CESSWI Definitions Exam With Complete
Solutions A+ Graded
Plant Transpiration - ANSWER The loss of water from parts of plants especially leaves
but also stems, flowers, and roots.
Plunge - ANSWER Flow with a strong downward component, as in outfall drops,
overbank falls, and surf attack on a beach.
Point of Concentration - ANSWER That point at which the water flowing from a given
drainage area concentrates.
Point Sources - ANSWER A source of pollutants from a single point of conveyance such
as a pipe. For example, the discharge pipe from a sewage treatment plant or factory is a
point source.
Steady Stream - ANSWER A term used by river engineers applying to a stream that over
a period of time is neither degrading nor aggrading its channel, and is nearly in
equilibrium as to sediment transport and supply.
PAHs Polycyclic Aromatic Hydrocarbons Chemical compounds that contain fused
aromatic rings and do not contain heteroatoms or carry substituents. These occur in oil,
coal and tar deposits and are produced as by products of fuel burning whether in the
form of fossil fuel or biomass. Of concern, as a pollutant, since some compounds have
been identified to be carcinogenic, mutagenic and teratogenic.
Positive Projecting Conduit - ANSWER A structure placed in shallow trench with the top
of the conduit projecting above the top of the trench and then covered with
embankment. (See Negative Projecting Conduit.)
,Potamology - ANSWER The hydrology of streams.
Practicable - ANSWER Capable of being done within reasonable natural, social, and
economic constraints.
Rainfall - ANSWER Discharge of atmospheric moisture as rain, snow or hail, measured
in depth of fall or in terms of intensity of fall in unit time.
Prescriptive Rights - ANSWER The operation of the law whereby rights may be
established by long exercise of their corresponding powers or extinguished by
prolonged failure to exercise such powers.
Preserve - ANSWER To prevent alteration to the functions of the natural floodplain
environment or to keep it, as closely as practicable, in its natural state.
Probability - ANSWER The likelihood of occurrence or recurrence of a specified event
within a unit of time, commonly expressed in 3 ways. Thus a 10-year flood has a
likelihood of 0.1 per year and is also termed a 10%-chance flood.
Publicly Owned Treatment Works (POTW) - ANSWER A waste-treatment works owned
by a state, unit of local government, or Indian tribe, usually designed to treat domestic
wastewaters.
Quality Assurance Project Plan QAPP ANSWER The QAPP has been created by the EPA
as a tool for project managers and planners to document the type and quality of data
required for environmental decisions, and to describe the methods for collecting and
assessing those data. The development, review, approval and implementation of the
QAPP are all components of EPA's required Quality System.
Rainfall - ANSWER Point Precipitation: That which registers at a single gauge. Area
Precipitation: Adjusted point rainfall for area size.
Rainwash - ANSWER The creep of soil lubricated by rain.
,Range - ANSWER Difference between extremes, as for stream or tide stage.
Rapidly Varied Flow - ANSWER A type of flow in which depth and velocity vary over short
distances, the acceleration forces predominate, and friction losses are small.
Rapids - ANSWER A steep, rough reach of river with swift, turbulent flow.
Ravine - ANSWER Larger than gulch, smaller than canyon and less bold in relief than
gulch or arroyo.
Reach - ANSWER The length of a channel uniform with respect to discharge, depth,
area, and slope. More generally, any length of a river or drainage course.
Recession - ANSWER Retreat of shore or bank by progressive erosion.
Reduction - ANSWER Part of a reduction-oxidation (redox) reaction in which atoms have
their oxidation number (oxidation state) changed.
Reef - ANSWER Generally, any solid projection from the bed of a stream or other body of
water.
Regime - ANSWER The system or order characteristic of a stream; its behavior with
respect to velocity and volume, form of and changes in channel, capacity to transport
sediment, amount of material supplied for transportation, etc.
Regimen - ANSWER The characteristic behavior of a stream during ordinary cycles of
flow.
Regulatory Floodway The open floodplain area that is confined by Federal, State, or
local requirements, i.e., unconfined or unobstructed either horizontally or vertically, to
, provide for the discharge of the base flood so that the cumulative increase in water
surface elevation is no more than a designated amount (not to exceed 0.3048 m as
established by the Federal Emergency Management Agency (FEMA) for administering
the National Flood Insurance Program (NFIP)).
Regulatory Framework - ANSWER A particular set of laws, rules, procedures, and
agencies designed to control a particular type of activity or to solve a specific program.
Reliction - ANSWER Relating to left behind. Example: that portion of land is left behind
by reliction in case the water surface of a lake is lowered.
Repose - ANSWER Stable slope of a bank or embankment, expressed as an angle or the
ratio of horizontal to vertical projection.
Restore - ANSWER To reestablish a setting or environment inwhich the functions of the
natural and beneficial floodplain values adversely impacted by a development can
continue to operate.
Restriction - ANSWER Artificial or natural control against widening of a channel, with or
without construction.
D retard - ANSWER Bank-protection structure designed to check the riparian velocity
and induce silting or accretion.
Detention basin ANSWER Either natural or man-made basin but with the specific
purpose of delaying the flow of water from one point to another. This tends to increase
the time taken for all the water falling on the extremities of the drainage basin to reach a
common point, resulting in reduced peak flow at that point.
Retention - ANSWER The holding of runoff in a basin without release except by means of
evaporation, infiltration, or emergency bypass.
Retention Storage - ANSWER Water that accumulates and ponds in natural or excavated
Solutions A+ Graded
Plant Transpiration - ANSWER The loss of water from parts of plants especially leaves
but also stems, flowers, and roots.
Plunge - ANSWER Flow with a strong downward component, as in outfall drops,
overbank falls, and surf attack on a beach.
Point of Concentration - ANSWER That point at which the water flowing from a given
drainage area concentrates.
Point Sources - ANSWER A source of pollutants from a single point of conveyance such
as a pipe. For example, the discharge pipe from a sewage treatment plant or factory is a
point source.
Steady Stream - ANSWER A term used by river engineers applying to a stream that over
a period of time is neither degrading nor aggrading its channel, and is nearly in
equilibrium as to sediment transport and supply.
PAHs Polycyclic Aromatic Hydrocarbons Chemical compounds that contain fused
aromatic rings and do not contain heteroatoms or carry substituents. These occur in oil,
coal and tar deposits and are produced as by products of fuel burning whether in the
form of fossil fuel or biomass. Of concern, as a pollutant, since some compounds have
been identified to be carcinogenic, mutagenic and teratogenic.
Positive Projecting Conduit - ANSWER A structure placed in shallow trench with the top
of the conduit projecting above the top of the trench and then covered with
embankment. (See Negative Projecting Conduit.)
,Potamology - ANSWER The hydrology of streams.
Practicable - ANSWER Capable of being done within reasonable natural, social, and
economic constraints.
Rainfall - ANSWER Discharge of atmospheric moisture as rain, snow or hail, measured
in depth of fall or in terms of intensity of fall in unit time.
Prescriptive Rights - ANSWER The operation of the law whereby rights may be
established by long exercise of their corresponding powers or extinguished by
prolonged failure to exercise such powers.
Preserve - ANSWER To prevent alteration to the functions of the natural floodplain
environment or to keep it, as closely as practicable, in its natural state.
Probability - ANSWER The likelihood of occurrence or recurrence of a specified event
within a unit of time, commonly expressed in 3 ways. Thus a 10-year flood has a
likelihood of 0.1 per year and is also termed a 10%-chance flood.
Publicly Owned Treatment Works (POTW) - ANSWER A waste-treatment works owned
by a state, unit of local government, or Indian tribe, usually designed to treat domestic
wastewaters.
Quality Assurance Project Plan QAPP ANSWER The QAPP has been created by the EPA
as a tool for project managers and planners to document the type and quality of data
required for environmental decisions, and to describe the methods for collecting and
assessing those data. The development, review, approval and implementation of the
QAPP are all components of EPA's required Quality System.
Rainfall - ANSWER Point Precipitation: That which registers at a single gauge. Area
Precipitation: Adjusted point rainfall for area size.
Rainwash - ANSWER The creep of soil lubricated by rain.
,Range - ANSWER Difference between extremes, as for stream or tide stage.
Rapidly Varied Flow - ANSWER A type of flow in which depth and velocity vary over short
distances, the acceleration forces predominate, and friction losses are small.
Rapids - ANSWER A steep, rough reach of river with swift, turbulent flow.
Ravine - ANSWER Larger than gulch, smaller than canyon and less bold in relief than
gulch or arroyo.
Reach - ANSWER The length of a channel uniform with respect to discharge, depth,
area, and slope. More generally, any length of a river or drainage course.
Recession - ANSWER Retreat of shore or bank by progressive erosion.
Reduction - ANSWER Part of a reduction-oxidation (redox) reaction in which atoms have
their oxidation number (oxidation state) changed.
Reef - ANSWER Generally, any solid projection from the bed of a stream or other body of
water.
Regime - ANSWER The system or order characteristic of a stream; its behavior with
respect to velocity and volume, form of and changes in channel, capacity to transport
sediment, amount of material supplied for transportation, etc.
Regimen - ANSWER The characteristic behavior of a stream during ordinary cycles of
flow.
Regulatory Floodway The open floodplain area that is confined by Federal, State, or
local requirements, i.e., unconfined or unobstructed either horizontally or vertically, to
, provide for the discharge of the base flood so that the cumulative increase in water
surface elevation is no more than a designated amount (not to exceed 0.3048 m as
established by the Federal Emergency Management Agency (FEMA) for administering
the National Flood Insurance Program (NFIP)).
Regulatory Framework - ANSWER A particular set of laws, rules, procedures, and
agencies designed to control a particular type of activity or to solve a specific program.
Reliction - ANSWER Relating to left behind. Example: that portion of land is left behind
by reliction in case the water surface of a lake is lowered.
Repose - ANSWER Stable slope of a bank or embankment, expressed as an angle or the
ratio of horizontal to vertical projection.
Restore - ANSWER To reestablish a setting or environment inwhich the functions of the
natural and beneficial floodplain values adversely impacted by a development can
continue to operate.
Restriction - ANSWER Artificial or natural control against widening of a channel, with or
without construction.
D retard - ANSWER Bank-protection structure designed to check the riparian velocity
and induce silting or accretion.
Detention basin ANSWER Either natural or man-made basin but with the specific
purpose of delaying the flow of water from one point to another. This tends to increase
the time taken for all the water falling on the extremities of the drainage basin to reach a
common point, resulting in reduced peak flow at that point.
Retention - ANSWER The holding of runoff in a basin without release except by means of
evaporation, infiltration, or emergency bypass.
Retention Storage - ANSWER Water that accumulates and ponds in natural or excavated
