Urbanization and Water

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Transcript Urbanization and Water

In 2002, the United Nations Committee on Economic, Social and Cultural Rights, the Covenant’s supervisory body, adopted a General Comment stating “the right to water clearly falls within the category of guarantees essential for securing an adequate standard of living, particularly since it is one of the most fundamental conditions for survival.”

Why does defining water as a human right make a difference?

Ensuring that access to sufficient safe water is a human right constitutes an important step towards making it a reality for everyone. It means that: ● fresh water is a legal entitlement, rather than a commodity or service provided on a charitable basis; ● achieving basic and improved levels of access should be accelerated; ● the “least served” are better targeted and therefore inequalities decreased; ● communities and vulnerable groups will be empowered to take part in decision-making processes; ● the means and mechanisms available in the United Nations human rights system will be used to monitor the progress of States Parties in realizing the right to water and to hold governments accountable.

Worldwide net renewable water distribution by region and per capita. Data as of early 1990s. source: www.worldbank.org/html/extdr/offrep/mena/Focus/BOOKLET.ARA.html]

Region

Oceania Latin America North America Easter Europe 1

Net Annual Renewable Water Resources

(Billions cubic meters) 769 10,766 5,379 7,256 Africa Western Europe 4,184 1,985 Asia MENA 2 9,985 355 1 includes Central Asia 2 Middle East/North Africa

Population

(millions) 21 466 287 495 559 383 3,041 284

Per capita Water Availability

(cubic meters) 36,619 23,103 18,742 14,659 7,485 5,183 3,283 1,250

Urbanization and Water

    Water is a key issue in urban areas. The intensity of demand in cities can quickly exceed local supply.   The price of water is typically lower than the actual cost of obtaining, treating and distributing it, partly because of government subsidies.  Pollution from urban run-off, sewage and untreated discharges of industries has adversely affected many water bodies, leaving many cities with unsafe water supply.

Urbanization and Water

• Sewers and drains • Runoff • Erosion • Pollutants • Water and health

Water Runoff

• Urbanization has had significant impacts on the hydrology of the environment by controlling: • Nature of runoff (water from precipitation or irrigation that does not evaporate or seep into the soil but flows into rivers, streams, or lakes, and may carry sediment); • Rates of soil erosion; and • Delivery of pollutants to rivers, streams, lakes and ocean.

AMDC Land Cover

• Impervious surfaces and sewers cause runoff after a rainstorm to occur more rapidly and with a greater peak flow that under non-urban conditions.

Sewers and Drains

• Sewers and drains carry domestic and industrial wastes that might have been widely deposited on the soil, but have been channeled into rivers and other bodies of water.

• The storm sewer system is designed to carry the excess water that flows over land during and after a rainfall directly into a river, stream or lake.

• The sanitary sewer system carries sewage from residential, commercial, and industrial sources to the waste water treatment plant.

• At a waste water treatment plant most harmful substances are removed from sewage before it is piped to a nearby body of water.

Illicit Connection

• viewgraph

Effect of urbanization on floods

• Urbanization increases the intensity and decreases the lag time of floods.

• In unurbanized areas small floods occur frequently, while large flood events occur infrequently.

• Urbanization increases the frequency of small floods.

• The size of small floods is increased by urbanization, while during large, infrequent floods there are no significant differences between the way rural and urban areas behave.

EROSION

• Runoff on bareland leads to erosion.

• Grass, trees and other plants hold the soil in place and avoid erosion.

• The highest rates of erosion are produced in urban areas during construction.

• Erosion is the source of sediment that fills streams, pollutes water, kills aquatic life, and shortens the useful life of dams and reservoirs.

• viewgraph

Rates of erosion

Table 2: Comparison of containment profiles for the urban surface runoff and raw domestic sewage, based on surveys throughout USA Constituent *

Suspended solids BOD # Nutrients (a) Total nitrogen (b) Total phosphorus Coliform bacteria (MPN/100 ml) Chlorides Nutrients (a) Oil and grease (b) Heavy metals (c) Pesticides (d) Other toxins

Urban surface runoff

250 - 300 10 - 250 0.5 - 5.0

0.5 - 5.0

20 - 100 yes yes 10^4 - 10^6 (10 - 100) times sewage conc.

potential exists

Raw domestic sewage

300 - 350 25 - 85 2 - 15 10^6 or greater 15 - 75 traces seldom seldom * All concentrations are expressed in mg l^-1 unless stated otherwise # Biochemical oxygen demand MPN - Most probable number yes 150 - 250

Water Pollution

• Point source pollution – Industrial plant effluent pipe • Non-Point source pollution – Surface runoff from precipitation; responsible for most pollution.

Pollution includes: Chemicals, sediments, heat, disease causing organisms

Water Pollutants

• Suspended solids – decrease in photosynthesis • Coliform Bacteria – if present in amounts greater than 200 colonies/ml of water, it is likely that other pathogens are present.

• Chlorides – salt for de-icing • Phosphorus and nitrogen – plant nutrients

Biochemical Oxygen Demand Oxygen enters water by:

•Ocean Spray •Waves •Photosynthesis of algae and large aquatic plants O 2 Dissolved in Water

Oxygen depletion by:

Decomposition of organic material by bacteria Respiration of organisms

Enhancement in Dissolved Nutrients (phosphorus and nitrogen) Algae growth Cultural Eutrophication Decomposition by bacteria Depletion of O 2

Solutions to Runoff in Urban Areas • viewgraph

Health Effects of Pollutants

The relationship between water resources and health has occupied a position of special significance throughout human history.

Sewage Industrial Pollutants Infectious Diseases Non-infectious Diseases- cancers, infertility thyroid dysfunction, birth defects, behavior problems, immune system suppression, deformities, etc.

Common diseases transmitted to humans through contaminated drinking water. From Miller (1995).

Type of Organism Disease

Bacteria Typhoid fever Cholera

Effects

Diarrhea, severe vomiting, enlarged spleen, inflamed intestine; often fatal if untreated Diarrhea, severe vomiting, dehydration, often fatal if untreated Viruses Parasitic Protozoa Parasitic worms Bacterial dysentery Enteritis Infectious hepatitus Amoebic dysentery Giardia Schistosomiasis Diarrhea, rarely fatal except in infants without proper treatment Severe stomach pain, nausea, vomiting, rarely fatal Fever, severe headache, rarely fatal but may cause permanent liver damage Severe diarrhea, headache, fever, if not treated can cause liver damage and death Diarrhea, cramps, flatulence, fatigue Abdominal pain, rash, anemia, chronic fatigue

Health Effects of Pollutants

Synthetic chemicals in pesticides and industrial products have been identified as hormone disruptors Like hormones, these chemicals affect the endocrine systems of animals and humans in minute amounts – parts per trillion.

A vast number of man-made chemicals and chemical by-products have been identified as potential hazards. Some environmental groups and scientists have focused attention on: dioxins PCBs DDT and its metabolites Other Pesticides (including other organochlorines, and the triazines) alkylphenol ethoxylates PVC products bisphenol-A, phthalates pulp and paper production effluents spermicides and condom lubricants

Hormone Disruptors

•Mimic naturally produced hormones such as estrogen and testosterone.

•Hormone blockers “lock up” a cell receptor”preventing naturally produced hormones from entering and performing their function.

•Trigger set off reactions in the cell that would not normally be produced by a hormone. Dioxin acts this way.

Hormone Disruptors

• Mostly affects the offsprings of exposed organisms.

• Health effects on humans include lower sperm counts, undescended testicles, early puberty, and thyroid dysfunction.

• In wildlife, the health impacts include smaller penises, and/or testicle size, undescended testicles, lower sperm count, reproductive abnormalities, thyroid dysfunction, feminization of males or masculinization of females.

Where do we find them?

• Endocrine-Disrupting Chemicals such as nonylphenol, alkylphenol ethoxylates (APEs) and phthalates are often found in common household items, such as detergents, cosmetics, household cleaners as well as even plastic food containers. • Several pesticides contain known or suspected endocrine disrupters that enter our bodies through residues on food. Heavy metals like lead, mercury and cadmium may be tracked in from outdoors.

The Economics of Pollution Control at the Local and Global Levels

The efficient level of pollution control • Government intervention • Clean Air Act/Clean Water Act • Emission control policies • Reducing pollution at the global level • The Montreal and Kyoto Protocols

Environmental Economics views the economy in which we live and work as an “ open system ”.

Process Resources Dispose of large amounts of dissipated and/or chemically transformed resources back into the environment.

Pollution Resource Depletion Extract resources from the environment - renewable and exhaustible resources

Why do we pollute?

Pollution –waste that has been disposed off in the air, in water, or on land, and that reduces the value of those resources for alternative uses.

In the case of air and water pollution, the damage is done because they are open access resources , i.e. no one owns them, and there is no individual incentive to restrict pollution.

Pollution reduction is an economic problem: How much money are we willing to spend to reduce pollution?

• Ideal world – high no pollution –costs would be very • The other extreme is to live in a world with no pollution control • The real world is somewhere in between these two extremes, i.e., it is necessary to achieve a balance between the costs and social benefits of reducing pollution.

Efficient Pollution Control

The efficient level of Pollution Control strikes a balance between the Social Benefit and the Social Cost involved in reducing pollution.

Marginal social cost The efficient level of pollution control corresponds to the percent reduction in polluting emissions for which the marginal social benefit equals the marginal social cost.

Marginal social benefit 0

80 100% Reduction in polluting emissions (percent per year)

Social benefits are measured by the reduction in damages caused by Pollution to human health and to natural resources.

Costs and Benefits of CFC control in the United States

Costs of reducing CFC emissions (in billions 1985$) Costs

1989-2075 discounted at 2% Health and environment benefits Net benefit

No control

0 0 0

80% cut in emissions

22 3553 3531 Source: US Environmental Protection Agency (1988)

The Montreal Protocol

• The Protocol on substances that deplete the ozone layer, signed in 1987, established a timetable for diminishing CFC emissions and the use of bromine compounds, both of which destroy ozone. • In November 1992, representatives from half the nations of the world met in Copenhagen to revise the treaty. Provisions of the meeting called for a quicker phase-out of the previously targeted ozone destroying chemicals.

NO POLLUTION CONTROL

Production of Goods Cost of Production Consumer Environmental Pollution Negative Externality Taxpayer

Costs: Cleaning environment Health problems

Mechanisms to achieve pollution reduction Free market transactions are usually unregulated: there is no mechanism for charging polluters a fee to correct for the damage done by their emissions. Society decides on an acceptable level of environmental quality Government Intervention

Government Intervention: Subsidies based on Cost-Benefit Analysis

Industrial Production

Cost of Production

Consumer Reduced Environmental Emissions Taxpayer

Subsidies: •Tax Incentives •Credits

Government Intervention: Regulations

Government Regulated Industrial Production Cost of production (Possibly increased) Consumer Reduced Environmental Pollution

What is the Clean Air Act?

The Clean Air Act is the federal law designed to make sure that all Americans have air that is safe to breathe. Main Goals : • Public health protection is the primary goal.

• The law also seeks to protect our environment from damage caused by air pollution.

When was the Clean Air Act passed?

Congress passed the core provisions of the Clean Air Act in 1970 . The law was amended in 1977 and again in 1990 to extend deadlines but also to specify new strategies for cleaning up the air. The basic framework of the law and its public health objective have remained intact.

How does the Clean Air Act work?

The Clean Air Act requires that: • The U.S. Environmental Protection Agency sets national health based air quality standards to protect against common pollutants including ozone (smog), carbon monoxide, sulfur dioxide, nitrogen dioxide, lead, and particulate soot. EPA is directed to review these standards every five years.

• State governments must devise cleanup plans to meet the health standards by a specific date . Areas with the worst smog have a longer time to meet the standards.

How does the Clean Air Act work?

• In addition, the EPA sets national standards for major new sources of pollution including automobiles, trucks and electric power plants. • The agency also is charged with developing controls for major sources of toxic pollutants , such as benzene.

How well has the Clean Air Act worked?

By any objective measurement, the act has been a tremendous success: • The air is cleaner and public health has improved.

• Emissions of toxic lead have dropped 98 percent.

• Emissions of sulfur dioxide have dropped by 35 percent even though the gross domestic product has more than doubled. • Emissions of carbon monoxide have dropped by 32 percent even though driving has increased 127 percent. • Even so, many areas of the country still violate the basic health standards, and the health of tens of millions of Americans remains at risk.

1997 Changes to the Clean Air Act

In 1997, EPA completed its review of standards for 2 of the 6 specific pollutants covered by the CAA, and promulgated new, more stringent standards for PM and ozone.

The new ozone standard lowered both the amount of ozone that can be detected and expanded the monitoring time to eight hours, referred to as the "8-hour ozone standard".

"For particulate matter", EPA added to its current standards a limit on the amounts of fine particulates (smaller than 2.5 micrometers) that can be detected over a twenty-four hour period.

Update on the Clean Air Act

The Clean Air Act requires new power plants to install state-of-the art pollution controls, and lets power plants constructed before 1978 cough up otherwise illegal levels of pollutants until the plants are renovated. The Bush administration plan effectively repeals these air quality safeguards. Exemptions are not limited to power plants, but are available to plants in any industry sector.

The net effect of these change is an increase in SO 2 over the levels expected under the current law. and NO x

Top Polluters

Fifty-one American power plants, emit a disproportionate amount of pollution.

Total emission from 500 plants, 1999 in millions of tons.

Updates on the Clean Air Act

• Power plants are the largest source of US global warming pollution, responsible for 40% of US carbon dioxide emissions. • The current administration policy allows power plant CO 2 pollution to continue to increase, relying instead on voluntary approaches.

Updates to the Clean Air Act

• Power plants are the largest uncontrolled source of mercury. According to the Clean Air Act, each power plant must install the maximum achievable control technology (MACT) for mercury emissions and other toxic air pollutant by the end of 2007, and then further limit any unacceptable health risks that remain. EPA estimates that enforcing current law could cut power plant mercury pollution by nearly 90% by 2008. Administration policies eliminate current law’s health protection for mercury and other toxic air pollutants. Mercury reductions are delayed and diluted, allowing power plant to emit more than 5 times as much mercury for a decade longer.

The Clean Water Act

The Clean Water Act (CWA), intended to ". . .restore and maintain the chemical, physical, and biological integrity of the Nation's waters". To accomplish that objective, the act aimed to attain a level of water quality that "provides for the protection and propagation of fish, shellfish, and wildlife, and provides for recreation in and on the water" by 1983 and to eliminate the discharge of pollutants into navigable waters by 1985.

The CWA has five main elements:

(1) A system of minimum national effluent standards for each industry . The CWA requires the EPA to establish effluent limitations for the amounts of specific pollutants that may be discharged by municipal sewage plants and industrial facilities.

(2) Water quality standards.

The two-step approach to setting the standards includes: (a) establishing a nationwide, base-level treatment through an assessment of what is technologically and economically achievable for a particular industry and (b) requiring more stringent levels of treatment for specific plants necessary to achieve water quality objectives for the particular body of water into which that plant discharges. if

(3) A discharge permit program that translates these standards into enforceable limits.

Under the National Pollutant Discharge Elimination System program any person responsible for the discharge of a pollutant or pollutants into any waters of the United States from any point source must apply for and obtain a permit.

(4) Provisions for special problems such as toxic chemicals and oil spills, and (5) A revolving construction loan program for publicly-owned treatment works.

Update on the Clean Water Act

• For many years following the passage of CWA in 1972, EPA, and states focused mainly on the chemical aspects of the "integrity" goal. • Also, in the early decades of the Act's implementation, efforts focused on regulating discharges from traditional "point source" facilities, such as municipal sewage plants and industrial facilities, with little attention paid to runoff from streets, construction sites, farms, and other sources.

Update on the Clean Water Act

• Starting in the late 1980s, efforts to address polluted runoff have increased significantly. For "nonpoint" runoff, voluntary programs, including cost-sharing with landowners are the key tool. For "wet weather point sources" like urban storm sewer systems and construction sites, a regulatory approach is being employed.

• Evolution of CWA programs over the last decade has also included something of a shift from a program-by program, source-by-source, pollutant-by-pollutant approach to more holistic watershed-based strategies.

Latest Development on the CWA

On January 15, 2003 the EPA and the Corps of Engineers issued “guidance” and advance notice of a “proposed rule” that have critical implications for the types of wetlands, streams, lakes and ponds that are entitled to federal protection under the Clean Water Act. Stripping those waters of protection will open the way for developers, agribusiness, industry, and other polluters to discharge their pollution into, and fill in and develop, many kinds of wetlands, small streams, ponds or other waters.

On 12/16/03 the EPA withdrew the proposal to weaken the Clean Water Act.

Emission Control Policies

Emission charges are prices established for the right to emit a unit of a pollutant.

Emission standards are limits established by government on the annual amounts and kinds of pollutants that can be emitted into the air or water by producers or users of certain products.

Command and control regulation : a system or rule that requires the use of specific pollution control devices on certain sources of pollution or applies strict emission standards to specific emitters.

• Emission offsets allows a new firm to be established in an area where additional polluting emissions resulting from the firms operations normally would prevent the firm from being approved by EPA. Under this policy the new firm, before it is approved, most induce other firms in the area to reduce emissions usually through a cash payment.

• The Bubble allows a firm to exceed the amount of emission of a pollutant if it reduces another pollutant by more than the current standard.

• Banking of emissions : a firm that emits less than the specified level of a pollutant is given a credit that allows them to emit more than the standard at some time in the future. The firm is also allowed to sell these credits for cash to other firms who want to exceed the standards.

Pollution rights : a government-issued permit allowing a firm to emit a specified quantity of polluting waste.Ex. Michigan’s Air Emissions Trading Program.

Advantages: •Pollution permits are tradable at free market prices.

•Regulatory authorities can control the amount of pollution by limiting the number of certificates.

•Provides a choice: purchase permits and pollute or reduce pollution and save the cost of permits.

•Provides an incentive to reduce emissions in order to sell previously purchased pollution rights.

Disadvantages: •A firm in a very polluted region is allowed to buy emission permits from a firm in a region where there is no pollution.

Failure of Government Intervention

• They may favor the interests of some part of the community rather than the community as a whole.

• Governments are not very good at obtaining the right information about the full consequences of a particular action.

• They may have problems translating good intentions into practice because of lack of competence among the government bureaucracy.

Reducing pollution at the global level

In some instances pollution is the result of activities at the global level and nations may be required to implement international agreements that address current pollution practices: • The Montreal Protocol • The Kyoto Protocol

Definitions:

• Protocol – A preliminary memorandum often formulated and signed by diplomatic negotiators as a basis for a final convention or treaty; examples: Montreal Protocol, the Kyoto Protocol on Climate Change.

• Convention – An agreement between states for regulation of matters affecting all of them (Merriam Webster’s Collegiate Dictionary, Tenth Edition); example: The United Nations Framework Convention on Climate Change.

Party – a state which has consented to be bound by a treaty and for which the treaty is in force.

Date of adoption – when states participating in the negotiation of a treaty agree on its final form and content.

Date of signature – when a state expresses its consent to be bound by a treaty.

Date of ratification – when a state makes a final formal expression of its consent to be bound by a treaty.

Date of entry into force – when a treaty becomes binding upon the states which have expressed their willingness to be bound by it. This is usually triggered by a clause in the text of the treaty saying something like “ this treaty shall enter into force when n states have signed it …”.

Comparison between Ozone Depletion and Global Climate Change Issues

Ozone Depletion Global Climate Change Causes and well understood a lot of consequences uncertainties of inaction and discrepancies Response Montreal Protocol: Kyoto Protocol: relatively little far-reaching, impact on costly and economies controversial and lifestyles changes