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Water Quality. Water quality problems in developing countries. Evidence from the WHO: In 2003, an estimated 1.6 million deaths worldwide were caused by unsafe drinking water and sanitation 90% of these deaths were among children under age five
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Water quality problems in developing countries • Evidence from the WHO: • In 2003, an estimated 1.6 million deaths worldwide were caused by unsafe drinking water and sanitation • 90% of these deaths were among children under age five • 1.1 billion people don’t have access to improved water sources • 2.4 billion people don’t have access to improved sanitation Source: www.who.int/water_sanitation_health/wsh0404/en/
Water quality problems in developing countries • Biggest water quality problem in developing countries is the threat of infectious diarrhea caused by water-borne diseases. • If there was a 50% reduction in the number of people lacking access to in-house piped water and sewer connections with partial treatment of waste waters, the number of illnesses would be reduced by an average of 69% in affected regions. • http://www.who.int/water_sanitation_health/hygiene/envsan/lookingback/en/
Water quality problems in the U.S. The Cuyahoga River Fire in 1969 • Floating debris and oil caught fire on the surface of the Cuyahoga River near downtown Cleveland in 1969. • The Cuyahoga River had also ignited a couple of times in earlier years. • The Cuyahoga River fire brought water-quality problems to the attention of the public and Congress. Photos: http://www.cwru.edu/artsci/engl/marling/60s/pages/richoux/Photographs.html
Water quality problems in the U.S. Cryptosporidium contamination in Milwaukee in 1993 • Cryptosporidium is a protozoan parasite that’s usually present at low levels in water supplies. • An outbreak of cryptosporidium contamination in 1993 in Milwaukee caused diarrhea, fever, and other symptoms for over 400,000 residents and killed more than 100. • The contamination was traced to a water treatment plant that had inadequately filtered water from Lake Michigan. • It is believed that the original source of the contamination was storm runoff from nearby farms.
Water quality problems in the U.S. Narrowing the focus: • Surface water pollution • Groundwater pollution Types of surface water pollution: • Pollution from point sources • Nonpoint-source pollution Regulation depends on designated uses of surface water: • Drinking water supply • Recreational uses (such as swimming) • Aquatic life support • Fish consumption • etc.
Examples of Water Contaminants • Contaminants affecting human health: • Organic compounds (such as pesticides and gasoline) • Heavy metals (such as mercury and lead) • Pathogens (such as cryptosporidium) • Contaminants affecting aquatic life: • Plant nutrients, including nitrate and phosphorus compounds • Organic wastes, which lead to depletion of dissolved oxygen in the water
Federal Water Quality Legislation • Federal Water Pollution Control Act of 1972 • Clean Water Act of 1977 • Water Quality Act of 1987 • “The Year of Clean Water”: 2002-3
Water Quality Control: An Overview • Control of point-source pollution • Federal government sets water-quality standards • States create pollution-control programs to meet the standards • Programs usually require polluters to install certain pollution-control technologies • Subsidies for construction of Publicly Owned Treatment Works (POTWs) • Control of non-point source pollution
Water Quality Control: An Overview The effect that a particular effluent has on water quality depends on a number of factors such as: • biochemical oxygen demand in the effluent • time of year and water temperature • location of waste sources • turbulence of water flow • volume of water flow A perfect water pollution control policy would have to take all these factors into account. Since this is impractical, actual policies involve compromises.
Water Treatment Facilities • Since 1970 the federal government has spent over $60 billion to subsidize construction of POTWs, and total spending by all levels of government has been over $200 billion. • Evidence suggests that federal funding for POTW construction has largely just replaced local funding – about 67% of construction would have taken place anyway. • Federal subsidies provided perverse incentives at first: • Municipalities had an incentive to build POTWs that were too large. • Federal funding didn’t help to cover operating expenses and maintenance. • But more responsibility has been shifted to local authorities. • Progress has been significant: http://www.epa.gov/owm/wquality/
Control of Other Point Sources • Basic federal program: National Pollutant Discharge Elimination System (NPDES) • Administered through a system of permits that set effluent limits; but these permits are typically not tradable. • Goal is zero discharge; but limits are usually based largely on what level of control is technically feasible. • Efficiency? Cost-effectiveness? EPA – Envirofacts WDNR - WPDES Permit Program
Point-Source Control: Other Options • Effluent taxes or fees? • In theory, this is could be an effective approach. • Effluent taxes have been used in Europe, but the taxes are usually set too low to provide strong incentives to reduce pollution levels. • Best example: the Netherlands has used effluent fees as an effective pollution-control approach. • Why not use effluent taxes? • Political objections • Concerns that taxed firms will face a competitive disadvantage • Effluent taxes require careful monitoring of discharges
Point-Source Control: Other Options • Tradable effluent permits • EPA > Watersheds > Trading > Frequently Asked Questions About Water Quality Trading • Advantages of effluent permit trading • Cost-effectiveness • Problems with effluent permit trading • Hot spots?
Control of Pollution from Non-Point Sources • Major remaining water pollution problem, especially in agricultural states like Wisconsin. • Two important sources: • Agricultural runoff • Storm runoff
Control of Pollution from Non-Point Sources • Control of agricultural runoff: the DNR provides: • Technical assistance to farmers • Subsidies for improvements to prevent runoff • Performance standards • Control of storm runoff • Storm runoff performance standards for industry, municipalities, and construction sites • In Eau Claire, new businesses must pay fees based on their likely runoff.