Mariner's Dictionary

°C - Degrees Celsius

°F - Degrees Fahrenheit

Acre - A measure of land area measuring 43,560 square ft

Acre-feet - The amount of water it takes to cover one acre to a depth of one foot, 43,560 cubic ft or 1,233.5 cubic meters

Active Storage - The volume of water in a reservoir between its minimum operating elevation and its maximum normal operating elevation

Adit - An almost vertical pipe or short horizontal passage entering a tunnel, either to add water from a conduit, sluice or other water source or as a maintenance access tunnel (also referred to as a portal if located at the beginning or end of the tunnel)

Afterbay - A reservoir located immediately downstream from a powerhouse, sometimes used to re-regulate flows to the river or stream

Alluvium - Material such as sand, silt or clay, deposited on land by water such as on floodplains

Anadromous fish - Fish that live in saltwater habitats most of their lives, but periodically migrate into freshwater to spawn and develop to the juvenile stage (e.g., striped bass)

APE - Area of Potential Effect as pertaining to Section 106 of the National Historic Preservation Act

Aquatic Life - Any plants or animals which live at least part of their life cycle in water

Automatic Powerhouses - An automatic powerhouse can be started, stopped, and have its load and voltage changed from a remote or master station, via supervisory control.

Base Load - A power plant that is planned to run continually except for maintenance and scheduled or unscheduled outages. Also refers to the nearly steady level of demand on a utility system.

Baseline - A set of existing environmental conditions upon which comparisons are made during the NEPA process

Benthic - Associated with lake or river bottom or substrate

Benthic Macroinvertebrates - Animals without backbones, which are visible to the eye and which live on, under, and around rocks and sediment on the bottoms of lakes, rivers, and streams

Billions of Cubic Meters - A water consumption measurement unit for large cities.

Black Start Capability - The ability of a unit to start up without the use of an external transmission or distribution voltage power source

Brig - A two-masted, square rigged vessel

Capacity - The load for which an electric generating unit, or other electrical equipment or power line is rated

Catadromous fish - Fish that live in freshwater most of their lives and when mature migrate to the sea to spawn (e.g., American eel)

Clean Water Act - The Federal Water Pollution Control Act of 1972 and subsequent amendments in 1977, 1981, and 1987 (commonly referred to as the Clean Water Act). The Act established a regulatory system for navigable waters in the United States, whether on public or private land. The Act set national policy to eliminate discharge of water pollutants into navigable waters, to regulate discharge of toxic pollutants, and to prohibit discharge of pollutants from point source without permits. Most importantly it authorized EPA to set water quality criteria for states to use to establish water quality standards.

Colluvium - Soil material and/or rock fragments moved by gravity such as during creep, slide, or localized wash-outs, which is deposited at the base of steep slopes

Combustion turbine - A fuel-fired turbine engine used to drive an electric generator

Commission - Federal Energy Regulatory Commission also referenced as FERC

Conduit - A tunnel or pipe, used for diverting or moving water from one point to another, usually used when there is no existing streambed or waterway

Conservation - A process or program designed to increase the efficiency of energy and water use, production, or distribution

Creel Census - Counting and interviewing anglers to determine fishing effort and catch. Usually conducted by a census clerk on systematic regularly scheduled visits to significant fishing areas.

Critical Energy Infrastructure Information - Project-related documents that are restricted from public viewing in accordance with FERC regulations (18 CFR 388.113) related to the design and safety of dams and appurtenant facilities, and that is necessary to protect national security and public safety

Cubic Feet - The volume of a cube with edges one foot in length

Cubic feet per Second - A measurement of water flow representing one cubic foot of water moving past a given point in one second. One cfs is equal to 0.0283 cubic meters per second and 0.646 mgd.

Cultural Resources - Includes items, structures, etc. of historical, archaeological, or architectural significance

Cumulative Impact - The effect on the environment that results from the incremental impact of the action when added to other past, present, and reasonably foreseen future actions. Can result from individually minor but collectively significant actions taking place over a period of time.

Dam - A structure constructed across a water body typically used to increase the hydraulic head at hydroelectric generating units. A dam typically reduces the velocity of water in a particular river segment and increases the depth of water by forming an impoundment behind the dam. It also generally serves as a water control structure.

Demand - The rate at which electric energy is delivered to or by a system at a given instant or averaged over a designated period, usually expressed in kilowatts or megawatts

Dependable Capacity - The maximum dependable MW output of a generator or group of generators during the critical hydrologic period coincident with peak electrical system load

Development - One of several hydroelectric plants collectively licensed by the Federal Energy Regulatory Commission as a Project (e.g., The Coosa River Project consists of five developments: Weiss, Henry, Logan Martin, Lay, and Bouldin)

Dike - A raised bank, typically earthen, constructed along a waterway to impound the water and to prevent flooding

Dissolved Oxygen - A commonly employed measure of water quality that describes the amount of oxygen dissolved in water. Low DO levels adversely affect aquatic life.

Distribution Lines - Power lines, like those in neighborhoods, used to carry moderate voltage electricity which is "stepped down" to household levels by transformers on power poles

Distribution System - The substations, transformers and lines that convey electricity from high-voltage transmission lines to the consumer

Drawdown - The distance the water surface of a reservoir is lowered from a given elevation as the result of releasing water

Emergent aquatic vegetation - Plants rooted in substrate covered by shallow water (of up to 6.6 ft depth), with most of the parts out of the water

Energy - Average power production over a stated interval of time, expressed in kilowatt-hours, megawatt-hours, average kilowatts and average megawatts

Environmental Impact Statement - An environmental review document prepared under NEPA to determine the environmental impact of a specific action. A Draft Environmental Impact Statement (DEIS) is prepared and circulated for public comment. After incorporation of public comments, a Final Environmental Impact Statement (FEIS) is published.

Eutrophic - Waters with a high concentration of nutrients and a high level of primary production

Evapotranspiration - The evaporation from all water, soil, snow, ice, vegetation, and other surfaces, plus transpiration

Federal Energy Regulatory Commission - The governing federal agency responsible for overseeing the licensing/relicensing and operation of hydroelectric projects in the United States

Federal Power Act - Federal statute enacted in 1920 that established the Federal Power Commission (now FERC) and the statutes for licensing hydroelectric projects

Federal Power Commission - Predecessor of FERC

Federal Register - A publication of the Federal Government that includes official transactions of the U.S. Congress, as well as all federal agencies such as FERC. Copies of the Federal Register are usually available at large public and university libraries.

Flow - The volume of water passing a given point per unit time

Flow Duration Curve - A graphical representation of the percentage of time in the historical record that a flow of any given magnitude has been equaled or exceeded

Forebay - A reservoir upstream from a powerhouse, from which water is drawn into a tunnel or penstock for delivery to the powerhouse (The Lake)

Francis turbine - A radial-inflow reaction turbine, where flow through the runner is perpendicular to the turbine shaft

Generation - The process of producing electricity from other forms of energy, such as steam, heat, or water. Refers to the amount of electric energy produced, expressed in kilowatt hours

Generator - A machine that converts mechanical energy into electricity often powered by a turbine

Grizzly trash rack - A metal grating across the entry to a water conduit

Gross Storage - The sum of the dead storage and the live storage volumes of a reservoir, the total amount of water contained in a reservoir at its maximum normal operating elevation

H-Frame Structure - A wood pole transmission structure that consists of two wood poles with a horizontal cross arm above the conductor

Habitat - The locality or external environment in which a plant or animal normally lives and grows

Head - The distance that water falls in passing through a hydraulic structure or device such as a hydroelectric plant. Gross head is the difference between the headwater and tailwater levels; net head is the gross head minus hydraulic losses such as friction incurred as water passes through the structure; and rated head is the head at which the full-gate discharge of a turbine will produce the rated capacity of the connected generator.

Headwater - The waters immediately upstream of a dam. For power dams, also referred to as the water in the impoundment which supplies the turbines (see also forebay).

Headworks - In relation to a dam, the top of the dam with gates where water flows

Horsepower - A measure of power equal to about 746 watts

Hydraulic - Relating to water in motion

Hydroelectric Plant - A facility at which the turbine generators are driven by falling water

Hydroelectric Power - Capturing flowing water to produce electrical energy

Hydrologic Unit Code - Developed by the Water Resources Council corresponding to hierarchal classification of hydrologic drainage basins in the United States. Each hydrologic unit is identified by a unique hydrologic unit code (HUC).

Hypolimnetic - The deeper cooler portions of a reservoir or lake that result from stratification

Hz - hertz (cycles per second)

Impoundment - The body of water created by a dam

Induced Surcharge Curve - A set of lake level elevations used to manage flows during periods of high inflow to ensure protection of downstream lands from flooding

Installed Capacity - The nameplate MW rating of a generator or group of generators

Integrated Licensing Process - The ILP is the default process by which a hydropower project obtains a new license to operate

Interested parties - Individuals who have expressed and interest in the relicensing proceeding

Kilovolts - A unit of pressure, or push, of an electric current equal to 1,000 volts

Kilowatt - A unit of electrical power equal to 1,000 watts or 1.341 horsepower

Kilowatt-hour - Basic unit of electric energy equal to an average of one kilowatt of power applied over one hour

Lacustrine - Pertaining to or living in lakes or ponds

Lake Rule Curve - A set of target lake level elevations that vary seasonally. The lake level is normally maintained at or below the elevations specified by the rule curve, except when storing floodwater. Rule curves are often set by federal agencies responsible for operating storage reservoirs, such as the Army Corp of Engineers.

Latitude - North / South Measurement: Angular distance north or south of the earth's equator, measured in degrees along a meridian, as on a map or globe. The equator is at 0 degrees. The North Pole is at +90 degrees or 90 degrees north. The South Pole is at –90 degrees or 90 degrees south.

Lentic - Standing or still water including lakes, ponds and swamps

License - FERC authorization to construct a new project or continue operating and existing project. The license contains the operating conditions for a term of 30 to 50 years.

License Application - Application for a new license; submitted to FERC no less than two years in advance of expiration of an existing license

Licensee - This is another term that refers to the Alabama Power Company (APC)

Littoral - Associated with shallow (shoreline area) water (e.g., the littoral zone of an impoundment)

Load - The total consumer demand of electric service at any given time

Longitude - East / West Measurement: Angular distance on the earth's surface, measured east or west from the prime meridian at Greenwich, England, to the meridian passing through a position, expressed in degrees (or hours), minutes, and seconds. Longitudes are measured from zero to 180° east and 180° west (or -180°), and both 180-degree longitudes share the same line, in the middle of the Pacific Ocean.

Lotic - Flowing or actively moving water including rivers and streams

Mainstream - The main channel of a river a opposed to the streams and smaller rivers that feed into it

Manual Powerhouses - A semi-automatic powerhouse without SCADA will send alarms to a remote or master station. A manual powerhouse must have all its functions performed at the powerhouse.

Martin Datum - Local datum of the Lake Martin project; equivalent to 491 ft mean sea level

Maximum drawdown elevation - The lowest surface elevation to which a reservoir can be lowered and still maintain generation capability. This is usually somewhat lower than the minimum operating elevation.

Maximum normal operating elevation - The maximum surface elevation to which the reservoir can be raised without surcharging or exceeding the license provisions

Megawatt - A unit of electrical power equal to one million watts or 1,000 kW

Megawatt-hour - A unit of electrical energy equal to 1 MW of power used for one hour

Minimum normal operating elevation - The lowest elevation to which a reservoir is normally lowered during power generation operations. Below this point power output and generation efficiency is significantly impacted.

Nameplate Capacity - A measurement indicating the approximate generating capability of a project or unit, as designated by the manufacturer. In many cases, the unit is capable of generating substantially more than the nameplate capacity since most generators installed in newer hydroelectric plants have a continuous overload capacity of 115 percent of the nameplate capacity. Also called Installed Capacity.

National Environmental Policy Act - A law passed by the U.S. Congress in 1969 to establish methods and standards for review of development projects requiring Federal action such as permitting or licensing

Non-Governmental Organization - Local, regional and national organizations such as conservation, sportsman’s or commerce groups

Normal Operating Capacity - The maximum MW output or a generator or group of generators under normal maximum head and flow conditions

Normal Operating Elevation - The reservoir elevation approximating an average surface elevation at which a reservoir is kept

Normal Operating Elevation Range - The elevation difference between the normal maximum and normal minimum operating elevations

Off Peak - A period of relatively low demand for electrical energy, such as the middle of the night

On Peak - A period of relatively high demand for electrical energy

Outage - The period during which a generating unit, transmission line, or other facility is out of service

Palustrine Emergent Wetland - Contains rooted herbaceous vegetation that extend above the water surface (i.e., cattails, sedges)

Palustrine Forested Wetland - Dominated by woody vegetation less than 20 ft tall (i.e., willows, dogwood)

Palustrine Scrub/Shrub Wetland - Comprised of woody vegetation that is 20 ft tall or greater (i.e., American elm, swamp white oak)

Peak Demand - A one hour period in a year representing the highest point of customer consumption of electricity

Peaking Operations - A powerplant that is scheduled to operate during peak energy demand. Operation of generating facilities to meet maximum instantaneous electrical demands

Periphyton - Macroscopic (visible without a microscope) and microscopic (visible only with a microscope) algae (single- and multi-celled plants) that grow on or attach to rocks, logs, and aquatic plants. Periphyton, phytoplankton, and aquatic plants are the primary producers that convert nutrients into plant material by the process of photosynthesis.

Phytoplankton - Microscopic single-celled and colonial forms of algae floating in the water column

Piezometer - A device that measures water pressure

Ponding Operations - The process of storing and releasing water based on electric demand or flood control

Pool - Refers to the reservoir or an impounded body of water

Power Factor - The ratio of actual power to apparent power. Power factor is the cosine of the phase angle difference between the current and voltage of a given phase. Unity power factor exists when the voltage and current are in phase.

Power Pool - A regional organization of electric companies interconnected for the sharing of reserve generating capacity.

Powerhouse - The building that typically houses electric generating equipment

Pre-Application Document - A document, required by FERC when relicensing a project, that brings together all existing, relevant, and reasonably available information about the project and its effects on resources; and includes a well-defined process plan that sets the schedule for developing the license application and a list of preliminary studies and issues.

Probable Maximum Flood - A statistical formula used to calculate a hypothetical flood event that could occur on a particular river basin over a particular duration. This is derived from the probable maximum precipitation over time.

Project - This refers to Alabama Power Company’s Martin Hydroelectric Project, FERC Project No. 349

Project Area - The geographic area defined in the license issued by FERC for the Project as needed for Project operations and maintenance

Project Boundary - The boundary defined in the license issued by FERC for the Project outlining the geographic area needed for Project operations and maintenance

Project Drainage Basins - The area of land that contributes surface water to the Tallapoosa River system

Project Region - The area around the Project on the order of a County or National Forest in size

Project Roads - Roads within Project Boundary and constructed for Project purposes and necessary for Project operation and maintenance

Project Vicinity - The area extending to about five miles from the Project Boundary

Project Viewshed - The area from which Project features are visible. The land base from which the Project may be seen.

Project Works - All of the infrastructure associated with the operations of the Project

Protection - All of the relays and other equipment which are used to open the necessary circuit breakers to separate pieces of equipment from each other when trouble develops

Protective Relay - A device whose function is to detect defective lines or apparatus, or other power system conditions of an abnormal or dangerous nature, and to initiate appropriate control circuit action

Public Reference File - A listing of important materials pertaining to the relicensing

Public Utility - A business enterprise rendering a service considered essential to the public and, as such, subject to regulation

Ramp Rate - The rate of change in output from a power plant. A maximum ramp rate is sometimes established to prevent undesirable effects due to rapid changes in loading or, in the case of hydroelectric plants, discharge.

Ramping - The act of increasing or decreasing stream flows from a powerhouse, dam or division structure

Regulated Hydrology - The hydrology of Project-affected streams subsequent to construction of the Project

Relicensing - The administrative proceeding in which FERC, in consultation with other federal and state agencies, decide whether and on what terms to issue a new license for an existing hydroelectric project at the expiration of the original license

Relicensing Participants - Individuals who actively participate in the relicensing proceedings

Reserve Capacity - Extra generating capacity available to meet unanticipated demand for power or to generate power in the event of loss of generation

Reservoir - An artificial lake into which water flows and is stored for future use

Reservoir Useable Capacity - A volume measurement of the amount of water that can be stored for generation, down to a minimum level

Resident Fish - Fish that spend their entire life cycle in freshwater, such as sunfish and bass

Resource Agency - A federal, state, or interstate agency with responsibilities in the areas of flood control, navigation, irrigation, recreation, fish or wildlife, water resource management, or cultural or other relevant resources of the state in which a project is or will be located.

Rhizome - Underground stem

Riparian Area - A specialized form of wetland with characteristic vegetation restricted to areas along, adjacent to or contiguous with rivers and streams. Also, periodically flooded lake and reservoir shore areas, as well as lakes with stable water.

River Miles - Miles from the mouth of a river; for upstream tributaries, from the confluence with the main river

Run-of-River - A term used to describe the operation of a hydroelectric project in which the quantity of water discharged from the project essentially equals the flow in the river

Runner - The rotating part of a turbine

Scoping Document 1 - A document prepared by FERC as part of NEPA environmental review that initially identifies issues pertinent to FERC's review of a project. FERC circulates the SD1 and holds a public meeting to obtain the public's comment.

Scoping Document 2 - A revision to SD1 which takes into account public comment on that document

Scoping process - The process of identifying issues, potential impacts, and reasonable alternatives associated with the operation of a hydroelectric project. "Scoping" is a process required by any federal agency taking an action that might affect the quality of the human environment, pursuant to the National Environmental Policy Act (NEPA) of 1969. In the case of hydro projects, FERC's issuance of an operating license qualifies as a federal action.

Secchi depth - Average depth at which a standard size black and white disk disappears and reappears when viewed from the lake surface as it is lowered. An indicator of water clarity.

Seepage - The amount of water that leaks through a structure, such as a dam

Semi-automatic Powerhouses - A semiautomatic powerhouse with SCADA may allow a remote station to change load and/or voltage, and may allow a remote shutdown, but must be started manually.

Spawn - The act of fish releasing and fertilizing eggs

Spawning Run - A general term referring to migration of anadromous or catadromous fish over a particular time and area

Spillway - A passage for releasing surplus water from a reservoir or canal

Stakeholder - Any individual or organization (government or non-governmental) with an interest in a hydroelectric project

State - State of Alabama

Stock - The introduction of a particular species of fish into an aquatic system as part of a resource management plan or goal.

STORET - The USEPA’s computerized water quality data storage system

Stratification - A physical and chemical process that results in the formation of distinct layers of water within a lake or reservoir (i.e., epilimnion, metalimnion, and hypolimnion)

Streamflow - The rate at which water passes a given point in a stream, usually expressed in cubic ft per second (cfs)

Study Description - A detailed description of an individual study

Study Plan - The aggregate of all study descriptions

Submerged Aquatic Vegetation - Plants with rigid stems and/or leaves rooted in substrate and generally covered by deep water (greater than 6.6 ft depth), with all of the plant parts covered by water

Tailrace - The channel located between a hydroelectric powerhouse and the river into which the water is discharged after passing through the turbines

Tailwater - The waters immediately downstream of a dam. For power dams, also referred to as the water discharged from the draft tubes.

Tainter Gate - A gate with a curved skin or face plate connected with steel arms to an axle. It is usually lifted or lowered by a cable connected to a hook at the top of the gate rotating on the axle as it is moved.

Taxon - A means of referring to a set of animals or plants of related classification, such as all of the species (i.e., brook trout, lake trout) in a genus (trout); or all of the genera (all trout and salmon) in a family of fishes (salmonidae). Plural form of taxon is taxa.

Transformer - Equipment vital to the transmission and distribution of electricity designed to increase or decrease voltage

Transmission - The act or process of transporting electric energy in bulk from one point to another in the power system, rather than to individual customers

Transmission Lines - Power lines normally used to carry high voltage electricity to substations which then is "stepped down" for distribution to individual customers

Transpiration - The process by which water absorbed by plants is converted to vapor and discharged to the atmosphere

Trash Rack - A series of vertical steel bars found on a dam or intake structure, which clears the water of debris before the water passes through the structure

Turbidity - A measure of the extent to which light passing through water is reduced due to suspended materials

Turbine - A machine for generating rotary mechanical power from the energy in a stream of fluid (such as water, steam, or hot gas). Turbines covert the energy of fluids to mechanical energy through the principles of impulse and reaction, or a mixture of the two.

Vantage Point - The location from which a viewer sees the landscape

Volt - The unit of electromotive force or electric pressure, akin to water pressure in pounds per square inch

Warmwater Fish - Fish species typical of southeastern warm water environments (e.g., bass, sunfish, pickerel, sucker)

Watershed - An entire drainage basin including all living and nonliving components of the system

Wetlands - Lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallow water. Wetlands must have the following three attributes: 1) at least periodically, the land supports predominantly hydrophytes; 2) the substrate is predominantly undrained hydric soil; 3) the substrate is on soil and is saturated with water or covered by shallow water at some time during the growing season of each year.

Zooplankton - Microscopic and macroscopic animals that swim in the water column. These invertebrates include chiefly three groups: rotifers, cladocerans, and copepods.

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