4/19/07 Water supply & usage (cont.) (Chapter 10) Water Law (Chapter 18) Groundwater pollution...

4/19/07

• Water supply & usage (cont.) (Chapter 10)

• Water Law (Chapter 18)

• Groundwater pollution & remediation (Chapter 16)

Water Distribution in San Diego in San Diego County

58%25%

11%6%

residentialcommercial/industrialagriculturalother

California’s Plight

Last 5 years have used 5.2 million acre feet of waterLast 5 years have used 5.2 million acre feet of water MWD gets from other states’ surplus but growing use in MWD gets from other states’ surplus but growing use in

other states will render surplus non existentother states will render surplus non existent Single SourceSingle Source

-MWD-MWD Population Population

-1.14% growth annually-1.14% growth annually

Conservation: Ways to Save Outdoors

water landscape twice weeklywater landscape twice weekly don’t use sprinklersdon’t use sprinklers use a broom to clean pavementuse a broom to clean pavement wash cars with hoses with positive shut-off nozzlewash cars with hoses with positive shut-off nozzle use covers on pools and spasuse covers on pools and spas plant drought-resistant trees and plantsplant drought-resistant trees and plants Fix leaksFix leaks

Projects and Programs

Emergency Storage ProjectEmergency Storage Project a system of reservoirs, interconnected pipelines & a system of reservoirs, interconnected pipelines &

pumping stationspumping stations Agricultural Water Management ProgramAgricultural Water Management Program surveyor comes to your acreage & makes observations of surveyor comes to your acreage & makes observations of

plant material, soil, and irrigation system…..it’s freeplant material, soil, and irrigation system…..it’s free

Projects and Programs

Commercial, Industrial, Institutional Voucher ProgramCommercial, Industrial, Institutional Voucher Program vouchers for replacing inefficient equipment with vouchers for replacing inefficient equipment with

efficient equipmentefficient equipment

Residential Survey ProgramResidential Survey Program owner receives a review of indoor/outdoor water-saving owner receives a review of indoor/outdoor water-saving

opportunities &educational literatureopportunities &educational literature

Map of Emergency Storage Project

www.sdcwa.org/text/esp/esp_faq.htm

What does this mean for San Diego: Factors for the Future Growing populationGrowing population- SANDAG predicts increased - SANDAG predicts increased

population over the next several yearspopulation over the next several years Federal restrictionFederal restriction Future demand for waterFuture demand for water- increasing population - increasing population

with less allocationwith less allocation demand for water in 2000: 619,409 AF demand for water in 2000: 619,409 AF

2015: 787,000 AF 2015: 787,000 AF Located in a vulnerable areaLocated in a vulnerable area-earthquakes, drought-earthquakes, drought

Table 10.4

Case Studies in Water Consumption(study these in your book)

• The Colorado River Basin

• The High Plains (Ogallala) Aquifer System

• The Aral Sea

Water law and legislation dealing with pollution

1) Surface water law

2) Groundwater law

Surface Water Law

• Riparian Doctrine– States in the eastern US– Owners of the land adjacent to a water

body own the water– Water rights are property that can be

bought and sold– Landowners can make “reasonable use” of

water on their land

Surface Water Law

• Prior Appropriation Doctrine– Western states– The first person to have diverted and used

the water has the primary right to it.– Water rights are separate from property

rights

Surface Water Law

• Public Trust Doctrine– It is the duty of the state to protect the

public’s common heritage• Streams, lakes, marshlands, etc.

– 1983, California Supreme Court used this doctrine to protect Mono Lake against Las Angeles, which had rights over the water

Groundwater Law

• Absolute Ownership Doctrine–(English Rule)

• A landowner owns the groundwater under his/her land

–Works fine if there is plenty of groundwater

–A problem in the western US

Groundwater Law

• Reasonable Use Doctrine–(American Rule)

• A landowner owns the groundwater under his/her land

• BUT, the amount of water withdrawn must be “reasonable” and “beneficial”.

Groundwater Law

• Correlative Rights Doctrine– California

• A landowner owns the groundwater under his/her land

• BUT, all of the landowners whose property overlies a common groundwater source also have equal rights to the water in the aquifer as long as it is “reasonable” and “beneficial”

• Requires “safe yield” be established

Water Pollution

Water Quality Standards

• 1974: Safe Drinking Water Act– Established MCL’s (Maximum Contaminant Levels)

for 26 contaminants

• 1986: Safe Drinking Water Act amended – to include a total of 83 contaminants

– to prohibit use of lead in drinking water systems

– Maximum Contaminant Level Goal (MCLG)

National Primary Drinking Water Standards

• Inorganics:– Arsenic, Cd, Pb, Hg, Asbestos, Fluoride

• Organics– Pesticides, herbicides

• Volatile organic chemicals– Benzene, Carbon Tetrachloride, Trichloroethylene,

Vinyl chloride• Microbiological organisms

– Fecal coliform MCL: 1 cell/100ml

12_T01

Common Pollutants

•Pollutant: Any substance that, in excess, is known to be harmful to desirable living organisms

•Oxygen-demanding waste (common organic waste)

•Pathogenic waste (pathogenic microbes)

•Nutrients•Petroleum (oil)•Toxic waste (chemicals, heavy metals, radioactive

waste)•Sediment•Thermal plumes

Oxygen-demanding waste

•Dead organic matter decomposed and consumed by aerobic bacteria, which need oxygen to live

•BOD (Biochemical Oxygen Demand) is the amount of oxygen used for bacterial decomposition

•High BOD, associated with a high level of decaying organic matter in water, reduces O for other healthy organisms

•Sources of oxygen-demanding waste: Natural processes, agricultural applications (33%), urban sewage, and runoff

Pathogenic microbes (need microscope to see them)

•Fecal coliform bacteria•Harmful risks (diseases and death ) of E. coli

which leads to disease and death in humans•Billions exposed to waterborne diseases,

especially in poor countries•Outbreaks do occur in developed countries, e.g.,

400,000 cases in Milwaukee WI, in 1993 of cryptosporidiosis (parisitic micro-organism)

•Epidemic risks of waterborne diseases during natural disasters (earthquake, flood, hurricane)

Nutrients Two important nutrients: N, P, from fertilizers,

detergent, and sewage-treatment products

Major problems caused by high concentrations of nutrients: Cultural eutrophication (well-fed by nutrient) - which leads to growth of algae bloom, triggering biological oxygen demand (BOD) problem

The algae covering the surface of water, block sunlight to plant below and consuming oxygen, killing the underlying plants.

Algae kill coral in tropical areas

Major sources for nutrients: Fertilizer, feedlots, and discharge from wastewater treatment plant

Land use Vs N concentrations in streams (in mg/l)

0

0.5

1

1.5

2

2.5

3

Forest Urban Agriculture

Land use Vs P concentrations in streams (in mg/l)

00.020.040.060.08

0.10.120.140.16

Forest Urban Agriculture

Oil

Major problems: Polluted water, ecosystem damage, interrupted socioeconomic conditions of a community

Major sources: Oil spills from tankers and pipelines, on- or offshore oil production, war (e.g., Persian Gulf War; 1989 Exxon Valdez)

Toxic Waste

•Hazardous chemicals, synthetic organic or inorganic compounds toxic to living things

•Serious pollution problems occur when these are introduced accidentally into surface/subsurface waters

– e.g., Love Canal, MTBE (methyl tertbutal ether; an oxygen additive to gasoline; leaked from gas stations to GW & SW)

– Groundwater with MTBE smells like fresh paint and is nauseating to some people. It may be carcinogenic!

Toxic Waste … Heavy Metals: Pb, Hg, Zn, Cd – often deposited at the

bottom of stream channels If deposited in floodplains will be incorporated into

plants, crops and animals Examples:

Mercury contamination of aquatic ecosystems; sourced: from volcanoes and erosion of natural mercury depositsBurning coal, incinerating waste, processing metals

Lead to e.g., lead or mercury contamination

Radioactive materials

Acid Mine Drainage

• Water with a high concentration of sulfuric acid (H2SO4)

– Sulfide minerals are associated with coal or metal mines and oxidize when then come in contact with water

Sediment pollution

Sand and smaller particles Polluted streams, lakes, reservoirs, even ocean

water

Major sources: Soil erosion, dust storms, floods, and mudflows

Greatest pollutant by volume

Thermal Pollution

•Artificial heating of waters, primarily be hot-water emission from industrial operations and power plants.

– Major sources: Hot-water discharge from industrial operations, power plants, abnormal ocean currents

•Heated water causes several problems: Heated water contains less O than cold water leads to adverse changes to the habitats of

organisms favors growth rate of undesirable organisms

Surface Water Pollution and Treatment

•Point sources of pollution Point sources are discrete, confined, and more

readily identifiable

Common sources: Landfills, discharge from wastewater treatment plants, discharge from

industries, power plants, storm water runoff, etc.

Identify sources, on-site treatment and mitigation, prevention

Surface Water Pollution and Treatment

•Nonpoint sources of pollution Nonpoint sources are diffused, intermittent,

and hard to specifically identify

Causes of nonpoint pollutions often regional, cumulative and compound

Waste Water Treatment

•Law: Used waste water must be treated

•Break the potential vicious cycle of waste water entering the general water cycle

•Tier treatment and reuse system Septic system—rural residential areas Water treatment plant for towns and urban cities Innovated ways for recycling and reclaiming

waste water New technologies for innovative waste water

treatment

Primary Wastewater Treatment

Removes about 30-40% of pollutantsA. Screening

Removes grit (stones, sand, large particles)

B. SedimentationRemaining particulate matter settles out to form a

mud called “sludge”

C. Discharge or go on to next stage of treatment

Secondary Treatment

• Removes 90% of pollutants

A. Waste water pumped through an Aeration tankAerobic bacteria digest more organics

B. Sedimentation TankMore sludge settles out

Sludge sent to a digesterAnerobic bacteria digest more organics

Methane produced

Secondary Treatment

C. Disinfection of wastewaterChlorineOzone

D. Discharge into surface waters or disposal wells or on to Advanced Treatment

Note: Secondary does NOT remove all nutrients, heavy metals, solvents and pesticides

Advanced Treatment

• Removes 95% of the pollutants• Targets nutrients, heavy metals, and synthetic

chemicals• Treated wastewater can be used as reclaimed water• Techniques vary:

– Filters– Chemical treatment

Wastewater TreatmentWastewater TreatmentMimics natural processes in wetlands

1) Remove solids2) Digest organic matter through

Aerobic bacteriaAnaerobic bacteria

3) Wetland plants trap and concentrate pollutants

4) Sediment provides natural filters5) Also provides a habitat

Where does the sludge go?Where does the sludge go?• 50-100 grams per person per day• Sludge handling/disposal accounts for 25-50% of the cost

– Sludge treatment:-

• Convert organics to a stable form• Remove liquid to reduce volume• Destroy harmful organisms• Produce useful byproducts

– soil

Groundwater Pollution and Treatment

•Saltwater intrusion More than half of the world’s population lives in or

near the coastal zones GW pollution from saltwater intrusion is not a

local isolated problem Causes major water supply problems in NY, FL, CA Case History: Long Island

GW Treatment

What is MTBE?(methyl tertiary butyl ether)

• A gas additive contaminating drinking water

History of MTBE?

• 1970 MTBE replaced lead in gasoline

• Clean Air Act of 1990 mandated MTBE in gas

• 4.5 billion gallons of MTBE have been used each year

• Discovered health risks in 1997

Health Risks of MTBE

• Dizziness

• Rashes

• Swelling

• Respiratory problems

• Diarrhea

• Caused cancer in research rats and mice

What are the concerns with MTBE?

• Soluble in water

• Degrades slowly

• Does not readily bind to soil particles

• Resists natural degradation

• travels quick and easy through ground water

Concentration of MTBE?

• For every 10 gallons of gas there is 1 gallon of MTBE

• 1 cup of MTBE contaminate a reservoir 360ft wide, 15ft deep holding 5 million gallons of water