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Floodplain Management

Development Services | 211 Jackson Street | Bastrop, Texas 78602 | (512) 581-7176

 

Hours of Operation:  Monday through Friday 8:00 a.m. - 4:00 p.m.

Preliminary Flood Insurance Rate Map and

Flood Insurance Study Report

 

The Federal Emergency Management Agency (FEMA) has presented Bastrop County with preliminary copies of the Flood Insurance Rate Map (FIRM) and Flood Insurance Study (FIS) Report dated February 11, 2021 for Bastrop County, Texas and incorporated areas.  The FIS Report describes the flood hazard information updates made and the source information used.  FEMA only revised those FIRM panels with updated flood hazard information.  The preliminary FIRM panels can be viewed and/or downloaded from the FEMA portal or hard copies can be viewed in the Development Services Office.   For additional information, please contact Marlene Flores, Bastrop County Floodplain Administrator, at 512-581-7159.

Texas Water Development Board (TWDB) Watershed Studies Project 

 

TWDB has funded a multi-year project to identify Bastrop County flood hazards, develop mitigation projects and update FEMA Firm Panel Maps.  Additional information was provided at the 01/25/2023 Public Meeting.

Base Level Engineering estBFE Viewer Now Available

 

In 2018, FEMA released Base Level Engineering (BLE) data that included Bastrop County.  The Base Level Engineering production approach combines high-resolution ground elevation data, and modeling technology advancements to create engineering models and flood hazard data.  This information provides additional risk assessment resources where there are currently gaps in the current national flood hazard data inventory and the Flood Insurance Rate Maps (FIRMs).  FEMA has developed an Estimated Base Flood Elevation Viewer that can be used to determine your flood risk and a FEMA Factsheet on the Viewer.  They also published a Factsheet on Base Level Engineering. 

Building & Floodplain Basics
 
Development Permits Required
A development permit is required for all development in the unincorporated areas of Bastrop County.  An application for a development permit must be submitted before you build or place a structure on your property.  This includes manufactured homes, recreational vehicles, and tiny homes.  There are three types of development permit:
  • "Class A" permits are issued for all development outside the mapped 100-year floodplain,
  • "Conditional Class A" permits are issued for all development outside the mapped 100-year floodplain but on property within the 100-year floodplain, and
  • "Class B" are issued for all development of property that lies partially or wholly within the mapped 100-year floodplain.

Applications, Fee Schedule, and Information may be obtained from our offices. 
 
What is Development?
Development is any soil disturbing activity, and is defined in the Bastrop County Flood Damage Prevention Order as any man-made change in improved and unimproved real estate, including, but not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations or storage of equipment or materials.

What is a Floodplain?
A floodplain is a geographic area subject to flooding; land adjacent to waterway necessary to contain a flood. Floodplains are associated with rivers, lakes, streams, channels, and small creeks that are normally dry most of the year.

Floodplain Regulations in Bastrop County
The Bastrop County Flood Damage Prevention Order contains regulations designed to protect property and the public health and safety. All development must adhere to federal floodplain regulations (CFR 44).
 
Bastrop County Floodplain Management is using the best available data to insure that all development is relatively safe from flooding.  Flood Prone Areas are identified by several different sources including
  • Flood Insurance Rate Maps or FIRMs, which identify Special Flood Hazard Areas
  • Base Level Engineering or estBLE which identify Supplemental Flood Hazard Areas
  • Flood Studies which identify Community Determined Flood Hazard Areas based on watersheds
  • Letters of Map Change which contain very specific areas
  • and/or repetitive loss areas.

Building in a Floodplain
Before you file an application to develop property within the floodplain, you will need to hire a Surveyor who will certify that the proposed construction will meet the requirements of the Bastrop County Flood Damage Prevention Order. Please contact our office to schedule a consultation to discuss your plans and to determine the best course of action to assure that your property will be reasonably safe from flooding.

Additions and Decks
If I build an addition or deck outside my building, do I need to raise my existing building two-feet above the base flood elevation?
Any addition must comply with all floodplain regulations. If the value of the addition, remodel, or repairs of the home or business exceeds 50% of the value of the existing:
  • Residential home, the existing structure(s) must be elevated two-feet above the base flood elevation.
  • Non-Residential, the existing structure(s) must be either elevated or flood-proofed two-feet above the base flood elevation.

What are the penalties if I don't secure all my permits?
  • You would not be able to occupy or use your building or development until you receive all required permits.
  • You may be fined up to $500 per day of offense (each day constitutes a separate offense).
  • The County may require the removal of the improvements constructed without permits.

Mandatory Flood Insurance Requirement
The mandatory purchase requirement applies to all forms of federal or federally related financial assistance for buildings located in a Special Flood Hazard Area. This requirement affects loans and grants for the purchase, construction, repair, or improvement of any publicly or privately owned building in the SFHA. This includes machinery, equipment, fixtures, and furnishings contained in such buildings.

How are premiums calculated?
A number of factors determine the premium rates for flood insurance coverage. They include the amount of coverage purchased, location, age of the building, building occupancy, the design of the building, and, for buildings in SFHAs, the elevation. The only buildings in Zones B, C, and X which are eligible for preferred risk coverage at a pre-determined, reduced premium rate are single-family and 1-4 family dwellings. For these exceptions, there are certain loss limitations depending on the amount of insurance purchased.

What constitutes "substantial improvement" or "substantial damage?"
"Substantial improvement" means any rehabilitation, addition, or other improvement of a building when the cost of the improvement equals or exceeds 50 percent of the market value of the building before start of construction of the improvement. The term includes buildings which have incurred "substantial damage," or damage of any origin sustained by a building when the cost of restoring the building to its pre-damaged condition would equal or exceed 50 percent of the market value of the building before the damage occurred. Substantial damage is determined regardless of the actual repair work performed.

Substantial improvement or damage does not, however, include any project for improvement of a building 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. Also excluded from the substantial improvement requirement are alterations to historic structures as defined by the NFIP.


Frequently Asked Questions
  • FEMA defines a floodplain as any land area susceptible to being inundated by floodwaters from any source.
  • The Flood Insurance Rate Map (FIRM) shows areas within the 100-year flood boundary, which are termed "Special Flood Hazard Areas (SFHAs)." A "100-year flood" does not refer to a flood that occurs once every 100 years, but refers to a flood level with a 1 percent or greater chance of being equaled or exceeded in any given year.  The SFHAs may be further subdivided into insurance risk rate zones (see below). Areas between the 100-year and 500-year flood boundaries are termed "moderate flood hazard areas." The remaining areas are above the 500-year flood level and are termed "minimal flood hazard areas."

    Historically, about one-third of claims paid by the NFIP are for flood damage tin areas identified as having only "moderate" and "minimal" risk of flood.  Flooding in these often is the result of inadequate local drainage 25 systems, and such flooding sources with small drainage areas are generally not identified on FIRMS, but are a part of Flood Prone Areas.  The SFHAs are subdivided into flood hazard zones (insurance risk rate zones) according to the following criteria:   

    • Zone A:  SFHAs subject to inundation by the 100-year flood.  Because detailed hydraulic analyses have not been performed, no base flood elevation or depths are shown. Mandatory flood insurance purchase requirements apply.  
    o Estimated Base Level Engineering allows Bastrop County to determine the base flood elevations and flood depths for areas on the FIRM designated as Zone A.

    • Zones AE:  SFHAs subject to inundation by the 100-year flood determined in a Flood Insurance Study by detailed methods. Base flood elevations are shown within these zones. Mandatory flood insurance purchase requirements apply. (Zone AE is used on new and revised maps in place of Zones A1-30.) 

    • Zone AH:  SFHAs subject to inundation by 100-year shallow flooding (usually areas of ponding) where average depths are between one and three feet. Base flood elevations derived from detailed hydraulic analyses are shown in this zone.  Mandatory flood insurance purchase requirements apply.

    • Zone AO:  SFHAs subject to inundation by 100-year shallow flooding (usually sheet flow on sloping terrain) where average depths are between one and three feet. Average flood depths derived from detailed hydraulic analyses are shown within this zone.  Mandatory flood insurance purchase requirements apply. 

    • Zone X:  These areas have been identified in the community flood insurance study as areas of moderate or minimal hazard from the principal source of flood in the area.  However, buildings in these zones could be flooded by severe, concentrated rainfall coupled with inadequate local creates areas of high flood risk within these rate zones.  Flood insurance is available in participating communities but is not required by regulation in these zones.
    o Estimated Base Level Engineering allows Bastrop County to determine the base flood elevations and flood depths for some areas on the FIRM designated as Zone X, and structures developed in these areas will now be required to elevate 2’ above the base flood elevation.
     
  • Special flood hazard areas are determined using statistical analyses of records of river flow, storm tides, and rainfall; information obtained through consultation with the community; floodplain topographic surveys; and hydrologic and hydraulic analysis. The detailed FIS covers those areas that are subject to flooding from rivers and streams, along coastal areas and lake shores, or in shallow flooding areas, but do not include areas of less than one square mile.
  • You can request this information by email, phone, or deliver requests to the County Floodplain Administrator.  To assure we have the correct location, please include the Bastrop Central Appraisal District’s Property ID number, the physical address, and legal description of the property with your request.

    You may also use the Estimated Base Level Engineering website.  The website will allow you determine if your development will be within a flood prone area and to print a report with flood depths and an estimated Base Flood Elevation (BFE).   If the location of your development is within Zone AE, the site will direct you to the FEMA Map Service Center.  Digital versions and images of flood maps can be viewed and printed from the Map Service Center also.  The Map Service Center allows users to create a Firmette at no cost.  A Firmette is a section of the flood hazard map at 100% scale that can be printed on standard paper sizes.
     
  • The floodway includes the channel of a river and the adjacent floodplain that state standards specify smaller allowable increases.  FEMA requires the community to designate a floodway to avoid the possibility of significantly additional rise in base flood elevations.
  • Floodplain in areas that have been identified by different sources including but not limited to FIRMs (Special Flood Hazard Areas), Base Level Engineering (BLE) (Supplemental Flood Hazard Areas), Flood Studies (Community Determined Flood Hazard Areas), Letters of Map Change, and/or repetitive loss areas.
  • Yes, but the Bastrop County Flood Damage Prevention Order has provisions with specific requirements for each type of structure that is built within a flood prone area.  

    Please contact our office to schedule a consultation to review your plans and to determine the best course of action to assure that your project will be reasonably safe from flooding.

    A surveyor or engineer can certify that the proposed construction will meet the requirements of the Bastrop County Flood Damage Prevention Order by preparing an elevation certificate.  Elevation certificates are required for residential development.
  • A floodway is the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height.  There are provisions in the Flood Damage Prevention Order that may allow development in the floodway.  Contact the Floodplain Administrator for details.
  • Three procedures have been established for changing or correcting a flood map.  They are called collectively Letters of Map Change (LOMC) and include:
    • a Letter of Map Amendment (LOMA) 
    • a Letter of Map Revision (LOMR) 
    • and a physical map revision.  
     

    • A LOMA is the result of an administrative procedure in which the Federal Insurance Administrator reviews scientific or technical data submitted by the owner or lessee of property who believes the property has incorrectly been included in a designated SFHA. A LOMA amends the currently effective FEMA FIRM map and establishes that a property is not located in a SFHA.

      Although FEMA may issue a LOMA, it is the lending institution's prerogative to require flood insurance as a condition of its own beyond the provisions of the Flood Disaster Protection Act of 1973 before granting a loan or mortgage. Those seeking a LOMA should first confer with the affected lending institution to determine whether the institution will waive the requirement for flood insurance if a LOMA is issued. If so, the policyholder may cancel flood insurance coverage and obtain a premium refund.

       

      In general, the scientific or technical data needed to effect a map amendment includes certified topographic data and/or hydrologic and hydraulic analyses to support the request for amendment or revision.

       

    • A LOMR is an official revision to the currently effective FEMA FIRM map. It is used to change flood zones, floodplain and floodway delineations, flood elevations, and planimetric features. All requests for LOMR's must be made to FEMA through the chief executive officer of the community, since it is the community that must adopt any changes and revisions to the map. A LOMR is usually followed by a physical map revision.