I. I.Water Pollution – Sources and Effects B. B.Sources 1. 1.Pollution a. a.Point sources Discharge directly into receiving waters Easier to characterize and regulate than NPS’s b. b.Non-point sources Pollutants from diffuse sources May vary regionally and seasonally Ex – Chloride from salting streets in winter Challenging to regulate (TMDL) 2. 2.Pollutants a. a.Priority (120) & Non-priority (47) – EPAEPA b. b.Standards Criteria maximum concentrations Criterion continuous concentration

I. I.Water Pollution – Sources and Effects B. B.Sources 3. 3.Other factors Factors besides anthropogenic chemical pollutants can degrade water quality a. a.Removal of adjacent vegetation Destabilization of shoreline Removal of shade destabilizes temperatures b. b.Siltation Increased turbidity  reduced vision, photosynthesis Burial of organisms, filling of water body c. c.Alteration of drainage patterns Damming, dredging, channelization Changes flow speed, volume, predictability d. d.Deforestation within the watershed Affects chemistry, flow patterns, sediment load e. e.Leaching of chemicals from natural deposits Salts, nutrients, metals f. f.Warm weather Raises temperatures, reduces oxygen solubility, may dry up g. g.Natural organic chemicals Tannic acids from decaying leaves  brown water, low pH 4. 4.Interfere with designated beneficial uses Different beneficial uses for different water bodies  different factors of interest, different methods for remediation

II. II.Water Pollution – Components A. A.Oxygen-Depleting Substances Pollutants may lower O 2 concentrations directly or indirectly Usually biodegradable (organic wastes) Reduced O 2 levels can influence species composition in a water body Ex – salmon and trout are sensitive to O 2 levels Low O 2 levels also favor survival of anaerobic bacteria, many of which produce noxious gases (H 2 S, CH 4 ) Examples 1) 1)Sewage (including animal and plant materials) 2) 2)Agricultural waste (leaves, plant debris) 3) 3)Manure 4) 4)Food processing wastes Toxic wastes can kill aquatic organisms, leading to O 2 depletion by decomposing bacteria Warm temperatures exacerbate O 2 depletion Reduce solubility of oxygen Accelerate bacterial decomposition rates

II. II.Water Pollution – Components B. B.Infectious Agents Pathogenic bacteria Common components of animal wastes Can produce outbreaks of typhoid, cholera, salmonellosis, infectious hepatitis, dysentery (affect billions of people) Examples Giardia causes swimmer’s itch by irritating skin but can cause intestinal problems internally Cryptosporidium contaminated Milwaukee water supply in 1993 More than 400,000 people with symptoms and 100+ deaths Cysts passed through filtration in water treatment system and went undetected Very difficult to scan water bodies for all potential pathogens (problem: lag time b/w test & results) Use of indicator organisms (coliform bacteria, enterococci) Possible sources (source identification challenging) 1) 1)Municipal sewage – Inadequately treated or spilled 2) 2)Stormwater drains 3) 3)Septic systems 4) 4)Runoff from livestock pens 5) 5)Sewage from recreational vehicles (boats, campers)

II. II.Water Pollution – Components C. C.Toxic Organic Chemicals (TOCs) Usually synthetic chemicals Persistent organic pollutants (POPs) Polychlorinated biphenyls (PCBs) Polycyclic aromatic hydrocarbons (PAHs) Dioxins Herbicides, pesticides (Ex: chlordane, DDT) Characteristics Bioavailable – readily assimilated Lipid soluble – incorporated into lipid deposits Bioaccumulate – concentrations increase with time and exposure Biomagnify – concentrations increase through food web Tend to be resistant to degradation Facilitates wide dispersal Long residence times (persistence) Ex – DDT near White Point Effects – Poorly understood for most compounds CNS damage Liver damage Birth defects

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Beach on Long Island, NY

II. II.Water Pollution – Components C. C.Toxic Organic Chemicals (TOCs) Usually synthetic chemicals Persistent organic pollutants (POPs) Polychlorinated biphenyls (PCBs) Polycyclic aromatic hydrocarbons (PAHs) Dioxins Herbicides, pesticides (Ex: chlordane, DDT) Characteristics Bioavailable – readily assimilated Lipid soluble – incorporated into lipid deposits Bioaccumulate – concentrations increase with time and exposure Biomagnify – concentrations increase through food web Tend to be resistant to degradation Facilitates wide dispersal Long residence times (persistence) Ex – DDT near White Point Effects – Poorly understood for most compounds CNS damage Liver damage Birth defects

II. II.Water Pollution – Components C. C.Toxic Organic Chemicals (TOCs) Usually synthetic chemicals Persistent organic pollutants (POPs) Polychlorinated biphenyls (PCBs) Polycyclic aromatic hydrocarbons (PAHs) Dioxins Herbicides, pesticides (Ex: chlordane, DDT) Characteristics Bioavailable – readily assimilated Lipid soluble – incorporated into lipid deposits Bioaccumulate – concentrations increase with time and exposure Biomagnify – concentrations increase through food web Tend to be resistant to degradation Facilitates wide dispersal Long residence times (persistence) Ex – DDT near White PointWhite Point Effects – Poorly understood for most compounds CNS damage Liver damage Birth defects

II. II.Water Pollution – Components C. C.Toxic Organic Chemicals (TOCs) Usually synthetic chemicals Persistent organic pollutants (POPs) Polychlorinated biphenyls (PCBs) Polycyclic aromatic hydrocarbons (PAHs) Dioxins Herbicides, pesticides (Ex: chlordane, DDT) Characteristics Bioavailable – readily assimilated Lipid soluble – incorporated into lipid deposits Bioaccumulate – concentrations increase with time and exposure Biomagnify – concentrations increase through food web Tend to be resistant to degradation Facilitates wide dispersal Long residence times (persistence) Ex – DDT near White Point Effects – Poorly understood for most compounds CNS damage Liver damage Birth defects

II. II.Water Pollution – Components D. D.Other Chemicals and Minerals 1. 1.Acids and acidifying compounds Many originate in the atmosphere (sulfuric acid, nitric acid) or from runoff passing through mine tailings Aquatic organisms generally intolerant of low pH Effects 1) 1)Irritates gills of fishes and crustaceans and interferes with gas exchange 2) 2)Irritates slime layer of fishes (reduces resistance to pathogens) 3) 3)Erodes shells of aquatic mollusks and arthropods 4) 4)Impedes ability of crustaceans to recalcify after molting 5) 5)Facilitates release of toxins bound to particles in sediments

II. II.Water Pollution – Components D. D.Other Chemicals and Minerals 1. 1.Acids and acidifying compounds Many originate in the atmosphere (sulfuric acid, nitric acid) or from runoff passing through mine tailings Aquatic organisms generally intolerant of low pH Effects 1) 1)Irritates gills of fishes and crustaceans and interferes with gas exchange 2) 2)Irritates slime layer of fishes (reduces resistance to pathogens) 3) 3)Erodes shells of aquatic mollusks and arthropods 4) 4)Impedes ability of crustaceans to recalcify after molting 5) 5)Facilitates release of toxins bound to particles in sediments

II. II.Water Pollution – Components D. D.Other Chemicals and Minerals 2. 2.Nutrients Nitrates, nitrites, phosphates Common sources 1) 1)Crop and lawn fertilizers 2) 2)Manure 3) 3)Sewage 4) 4)Detergents containing phosphates and nitrates Excessive nutrient loading  eutrophication Effects 1) 1)Plant growth can clog waterways (ecology, navigation) 2) 2)Plants can interfere with recreation (swimming, boating) 3) 3)Algal growth can impede submerged plant growth 4) 4)Nighttime oxygen depletion 5) 5)Nitrate  methemoglobinemia (blue baby syndrome) Nutrients can be difficult to control once in a system Recycling and regeneration Eutrophied water bodies can recover if sources are removed Ex – Lake Washington