Environment

WATER POLLUTION

Lecture 16

HUMANS AND MUCH OF LIFE DEPENDS ON WATER

- ABUNDANT BUT FINITE SUPPLY

- CONTINUALLY RECYCLED AND PURIFIED

WATER POLLUTION

- CHANGE IN WATER WITH HARM TO HUMANS OR OTHER ORGANISMS

MAJOR THREAT TO HUMAN HEALTH

SPREAD OF DISEASE

TOXIC MATERIALS

WHY SHOULD YOU CARE ABOUT WATER POLLUTION?

THE EARTH’S WATER SUPPLY

WATER COVERS ABOUT 73% EARTH SURFACE

- 0.024% OF TOTAL WATER AVAILABLE

- REMAINDER SALTY, TOO DEEP OR FROZEN

- 30% AVAILABLE FRESHWATER IN AQUIFERS

- HALF WORLD DRINKING WATER

- 25% WATER USED IN U.S.

 WATER NOT EVENLY DISTRIBUTED

MANY DON'T HAVE ACCESS TO ENOUGH

WATER HABITAT FOR MANY ORGANISMS

- AQUATIC LIFE ZONES

- MARINE AQUATIC SYSTEMS

- - FRESHWATER AQUATIC SYSTEMS

 LAYERS OF WATER DIFFERENT PROPERTIES

- UPPER WARMER WITH LIGHT

- MIDDLE SOME LIGHT, COLDER

- DEEPER DARK, COLD

- DISSOLVED OXYGEN

WATER AS HABITAT

MARINE AQUATIC SYSTEMS

LARGEST AQUATIC SYSTEM

 FOUR OCEANS

- PACIFIC (LARGEST)

- ATLANTIC

- ARCTIC

- INDIAN

MARINE ZONES

- COASTAL ZONE

- OPEN SEA

- OCEAN BOTTOM

FRESHWATER AQUATIC SYSTEMS

TWO TYPES

STANDING BODIES

- LAKES, PONDS

- INLAND WETLANDS

- HIGH BIODIVERSITY

- ABSORB WATER

- MANY FORMED BY GLACIERS

- CLASSIFIED BY AMOUNTS OF NUTRIENTS

• EUTROPHIC OR OLIGOTROPHIC

FRESHWATER AQUATIC SYSTEMS

FLOWING SYSTEMS

- RIVERS AND STREAMS

- WATERSHED OR DRAINAGE BASIN

- SOURCE ZONE

- TRANSITION ZONE

- FLOODPLAIN ZONE

WHAT ARE THE PROBLEMS? HUMAN IMPACTS ON NATURAL CYCLES

THREE MAJOR IMPACTS

1. FRESHWATER TAKEN FROM STREAMS, LAKES, AND AQUIFERS

- OFTEN FASTER THAN REPLACEMENT

2. CLEAR LAND AND MAKE IMPERMEABLE TO WATER

- FASTER RUNOFF

- SLOWER RECHARGE OF AQUIFERS

3. DRAINING AND FILLING WETLANDS

- NATURAL "SPONGES"

- RUNOFF INCREASES

 SUBSTANCES DUMPED INTO WATER CAN REDUCE USEFULNESS

- DRINKING, FISHING, SWIMMING, IRRIGATING & OTHER USES OF WATER

POLLUTANT SOURCE

- POINT

- NONPOINT

SOURCES OF WATER POLLUTION

POLLUTION OF RIVERS LAKES

 HALF OF WORLD’S 500 RIVERS HEAVILY POLLUTED

- UNTREATED SEWAGE

- INDUSTRIAL WASTE

 DEVELOPING COUNTRIES

• CHINA'S RIVERS

-1/2 CAN'T BE USED FOR ANY PURPOSE

• INDIA’S RIVERS

-275 OUT OF 445 SEVERELY POLLUTED

 WATER POLLUTION OFTEN REVERSIBLE

- REMOVE SOURCE OF POLLUTION

- BIODEGRADABLE POLLUTANTS

- NONBIODEGRADABLE

POLLUTION OF LAKES

LAKES AND RESERVOIRS LESS EFFECTIVE AT DILUTING POLLUTANTS THAN STREAMS

-STRATIFIED LAYERS WITH LITTLE VERTICAL MIXING

-LITTLE OR NO WATER FLOW

-CAN TAKE UP TO 100 YEARS TO FLUSH AND CHANGE THE WATER IN A LAKE

-BIOLOGICAL MAGNIFICATION OF POLLUTANTS

OCEAN POLLUTION

37% WORLD 40% U.S. LIVE NEAR SEA

- HUMAN IMPACTS ON OCEAN WATERS

- 80-90% LESS DEVELOPED COUNTRIES SEWAGE DIRECTLY DUMPED

 EXCESS NUTRIENTS

- MICROBES

- OXYGEN-DEMANDING WASTES

- OXYGEN DEPLETED ZONES

OCEAN POLLUTION

 EXCESS NUTRIENTS - OXYGEN DEPLETED “DEAD” ZONES - MISSISSIPPI RIVER DISCHARGE

 CORAL REEFS VERY SUSCEPTIBLE - SLOW GROWTH - FAIRLY SHALLOW WATER

 OIL POLLUTION - LARGE AND SMALL SPILLS - RUNOFF FROM CITIES

 PLASTIC - GREAT PACIFIC GARBAGE PATCH

GROUNDWATER POLLUTION

MUCH OF WORLD DEPENDS ON GROUNDWATER

- DRINKING AND IRRIGATION WATER

POLLUTANTS

- FERTILIZERS, PESTICIDES

- GASOLINE, OIL, PAINT THINNERS

- SEPTIC SYSTEMS

- WASTE PONDS

- UNDERGROUND STORAGE TANKS

WHAT CAN BE DONE? CLEAN-UP VERSUS PREVENTION

TWO WAYS CLEANUP OR PREVENTION

- PREVENTION BETTER

- ONLY 15% OF OIL SPILLS RECOVERED

- DAMAGE BEFORE CLEANUP

- BETTER REGULATIONS

- GROUNDWATER IS PARTICULARLY HARD TO CLEAN UP

LEGAL MEASURES

WATER POLLUTION MAJOR POLITICAL PROBLEM

- U.S. CLEAN WATER ACT

• PERMISSIBLE POLLUTANT LEVELS

- PERCENT WASTEWATER TREATMENT

• INCREASED FROM 33% TO 75%

- SAFE STREAMS INCREASED 33-60%

- NATIONAL AND INTERNATIONAL LAWS

- OIL TANKERS

TECHNOLOGICAL SOLUTIONS

NONPOINT-SOURCE POLLUTION DIFFICULT

- DIFFICULT TO ENFORCE A LAW

• IDENTIFICATION OF RESPONSIBLE PARTY HARD

• LARGE AREA

- LANDSCAPE APPROACH

• KEEP CROPLAND VEGETATED

• FENCE OUT LIVESTOCK

• WISE USE OF FERTILIZERS

TECHNOLOGICAL SOLUTIONS

WASTEWATER OR SEWAGE TREATMENT PLANTS

• PRIMARY SEWAGE TREATMENT • PHYSICAL PROCESS

• SECONDARY SEWAGE TREATMENT • BIOLOGICAL PROCESS USING BACTERIA

• TERTIARY OR ADVANCE SEWAGE TREATMENT • SPECIAL FILTERING PROCESSES

• BLEACHING AND DISINFECTION

ECONOMIC AND POLITICAL SOLUTIONS

LEGAL REQUIREMENTS OFTEN SPUR TECHNOLOGY

- DISCHARGE TRADING POLICY

- PERMITS FOR DISCHARGE INTO WATERWAYS

- ABILITY TO POLLUTE CAN BE SOLD AND TRADED

- CREATES A MARKET

- CAPS LOWERED EVERY FEW YEARS

WHAT WOULD YOU DO?

Mindful of water use

• use only needed water

• no dumping of harmful substances

• no yard waste in stream

Personal choices

• buy from companies with good policies

• only activities that minimize pollution

• use manure or compost, not fertilizers

Social activity

• talk about water pollution

• support politicians with good policies

• emphasize preventing pollution