained within the Great Lakes.

o Lakes are pollution sources as well as recipients. example: 26,000 metric tons of PCB chemicals have disappeared

from Lake Superior. Chemicals evaporate from surface and are carried by air currents.

Water Pollution in MN

● Water is one of the most precious resources in Minnesota. Lakes are places of pristine beauty for many people and it is up to us to make sure it stays this way.

o Out of state mining companies are starting to experiment with sulfide mining outside of the Boundary Waters. Runoff from mining can pollute waters with sulfuric acid, mercury

and heavy metals.

● In 2013, high nitrate levels and unsafe drinking water were found in 27% of Minnesota’s streams and rivers.

● Industrial facilities dump over 1.4 million tons of toxic chemicals into rivers every year in MN.

● Over 70% of nitrogen pollution that gets into water comes from cropland.

The Threat of Infectious Agents

● Most serious pollutants are pathogenic organisms.

● Waterborne diseases include typhoid, cholera, bacterial and amoebic dysentery, polio and hepatitis.

● Main source of pathogens are from untreated or improperly treated human wastes. Animal wastes from feedlots or fields near waterways are sources of pollution.

o Water in Less-Developed and Developed Countries

o about 90% of people in developed countries have safe sewage disposal and 90% have clean drinking water.

o At least 2.5 billion people in less-developed countries lack sanitation and about half don’t have access to clean drinking water.

Water Quality Control

● Water Quality Control: Analyse water for presence of Coliform bacteria, types that live in colons or intestines of humans and animals.

o Most common: E Coli

● Use water sample containing a medium that supports bacterial growth. If any colonies are found in drinking water samples, the water is considered unsafe for drinking.

o Bacteria detected by measuring

oxygen levels. Oxygen in water good

indicator of water quality and life it will

support.

Ways to Detect Water Pollution

● Water with an oxygen content above 6 ppm will support aquatic life but water with less than 2 ppm oxygen will mainly support worms, fungi, bacteria and other decomposers.

o Organic waste is rich in nitrogen and phosphorus which stimulates growth of oxygen- demanding bacteria.

● A few useful tests to examine presence of organic waste in water.

o Biochemical oxygen demand (BOD)

o Chemical oxygen demand (COD)

o Dissolved oxygen content (DO)

● The effects of oxygen- demanding waste depends on volume, flow, aeration and temperature.

Biochemical Oxygen Demand

● Downstream from a point source, we can see a characteristic decline of oxygen and then a restoration of water quality.

● Upstream from a point source, oxygen levels support life.

● Below source of pollution, oxygen levels begin to fall as decomposers metabolize waste.

● The oxygen decline is called the oxygen sag.

● Rough fish such as carp can survive this environment because they eat decomposers and the waste.

● Further downstream, water can become so depleted, only microorganisms and invertebrates can survive=A Dead Zone

● Eventually, nutrients get used up, decomposers decrease and water becomes oxygenated again.

Biochemical Oxygen Demand

Eutrophication

● Eutrophication: An increase in nutrient levels and biological productivity.

o Water rich in organisms and organic materials is eutrophic.

o Clear water with low biological productivity is oligotrophic. rate of eutrophication depends on water chemistry, depth, volume

of inflow and mineral content.

● Cultural Eutrophication: Human caused increase in biological productivity.

o Nutrient enrichment sewage, fertilizer runoff and decomposing leaves from gutters can cause increase in biological productivity. Pros: Fish grow faster and larger. Cons: Elevated phosphorus and nitrogen levels stimulate “algae

blooms” Bacteria increase and decomposers deplete oxygen levels, causing other plants, algae and organisms to die.

Red Tides

● Bloom of deadly aquatic microorganisms.

● Nile River: possibly the 1st recorded “red tide” occurrence.

● Common in slow-moving rivers, brackish lagoons and estuaries.

Inorganic Pollutants

● Include metals, salts, acids and bases.

o Toxic chemicals released by rocks through weathering and are carried by runoff into lakes and rivers or percolate into groundwater aquifers.

● Heavy Metals: mercury, lead, tin and cadmium

● Super Toxic Chemicals: selenium and arsenic.

● Acids, Salts, nitrates and chlorine: not normally toxic at low concentrations but deadly if concentrated enough.

o Example: Mercury released from coal burning plants affects waters and wildlife. Top predators are especially likely to bioaccumulate toxic concentrations of mercury. Highly advised to avoid fish such as blue-fin tuna, king

mackerel,marlin and swordfish which contain mercury.

Organic Pollutants

● Include drugs, pesticides and other industrial substances.

● Runoff of pesticides from farm fields, forests and roadsides disrupt ecosystems and harm wildlife including nontarget organisms.

o example: DDT and Atrazine

● Other Toxins Include:

o unwanted food, medicines, supplements that get dumped down sinks or toilets.

o compounds of caffeine, antibiotics, birth- control hormones etc.. found downstream from major cities. One stream was tested for 95 contaminants including antibiotics,

hormones, detergents, plasticizers, insecticides. One stream contained 38 of the toxins tested.

Further Water Issues

● Sediment can degrade water quality.

● Fills lakes, obstructs channels.

● Affects drinking water

● Blocks sunlight

● However mud can nourish farm fields

● Thermal Pollution

● Affects water quality and aquatic life

● Affects species requiring lots of oxygen

● Alters vegetation cover and runoff

● Thermal Plume: heated water from an

● industrial facility enters rivers and

● disrupts ecosystems and organisms.

The Clean Water Act-1972● Regulates surface water waste

dumpso NPDES- National Pollution

Discharge Elimination System

● Upgraded and built sewage treatment plants

● Reestablished life in aquatic ecosystemso Lake Eyre

● Not all water bodies are monitoredo only “navigable” waterwayso Supreme court case 2006

● 21,000 bodies of water do not meet their designated uses

Watershed Level Monitoring● 1998- switch to watershed level monitoring● TMDL- Total Maximum Daily Load

o Amount of a particular pollutant a body of water can receive from both point and nonpoint sources.

● Cannon River Watershedo The Straight and Cannon riverso about 946,000 acreso Cannon River Watershed

Partnershiphttp://ofmpub.epa.gov/waters10/attains_waterbody.control?p_au_id=MN07040002-582&p_cycle=2010

Nonpoint Sources● Harder to identify and regulate● 75% of water pollution from soil erosion

o Fertilizero Feedlots o Petso Fossil Fuels

● Increased 4 fold since 1972

Water Quality Today● Japan, Australia, West Europe

o Equal to or surpassing the United States The Rhine Minamata Bay

● Russia, East and Central Europeo Cold War slowed environmentalism

● Chinao 70% water unsafe for consumption

● Indiao Coming into contact with surface water is considered bad for health

● South America, Africa Asiao 95% of sewage is untreated

Ground Water Pollution

95% of US drinking water comes from aquifers● MTBE- gas additive that decreases CO and hydrocarbon output of cars

o Present in 27% of US aquifers● Treatment expensive but possible● Northfield

o Jordan Aquifer

Jordan Aquifer

Ocean Pollution● Toxic Chemicals, Heavy Metals, Disease Causing Organisms, Sediment

o Coastal waters most affectedo Algal blooms

● Discarded Plastics and Littero Travels the Globeo 6 Millions tons added to the ocean every year

● Oilo seeking sources farther away and riskiero 3-6 Million tons spilled every year

half from water transportation

Water Pollution Control● Best method is avoidance

o Unleaded gasoline has caused a significant decrease in lead levels in surface water

o Studies show that reducing road salt by up to 90% has no significant effect on driving safety

o Recycling/reclaiming materials also decreases pollution

Nonpoint Pollution● Agriculture: 60% of all threatened surface water is affected by eroded fields

and overgrazed pastures

● Urban runoff: streets, industry, and yards feed into storm drains

● Construction sites: small area, but high quantities (10-20 times as much runoff as agriculture per area)

● Land disposal: landfill and septic tank leaks

● Soil and water conservation go hand in hand

● Chesapeake Bay used to have abundant sea life, degraded in the 1870s, became first estuary in America targeted for restoration

Human Waste● Degrades naturally in low quantities

o Impossible in cities

● Outhouses were developed for early sanitation

o Allowed groundwater contamination

● Septic tanks came next

● Chesapeake Bay watershed has 420,000

septic systems

● Maryland plans to spend $7.5 million annually on septic systems

Sewage● Three types of municipal treatment

● City treatment levels vary

● Northfield has a tertiary treatment facility

o Chemicals used to remove phosphorous

Primary Treatment● First step. Always used

● Physically separates large solids

● Many pathogens remain in effluent. It cannot be discharged into ground or surface water

Secondary Treatment● Biological Degradation. Three systems used interchangeably

1. Effluent spread on filter bed. Bacteria in filter bed aerobically decompose dissolved organic compounds

2. Effluent mixed with bacteria-rich slurry. Aerated to provide oxygen and encourage decomposition

3. Effluent collected in lagoons. Sunlight, algae, aquatic organisms, and air allow breakdown of of organic matter. Cheap and low energy

● Product treated with chlorine, UV light, or ozone to disinfect

● Heavy metals often remain after treatment

Tertiary Treatment● Removes plant nutrients (especially nitrogen and phosphate) from

secondary effluent. Prevents algal blooms and eutrophication

o Passage through wetland is effective

o Chemicals are also used to bind with nutrients

Stormwater● Stormwater is often fed into treatment plans because runoff has high

concentrations of chemicals and refuse from runoff

● Heavy rain overloads systems and causes stormwater and untreated sewage to overflow directly into receiving water

● Retroactive separation is environmentally disruptive and extremely expensive

o The stormwater is usually re-routed directly into a water source and pollutes it

Low-Cost Waste Treatment● Treatment methods of developed countries are often too expensive for

developing countries

● Effluent Sewerage: hybrid of septic and full sewer system

o Collection/digestion tank near every dwelling

o Effluents pumped to central treatment plant

o Tanks must be emptied yearly

o Facilities are smaller and cheaper

Wetland Treatment● Wetlands are FREAKING AWESOME

● Natural and artificial wetland effectively dispose of waste

● Constructed wetlands cut secondary treatment costs by ⅔

● Effluents irrigate crops and raise farmed fish

o 20-30 days is enough for safe water

● Wetlands can support human food supplies

o Estimates of up to 1.5 billion people

Water Remediation● Containing and treating contaminated water

● Containment: confine dirty water or divert ground and surface water

● Deep pollutants can sometimes be treated with injected chemicals

● Absorbent materials (straw) spread on spills

● Extraction: pump out contaminated water and use chemicals to treat it

Bioremediation● Using living organisms to clean contaminated water

o Cheap and effective

o provides wildlife habitat

● Duckweed: grows fast and removes nutrients

o Fast, cheap, effective

o Harvested for fuel, fertilizer, or feed

o Contains 2x the protein of alfalfa by mass

● Companies make compact and very efficient systems

Water Legislation

● Clean Water Act : The most effective of all environmental legislation in the U.S.○ Goal: To return all U.S surface waters to “fishable and

swimmable” conditions

International Water Quality legislation

Not everyone is happy with the Clean Water Act

● One of the controversial provisions of the act has been section 404, which regulates draining or filling of wetlands.Farmers, Land developers and others who are prevented from converting wetlands to other uses often are outraged by what they consider “taking” of private lands.

● “Unfunded Mandates”: Requirements for state and local governments to spend money that is not paid back by congress.

International Water Law

United Nations Convention on the Law of the Sea

(UNCLOS): Also called the Law of the Sea treaty defines the rights and responsibilities of nations with respect to their use of the world's oceans, establishing guidelines for businesses, the environment, and the management of marine natural resources. It was signed in 1982.

Apart from the Water Law: Goal 7, target 10 of the Millenium Development Goals aims at halving by 2015 the proportion of people without sustainable access to safe drinking water and basic sanitation.

At St.Olaf

● Regent Hall’s “green roof” water collection

● Student uses internship abroad to analyze international water issues

Personal steps to improve water quality

● Compost your yard waste and pet waste so that they do not mix with clean water resources.

● Do not fertilize your lawn or apply lawn chemicals.● Make sure your car doesn’t leak fluids, oil or solvents on streets

and parking lots, from which contaminants wash straight away to rivers and lakes.

● Don’t buy lawn mowers,personal watercraft, or other vehicles with two-cycle engines, which release abundant fuel and oil into air and water. Instead, buy more efficient four-stroke engines.

Personal Steps

● Create a “rain garden” to capture and filter surface runoff. it helps recharge groundwater aquifers and keeps nutrients and toxins out of rivers and lakes.

● Keep informed about water policy debates at local and federal levels. Policies change often and public input is important.

Proportion of Population receiving Clean Drinking Water in the World

Bringing Safe Water