Muskegon River Mega Model





Acre-foot (acre-ft)- the volume of water required to cover one acre of land (43,560 square feet) to a depth of one foot. Equal to 325,851 gallons or 1,233 cubic meters.

Aesthetics - the pleasurable sensations, mental and physical, which humans may experience as a result of certain environmental resources.

Agricultural Land Use - can be broadly defined as land that is used primarily for the production of farm commodities.

Algae (also; algal) - Simple rootless plants that grow in sunlit waters in proportion to the amount of available nutrients. They can affect water quality adversely by lowering the dissolved oxygen in the water. They are food for fish and small aquatic animals.

Ambiguities - has more than one meaning.

Anomaly - a deviation, irregularity, or an unexpected result.

Aquatic - in water; not terrestrial.

Aquatic Insects - are those that spend some part of their life-cycle closely associated with water, either living beneath the surface or skimming along on top of the water. Aquatic insects are an important source of food for fish, and can also be an indicator of water quality.

Aquatic Plants - also called hydrophytic plants or hydrophytes, are plants that have adapted to living in or on aquatic environments.

Aquifer - A water-bearing layer (or several layers) of rock or sediment capable of yielding supplies of water; typically is unconsolidated deposits or sandstone, limestone or granite; and can be classified as confined or unconfined.

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Backcasting - is the process defining a desirable future and then working backwards to identify policies and programs that will connect the future to the present.

Backwater - also known as a reservoir or impoundment.

Bank Armoring - also known as bank stabilization.

Bank Stabilization - adding materials to a streambank to prevent erosion.

Baseflow - sustained flow of a stream in the absence of direct runoff. It includes natural and human-induced streamflows. Natural base flow is sustained largely by groundwater discharges.

Basin - also known as a catchment, a drainage basin, or a watershed.

Bedload - material transported along the bottom of a stream by rolling or sliding, in contrast to material carried in suspension.

Benthic - an organism that feeds on the sediment at the bottom of a water body such as an ocean, lake, or river.

Biodiversity - the variety of organisms found within a specified geographic region.

Biofuel - a fuel produced from dry organic matter or combustible oils produced by plants. Examples of biofuel include alcohol (from fermented sugar), black liquor from the paper manufacturing process, wood, and soybean oil.

Biological Integrity - the ability to support and maintain balanced, integrated, functionality in the natural habitat of a given region.

Biomass - all of the living material in a given area; often refers to vegetation.

Bog - shrubby peatland dominated by shrubs, sedges, and peat moss and usually having a saturated water regime. Bogs have a high water table maintained directly by rain and snow. Bogs are characterized by acid-loving vegetation, and are often typified by the dense surface cover of aquatic moss.

Boon - something that functions as a blessing or benefit to somebody.

Boulder - a rock fragment with a diameter of more than 256 mm (about the size of a volleyball). A boulder is one size larger than a cobble.

Business As Usual (BAU) - a future landscapes that assume the average rate of urban and forest growth observed from 1978 to 1998 will continue into the future.

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Carbon (C) - a very common element in the universe. It is the basic chemical building block of life as we know it.

Carbon Dioxide (CO2) - a naturally occurring gas, and also a by-product of burning fossil fuels and biomass, as well as land-use changes and other industrial processes.

Catchment - also known as a basin, drainage basin, or watershed.

Channel- an area that contains continuously or periodically flowing water that is confined by banks and a stream bed.

Channel Stabilization - erosion prevention and stabilization of velocity distribution in a channel using jetties, drops, revetments, vegetation, and other measures.

Chemistry - the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions.

Clay - sedimentary material composed of fragments with a diameter of less than 1/256 mm. Clay particles are smaller than silt particles.

Climate - The composite or generally prevailing weather conditions of a region, throughout the year, averaged over a series of years.

Climate Change (also; global warming) - Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). Climate change may result from: 1: natural factors, such as changes in the sun's intensity or slow changes in the Earth's orbit around the sun; 2: natural processes within the climate system (e.g. changes in ocean circulation); 3: human activities that change the atmosphere's composition (e.g. through burning fossil fuels) and the land surface (e.g. deforestation, reforestation, urbanization, desertification, etc.).

Coast (also; Coastal Zone) - Lands and waters adjacent to the coast that exert an influence on the uses of the sea, lake, or river; and its ecology, or whose uses and ecology are affected by the sea.

Cobble - a rock fragment with a diameter between 6.4 cm (about the size of a tennis ball) and 25.67 cm (about the size of a volleyball). Cobbles are larger than pebbles but smaller than boulders.

Coldwater Fish - a fish that requires relatively cool water for survival. While the optimum temperature varies by species, most are found in water where temperatures are 20°C (68°F) or less.

Conductivity - a measure of the ability of a solution to carry an electrical current, and is a measure of water purity. However, conductivity is only a quantitative measurement: it responds to all ionic content and cannot distinguish particular conductive materials in the presence of others.

Confined Feeding (Area) - agricultural enterprises consisting of a lot of facility where animals are stabled or confined and fed of maintained.

Coniferous - cone bearing trees. These trees have needles instead of leaves. Examples of conifers are fir, pine and spruce trees.

Corridor - a natural or restored pathway for a population of organisms to use in order to breed and/or remain contiguous.

Crown - the top of a tree or group of trees; the leaves and living branches of a tree.

Crown Cover - the area covered by the crowns of trees growing closely together, often expressed as a percentage for the combined crown cover of trees in a defined area.

Cubic feet per second (cfs or ft2/s)- a rate of the flow, in streams and rivers, for example. It is equal to a volume of water one foot high and one foot wide flowing a distance of one foot in one second. One "cfs" is equal to 7.48 gallons of water flowing each second.

Cubic meter per second (cms or m2/s) - a rate of the flow, in streams and rivers, for example. It is equal to a volume of water one meter high and one meter wide flowing a distance of one foot in one second. One “cms” is equal to 35.31467 cfs.

Culvert - a metal, concrete, or plastic pipe through which water is carried.

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Database - an organized collection of records containing data for a specific purpose that can be searched and retrieved.

Dam - is a barrier (wall) of earth, concrete or rock. A dam is built across a river to restrict the flow of water. Currently there are over 100 dams in the Muskegon River Watershed.

Deciduous - Deciduous plants or trees lose their leaves for part of the year (i.e. winter). Examples of deciduous trees include maple, birch, oak and aspen.

Degree-Day - a rough measure used to estimate the amount of heating required in a given area; is defined as the difference between the mean daily temperature and 65 degrees Fahrenheit. Degree-days are also calculated to estimate cooling requirements.

Deleterious - having a harmful effect.

Deposition - settlement of materials out of the water column and onto the stream bottom.

Discharge - the volume of water that passes a given location within a given period of time. Usually expressed in cubic feet per second.

Dissolved Total Inorganic Nitrogen (tin) - the total amount of dissolved inorganic nitrogen (nitrogen compounds not containing carbon molecules) in the form of ammonia, ammonium, nitrates, nitrites, nitrogen gas, or nitrogen oxides.

Dominant Discharge (DD) - the streamflow that is responsible for transporting the majority of the sediment and is responsible for creating or maintaining the characteristic size and shape of the channel.

Drainage Basin - also known as a basin, catchment, or watershed.

Drawdown - amount of water used from a reservoir.

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Ecology - the environment as it relates to living organisms.

Ecosystem - is a natural unit consisting of all plants, animals and micro-organisms (biotic factors) in an area functioning together with all of the non-living physical (abiotic factors) of the environment.

Ecosystem Degradation - the deterioration of the environment through depletion of resources such as air, water and soil; the destruction of ecosystems and the extinction of wildlife.

Ecosystem(s) Management - the process of sustaining ecosystem integrity through partnerships and interdisciplinary teamwork. Ecosystem-based management focuses on three interacting dimensions: the economy, the social community, and the environment. Ecosystem-based management seeks to sustain ecological health while meeting economic needs and human uses.

Erosion - the wearing away of land surface by wind or water, intensified by land-clearing practices related to farming, residential or industrial development, road building, or logging.

Eutrophication - the slow aging process during which a lake, estuary, or bay evolves into a bog or marsh and eventually disappears. During the later stages of eutrophication the water body is choked by abundant plant life due to higher levels of nutritive compounds such as nitrogen and phosphorus. Human activities can accelerate the process.

Evaporation (Evap.) - the process of liquid water becoming water vapor, including vaporization from water surfaces, land surfaces, and snow fields, but not from leaf surfaces.

Evapotranspiration (ET) - the sum of evaporation and transpiration.

Exfiltration - the removal of water from the soil at the ground surface, together with the associated unsaturated upward flow.

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Farmland Preservation (FLP) Scenario - a scenario developed by MWRP researchers where the conversion of existing farmland to shrubs; and then forest is not allowed. Furthermore, urbanization continues at the expense of agricultural lands, either at a reduced rate or the observed historical rate. For more details on the FLP scenario, read Bulletin Volume 2: Managing the Land.

Fishery (also; fisheries) - the combination of fish and fishers in a region, the latter fishing for similar or the same species with similar or the same gear types.

Flood - an overflow of water onto lands that are used or usable by man and not normally covered by water. Floods have two essential characteristics: The inundation of land is temporary; and the land is adjacent to and inundated by overflow from a river, stream, lake, or ocean.

Floodplain - a strip of relatively flat and normally dry land alongside a stream, river, or lake that is covered by water during a flood.

Flow (also; Flow Rate) - the rate, expressed in gallons -or liters-per-hour, at which a fluid passes a certain point (or escapes) e.g. the discharge of water from a river mouth.

Forest - an area that has a high density of trees (deciduous and/or coniferous), and must have a crown cover of at least 25%.

Fragmentation - usually refers to habitat fragmentation, which means to divide habitat into smaller pieces. Fragmentation is often the result of clearing land for cities, roads, and agriculture.

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Geographic Information Systems (GIS) - integrated collection of computer software and data used to view and manage information about geographic places, analyze spatial relationships, and model spatial processes. A GIS provides a framework for gathering and organizing spatial data and related information so that it can be displayed and analyzed.

Geology - the make-up of the earth’s surface. Also, the branch of science that studies the make-up of the earth's surface.

Georeferencing (also; Georeferenced) - aligning geographic data to a known coordinate system so it can be viewed, queried, and analyzed with other geographic data.

Grassland - are fairly flat areas of grass, generally open and continuous.

Gravel - a loose mixture of sediment consisting mainly of rounded particles with a diameter greater than 2 millimeters.

Great Lakes (GL) - a chain of freshwater lakes located in eastern North America, on the Canada/United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth.

Greenhouse Gas - a gas, such as carbon dioxide or methane, which contributes to potential climate change.

Groundwater - water that flows or seeps downward and saturates soil or rock, supplying springs and wells. The upper surface of the saturate zone is called the water table. Also can be water stored underground in rock crevices and in the pores of geologic materials that make up the Earth's crust.

Growing Season - the part of the year when temperatures and moisture are favorable for vegetation growth.

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Habitat - (Latin for "it inhabits") is an ecological or environmental area that is inhabited by a particular animal or plant species.

Habitat Destruction - the process in which natural habitat is rendered functionally unable to support the species originally present. In this process, plants and animals which previously used the site are displaced or destroyed, reducing biodiversity.

Headwaters - the source and upper reaches of a stream; also may be thought of as any and all parts of a river basin except the mainstream river and main tributaries.

HEC- HMS (Hydrologic Engineering Center - Hydrologic Modeling System) - is designed to simulate the precipitation-runoff processes of dendritic watershed systems.

HEC- RAS (Hydrologic Engineering Center - River Analysis System) - is a model that performs one-dimensional steady flow, unsteady flow, sediment transport/mobile bed computations, and water temperature modeling.

Hydralics (also; Hydrologic Cycle) - the cyclic transfer of water vapor from the Earth's surface via evapotranspiration into the atmosphere, from the atmosphere via precipitation back to earth, and through runoff into streams, rivers, and lakes, and ultimately into the oceans.

Hydroelectric - the use of water in the generation of electricity at plants where the turbine generators are driven by falling water.

Hydrology (also; hydrologics) - is the science of the waters of the earth, their occurrence, distribution, and circulation; their physical and chemical properties; and their reaction with the environment, including living beings. Hydrology also includes the study of the movement and storage of water in the natural and disturbed environment and the condition of the aquatic environment at some specified time and place.

Hypothesis - a provisional explanation for observations subject to continual testing and modification. If well supported by evidence, hypotheses are then generally called theories.

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Impoundment - also known as a reservoir of backwater.

Infiltration - flow of water from the land surface into the subsurface.

Infrastructure - water and sewer lines, roads, transit infrastructure, schools and other facilities needed to support development.

Integrated Landscape Hydrology Model (ILHM) - a model that simulates all major surface and near-surface hydrologic processes including ET, snowmelt, groundwater recharge, and stream discharge.

Intergovernmental Panel on Climate Change (IPCC) - is a scientific intergovernmental body tasked to evaluate the risk of climate change caused by human activity. The panel was established in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), two organizations of the United Nations.

Inundate - to cover with water.

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Kilowatt - a standard measure of demand for power or capacity.

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Lake - inland water bodies that have little or no flow. Lakes usually occur at the end of large river systems, although some exist as a result of groundwater breaking the surface.

Lake Effect - the effect of any lake in modifying the weather about its shore and for some distance downwind.

Lake Michigan - Lake Michigan is the only one of the five Great Lakes wholly within the U.S. border. It is bounded by the states of Michigan, Indiana, Illinois, and Wisconsin. It is connected with and flows into Lake Huron through the Straits of Mackinac.

Landscape - the traits, patterns, and structure of a specific geographic area, including its biological composition, its physical environment, and its anthropogenic or social patterns. An area where interacting ecosystems are grouped and repeated in similar form.

Land Transformation Model (LMT) - is a spatial model that simulates future change in land use and land cover based on inputs of historical land use and land cover data.

Land Cover - the natural vegetation that occurs on a piece of land.  Examples of land cover include different types of forests, marshes, and bodies of water such as lakes.

Land Management (LM) - is defined as the process of managing the use and development (in both urban and suburban settings) of land resources in a sustainable way.

Land Use - the way that people use a piece of land.  Examples of land use include commercial uses such as shopping malls, residential uses such neighborhoods, and agricultural uses such as growing crops or raising animals.

Load (also; loadings) - the amount of pollutants being discharged or deposited into the lake.

Low Flow - minimum flow through a watercourse which will recur with a stated frequency.

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Main stem - the principal river within a given drainage basin, in the case where a number of tributaries discharge into a larger watercourse.

Marsh - a community of water-tolerant, soft-bodied emergent plants and associated animals usually found in a basin of shallow water or on saturated soils fed primarily by underground water sources.

Meander - is a bend in a river. Meanders normally occur in the middle and lower courses where the water is moving more slowly. The river carves out S-shaped bends.

Mega Model - also known as the Muskegon River Ecological Modeling System (MREMS), the Mega Model is a large set of independent models that treat various aspects of the Muskegon River ecosystem, but which are synchronized by shared inputs from climate, land cover, and river network models.

The Michigan Great Lakes Protection Fund - a fund managed by the MDEQ that is a source of reliable funding for new research and demonstration projects to preserve, enhance, and restore the Great Lakes and its component ecosystems.

Minor Civil Divisions (MCDs) - a type of governmental unit that is the primary governmental or administrative division of a county or statistically equivalent entity in many states and statistically equivalent entities. MCDs are identified by a variety of terms, such as township, town, or district.

Model - a representation of a process or system that attempts to relate the most important variables in the system in such a way that analysis of the model leads to insights into the system.

MODFLOW - is a three-dimensional finite-difference groundwater model that simulates steady and non-steady flow in an irregularly shaped flow system in which aquifer layers can be confined, unconfined, or a combination of confined and unconfined.

Muskegon Lake - is a 4,150 acre "drowned river mouth" lake directly connected to Lake Michigan via a channel.

Muskegon River - is a river located in north-central Michigan and is approximately 219 miles long from its start at Houghton and Higgins Lake down to its mouth at Muskegon Lake and, eventually, Lake Michigan. An estimated ninety-four tributaries flow into the main trunk of the Muskegon River.

Muskegon River Watershed (MRW) - is located in north-central Michigan and is one of the largest watersheds in Michigan, second only to the Grand River Watershed. 

Muskegon River Ecological Modeling System (MREMS) - the official name for Mega Model.

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Nitrogen (N) - a chemical element essential for the growth of plants and animals. Our atmosphere is comprised of 79% of nitrogen.

Natural Resources - land, fish, wildlife, biota, air, water, groundwater, drinking water supplies, and other such resources (including the resources of the exclusive economic zone) belonging to, managed by, held in trust by, appertaining to, or otherwise controlled by, the United States, any state or local government or Indian tribe, or any foreign government.

Nutrient - elements or compounds essential as raw materials for organism growth and development, such as carbon, nitrogen and phosphorus. If out of balance can cause impairment of waterways.

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Orchard - an intentional planting of trees or shrubs maintained for food production. Orchards comprise fruit or nut-producing trees grown for commercial production.

Organic Matter - carbonaceous waste contained in plant or animal matter and originating from domestic or industrial sources.

Organism - any form of animal or plant life.

Overland Flow - occurs when the precipitation rate exceeds the infiltration rate of the ground's surface.

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Parts per Million (ppm) - Denotes one part per 1,000,000 parts. This is equivalent to one drop of water diluted into 50 liters (roughly the fuel tank capacity of a compact car), or one second of time in approximately 11½ days.

Peak Flow - the maximum instantaneous discharge of a stream or river at a given location. It usually occurs at or near the time of maximum stage.

Percolation - the movement of water through the openings in rock or soil.

Permanent Pasture - farmland that produces grasses and certain types of legumes which are grazed by animals. The land is continuously used for pasture with tillage only to reestablish the grasses and legumes.

Permeability - the ability of a material to allow the passage of a liquid, such as water through rocks. Permeable materials, such as gravel and sand, allow water to move quickly through them, whereas unpermeable materials, such as clay, do not allow water to flow freely.

Phosphorous (P) - a chemical element essential for growth. It is present in many fertilizers and its overuse may contribute to the formation of algal blooms in waterways.

Pollution - generally, the presence of a substance in the environment that because of its chemical composition or quantity prevents the functioning of natural processes and produces undesirable environmental and health effects. Under the Clean Water Act, for example, the term has been defined as the man-made or man-induced alteration of the physical, biological, chemical, and radiological integrity of water and other media.

Population Growth - is the change in population over time, and can be quantified as the change in the number of individuals in a population using "per unit time" for measurement.

Precipitation - rain, snow, hail, sleet, dew, and frost.

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Rain Fall - the quantity of water that falls as rain only.

Recharge - water added to an aquifer of the groundwater. For instance, rainfall that seeps into the ground.

Reduced Urban Sprawl (RUS) - a future landscapes scenario with a constraint that urban land use in the watershed grows at half the average 1978-1998 rate.

Reforestation - the reestablishment of a forest, either by natural regeneration or by planting in an area where forest was removed.

Reservoir - a pond, lake, or basin, either natural or artificial, for the storage, regulation, and control of water.

Risk Assessment - is a process used to characterize the nature and magnitude of health risks to humans (e.g., residents, workers, recreational visitors) and ecological receptors (e.g., birds, fish, wildlife) from chemical contaminants and other stressors, that may be present in the environment.

River - is a natural stream of water which flows in a channel towards a mouth or lake or another river.

River Bed - part of the stream over which water moves; substrate.

River Channel - also known as a channel.

River Delta (Delta) - a body of sediment deposited at the mouth of a river. Many are roughly triangular in shape.

River Fragmentation - the interruption of a river's natural flow by dams, inter-basin transfers or water withdrawal, and is an indicator of the degree to which rivers have been modified by human activity.

River Mouth - another term meaning “river delta” of “delta”.

River System - a river with all of its tributaries.

Riparian - a type of habitat occurring along the bank of a water course or other water body.

Riparian Buffer - lands adjacent to streams where vegetation is strongly influenced by the presence of water.

Root Zone - the depth or volume of soil from which plants effectively extract water from.

Row Crops - land which is or will be planted with row crops (crops planted in rows a distinguishable distance apart). This land is tilled annually.

Runoff - the part of the precipitation, snow melt, or irrigation water that appears in uncontrolled surface streams, rivers, drains or sewers. Runoff may be classified according to speed of appearance after rainfall or melting snow as direct runoff or base runoff, and according to source as surface runoff, storm interflow, or groundwater runoff.

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Salmonid - refers to any species of fish with an adipose fin, including trout, salmon, whitefish, grayling, and cisco.

Salmonines - refers to true salmon and trout species.

Sand - sedimentary material composed of fragments ranging in diameter from 0.0625 to 2 mm. Sand particles are larger than silt particles but smaller than pebbles.

Saturated - a condition in which all easily drained voids (pores) between soil particles are temporarily or permanently filled with water.

Saturated Zone - underground region within which all openings are filled with water. The top of the zone of saturation is called the Water Table. The water that is contained within the zone of saturation is called groundwater.

Scenario - alternative descriptions or stories of how the future might unfold. They compile information about divergent trends and possibilities into internally consistent images of plausible alternative futures. They are designed to systematically explore future challenges and opportunities and to aid in strategy development.

Sea Level - the height of the surface of the sea midway between the average high and low tides.

Sediment - soil that is in suspension in water or recently deposited from suspension. In the plural the word is applied to all kinds of deposits from the waters of streams, lakes, or seas.

Sediment Load - the soil particles transported through a channel by stream flow. The total sediment, including bedload plus suspended sediment load, is the sediment being moved by flowing water in a stream at a specified cross section.

Sediment Transport - is the movement of solid particles (sediment) due to the movement of the fluid in which they are entrained.

Setback Regulation - a regulation of a certain number of feet can be a requirement for the placement of urban buildings away from a stream-channel bank.

SHMKG (Steelhead Muskegon River) - is a model that integrates output from HEC-RAS modeling of the Muskegon River hydraulics with GIS information of the river substrate and invertebrate population; the output of the model is to project steelhead populations.

Shrub - is a perennial woody plant that branches at ground level to form several stems.

Shrubland - a habitat type dominated by woody shrubs. Shrublands may be either a permanent habitat type or a transitional one, caused when another habitat type is transformed by natural or human disturbances, like fire or logging.

Silt - sedimentary material composed of fragments ranging in diameter from 1/265 to 1/16 mm. Silt particles are larger than clay particles but smaller than sand particles.

Sinuosity (also; sinuosity ratio) - is the distance between two points on the stream measured along the channel divided by the straight line distance between the two points. If the sinuosity ratio is 1.5 or greater the channel is considered to be a meandering one.

Slope - percentage or degree change in elevation over a defined distance.

Snowmelt - in hydrology, snowmelt is surface runoff produced from melting snow.

Spatial - a characteristic that refers to a location (which may be a specific location on the Earth's surface, or relative to an arbitrary point).

Spawn (spawning) - to deposit sperm or eggs into the water.

Spawning grounds (also; spawning areas) - part of a stream or lake that provide suitable area for fish to spawn; usually gravel beds.

Species Composition - the species found in a particular area.

Spillway - the channel or passageway around or over a dam through which excess water is diverted. If the flow is controlled by gates, it is a controlled spillway; if the elevation of the spillway crest is the only control, it is an uncontrolled spillway.

Sprawl Rate - is the ratio of increase in developed land surface to increase in human population size.

Square Mile (sq. mi.) - is an imperial and U.S. unit of measure for an area equal to the area of a square of one statute mile. It is equal to 640 acres or 27,878,400 square feet.

Stakeholder - individuals and organizations with an interest in a particular area, issue or project. Stakeholders may include public agencies at all levels (i.e., federal, state and local), non-profit organizations, private landowners, industry, and others.

Stormflow - surface flow originating from precipitation and run-off which has not percolated to an underground basin.

Streambank Stabilization- natural geological tendency for a stream to mold its banks to conform with the channel of least resistance to flow. Also the lining of streambanks with riprap, matting, etc., to control erosion.

Stream Bed - the channel through which a natural stream of water runs or used to run, as a dry streambed.

Stream Flow - the water discharge that occurs in a natural channel. A more general term than runoff, stream flow may be applied to discharge whether or not it is affected by diversion or regulation.

Sub-basin - a portion of a subregion or basin drained by a single stream or group of minor streams; or the smallest unit into which the land surface is subdivided for hydrologic study purposes.

Sublimation - the change of a solid to a vapor without the appearance of a liquid state, as in the changing of snow directly into water vapor without melting.

Subsoil - soil material underlying the surface soil.

Substrate - any naturally occurring immersed or submersed solid surface, such as a rock or tree, upon which an organism lives.

Succession - the species structure of an ecological community over time.

Surface Area - the wetted area of the lake, excluding islands, in hectares at the time of the survey as calculated from a bathymetric map. Most surveys include wetlands surrounding the lake, but some may not.

Surface Water- water that is on the Earth's surface, such as in a stream, river, lake, or reservoir.

Suspended Load - very fine soil particles that remain in suspension in water for a considerable period of time without contact with the bottom. Such material remains in suspension due to the upward components of turbulence and currents and/or by suspension.

Sustainability - is to deliver environmental, social, and economic services to all residents of a community without threatening the viability of natural, built, and social systems.

Swamp - area of mineral soil normally flooded in the growing season and dominated in most cases by emergent macrophytes (broad-leaved plants), shrubs, and/or trees.

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Temperature - a measure of the energy in a substance. The more heat energy in the substance, the higher the temperature and vice versa.

Temporal - a characteristic that refers to the time at which a given data set was acquired.

Terrestrial - on land; not aquatic.

Throughflow - water moving through the soil.

Total Phosphorus (TP) - the total concentration of phosphorus found in the water. Phosphorus is a nutrient and acts as a fertilizer, increasing the growth of plant life such as algae.

Transpiration - process by which water that is absorbed by plants, usually through the roots, is evaporated into the atmosphere from the plant surface, such as leaf pores.

Tributary (also; tributaries) - a stream or river flowing into a larger river. The water being drained from two areas now flows in one main channel. A river grows as more tributaries flow into it.

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Unsaturated Zone - the subsurface zone between the water table (Zone of Saturation) and the land surface where some of the spaces between the soil particles are filled with air.

Urbanization - the concentration of population around towns and cities. Associated with this process is the replacement of pervious surfaces with impervious materials such as asphalt and concrete.

Urban Expansion - another term meaning “urban sprawl”.

Urban Land Use - is a classification that encompasses all types of land that has been developed for human uses, including residential, industrial, commercial, and transportation. Most of the time these areas are covered by structures, but urban land can also be areas that are used for mining or recreation.

Urban Sprawl - the decentralization of the urban core through the unlimited outward extension of dispersed development beyond the urban fringe where low density residential and commercial development exacerbates fragmentation of powers over land use; also, the consumption of resources and land in excess of what is necessary where development is costly and underutilizes existing infrastructure.

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Velocity - rate of motion of a stream measured in terms of the distance its water travels in a unit of time, usually expressed in feet per second.

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Water Quality - Most generally described as the physical, chemical and biological integrity of the water.

Watershed - is an extent of land where water from rain or snow melt drains downhill into a body of water, such as a river, lake, reservoir, estuary, wetland, or ocean. The drainage basin includes both the streams and rivers that convey the water as well as the land surfaces from which water drains into those channels, and is separated from adjacent basins by a drainage divide.

Watershed Management - is the process of creating and implementing plans, programs, and projects to sustain and enhance watershed functions that affect the plant, animal, and human communities within a watershed boundary.

Water Balance - a measure of the amount of water entering and the amount of water leaving a system; also referred to as Water Budget.

Water Budget - another term meaning “water balance”.

Water Table- the top of the water surface in the saturated part of an aquifer.

Wetland - an area that is saturated by surface or ground water with vegetation adapted for life under those soil conditions, as swamps, bogs, fens, marshes, and estuaries.

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This project is funded by the Great Lakes Fishery Trust as part of the Muskegon River Watershed Initiative.
Contact John Koches at for website information.



Page last modified December 5, 2011