City of Largo Flood Related Terms and Conditions (per Ordinance 2009-49) back  
Date of Record: June 24, 2011

The following list is for informational purposes only. To obtain the most current information, please contact the City of Largo Community Development Department at (727) 587-6749, or submit an inquiry online.



base flood:
A flood having a one percent chance of being equaled or exceeded in any given year. The base flood is also known as the regulatory base flood or the 100 year flood. The base flood is a statistical concept used to ensure that all properties subject to the National Flood Insurance Program are protected to the same degree against flooding.

flood or flooding: A general and temporary condition of partial or complete inundation of normally dry land areas from:

(1) The overflow of inland or tidal waters.

(2) The unusual and rapid accumulation or runoff of surface waters from any source.

Flood Insurance Rate Map (FIRM): The official map on which the FEMA has delineated both the special areas and the risk premium zones applicable to the community.

flood plain: Land which will be inundated by floods known to have occurred or reasonably characteristic of what can be expected to occur from the overflow of inland or tidal waters and the accumulation of runoff or surface waters from rainfall.

flood way: The channel of a natural stream or river and portions of the flood plain adjoining the channel, which are reasonably required to carry and discharge the floodwater or flood flow of any natural stream or river.

height: The vertical distance of a structure measured from the average elevation of the finished grade to the highest elevation of the structure including any antennas or other attachments for all platted or unplatted lots. For all properties located within a Special Flood Hazard Zone which requires the first floor elevation to be one (1) foot above the base flood elevation, building height shall be measured from the first floor elevation of the structure to the highest elevation of the structure.

new construction: Structures for which the start of construction commenced on or after the effective date of the Largo Comprehensive Development Code (9.3 MB). Additionally, new construction means, for the purposes of determining insurance rates, structures for which the start of construction commenced on or after the effective date of an initial FIRM or after December 31, 1974, whichever is later, and includes any subsequent improvements to such structures. For flood plain management purposes, new construction means structures for which the start of construction commenced on or after the effective date of flood plain management regulations adopted by the City of Largo, Florida, and includes any subsequent improvements to such structures.

one hundred (100) year flood: See "base flood."

replacement cost depreciated: The value of the structure as determined in accordance with FEMA's Floodplain Management Requirements.

start of construction, regulatory:


(1) For regulatory purposes in areas that are not floodprone, start of construction is the date the building permit was issued.

(2) In floodprone areas other than those covered by the National Flood Insurance Program, start of construction includes the initiation of substantial improvement and begins the actual day of construction.

(3) For FEMA purposes, start of construction (for other than new construction or substantial improvements under the Coastal Barrier Resources Act [Pub. L. 97348]), includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition, placement, or other improvement was within 180 days of the permit date. The actual start means either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or the placement of a manufactured home on a foundation. Permanent construction does not include land preparation, such as clearing, grading, and filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers, or foundations, or the erection of temporary forms; nor does it include the installation on the property of accessory buildings such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual start of construction means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not that alteration affects the external dimensions of the building.

substantial damage: Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed fifty (50) percent of the market value of the structure before the damage occurred.

substantial improvement: Any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds on a cumulative basis fifty (50) percent of the replacement cost depreciated of the structure before the start of construction of the improvement. This term includes structures which have incurred substantial damage, regardless of the actual repair work performed. The term does not, however, include either (1) any project for improvement of a structure to correct existing violations of state or local health, sanitary or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions or (2) any alteration of an historic structure, provided that the alteration will not preclude the structure's continued designation as a historic structure.


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