Glossary of Regional Flood Planning Terms and Acronyms
Source: Texas Water Development Board / Title 31 Texas Administrative Code Chapter 361
1.0% annual chance flood event – Flood event having a 1.0% chance of being equaled or exceeded in any given year, also referred to as the base flood or 100-year flood.
0.2% annual chance flood event – Flood event having a 0.2% chance of being equaled or exceeded in any given year, also referred to as the 500-year flood.
Board – the governing body of the Texas Water Development Board.
Executive Administrator (EA) – The Executive Administrator of the TWDB or a designated representative.
FEMA – Federal Emergency Management Agency
FIRM – Flood Insurance Rate Map
Flood – A general and temporary condition of partial or complete inundation of normally dry land area from overflow of inland or tidal waters or from the unusual and rapid accumulation or runoff of surface waters from any source.
Flood-prone – Areas with known risk of flooding primarily during storm events either from existing inundation maps, studies, and/or historic knowledge of flood events. Flood-prone areas may include, but are not limited to, the floodplain, the floodway, the flood fringe, wetlands, riparian buffers, or other areas adjacent to the main channel.
Floodplain – That area of land subject to periodic inundation by floodwaters.
Floodplain management – The operation of an overall program of corrective and preventative measures for reducing flood damage.
Flood Mitigation – The implementation of actions, including both structural and non-structural solutions, to reduce flood risk to protect against the loss of life and property.
Flood Management Evaluation (FME) – A proposed flood study of a specific, flood-prone area that is needed in order to assess flood risk and/or determine whether there are potentially feasible FMSs or FMPs.
Flood Management Strategy (FMS) – A proposed plan to reduce flood risk or mitigate flood hazards to life or property. A flood management strategy may or may not require associated Flood Mitigation Projects to be implemented.
Flood Mitigation Project (FMP) – A proposed project, both structural and non-structural, that has a non-zero capital costs or other non-recurring cost and that when implemented will reduce flood risk, mitigate flood hazards to life or property.
Flood Planning Region (FPR) – A geographic area designated by the Board pursuant to Texas Water Code §16.062.
Flood Risk – Generally describes the hazard from flood events to life and property, including the likelihood of a hazard occurring; the magnitude of the hazard; the number of people and properties exposed to the hazard; and the vulnerability of the people and properties exposed to the hazard.
Flood Risk Map – A map that shows flood risk for Texas communities at some level of detail using best available data.
GIS – Geographic Information System
GLO – General Land Office
HUC – Hydrologic Unit Code level (e.g., HUC8) as delineated by the United States Geological Survey.
Hydrologic and Hydraulic Model – Mathematical model created utilizing computer software that simulates rainfall runoff flow to estimate the extent of water levels and flooding and to test potential ways to reduce flood risk.
Nature-based flood mitigation – Mitigation approaches involving the use of natural features, materials, and processes to reduce the risk and impacts of flooding.
Neighboring area – means any area, including but not limited to upstream and downstream areas, potentially affected by the proposed FMP.
Negative Effect – An increase in flood-related risks to life and property, either upstream or downstream of the proposed project. The RFPG may adopt a standard that is more restrictive than the standard provided in TWDB guidance.
Planning Group Sponsor – A political subdivision designated by the Regional Flood Planning Group as authorized to receive funds for developing or revising regional flood plans.
Political Subdivision – County, city, or other body politic or corporate of the state, including any district or authority created under Art. 3 § 52 or Art. 16 § 59 of the constitution and including any interstate compact commission to which the state is a party and any nonprofit Water Supply Corporation created and operating under Ch. 67.
Potentially feasible flood management strategy or potentially feasible flood mitigation project – a FMS or FMP that is permittable, constructible, economically viable, and implementable.
Regional Flood Plan (RFP) – The plan adopted or amended by a Regional Flood Planning Group pursuant to Texas Water Code §16.062 (relating to Regional Flood Plans) and this chapter.
Regional Flood Planning Group (RFPG) – A group designated by the Board that develops a Regional Flood Plan, pursuant to Texas Water Code §16.062.
Residual Risk – The remaining flood risk in an area after the completion of a FMS or FMP or set of FMSs or FMPs that reduce flood risk in that same area.
State Flood Plan (SFP) – The most recent State Flood Plan adopted or amended by the Board under Texas Water Code §16.061 (relating to State Flood Plan).
State Flood Planning Database – A database to be developed and maintained by the TWDB that stores data related to Flood Planning. It is used to collect, analyze, and disseminate regional and statewide Flood Planning data.
State Population Projections – Population projections contained in the most recently adopted State Water Plan as further assembled geographically based on HUC 8 watersheds or other appropriate flood-related geographic features determined by the TWDB.
TWC – Texas Water Code
TWDB – Texas Water Development Board