Miller Chapter 19 Water Pollution

Pollution Defined Any chemical , biological, or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses.

Types and Sources of Water Pollution Infectious Agents Oxygen-Demanding Inorganic Chemicals Organic Chemicals Plant Nutrients Sediment Radioactive Thermal

CATAGORIES OF POLLUTANTS

I. Methods of Determining Water Quality A. Coliform Bacteria 0 colonies per 100ml for drinking water 200 colonies per 100ml for swimming

B. Biological Oxygen Demand (BOD) The amount of oxygen needed by decomposers to break down organic material over a 5-day period at 680F

Dissolved Oxygen (DO) Only a few species of fish can survive when the D.O. level drops below 4 ppm Water Quality Good 8-9 Do (ppm) at 20˚C Slightly polluted Moderately Heavily Gravely 6.7-8 4.5-6.7 Below 4.5 Below 4

C. Chemical Analysis Determine the levels of organic and inorganic pollution

D. Indicator Species Indicator species can be used to monitor water quality Ex: Mussels, Cattails, Insect larva Analyzed to measure the levels of various chemicals

II. Sources of Pollution A. Point Sources -Discharge from a specific location (pipe, ditch or sewer) -Easier to identify and regulate Ex: Factories, Sewage Treatment Plants, Mines, Thermal Outlets and Oil Tankers.

B. Non-Point Sources -Cannot be traced to a specific discharge -Difficult to identify and control Ex: Golf Courses, Agriculture, Homes

III.Water Pollution A. Rivers and Streams: -Most pollution in the form of: chemicals from industry or mines, malfunctioning sewage plants, Non-point runoff Naturally, streams and rivers can rebound: As long they are not overloaded with pollutants & Flow is not reduced

-The breakdown of degradable wastes by bacteria depletes dissolved oxygen -Reduces the population of oxygen requiring organisms. -Shown as an OXYGEN SAG CURVE

Time of distance downstream Clean Zone Decomposition Zone Septic Zone Recovery Zone (Trout, perch, bass, mayfly, stonefly) (carp, gar, Leeches) Fish absent, fungi, Sludge worms, bacteria (anaerobic) Normal clean water organisms 8 ppm Dissolved oxygen Biological oxygen demand Oxygen sag 2 ppm Concentration Types of organisms Time of distance downstream Direction of flow Point of waste or heat discharge Trash fish

-Recovery from oxygen depletion is based on the volume of the pollutant and … Stream Volume Flow Rate Temperature pH level

Stream and River Success Stories: -Water Pollution Control Laws of the 1970’s: Downstream withdraw of drinking water Reduce point-source pollution Increase # of treatment plants -Ohio’s Cuyahoga River (caught on fire in 1959 and 1969) Now used for boating and fishing

CLEAN WATER ACT and NON-POINT POLLUTION

Stream Pollution: The Bad News Accidental release of organic and inorganic chemicals Malfunctioning sewage treatment plants Non-point run-off of pesticides WORLD WIDE: 2/3 of streams monitored in China and India are severely polluted

B. Lakes -More vulnerable than streams due to… Stratified layers, Little flow, Low water volumes. Vulnerable to Biological Magnification & Cultural Eutrification: Human activities that increase the level of plant nutrients in lakes

Water 0.000002 ppm Herring gull 124 ppm Phytoplankton 0.0025 ppm Rainbow smelt 1.04 ppm Zooplankton 0.123 ppm Phytoplankton 0.0025 ppm Water 0.000002 ppm Herring gull 124 ppm Lake trout 4.83 ppm Herring gull eggs

The Terrible Twelve

Biological Magnification

Cultural Eutrophication Discharge of untreated municipal sewage (nitrates and phosphates) Nitrogen compounds produced by cars and factories Discharge of detergents ( phosphates) Natural runoff (nitrates and phosphates Manure runoff From feedlots (nitrates and Phosphates, ammonia) Discharge of treated municipal sewage (primary and secondary treatment: nitrates and phosphates) Runoff from streets, lawns, and construction lots (nitrates and phosphates) Lake ecosystem nutrient overload and breakdown of chemical cycling Dissolving of nitrogen oxides (from internal combustion engines and furnaces) Runoff and erosion (from from cultivation, mining, construction, and poor land use)

GREAT LAKES READ PAGES 483-484

C. Groundwater - Easily contaminated by everyday activities - Flows slowly so it cannot dilute/disperse contaminants - Small population of decomposers - Cold temps. Slow Rx that remove wastes

Contaminated Probability 10 to 20 percent Greater than 20 percent Not tested

- Up to 25% of usable, U.S. groundwater Extent of Contamination: - Up to 25% of usable, U.S. groundwater - 60% of liquid waste injected into deep underground wells - Pumping of water at coastlines causes contamination of drinking water by saltwater intrusion.

Unconfined freshwater aquifer Confined freshwater aquifer Waste lagoon, pond, or basin Mining site Pumping well Water pumping Sewer Cesspool, septic tank Hazardous waste injection Buried gasoline and solvent tanks Landfill Road salt Unconfined freshwater aquifer Confined freshwater aquifer Confined aquifer Discharge Leakage from faulty casing Groundwater Groundwater flow

IV. Preventing/Reducing Water Pollution Prevention: -Wiser use of fertilizer and pesticides -Plant buffer zones to control runoff -Banning Deep Injection Wells -Monitoring of waterways and aquifers -Clean Water Act (1977) -Water Quality Act (1987)

2. Reduction: - Septic Systems Septic tank Nonperforated Manhole (for Household wastewater Perforated pipe Distribution box (optional) Septic tank Manhole (for cleanout) Drain field Vent pipe Nonperforated Gravel or crushed stone

-Sewage Treatment 3 Levels of Purification A. Primary – mechanical treatment B. Secondary – biological treatment C. Advanced – Specialized chemical and physical processes to remove specific contaminants

Disposed of in landfill or ocean or applied to cropland, Raw sewage from sewers Bar screen Grit chamber Settling tank Aeration tank Chlorine disinfection tank Sludge Sludge digester Activated sludge Air pump (kills bacteria) To river, lake, or ocean Sludge drying bed Disposed of in landfill or ocean or applied to cropland, pasture, or rangeland Primary Secondary Fig. 19.15, p. 494

reservoirs, or industries Effluent from Secondary treatment Alum flocculation plus sediments Activated carbon Desalination (electrodialysis or reverse osmosis) Nitrate removal Specialized compound (DDT, etc.) 98% of suspended solids 90% of phosphates dissolved organics Most of dissolved salts Recycled to land for irrigation and fertilization To rivers, lakes, streams, oceans, reservoirs, or industries

What about the Sludge? Sewage sludge is a highly toxic mix of chemicals, infectious agents, and settle solids. -9% converted to compost -36% applied as fertilizer -55% dumped in landfills or burned

-Wastewater Gardens Sewage Treated water Wetland type plants (1) Raw sewage drains by gravity into the first pool and flows through a long perforated PVC pipe into a bed of limestone gravel. (3) Wastewater flows through another perforated pipe into a second pool, where the same process is repeated. (2) Microbes in the limestone gravel break down the sewage into chemicals, that can be absorbed by the plant roots, and the gravel absorbs phosphorus. (4) Treated water flowing from the second pool is nearly free of bacteria and plant nutrients. Treated water can be recycled for irrigation and flushing toilets. 45 centimeter layer of limestone gravel coated with decomposing bacteria First concrete pool Second concrete pool Sewage Wetland type plants Treated water

-Double Vault Systems and Dry Toilets

V. Drinking Water Quality In U.S. we have safe drinking water standards set by the Safe Drinking Water Act of 1974 Establishes Maximum Contamination Levels for any pollutants. Effects “city” water only, not wells. Purification of water done in various ways

-1/3 of all bottled water is contaminated with bacteria -International Bottled Water Association sets/maintains standards for bottled water.