Can you name the Top 10 Threats

to the Great Lakes?

#10 Water Withdrawals

Great Lakes water may be exported via pipe to arid southwestern states, or shipped to Asia or the Middle East, or bottled and shipped out of the region. The 8 states and one Canadian province have not established guidelines for export. (Lower Peninsula billboard)

#9 Polluted BeachesCombined sewer overflows bring

human and animal wastes that cause closed beaches.

#8 Air Pollution DepositionThe atmospheric pathway allows toxic substances to remain in the environment long after they have been produced or used. Since these pollutants do not break down easily, they can travel long distances in the air before depositing onto land or water.

#7 Pollution Hot SpotsSuperfund Sites & Areas of Concern

This dredge is scooping up decades worth of industrial pollution near Muskegon, MI. There are 43 total hot spots in US and Canada.

#6 Loss of Native Species(Clockwise: Coaster Brook Trout,

Diporia, Piping Plover, etc.)

#5 Point Source Pollution

Point source pollution comes directly from a discharge pipe, i.e. sewage from wastewater treatment plants, factories, chemical spills, etc.

#4 Cargo Ship ChannelsDredging, channel modifications, invasive species, etc.

#3 Shoreline Development & Loss of Coastal Wetlands

Wetlands are often called the kidneys of the Earth….filtering out contaminants.

#2 Nonpoint Source PollutionRunoff from rain and snowmelt carries contaminants from urban and agricultural sources. A well vegetated shoreline can filter out contaminants and prevent them from reaching the stream or lake.

#2 Nonpoint Source Pollution Examples

Contaminants on the ground are carried into storm drains...

“Dirty” snow melts and runs off…

Motor oil, gasoline, etc.

Trash…

Motor oil and gasoline run off…

Melting dirty snow and runoff….

New constructioncauses erosion….

#1 Invasive SpeciesThere are more than 160 aquatic species that have invaded the Great Lakes and changed them, almost always for the worse.

Sea Lamprey have been very destructive:• Sea lampreys attach to fish with a sucking disk and sharp teeth. • Feed on body fluids, often scarring and killing host fish. • Each sea lamprey can kill 40+ pounds fish. • Prey on all species of large Great Lakes fish: lake trout, salmon, steelhead, whitefish, chubs, burbot, walleye, catfish, sturgeon.

2007 State of the Lakes Ecosystem (SOLEC) Highlights Report 

The good news is:

• Over the past 30 years there has been a marked reduction in the levels of toxic chemicals in the air, water, flora, fauna and sediment.

• Great Lakes continue to be a good source for treated drinking water.

• In 2005, 74% of monitored Great Lakes beaches in the U.S. and Canada were open more than 95% of the swimming season. 

• Air quality is improving, although there still regions that continue to have ozone and smog problems.

• Significant natural reproduction of lake trout is occurring in lakes Huron and Superior.

2007 State of the Lakes Ecosystem (SOLEC) Highlights Report

The bad news is:

• New chemicals of concern, such as pharmaceutical and personal care products are being detected in rivers and lakes more frequently.

• Still need sport fish consumption advisories for mercury, PCBs, etc.

• Non-native species (quagga mussels, spiny water fleas, etc. ) continue to invade the Great Lakes and impair the food web.

• Declines in the duration and extent of ice cover on the Great Lakes and declining lake levels due to evaporation during the winter are expected to continue.

• Aquatic habitats on the coasts continue to deteriorate due to development, shoreline hardening and non-native species, resulting in habitat loss for fish, birds, and amphibians, and reduced water quality.

See State of the Great Lakes 2007 Highlights Report: www.epa.gov/glnpo/solec.

What Can We Do?

• Inventory stream and lake shorelines.

• Take actions to protect Great Lakes’ watersheds and the streams & rivers that feed them.

• Make personal choices that protect the Great Lakes.

• Support measures to restore the Great Lakes---research, funding, laws, etc.