Iowa Administrative Code › Agency 567 - Environmental Protection Commission › Title V - Flood Plain Development › Chapter 70 - Scope of Title-definitions-forms-rules of Practice › Rule 567-70.2 - Definitions

Current through Register Vol. 47, No. 3, July 24, 2024
Definitions used in this title are listed in alphabetical
				  order as follows:
"Agricultural levees or dikes"
means levees
				  or dikes constructed to provide limited flood protection to land used primarily
				  for agricultural purposes.
"Animal feeding operation"
means the same as
				  defined in 567-65.1 (459,459B).
"Animal feeding operation structure"
means
				  the same as defined in
				  567-65.1 (459,459B).
"Backwater"
means the increase in water
				  surface level immediately upstream from any structure, dam, obstruction or
				  deposit, erected, used, or maintained in the floodway or on the floodplains
				  caused by the resulting reduction in conveyance area.
"Building"
means all residential housing
				  including mobile homes as defined herein, cabins, factories, warehouses,
				  storage sheds, and other walled, roofed structures constructed for occupation
				  by people or animals or for storage of materials.
"Channel"
means a natural or artificial flow
				  path of a stream with definite bed and banks to collect and conduct the normal
				  flow of water.
"Channel change"
means either (a) the
				  alteration of the location of a channel of a stream or (b) a substantial
				  modification of the size, slope, or flow characteristics of a channel of a
				  stream for a purpose related to the use of the stream's floodplain surface
				  rather than for the purpose of actually using the water itself, or putting the
				  water to a new use. (Note: Diversions of water subject to the permit
				  requirements of Iowa Code sections
				  455B.268 and
				  455B.269
				  usually are not channel changes.) Increasing the cross-sectional area of a
				  channel by less than 10 percent is not considered a substantial modification of
				  the size, slope, or flow characteristics of a channel of a stream.
"Confinement feeding operation"
means the
				  same as defined in 567-65.1 (459,459B).
"Confinement feeding operation building"
or
"confinement building"
means the same as defined in
				  567-65.1 (459,459B).
"Confinement feeding operation structure"
means the same as defined in
				  567-65.1 (459,459B).
"Dam"
means the same as defined in rule
				  567-73.2 (455B).
"Development"
means a structure, dam,
				  obstruction, deposit, excavation or flood control work in a floodway or
				  floodplain.
"Drainage district ditch"
means a channel
				  located within the boundaries of a drainage district and excavated to establish
				  a design channel-bottom profile for efficient conveyance of water discharged
				  from agricultural tile systems and open drains.
"Elevating"
means raising buildings by fill
				  or other means to or above a minimum level of flood protection.
"Encroachment limits"
means the boundaries
				  of the floodway established in the floodplains and designating the width of the
				  channel and minimum width of the overbank areas needed for the conveyance of
				  Q100.
"Equal and opposite conveyance"
means the
				  location of development offsets from stream banks so that floodplain lands on
				  each side of a stream convey a share of the flood flows proportionate to the
				  total conveyance available on each respective side of the stream.
"Experienced Iowa flood chart"
means a plot
				  on logarithmic graph paper of points representing floods which have been
				  observed and measured in Iowa and subsequently published by the U.S. geological
				  survey or other agency. Each point on the plot is located with the drainage
				  area in square miles as the abscissa and discharge in cubic feet per second as
				  the ordinate.
"Flood control works"
means physical works
				  such as dams, levees, floodwalls, and channel improvements or relocations
				  undertaken to provide moderate to high degree of flood protection to existing
				  or proposed structures or land uses.
"Flood hazard area"
means the area including
				  the floodplains and the river or stream channel.
"Floodplain"
means the land adjacent to a
				  stream which has been or may be inundated by a flood having the magnitude of
				  the regional flood as defined in these rules.
"Flood proofing"
means a combination of
				  structural provisions, changes, or adjustments in construction to buildings,
				  structures, or properties subject to flooding primarily for the reduction or
				  elimination of flood damages.
"Floodway fringe"
means those portions of
				  the floodplains located landward of the encroachment limits.
"High damage potential"
means the flood
				  damage potential associated with the following:
1. Habitable residential buildings and building complexes
				  which include seasonal residential buildings; or
2. Industrial, commercial, agricultural, recreational and
				  other similar buildings or building complexes, which, if inundated by flooding,
				  would result in high public damages as determined by the department or which
				  contain high-value equipment or contents that are not easily removed; or
3. Public buildings or building complexes, which, if
				  inundated by flooding, would result in high public damages as determined by the
				  department.
"Low damage potential"
means all buildings,
				  building complexes or floodplain uses not defined as maximum or high damage
				  potential where such structures are designed in a manner that inundation by
				  flood waters results in minimal damage to the structure and its contents. Such
				  structures include but are not limited to the following: detached residential
				  garages, sheds, park shelters, buildings used for storage of equipment or crops
				  that can be easily removed, and buildings used as temporary shelter for
				  livestock.
"Major water source"
means the same as
				  defined in 567-65.1 (459,459B).
"Manure storage structure"
means the same as
				  defined in 567-65.1 (459,459B).
"Maximum damage potential"
means the flood
				  damage potential associated with hospitals and like institutions; buildings or
				  building complexes containing documents, data, or instruments of great public
				  value; buildings or building complexes containing materials dangerous to the
				  public or fuel storage facilities; power installations needed in emergency or
				  buildings or building complexes similar in nature or use to those listed
				  above.
"Minimum level of flood protection"
means
				  the elevation corresponding to the water surface profile of the regulatory
				  flood associated with a damage potential classification listed in these rules
				  plus any freeboard specified in these rules.
"Mobile home"
means a structure,
				  transportable in one or more sections, which is built on a permanent chassis
				  and designed to be used with or without a permanent foundation when connected
				  to the required utilities. It does not include recreational vehicles or travel
				  trailers.
"Nominated stream"
means the stream or water
				  source named in the petition described in 567-Chapter 72 that seeks designation
				  of a stream as a protected stream.
"Permanent storage"
means the volume of
				  water expressed in acre-feet which is stored upstream from a dam or in an
				  impoundment up the level of the principal outlet works of the structure.
"Probable maximum flood"
means the flood
				  that may be expected from the most severe combination of critical
				  meteorological and hydrologic conditions that are reasonably possible in the
				  region, and is derived from probable maximum precipitation, the theoretical
				  greatest depth of precipitation for a given duration that is physically
				  possible over a particular drainage area at a certain time of year. The
				  probable maximum precipitation within designated zones in Iowa has been
				  determined by the National Weather Service. The probable maximum flood for any
				  location within Iowa is determined by the department.
"Protected stream"
means a stream designated
				  by the department as a "protected stream" in 567-Chapter 72.
"Public damages"
means costs resulting from
				  damage to roads and streets, sewers, water mains, other public utilities and
				  public buildings; expenditures for emergency flood protection, evacuation and
				  relief, rehabilitation and cleanup; losses due to interruption of utilities and
				  transportation routes, and interruption of commerce and employment.
"Q100," "Q50," "Q25," "Q15," "Q10,"
et
				  cetera, means a flood having a 1, 2, 4, 7, 10, et cetera, percent chance of
				  being equaled or exceeded in any one year as determined by the
				  department.
"Regional flood"
means a flood
				  representative of the largest floods which have been observed on streams in
				  Iowa.
"Repair and maintenance of a drainage district
				  ditch"
means the restoration of the original grade line,
				  cross-sectional area, or other design specifications of a drainage district
				  ditch lawfully established as part of a drainage district formed and operating
				  under the provisions of Iowa Code chapter 468.
"Road projects"
means the construction and
				  maintenance of any bridges, culverts, road embankments, and temporary stream
				  crossings.
"Rural areas"
means any area not defined or
				  designated as an urban area.
"Seasonal homes"
means residential buildings
				  or building complexes which are not used for permanent or year-round human
				  habitation.
"Stream"
means a water source that either
				  drains an area of at least two square miles or has been designated as a
				  protected stream in 567-Chapter 72.
"Temporary storage"
means the volume of
				  water expressed in acre-feet which may be stored upstream from a dam or in an
				  impoundment above the level of the principal outlet works.
"Urban areas"
means incorporated
				  municipalities.
"Water source"
means the same as defined in
				  567-65.1 (459,459B).