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Glossary of technical terms
    that appear in the LaMPs

Acronyms | Words and definitions

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Science Advisory Board (SAB)

A binational advisory group that provides advice on the adequacy of Great Lakes science and research to the International Joint Commission and the Water Quality Board. The board is responsible for developing recommendations on all matters related to research and the development of scientific knowledge pertinent to the identification, evaluation, and resolution of current and anticipated problems related to Great Lakes water quality.

Scientific and Natural Areas (SNA)

These are areas set aside to preserve the ecological diversity of Minnesota's natural heritage. They include landforms, fossil remains, plant and animal communities, rare and endangered species or other biotic features and geologic formations. The areas are preserved for scientific study and public edification as components of a healthy environment. The program is administered by the MN DNR, Division of Fish and Wildlife.

Sea Lamprey

An exotic, eel-like animal that attaches to fish with a sucking disk and sharp teeth. A native of the Atlantic Ocean, the lamprey made its way into all the Great Lakes following the opening of the Welland Canal in 1829 and its deepening in the 1900ís. By the 1930ís, sea lamprey were found in all of the Great Lakes. During the 1940ís and 1950ís, lamprey caused the collapse of lake trout, whitefish, and chub populations in all the Great Lakes with the exception of Lake Superior. It has been estimated that one sea lamprey can kill up to 40 pounds of lake trout during its lifespan. See also "Sea Lamprey Control Program."

Sea Lamprey Control Program

The U.S. Fish and Wildlife Service and the Department of Fisheries and Oceans in Canada work together, under the direction of the Great Lakes Fishery Commission, to minimize sea lamprey populations in the Great Lakes. Lamprey are controlled by applying a selective toxicant, TFM, to streams during the lampreyís most vulnerable life stage. Other control techniques include barriers, pheromone release, and sterilization of male lamprey.

Seaway Port Authority of Duluth

The Authority, consisting of seven members representing state, county, and city (Duluth) interests, promotes growth of international and domestic maritime commerce for Minnesotas World Port, and strives to strengthen the financial condition of the Port while enhancing the regional economy through industrial development and construction of port facilities. The Authority co-sponsored, along with the Lake Carriers Association, the Voluntary Ballast Water Exchange Plan for the Control of Ruffe in Lake Superior.

Secchi disk

A black and white patterned disk lowered into the water column to measure water clarity. See also "Secchi Disk Depth (SDD)."

Secchi Disk Depth (SDD)

An estimate of the transparency of a lake, obtained by lowering a small (20 cm) disk into the water until it is no longer visible and noting the depth at which it disappears from view. Oligotrophic lakes are typically more transparent (and have a greater Secchi depth) than more productive, or eutrophic lakes. See also "Secchi Disk."

Secondary Treatment

The second step in most publicly-owned treatment systems, where bacteria consume the organic parts of the waste.

Section 10

Refers to Section 10 of the federal Rivers and Harbors Act of 1899.

Section 118

A term used to refer to Section 118 of the federal Clean Water Act that identifies program requirements for the Great Lakes.

Section 305 (b)

The term refers to Section 305 (b) of the federal Clean Water Act, which requires a report on the status of fishable, swimmable waters. The states submit a biennial report to the EPA, which compiles the reports into a report to Congress.

Section 319

A term used to refer to Section 319 of the federal Clean Water Act that identifies the program requirement for nonpoint source management programs.

Section 401

A term used to refer to Section 401 of the federal Clean Water Act which requires water quality certification by the appropriate state agency, for example, the Minnesota Pollution Control Agency. Under Section 401, no federal permit to discharge pollutants into the waters of the U.S. is valid unless the state where the discharge occurs grants or waives its right to certify that the permit will not violate the state water quality standards. A federal agency cannot issue a permit when the state has denied water quality certification.

Section 402

A term used to refer to Section 402 of the federal Clean Water Act that identifies permit requirements for point source discharges, known as the National Pollutant Discharge Elimination System.

Section 404

A term used to refer to Section 404 of the federal Clean Water Act that outlines permit requirements for dredging and other filling activities in waters of the U.S. This is the primary federal law that regulates activities affecting wetlands. The Section 404 program is administered by the Army Corps of Engineers in accordance with the EPA.

Section 6217

A federal regulation that is a part of the Coastal Zone Act Reauthorization Amendments of 1990 entitled, Protecting Coastal Waters. This provision requires states with Coastal Zone Management Programs that have received federal approval under Section 306 of the Coastal Zone Management Act, to develop and implement Coastal Nonpoint Pollution Control Programs. These programs are to be used to control sources of nonpoint pollution which impact coastal water quality. See also "Coastal Zone Act Reauthorization Amendments of 1990" and "Coastal Zone Management Act."


Soil particles suspended in and carried by water as a result of erosion. The particles are deposited in areas where the water flow is slowed such as in harbors, wetlands, and lakes. This process is referred to as sedimentation.


Seiches are lakewide displacements of water that are wind-induced. Water pushed by the wind can pile up on shore causing noticeable increases in water depth. When the wind is reduced the water mass continues to slosh back and forth like water in a bathtub.


Selenium is a naturally occurring element found in sedimentary rock formations, generally combined with sulfide minerals or silver, copper, lead, or nickel. It is released to the environment through natural processes or by such anthropogenic sources as coal combustion, petroleum fuel combustion, and smelting and efining of metals. There are 271 metals industry-related facilities in the Lake Michigan basin that may serve as sources of selenium.

Sentinel species

A species used as an indicator of overall environmental conditions, particularly contaminants. For example, mayflies (hexagenia), and bald eagles.


A term used in wetlands regulations to define a process that involves avoiding, minimizing, and mitigating impacts.

Sewage Treatment Plant

A system that treats (which can include recycling and reclamation) municipal sewage or industrial wastes of a liquid nature. Large facilities are generally owned and operated by local governments.

Shoreland Management Program

A Minnesota program administered by a local government unit that meets minimum standards and criteria for the subdivision, use, and development of the shorelands of public waters.


Refers to Minnesota lands located 1000 feet from the ordinary high water level of a lake, pond, or flowage, and 300 feet from a river, stream, or the landward extent of floodplains.

Sigurd Olson Environmental Institute

A regional, private, non-profit organization of Northland College in Ashland, Wisconsin. Its mission is to protect environmental quality in the greater Lake Superior region and to build a future that is ecologically, socially, and economically sustainable.

Site-Specific Criteria

Water quality criteria that have been developed to be specifically appropriate to the water quality characteristics and/or species composition at a particular location. Also see "Great Lakes Initiative" and "National Pollutant Discharge Elimination System (NPDES)."

Soil and Water Conservation Districts (SWCDs)

Local county units of government that assist landowners with implementation of soil and water conservation measures and practices. Also see "Board of Water and Soil Resources."

Soluble reactive phosphorus

The part of total phosphorus that bioavailable.

Source Reduction

A term that means reducing pollution at its source. It includes management systems, technologies, and other practices which reduce or eliminate the amount of any hazardous substance, pollutant, or contaminant entering any waste stream or otherwise released into the environment prior to recycling, treatment, or disposal. The term includes equipment or technology modifications, reformulation or redesign of products, substitution of raw materials, and improvements in housekeeping, maintenance, training, or inventory control. Often referred to as pollution prevention. Also see "Pollution Prevention," "Pollution Prevention (P2) Strategy," "Clean Water Act," and "Great Lakes Initiative."

Special Designation

As part of the Binational Program to Restore and Protect the Lake Superior Basin, governments are encouraged to make special designations which: favor zero discharge of human made toxins and protect and enhance the unique character and pristine nature of the lake basin. The U.S. policy on special designation includes enhanced anti-degradation approaches (including best available technology) for new or proposed expansions to facilities.

St. Louis River Management Plan

A local management plan developed by the St. Louis River Board to provide adequate protection to the Whiteface, Cloquet, and St. Louis rivers ecosystems in the areas of land use, forestry management, and land acquisition. Once implemented, the plan will result in increased lot sizes, a no-cut zone along the river corridor, mandated forestry management plans, and public purchase of 22,000 acres of river front land. Also known as the St. Louis, Cloquet, Whiteface Corridor Management Plan.

St. Louis River Remedial Action Plan (St. Louis River RAP)

A two-state (MN and WI) group representing industry, environmental groups, academic institutions, government, researchers, and community leaders coordinated by the MPCA and WDNR. The goal is to develop a plan to combat pollution sources and to protect natural areas on the St. Louis River, an Area of Concern and the largest U.S. tributary to Lake Superior. See also "Remedial Action Plan."

St. Louis Riverwatch

A citizen-based water quality monitoring, outreach, and education program administered by the MPCA. Students and teachers from the communities along the river conduct water chemistry tests and survey the benthic invertebrate community as well as monitor frog populations and sediment toxicity. See also "River Watch."


A legally enforceable limit for a substance or an agent intended to protect human health or the environment. Exceeding the standard could result in unacceptable harm. Also see "Water quality standard."

State Implementation Plan (SIP)

A state plan that sets out the process for complying with the Clean Air Act requirements. If approved by the EPA it will give the state the authority to run the federal clean air program for the state. Also see "Clean Air Act."

State of the Lake Superior Basin Reporting Series (SOTLSBRS)

A series of reports prepared by the Superior Work Group that will communicate progress on the Lake Superior Binational Program. When completed, the series will consist of 5 volumes:
Vol I: Introduction to the Basin, Its Economy, and Its Inhabitants;
Vol II: Lakewide Management Plan (Stages I-IV);
Vol III: Lakewide Management Plan for Nonchemical Stressors;
Vol IV: Ecosystem Principals and Objectives for Lake Superior; and
Vol V: Comprehensive Management Plan to Protect the Lake Superior Ecosystem (an amalgamation of volumes I-IV).

State of the Lakes Ecosystem Conference (SOLEC)

A conference sponsored by Environment Canada and EPA, held every two years to review and make available information on the state of the chemical, physical, and biological integrity of the Great Lakes basin ecosystem. A major purpose of the conference is to cooperate in implementing the Great Lakes Water Quality Agreement by supporting better decision-making through improved availability of information on the condition of the living components of the system and the stresses which affect them. Working papers are prepared as background for the conference.


An enactment of the legislative body of a government that is formally expressed and documented as a law.

Storm Sewers

The underground infrastructure designed to collect storm runoff from urban areas which is typically not treated by sewage treatment facilities before being discharged into nearby surface waters. Storm sewer runoff has been found to be a major contributor to nonpoint source pollution in the Great Lakes.

Storm Water

Rainwater runoff, snow melt runoff, surface water runoff, and discharges that are collected by storm sewers. Also see "National Pollutant Discharge Elimination System (NPDES)."

Strategic Great Lakes Fisheries Management Plan (SGLFMP)

The Strategic Great Lakes Fisheries Management Plan was developed by fisheries managers at the federal, state, and tribal levels through the Great Lakes Fishery Commission. The Management Plan defines the common goals for management of the Great Lakes fisheries, recognizes the positive developments in the fisheries, and presents remaining problems.


Any chemical, physical, or biological entity that can induce adverse effects on individuals, populations, communities, or ecosystems and be a cause of beneficial use impairments. Examples of stressors include: pathogens, fragmentation, and destruction of terrestrial and aquatic habitats, exotic nuisance species, and uncontrolled runoff and erosion.

Sulfur Dioxide (SO2)

A chemical compound that when emitted to the atmosphere is considered to be a major component of acid rain. One of the criteria pollutants regulated by the 1990 Clean Air Act Amendments, SO2 is emitted mainly by anthropogenic sources. Sources include industrial point sources, such as coal fired electric utilities.


A process to restrict, phase out, and eventually ban the manufacture, generation, use, storage, discharge, and disposal of a persistent toxic substance.


See "Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)."

Superfund Amendment Reauthorization Act (SARA)

See "Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)."

Superior Lakewatch

A binational organization coordinated by the Lake Superior Center, the Ontario Ministry of Environment and Energy, and the Sea Grant Offices of Michigan, Wisconsin, and Minnesota that offers volunteers the opportunity to help in monitoring the water quality of Lake Superior by measuring Secchi disk depth throughout the lake.

Superior Workgroup

A binational organization that assembles technical and scientific professionals from each of the six jurisdictions (U.S. and Canada) and key national agencies surrounding Lake Superior to coordinate Binational Program implementation.

Surface Water

All water above the surface of the ground including, but not limited to lakes, ponds, reservoirs, artificial impoundments, streams, rivers, springs, seeps, and wetlands.

Sustainable Development

Sustainable development is the process of economic development to meet the needs of the present without compromising the ability of future generations to meet their own needs.

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