Learn About Norwalk's Flood Zone

What is a Flood Zone?

Flood Zones are geographic areas that FEMA has defined according to varying levels of calculated flood risk.  Any area in Norwalk can experience flooding, but flood hazard zones have a higher risk of flooding and are subject to special regulations and flood insurance requirements. 

In Norwalk, we are susceptible to both riverine and coastal flooding.  While both types of flooding can result in water damage to properties, the amount and type of damage can vary based on your property's location.  Flood mitigation measures can also vary based on the type of flooding expected in an area.

In Norwalk, flooding can occur as a result of heavy rainfall, coastal storm surge, and our development patterns. These typical reasons for flooding will become exacerbated over time as sea-levels rise, coastal storms intensify, and impervious surfaces increase.  FEMA has designated Special Flood Hazard Areas - areas that have special flood, mudflow, or flood related erosions hazards and identified them on Flood Insurance Rate Maps (FIRMS). The map below shows a snapshot of Norwalk's flood zone:

FEMA maps the flood zones in communities across the US - including Norwalk - and identifies areas of varying flood risk on Flood Insurance Rate Maps (FIRMs). FEMA creates FIRMs to inform flood insurance pricing in the National Flood Insurance Program (NFIP) and to guide floodplain management/flood hazard zone regulations for communities.  

FEMA has developed a 'story map' that explains flood concepts and explains the FEMA FIRM maps.   This webpage is focused on Coastal Floodplain Mapping, but is loaded with useful information for all. coastal floodplain pic Opens in new window

Is my property within a Flood Hazard Zone?

Below are links to two external websites that are searchable by street address.  Keep in mind, neither of these two sources of information can predict whether flooding will occur at a property, but they can both be used as tools to assist you in assessing risk. 
floodmap FIRMflood factor logo cube
View the official FEMA FIRM for any property by entering an address in FEMA's map viewer.To learn more about the flood risk for your property, try using the information from Flood Factor.


What should I do if my property is within the flood zone?

If your property is located within a Special Flood Hazard zone, you will need to look more closely at the FEMA FIRM map to determine which flood hazard zone your property is within and if there is base flood elevation (BFE) information in the vicinity of the property.   The BFE is the elevation of surface water that is predicted to result from a flood that has a 1% chance of equaling - or exceeding - that level in any given year.

Depending on your proposed construction and the flood zone your property is within, there will likely be some additional structural requirements, certification documentation, and budget considerations for building in a flood hazard zone. 

The Building Department can inform you of any Building Code requirements for construction within a flood zone. Article 110 of the Zoning Regulations describes the flood zones and related requirements for work within any Flood Hazard Zone within Norwalk.  Refer to the official language in the regulations here.  

Some of the requirements to consider prior to initiating work within a Flood Hazard Zone: 

Structural Requirements

  • Flood vents or break-away walls
  • Finished living space must be constructed at elevations at least one foot above BFE
  • Flood-resistant materials

Documentation Requirements 

  • Proposed flood certification by a licensed professional engineer or architect
  • Final (post-construction) flood certification by licensed professional engineer or architect 
  • Final FEMA elevation certificate (issued by a CT licensed Land Surveyor) when bringing a dwelling into full flood compliance

FEMA Budget/Substantial Improvements

  • FEMA limits the amount of work that can be put into a structure within the flood zone. 
  • The cumulative cost of any repairs, reconstruction, or improvement of a structure cannot exceed fifty percent (50%) of the market value of the structure either before the start of construction of the improvement or repair, or if the structure has been damaged and is being restored, before the damage occurred, including the cumulative cost of improvements taking place after the original effective date of these regulations April 24, 1978. 
  • The FEMA budget is taken into account when the first alteration of any wall, ceiling, floor or other structural part of the building commences, whether or not that alteration affects the external dimensions of the structure. 
  • The budget is cumulative from the first instance of work (post 4/24/78) until the budget has been met. If the entire budget has been used, the home must be made flood compliant to make any more improvements.
  • Click here to learn more about the FEMA policies described above.

**The requirements listed above do not apply to any project for improvement of a structure to comply with existing state or local health, sanitary or safety code specifications which have been previously identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions nor any alteration of a historic structure listed on the National Register of Historic Places or a State Inventory of Historic Places, provided that the alteration will not preclude the structure’s continued designation as a historic structure.**

In Norwalk, we have zoning regulations that apply to properties within the flood zone. In some instances (but not all), your home may be located in an area that is within the flood zone AND the Coastal Area Management Zone. Learn more about the coastal area management zone, here.

Everyone lives in an area with some flood risk—it’s a question of whether you are in a high-risk, low-risk, or moderate-risk flood area.