Climate Resiliency - Frequently Asked Questions

Department of City Planning


BoroughCitywide


Climate Resiliency Initiatives - Frequently Asked Questions

General

What are flood zones?
Flood zones are land areas identified by the Federal Emergency Management Agency (FEMA) on Flood Insurance Rate Maps (FIRMs). Each flood zone describes a land area in terms of its risk of flooding. FEMA’s FIRMs are created through an extensive mapping process and take into account many factors, including the types and strength of storms that historically have affected the area and the onshore and offshore topography. For the latest developments in the mapping process please see section below.

What is the status of the FEMA mapping process?
FEMA is in the process of updating the Flood Insurance Rate Maps (FIRMs) for New York City and issued Preliminary FIRMs in December 2013 as part of this process. In 2015, FEMA issued revised Preliminary FIRMS with minor changes. Prior to this update process, FEMA had not substantially revised the FIRMs for New York City since they were first established in 1983, though the maps were minimally updated in 2007. For most areas of the city, the Preliminary FIRMs show a dramatic increase in the size of the 1% annual chance floodplain as well as the height of flooding from the 1% annual chance flood.

To ensure the accuracy of the updated Preliminary FIRMS, the City hired an engineering team to review the maps. The City’s team found errors in FEMA’s modeling that overestimate the size of the 100-year floodplain and the height of the Base Flood Elevations. Consequentially, the City appealed FEMA’s Preliminary FIRMS. In October 2016, FEMA announced that the City won its appeal of the Preliminary FIRMs and has agreed to revise New York City’s flood maps. For now, the more restrictive of either the 2015 PFIRMs or the 2007 FIRMS are used for building code and zoning purposes, while the 2007 FIRMs remain in use for flood insurance.

For more information on the map update process, visit www.nyc.gov/floodmaps.

For more information on FEMA’s maps, visit FEMA’s Region 2 Website at www.region2coastal.com or call a FEMA Map Specialist at 1-877-FEMA MAP (1-877-336-2627).

Are City evacuation zones different than FEMA flood zones?
Yes, evacuation zones and FEMA flood zones are different. New York City's hurricane contingency plans are based on six evacuation zones (labeled zones 1 through 6). To find out if you live in a hurricane evacuation zone, use the Hurricane Evacuation Zone Finder at www.nyc.gov/knowyourzone, or call 311. FEMA flood zones are used to determine flood insurance rates as well as flood resistant construction requirements.

How do I know if I am in a flood zone?
FEMA creates and updates flood maps (called Flood Insurance Rate Maps, or FIRMs) for New York City and has created a website to provide the most up to date information regarding flood risk for particular locations throughout the five boroughs. On FEMA’s website, you can view the latest flood risk information for your property, as shown on the most current FIRMs (the 2013 Preliminary FIRMs). To find this information for your specific address, go to www.region2coastal.com/sandy/table or FloodHelpNY.org To view the maps for the entire city or a specific neighborhood, go to FEMA’s online Map Viewer.

What is the difference between A, Coastal A, V, and Shaded X zones?
FEMA identifies different flood zones to differentiate potential flood risks. A zones, Coastal A zones and V zones are all part of the 100-year floodplain, or the area where there is 1% chance of flooding in any given year. Within this area, FEMA requirements for the mandatory purchase of flood insurance and NYC Building Code requirements for flood-resistant construction apply.

A Zone: A portion of the area subject to flooding from the 1% annual chance flood. These areas are not subject to high velocity wave action but are still considered high risk flooding areas. In A Zones, NYC Building Code requires buildings to be elevated or flood-proofed based on the Base Flood Elevation identified on the FEMA’s firms. A Zones can also be shown as AE or AO on FEMA’s FIRMs for New York City.

Coastal A Zone: A sub-zone of the A Zone where wave heights are expected to be between 1.5 and 3 feet high. This zone is indicated by the Limit of Moderate Wave Action (LiMWA) line on the latest FEMA FIRMs. This zone has been mapped by FEMA for the first time in New York City. View the FEMA video on the LiMWA line and Coastal A Zone.

V Zone: portion of the 1% annual chance floodplain subject to high velocity wave action (a breaking wave 3 feet high or larger). V Zones are subject to more stringent building requirements than other zones because of the damaging force of waves. V Zones can also be shown as VE on FEMA’s FIRMs.

Shaded X Zone: The area of moderate flood risk outside the regulatory 1% annual chance flood but within the limits of the 0.2% annual chance flood level (the 500-year floodplain). There are no current NYC Building Code or FEMA flood insurance purchase requirements for buildings in this zone.

What is the Base Flood Elevation?
FEMA’s flood maps identify the expected height of flooding from the 1% annual chance flood for each zone, known as the Base Flood Elevation. The Base Flood Elevations are denoted in the datum NAVD 88, which represents the number of feet above mean sea level in that datum.

What are flood resistant construction standards?
Flood-resistant construction standards are minimum requirements for construction of new buildings and substantial improvements in the 1% annual chance floodplain established by the Federal Emergency Management Agency (FEMA) and NYC Building Code. A building is considered substantially improved if the cost of the improvement exceeds 50% of the building’s market value. These standards require that buildings located within the A-Zone, should be wet-floodproofed or dry-floodproofed depending on the building’s use. Federal standards require residential use to be elevated above expected flood levels and allow only commercial or mixed-used buildings the option of dry floodproofing. If a building is wet-floodproofed, it needs flood-resistant materials to be used under the flood elevation. Any mechanical, electrical, and plumbing equipment must be located above anticipated flood levels. If dry-floodproofed, buildings need to be designed to withstand the pressure of water, by sealing the building’s exterior and using removable barriers at all entrances below the expected level of flooding. Buildings located within the V-Zone, need to be elevated and designed to resist the pressure of waves, independently of the use. Flood-resistant construction standards are defined in Appendix G of the NYC Building Code and the American Society of Civil Engineers’ Flood Resistant Design and Construction manual, referred to as ASCE 24.

For more information on recent changes to the Building Code visit the Department of Building’s website on rebuilding after Sandy.

V-Zone Wet-floodproofing
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A-Zone Wet-floodproofing
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A-Zone Dry-floodproofing
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How do flood resistant construction standards interact with zoning?
In many instances, zoning regulations or conflicts between zoning and Building Code requirements would make it difficult, or in some cases impossible, for owners to build or retrofit to flood-resistant construction standards. Flood Resilience Zoning is one part of a wide range of efforts by the City to recover from Hurricane Sandy, promote rebuilding, and increase the city’s resilience to climate-related events, including coastal flooding and storm surge. The Flood Resilience Zoning Text Amendment, adopted in October 2013, removes zoning barriers to reconstructing storm-damaged properties and allows new and existing buildings to comply with new, higher flood elevations issued by FEMA and new requirements in the Building Code. To help ensure that the streetscape remains vibrant and engaging as buildings are rebuilt to meet new flood protection standards, the amendment permits buildings to grade up gradually to flood elevations by raising their yards, and requires elevated buildings to provide simple but effective streetscape enhancements such as stair turns, plantings, and porches to ensure they maintain visual connectivity with the street.

Through other work on Climate Resiliency, the Department of City Planning is actively working with community members and property owners in specific neighborhoods – in residential, commercial and manufacturing areas – throughout the city’s floodplain to tailor strategies to the needs and opportunities of the area.

Is the elevation on the latest FEMA map the height that buildings should be raised to?
The Base Flood Elevation (BFE) on FEMA’s FIRMs and PFIRMs is a measurement of height above a fixed point in the ground, not a measurement of flood height above the level of the ground at your property. The BFEs on the Preliminary FIRMs are referenced in a vertical datum called North American Vertical Datum of 1988 (NAVD 88). To determine the height that your building must be raised above the ground, you need to subtract the elevation of the ground from the BFE. The NYC Building Code also requires an additional 1 to 2 feet of elevation as a measure of safety, called freeboard (see below). The freeboard, in addition to the BFE, is called the Design Flood Elevation (DFE).

For more information about vertical datums, visit FEMA Region 2 website.

What is freeboard?
“Freeboard” is the practice of elevating a building’s lowest floor above the Base Flood Elevation (BFE) by a small additional height, typically 1 to 2 feet above FEMA minimum height requirements, depending on building type (2 feet for single and two- family residences and 1 foot for most other buildings). The benefits of freeboard include an additional margin of safety to protect against more severe storms and increased future flood risks from rising sea levels. Additionally, FEMA recognizes that freeboard significantly reduces flood risk and provides substantial reductions in flood insurance premiums.

What is flood insurance?
Standard homeowners’ insurance does not include protection against flood damages. However, for homes within the 1% annual chance floodplain there is at least a 1 in 4 chance of flooding during the life of a 30-year mortgage. FEMA administers the National Flood Insurance Program (NFIP) and establishes premiums and standards for NFIP policies, which are sold to homeowners, renters, and business owners through private insurance agents. Properties with a federally-backed mortgage located in the 1% annual chance floodplain are required to purchase flood insurance. Properties outside the 1% annual chance floodplain can also purchase flood insurance, but it is not mandatory.

As discussed above, FEMA is in the process of updating the city’s Flood Insurance Rate Maps (FIRMs), which are used to establish insurance requirements and premiums. Following the City’s successful appeal in October 2016, insurance rates are still based on 2007 FIRMS; 2015 Preliminary FIRMs are used for building code, zoning, and planning purposes. However, once FIRMS are updated and adopted, properties may have higher flood insurance premiums and may be required to purchase a flood insurance policy.

Additionally, the Biggert-Waters Flood Insurance Reform Act of 2012 was passed by the U.S. Congress in July 2012 with the goal of making the national program more financially stable by reducing the amount of public subsidy it requires. While subsequent legislation—the Homeowners Flood Insurance Affordability Act of 2014—slowed increases to premium rates, policyholders will face increased premiums over time that reflect the full risk to their properties. Property owners can qualify for reduced insurance premiums by bringing their building into full compliance with current standards for flood resistant construction. FEMA provides information about the impact of these legislative changes on your flood insurance in this brochure.

In summary, the expansion of the flood zones as part of the flood map update process along with legislative changes to the NFIP will mean that more property owners will be required to purchase flood insurance and that many will see increases in flood insurance rates over time.

For additional information about flood risk and insurance, visit FEMA’s national website www.floodsmart.gov or call FEMA's flood insurance hotline for New York at: 1-888-435-663.

What does “resiliency” mean in the context of flood risk?
Resiliency is the ability to withstand and recover from disruptive events, such as a coastal storm. Resiliency also refers to the capacity of a community to adapt to change while maintaining its vibrancy, livability, and equity. In the context of flood risk, a resilient neighborhood is one where:

Residents know their flood risk and how to prepare in the event of a storm;

Property owners are able to adapt their buildings to minimize damage and disruption from flooding through strategies that also meet the community’s goals for neighborhood character and a quality streetscape;

Infrastructure systems can withstand significant flood events and offer some protection from flooding while also working for everyday conditions;

Community stakeholders understand potential future conditions due to climate change and are actively engaged in planning for the future.

Resilient Neighborhoods

How will the Resilient Neighborhoods initiative make neighborhoods in the flood zone more resilient?
Resilient Neighborhoods is part of the City’s broad set of initiatives as laid out in #OneNYC and A Stronger, More Resilient New York report to reduce risks and build resiliency through strengthening coastal defenses, improving buildings, protecting infrastructure, and making neighborhoods safer and more vibrant. Through the Resilient Neighborhoods study, the Department of City Planning is working closely with community groups to develop targeted strategies to increase resiliency to coastal flooding and support neighborhood vitality. This work will seek to implement zoning and land use changes that will make buildings and neighborhoods more resilient to future flood damage while also meeting the communities’ needs for housing, access to services, and design.

The Department is working with the Office of Recovery and Resiliency and other City agencies to establish a guiding framework for strengthening neighborhood resiliency over time that will ensure coordination between land use planning, rebuilding, and infrastructure investment.

How does the Resilient Neighborhoods initiative relate to other city, state and federal resiliency projects?
Resilient Neighborhoods is one of the City’s broad set of initiatives as laid out #OneNYC and A Stronger, More Resilient New York report to reduce risks and build resiliency through strengthening coastal defenses, improving buildings, protecting infrastructure, and making neighborhoods safer and more vibrant. These plans identified the need for additional study of locally-specific strategies to increase the resiliency of communities through zoning and land use tools.

The Department is working with the Office of Recovery and Resiliency and other agencies to coordinate the implementation of resiliency projects within each study area. This work will build off of previous and ongoing planning efforts, including the New York City Build it Back program run by the Housing Recovery Office, New York State’s New York Rising Community Reconstruction Program, and the U.S. Housing and Urban Development’s Rebuild by Design Competition.

Resilient Retail

Can commercial properties purchase flood insurance?
Yes, flood insurance is available to all commercial property owners and tenants, and business property owners located within the V- and A- zones of the floodplain (1% annual chance floodplain) holding mortgages from federally-regulated lenders may be required to hold National Flood Insurance Program flood insurance. Additionally, lending institutions may also insist that properties purchase private flood insurance coverage in excess of the NFIP maximum, in order to more fully cover property and contents recovery costs. The National Flood Insurance Program offers commercial property owners coverage for up to $500,000 on Building Property and up to $500,000 for Personal Property, largely defined as the contents of the business. Businesses renting their space may purchase contents coverage as well. NFIP also offers their Preferred Risk Policies to owners of non-residential properties if they are located within Moderate- to Low-risk areas. Property owners within High Risk flood areas will receive policies adjusted to match their exposure to flood risk. A full list of what Building and Personal property is covered for commercial policy holders can be found here.

Note that financial losses due to business interruption or loss of use of insured items are not covered by NFIP.

For more information on insurance rates for commercial properties, visit National Flood Insurance Program.

For additional information about flood risk and insurance, visit FEMA’s national website www.floodsmart.gov or call FEMA's flood insurance hotline for New York at: 1-888-435-6637

What does business resiliency mean in the context of flood risk?
Resilient businesses are able to recover quickly from flood events with minimal financial and time costs related to structural building damage or loss of inventory. They have also worked to develop operational strategies for day-to-day business operations, inventory storage, and data management that reinforce targeted retrofits aimed at minimizing physical exposure to flood risk. Additionally, local merchant and community groups understand potential future conditions due to climate change and are actively engaged in planning for the future.

How has the City’s zoning text changed to help commercial property owners?
Flood Resilience Zoning is one part of a wide range of efforts by the City to recover from Hurricane Sandy, promote rebuilding, and increase the city’s resilience to climate-related events, including coastal flooding and storm surge. The Flood Resilience Zoning Text Amendment, adopted in October 2013, removes zoning barriers to reconstructing and retrofitting storm-damaged properties and allows new and existing buildings to comply with new, higher flood elevations issued by FEMA and new requirements in the Building Code. The zoning adjustments allow commercial buildings to make resiliency investments, such as elevating mechanical systems, while also promoting an active streetscape, such as through encouraging dry floodproofing of ground floor commercial spaces. DCP is continuing to explore opportunities to help business owners rebuild resiliently.

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