Water PollutionOUTLINEIntroductionSlide 4Slide 5Slide 6Slide 7Types of Pollutants [Fund and accumulating pollutants]Slide 9II) Accumulating/stock pollutantsWater Pollution Control Policy: Domestic Dimension [U.S.]Slide 12Slide 13Domestic policy on international waters: OceanDomestic Policy on Non-Point sourcesInternational Dimension: Transboundary watercoursesInternational WatercoursesPollution permissible uses.1997 UN Watercourses ConventionUnusual examplePROTECTION OF MARINE ENVIRONMENTSlide 22I) On land-based sourcesInternational Policy on DumpingIII) POLLUTION FROM SHIPSResponsibility and Liability for DamageConclusionWater PollutionWater PollutionOUTLINEOUTLINEIntroductionIntroductionWater subject to pollutionWater subject to pollutionPollutantsPollutantsDomestic PolicyDomestic PolicyInternational PolicyInternational PolicyInternational watercourseInternational watercourseMarine PollutionMarine Pollution•Development of regime Development of regime Land-based SourcesLand-based SourcesDumpingDumpingPollution from ShipsPollution from Ships•LiabilityLiabilityConclusionConclusionIntroductionIntroductionTwo Two types of water subject to pollutiontypes of water subject to pollutionSurface water – rivers, lakes, oceansSurface water – rivers, lakes, oceansUses: drinking, recreational [fishing, boating, Uses: drinking, recreational [fishing, boating, swimming], irrigation.swimming], irrigation.Groundwater- occurs beneath a water table in Groundwater- occurs beneath a water table in soils or rocks; subject to pollution from soils or rocks; subject to pollution from toxic chemicals.toxic chemicals.Uses: drinking, irrigation, etcUses: drinking, irrigation, etcContaminationContamination Nature of sources of contamination [point and non-Nature of sources of contamination [point and non-point]point]Point source: discharge into surface waters at a Point source: discharge into surface waters at a specific location through a pipe, outfall or ditch.]specific location through a pipe, outfall or ditch.]Non-point: Indirect or Non-point: Indirect or diffuse effect on water diffuse effect on water [N/B. more difficult to [N/B. more difficult to control]control]e.g. agricultural e.g. agricultural activities, urban run-offactivities, urban run-offSources of contaminationSources of contaminationFor GroundwaterFor Groundwater•-polluting substances leach into a water--polluting substances leach into a water-saturated region [e.g. toxic chemicals]saturated region [e.g. toxic chemicals]•-Mainly due to migration of pollutants from -Mainly due to migration of pollutants from sites with high concentrations of chemicals sites with high concentrations of chemicals [e.g. industrial waste sites and farms][e.g. industrial waste sites and farms]Sources of contaminationSources of contaminationFor Surface waterFor Surface water•Rivers and lakesRivers and lakesPoint source: -sewage [municipal or private]Point source: -sewage [municipal or private]- - industrial wastesindustrial wastesNon-point source:Non-point source:•Agricultural activity [e.g. pesticides, fertilizers].Agricultural activity [e.g. pesticides, fertilizers].•urban and highway water runoff.urban and highway water runoff.•Ocean [oil spills, dumping, land-based sources]Ocean [oil spills, dumping, land-based sources]Oil spills – during transportation, either accidentally or Oil spills – during transportation, either accidentally or intentionallyintentionallyDumping –sewage, chemical disposal, radioactive Dumping –sewage, chemical disposal, radioactive materialsmaterialsLand-based sources –migration of chemical Land-based sources –migration of chemical substances.substances.Types of Pollutants [Fund and accumulating pollutants]Types of Pollutants [Fund and accumulating pollutants]I) Fund pollutants I) Fund pollutants -Environment has some assimilative capacity. If -Environment has some assimilative capacity. If capacity for absorption higher than rate of injection, they capacity for absorption higher than rate of injection, they may not accumulate. may not accumulate. a) a) DegradableDegradabledegrades/break into component parts within water. Are degrades/break into component parts within water. Are normally organic residuals attacked and broken down by normally organic residuals attacked and broken down by bacteria and become less harmful.bacteria and become less harmful.b) Thermal pollutionb) Thermal pollutioncaused by injection of heat into watercourses by an caused by injection of heat into watercourses by an industrial plant or electric utility using surface water industrial plant or electric utility using surface water as a coolant, and returning the heated water to the as a coolant, and returning the heated water to the watercourse.watercourse. c) Plant nutrientsc) Plant nutrients [nitrogen and [nitrogen and phosphorus][eutrophic/ phosphorus][eutrophic/ eutrophication =excess supply of nutrients in a lake]eutrophication =excess supply of nutrients in a lake]stimulate growth of aquatic plant life, e.g. algae and water stimulate growth of aquatic plant life, e.g. algae and water weeds.weeds.can produce odor if in excesscan produce odor if in excess..d) Infectious organismsd) Infectious organisms [e.g. bacteria and viruses [e.g. bacteria and viruses]]carried into both ground and surface water by domestic and carried into both ground and surface water by domestic and animal wastes; industrial wastes e.g. tanning and meat animal wastes; industrial wastes e.g. tanning and meat packagingpackagingAre live organisms that may thrive and multiply in water or Are live organisms that may thrive and multiply in water or declinedecline..II) Accumulating/stock pollutantsII) Accumulating/stock pollutantsEnvironment has little or no absorptive capacity [i.e. no Environment has little or no absorptive capacity [i.e. no natural process removes/transforms them].natural process removes/transforms them].accumulate over time.accumulate over time.Examples: non-biodegradable bottles, heavy metals [e.g. Examples: non-biodegradable bottles, heavy metals [e.g. lead, mercury]; persistent synthetic chemicals [e.g. dioxin, lead, mercury]; persistent synthetic chemicals [e.g. dioxin, and PCBs –polychlorinated biphenyls]and PCBs –polychlorinated biphenyls]not easily broken down; so can remain in water