Freshwater Pollution its Control Safe Drinking Water free

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Freshwater Pollution & its Control

Freshwater Pollution & its Control

Safe Drinking Water= free of diseasecausing organisms & toxic substances

Safe Drinking Water= free of diseasecausing organisms & toxic substances

World Commission on Water ½ of our world’s rivers are “seriously depleted & polluted,

World Commission on Water ½ of our world’s rivers are “seriously depleted & polluted, degrading & poisoning the surrounding ecosystems, threatening the health & livelihood of people who depend on them

Pollution • Can be physical, chemical or biological • Can affect water, air, soil

Pollution • Can be physical, chemical or biological • Can affect water, air, soil Freshwater Pollution: • Nutrient pollution • Biological pollution by disease-causing organisms • Toxic chemical pollution • Physical pollution by sediment • Thermal pollution

Source of Pollution Point Source • Distinct location • Particular factory pumping waste into

Source of Pollution Point Source • Distinct location • Particular factory pumping waste into a nearby stream • Sewage treatment plant discharging wastewater from a pipe into ocean Nonpoint Source • Multiple cumulative inputs over large areas • Entire farming region • Suburban community with many laws & septic systems • Storm runoff from parking lots The distinction can help control pollutant inputs into waterways

Nutrient Pollution, N & P • In addition to wastewater, N & P are

Nutrient Pollution, N & P • In addition to wastewater, N & P are also products of decomposition, fertilizers and are found in soaps & detergents Eutrophication • Hypoxia: extremely low dissolved oxygen concentrations in a body of water • 1. Influx of nutrients • 2. Rapid growth of algae “algal bloom”, blocks light (plants die less photosynthesis less oxygen produced) • 3. Algae eventually dies • 4. Decomposers consume most of oxygen as feed on algae (high BOD) • 5. Larger organisms, like fish, die due to lack of oxygen

Dead zones: low DO

Dead zones: low DO

Pathogens & waterborne diseases • 1. Drinking water that is contaminated with waste from

Pathogens & waterborne diseases • 1. Drinking water that is contaminated with waste from inadequately treated wastewater or animal feedlots • Pathogens: viruses, protists, bacteria • Fecal coliform bacteria=lives in the intestinal tracts of people & other vertebrates; not pathogenic but serve as indicators of fecal contamination • Cholera, Giardiasis, Typhoid, Hepatitis A, Dysentery • Wastewater dumped into natural bodies of water undergoes decomposition by bacteria • Increases Biological Oxygen Demand (BOD) • BIOLOGICAL POLLUTION BY PATHOGENS CAUSES MORE HUMAN HEALTH PROBLEMS THAN ANY OTHER TYPE OF WATER POLLUTION

Pathogens & waterborne diseases • Most outbreaks occur in less developed countries where no

Pathogens & waterborne diseases • Most outbreaks occur in less developed countries where no sewer or sanitation facilities exist • How to reduce risks: • Treating sewage • Use chemicals to disinfect water • Hygienic measures • Standards: • Drinking water→ no coliforms allowed • Swimming pool→ no more than 200 coliforms/100 m. L→ closed if amount too great. Same for beaches, lakes & rivers

Indicator Species • Indicator species are an easy way to test whether water is

Indicator Species • Indicator species are an easy way to test whether water is polluted with harmful pathogens • Fecal coliform bacteria • Indicator species: E. Coli • Fecal coliform bacteria test • Water sample passed through filter • Filter disk placed on growth medium that supports coliform bacteria for 24 hours • Count number of colonies of coliform bacteria

Oxygen Sag • Illustrates changes that occur in a flowing system when oxygen demanding

Oxygen Sag • Illustrates changes that occur in a flowing system when oxygen demanding wastes are added • Area upstream of wastes→ good • Where wastes added→ Dissolved Oxygen drops due to increased Biological Oxygen Demand • As water flows→ system slowly recovers back to original state

As BOD increases, DO decreases • Biological Oxygen Demand (BOD) • Dissolved oxygen (DO)

As BOD increases, DO decreases • Biological Oxygen Demand (BOD) • Dissolved oxygen (DO) • A measure of the oxygen used by microorganisms to decompose organic waste • The amount of oxygen available for use in the water • If there is a large supply of organic waste, bacterial count will be high, resulting in a high BOD • As BOD increases, DO decreases because the oxygen that is available is being consumed by the bacteria

Lower BOD values= less polluted water

Lower BOD values= less polluted water

Pathogens & waterborne diseases • Disease: Schistosomiasis • A problem in Nile River/High Dam

Pathogens & waterborne diseases • Disease: Schistosomiasis • A problem in Nile River/High Dam • Cause: pathogen vector • Warm, stagnant water allows the Schistosoma parasite (worm) to exist • The infectious form of the parasite lives in certain types of freshwater snails & can emerge, contaminating water. • People can become infected when their skin comes in contact with contaminated freshwater. • Symptoms: • Initial invasion of the skin • Itching and a rash (swimmer's itch). In this condition, the schistosome is destroyed within the skin. • Can migrate through blood to Intestine & Bladder • Abdominal pain & diarrhea • Frequent urination, painful urination (dysuria), and blood in the urine (hematuria).

Toxic Chemicals: Synthetic Organic Compounds • Pesticides • Lethal to amphibians at low concentrations

Toxic Chemicals: Synthetic Organic Compounds • Pesticides • Lethal to amphibians at low concentrations • Gills burst & tadpoles suffocate • Pharmaceuticals & hormones • Drugs that mimic estrogen connected to male fish growing female eggs • PCBs • Used in manufacturing of plastics & insulation of electrical transformers • Now banned • Carcinogen • PBDEs • Flame retardants • Found in aquatic birds, fish & breast milk • Exposure to some types lead to brain damage

Heavy metals • Lead • Contaminates water when it passes through pipes of older

Heavy metals • Lead • Contaminates water when it passes through pipes of older homes • Fetuses & infants most sensitive • Damage brain, nervous system, kidneys

Heavy metals • Arsenic • Occurs naturally in Earth’s crust but increased by human

Heavy metals • Arsenic • Occurs naturally in Earth’s crust but increased by human activity • Mining breaks up rock deep underground • Industrial uses for arsenic like wood preservatives • Can be removed from water via fine membrane filtration, distillation & reverse osmosis • Cancer of the lungs, skin, kidneys & bladder • Takes 10 or more years to develop after exposure • 1942 -1999 acceptable level 50 ug/L • 1999 acceptable level 10 ug/L

Heavy metals • Mercury • Occurs naturally in Earth’s crust but increased by human

Heavy metals • Mercury • Occurs naturally in Earth’s crust but increased by human activity • 2/3 burning of fossil fuels (coal) • Incineration of garbage, hazardous waste, medical & dental supplies • Raw materials that go in to manufacturing cement • Exploration of petroleum • Each petroleum well produces 180, 000 gallons of contaminated wastewater & mud • Water usually dumped at drilling site • Enter nearby waterways or infiltrate soil & pollute groundwater

Heavy metals • Mercury • Inorganic mercury not harmful but once mercury finds its

Heavy metals • Mercury • Inorganic mercury not harmful but once mercury finds its way into water bacteria converts it into methylmercury • Methylmercury damages nervous system, particularly in young children & developing embryos. Causes impairment of coordination & affects the senses of touch, taste, & sight • Human exposure mostly due to eating fish & shellfish bioaccumulates up food chain. • Tuna top predator • Common source of bioaccumulated mercury

Heavy metals • Acid deposition “Acid rain” • Source of lower p. H in

Heavy metals • Acid deposition “Acid rain” • Source of lower p. H in water due to smokestacks of industrial plants that were burning coal & releasing SO 2 & NO 2 • Chemicals in atmosphere converted to sulfuric & nitric acid • Acids return to earth as acid deposition (acid rain) • Causes p. H of water bodies to go below 5 • Toxic to many aquatic organisms • Coal scrubbers • Passes hot gas through limestone, which reacts with the acidic gas, removing the S & N from the hot gases that leave the smokestack

Heavy metals • Acid mine drainage • Causes low p. H in bodies of

Heavy metals • Acid mine drainage • Causes low p. H in bodies of water • Abandoned underground mines become flooded, which allows a rock called pyrite to break down & produce iron & hydrogen ions. • Produces acidic water with a low p. H • Occurs w/mountaintop removal when tailings dumped into stream beds • Can produce water that is close to a p. H of 0 • Trying to hold mining companies responsible • Passing stream water through limestone treatment facilities

Solid waste- Garbage • Medical waste • Threat to people (beach) • Coal ash

Solid waste- Garbage • Medical waste • Threat to people (beach) • Coal ash • Contains mercury, arsenic, lead • Not considered hazardous waste • Most states have either no regulation or weak regulations governing this waste

Sediment #1 Water Pollutant • Some bodies of water are naturally sediment rich, but

Sediment #1 Water Pollutant • Some bodies of water are naturally sediment rich, but most are not • An increase in sediment in a body of water can cause the habitat to dramatically change- no longer have a clearwater environment- less light coming through • • The higher the “turbidity”, the higher the cloudiness of the water Raises temperature of water Less light affects photosynthesis (less producers) less O 2 Clogs fish gills less O 2 • Cause: mining, clear-cutting, land clearing for housing development & careless cultivation of farm fields expose soil to wind & water erosion • Removing vegetation increases erosion

Thermal Pollution • Increasing the water temperature decreases the amount of dissolved oxygen •

Thermal Pollution • Increasing the water temperature decreases the amount of dissolved oxygen • When human activities raise water temperatures, some aquatic organisms may not survive • Electric & Nuclear power plants, Industrial plants • Water removed & used for cooling & then later discharged back into the river, but at a higher temperature • Thermal shock= dramatic change in temperature can kill many species • High temperature causes them to increase respiration, but there’s less O 2 in water • The solution: Cooling towers & holding tanks- water held in tanks until they cool down, then released into body of water.

Noise pollution • Noise from ships/submarines can interfere with animal communication • Loud sonar

Noise pollution • Noise from ships/submarines can interfere with animal communication • Loud sonar negatively affecting whales that rely on lowfrequency, long-distance communication • Beached whales been connected to use of military sonar & loud, underwater air guns • US Navy requested to install network of long-range sonar systems across ocean floor to detect incoming submarines • Rejected by federal judge due to impacts on endangered whales • Supreme Court ruled the President of the US could exempt the navy from environmental laws that related to sonar effects on ocean life

Clean Water Act, 1972 • All US waters “swimmable & fishable” • DOES NOT

Clean Water Act, 1972 • All US waters “swimmable & fishable” • DOES NOT PROTECT GROUNDWATER • Regulates the discharge of wastes, especially from industry, into rivers & streams (Monitors point sources) • Protects wildlife & established a system for granting permits for the discharge of pollutants • Sets standards for industrial wastewater, contaminant levels in surface water & funded construction for sewage treatment plants • Nonpoint sources are harder to regulate & therefore have a greater impact on water quality in the US • Govt. limits development on watershed land surrounding reservoirs

 • Safe Drinking Water Act • Sets nat’l standards for drinking water •

• Safe Drinking Water Act • Sets nat’l standards for drinking water • EPA responsible for establishing maximum contaminant levels for over 80 different substances/chemicals in surface & groundwater • Federal Water Pollution Control Act, 1948 • Establish controls for each major pollutant • Provide billions of dollars for sewage treatment plants • Great Lakes Water Quality Act, 1972 • Canada & U. S. • Huge strides in cleaning up area • London Dumping Convention, 1990 • Regulations for dumping industrial wastes, effluent, and plastics in ocean by 1995. Results still remain to be seen • Superfund Act • Provides funding for cleanup of contaminated abandoned sites that may be affecting water quality

Contaminant category Contaminant Microorganism Inorganic chemical Organic chemical Giardia Fecal Coliform Arsenic Maximum contaminant

Contaminant category Contaminant Microorganism Inorganic chemical Organic chemical Giardia Fecal Coliform Arsenic Maximum contaminant level (ppb) 0 0 10 Mercury 2 Benzene 5 Atrazine 3

Potable water = Drinking Water • “Safe Drinking Water Act”: The EPA sets standards

Potable water = Drinking Water • “Safe Drinking Water Act”: The EPA sets standards for over 80 drinking water contaminants • Before it’s sent to your tap, water from a reservoir or aquifer is treated … • 1. To clarify water →add coagulants → chemicals that will coagulate dirt & other particles by causing them to stick together & sink • 2. Water passed through filter → removes disease-causing agents • 3. Disinfected →using UV light, ozone or chlorine • 4. Many areas add fluoride to increase dental health (4 mg/L) • Best drinking water • Des Moines, Iowa; Austin, Texas; and Sioux Falls, S. D. • Worst drinking water • Pensacola, FL; Riverside, CA; Las Vegas, NV

Purification of Drinking Water • The Chlorine Dilemma • Chlorine is added to drinking

Purification of Drinking Water • The Chlorine Dilemma • Chlorine is added to drinking water to kill pathogens • Chlorine has recently been linked to several types of cancers (rectal and bladder) • Add chemicals to water to remove chlorine after use

Water Quality Testing • Biological properties Intolerant to stress Tolerant to stress Mayflies Pouch

Water Quality Testing • Biological properties Intolerant to stress Tolerant to stress Mayflies Pouch snails Caddisflies Tubifex worms Stoneflies Leeches • Presence of fecal coliform & disease-causing organisms • Algae & aquatic invertebrates are biological indicators • Chemical properties • Nutrient concentrations (P & N), p. H, taste & odor, hardness, dissolved O 2 • Hardness • High concentrations of Ca & Mg • Prevents soap from lathering, leaves chalky deposits when heated • Dissolved oxygen • Indicator of an aquatic ecosystems health • Surface waters low in DO are less capable of supporting aquatic life

Chemical Testing- p. H 4. 0 4. 5 5. 0 Noted Effects No fish

Chemical Testing- p. H 4. 0 4. 5 5. 0 Noted Effects No fish below this point Lower limit for most fish, amphibians & insects Decomposition processes inhibited, organic debris accumulates 6. 0 - 7. 5 8. 5 9. 0 Optimal range for most fish eggs & larvae Upper limit for most algae Upper limit for most fish

Chemical Testing- alkalinity • Not to be confused with p. H • A measure

Chemical Testing- alkalinity • Not to be confused with p. H • A measure of the buffering capacity– the degree to which water can resist changes in p. H • This capacity is determined by the amount of carbonate (CO 32 -) & bicarbonate (HCO 3 -) ions in the water • These ions react with, or buffer, incoming hydrogen (H+) ions that would otherwise lower the p. H • Natural source of carbonate: Limestone

Water Quality Testing • Physical properties • Turbidity= measures the density of suspended particles

Water Quality Testing • Physical properties • Turbidity= measures the density of suspended particles (sediment) • Turbid water= carries a lot of sediment; muddy-looking • Test: Secchi Disk • Color • Some forest streams are colored due to tannins in decomposing leaf litter • Temperature • High temperatures can interfere w/biological processes • Warmer water holds less dissolved oxygen

Secchi Disk

Secchi Disk

Groundwater Pollution • Toxins that occur naturally in groundwater that are toxic at high

Groundwater Pollution • Toxins that occur naturally in groundwater that are toxic at high concentrations • Aluminum, fluoride, nitrates, sulfates • Nitrates in drinking water cancer, miscarriages • Arsenic Bangladesh natural occurrence • Industrial, agricultural, urban wastes leaching into aquifers • Leakage from underground septic tanks • Contaminated sites near groundwater or surface water are high on the Superfund list