Flooding has been a pervasive problem throughout history. The NFIP has had
an impact on the problem. New buildings are better protected from damage and
there is greater awareness of the consequences of infringing on floodplains.
However, while the NFIP and participating communities have helped mitigate flood
damage, flooding has certainly not stopped. The reason is that most communities
adopt and enforce only the minimum national and state floodplain management
requirements, which focus on protecting new buildings, not what the impact of
that construction will do to others.
The "No Adverse Impact" (NAI) floodplain management approach is a
concept developed by the Association of State Floodplain Managers (ASFPM) to
address the shortcomings of the typical local floodplain management program.
Rather than looking at the minimum requirements of federal or state programs,
NAI focuses on what communities can do that will actually protect property
and prevent increased flooding, now and in the future. The NAI approach
focuses on planning for and lessening flood impacts resulting from land
use changes (see Figure
6-1). It is essentially a "do no harm" policy that
will significantly decrease the creation of new flood damages. In essence,
NAI means that your neighbor should build in such a way that does not
increase the risk of flooding to your property or others. Examples of
this “wise use” or the “most beneficial use” would
be using the floodplain as dedicated open space for flood storage and
low impact uses such as recreation.
In Oklahoma, the OWRB supports the concept of NAI, and although adopting higher
standard ordinances is strictly voluntary, communities should be aware of the
benefits of doing so. The following article from the Missouri State Emergency
Management Agency Newsletter (vol. 49(4)) gives an overview of why communities
should adopt and consider higher standard ordinances. Adopting a freeboard above
the 1% flood event will provide more protection from flood damage and provide
a cost savings for people that wish to purchase flood insurance.
Two Feet or Not Two Feet? What is the Answer? — L. Scott Samuels,
P.E., Certified Floodplain Manager
By now, hopefully everybody knows that, the National Flood Insurance Program
(NFIP) standard for new residential structures is that the lowest floor must
be elevated "at or above the Base Flood Elevation (BFE)" - 44 Code
of Federal Regulations (CFR) Part 60. But what most people don't realize is,
that by adopting this minimum standard, one day there could legally be one
foot of water above the lowest floor elevation or the current BFE.
How can that be? Simple, it's a direct result of how floodways are defined
for NFIP purposes. After a detailed study has been performed on a stream reach
and the floodplain boundaries and BFE have been determined, a floodway can
be defined on that particular stream reach. A floodway is determined, by "squeezing"
the boundaries of the floodplain together (reducing the cross-sectional flow
area) until the calculated water surface elevations increase up to one (1)
foot (see Figure 1) while still passing the base flood event. This floodway
is referred to as a "1 foot surcharged floodway." There are other
factors that are considered when determining a floodway. One factor is that
the reduction in conveyance must be equal on both sides of the centerline
of the stream. Hydraulically speaking, this means one side of the creek is
not having more of a reduction in the conveyance of flows, than the other
side. Also, the "squeezing" shall not go beyond the current stream
banks and into the creek's channel, thus ensuring that the entire stream channel
will always be preserved as an "open area" to pass the base flood.
That is why it is so very important to regulate development in regulatory
floodways. The higher development standards that apply to regulatory floodways
ensure that any additional development in the regulatory floodway will not
cause water surface elevations to rise during the base flood.
So why define a floodway in the first place if it allows the water surface
elevations to increase by a foot? Because the positives results of defining
a floodway far outweigh any negatives. Let me explain. The main positive features
of having a floodway is that the floodway, when properly administered, reserves
an area to pass the base flood that will be free from future obstructions,
thus reducing future flood damages. It also allows for development in the
floodway fringe without requiring every single project that is proposed, no
matter how small, to perform a hydraulic analysis of the stream to determine
the impacts of the project on the current flooding conditions. Not having
a floodway designated would create a tracking nightmare for the local community
and would substantially increase the cost of new single-family structures.
The community would be responsible for tracking all development in the floodplain,
deciding when the floodplain was "fully developed," and prohibiting
any further development at that point in time. Developers or individual homeowners
would bear the cost of engineering studies to determine these floodplain impacts.
So what can your community do? To fully realize the benefits of having a
regulatory floodway defined, your community needs to adopt building standards
greater than the NFIP minimum standards to truly provide some additional measure
of protection, and I am not just talking about adopting a standard that requires
the lowest floor to be "one foot above the BFE." If your community
only adopts a "one foot above BFE" standard, then it is setting
up the situation where homeowners think they have one foot of freeboard above
the base flood, but if the floodway fringe is ever completely filled, then
their lowest floor could be the same elevation as the base flood someday.
People who have experienced flooding firsthand know that it doesn't take a
great depth of water in a home to do a lot of damage. For these reason I recommend
that communities adopt a standard requiring the lowest floor to be a minimum
of two (2) feet above the BFE in Special Flood Hazard Areas (SFHA).
There are several great reasons for adopting the “two (2) feet above
the BFE” standard in your community. First this standard takes into
account the future rise due to development in the floodway fringe. Therefore,
sometime in the future, when water surface elevations have legally raised
one foot, the structure should hopefully still have that one foot of protection
against the base flood. Another reason, even though detailed studies are based
on sound engineering principles and practices, is that there is still an art
in making floodplain and floodway analyses. Since floods don't read flood
maps, the “two feet above the BFE" standard takes into account
some of the uncertainty associated with floodplain calculations. This also
might help mitigate any unforeseen circumstance that might occur during a
flooding event such as floating flood debris blocking culverts, channels or
bridge openings. These obstructions could cause a temporary rise in the base
flood that the additional freeboard requirements could help mitigate since
the FIRM does not identify these areas of temporary obstructions. And finally,
by building the lowest “floor two feet above the BFE”, the structure
would be eligible for a lower insurance rate. This could add up to a substantial
savings on a homeowner's annual insurance premium over the life of the loan.
Hopefully this article has given you a better understanding, of what the
squiggly lines and floodway boundaries represent on your community's FIRM.
Even if you can't convince your governing body to adopt a higher standard,
hopefully you will be able to explain to the developer or homeowner as the
Floodplain Administrator, the advantages of elevating higher than your community
ordinance requires. If you would like to talk about these issues with me,
please feel free to contact me at 573.526.9119. Or if you like, comments can
be sent to me via e-mail, at firstname.lastname@example.org
back to top
Community Rating System
The NFIP has an incentive program called the Community Rating
System (CRS) that reduces flood insurance premiums for communities that perform
activities that exceed the minimum NFIP standards. The CRS has three goals:
reducing losses due to floods, helping communities achieve an accurate insurance
rating, and increasing the awareness of flood insurance.
For a community to be eligible, the community must be in full compliance with
the NFIP and be in the Regular phase of the program. Communities in the Emergency
phase of the program are not eligible.
CLASSIFICATIONS AND DISCOUNTS
All communities start out with a Class 10 rating (which provides no discount).
There are 10 CRS classes: Class 1 requires the most credit points and gives
the greatest premium reductions; Class 10 identifies a community that does not
apply for the CRS, or does not obtain a minimum number of credit points and
receives no discount. There are 18 activities recognized as measures for eliminating
exposure to floods. Credit points are assigned to each activity. The activities
are organized under four main categories: Public Information, Mapping and Regulation,
Flood Damage Reduction, and Flood Preparedness. Once a community applies to
the appropriate FEMA region for the CRS program and its implementation is verified,
FIA sets the CRS classification based upon the credit points. This classification
determines the premium discount for policyholders. Premium discounts ranging
from 5 percent to a maximum of 45 percent will be applied to every policy written
in a community as recognition of the floodplain management activities instituted.
The following table demonstrates how the CRS premium discount is reflected on
CRS PREMIUM DISCOUNTS
|CRS PREMIUM DISCOUNTS
HOW TO APPLY
Participation in the CRS is voluntary. If your community is in full compliance
with the rules and regulations of the NFIP, you may apply. There's no application
fee, and all CRS publications are free.
Your community's chief executive officer (that is, your mayor, city manager,
or other top official) must appoint a CRS coordinator to handle the application
work and serve as the liaison between the community and FEMA. The coordinator
should know the operations of all departments that deal with floodplain management
and public information. And the coordinator should be able to speak for your
community's chief executive officer.
The first step in the application process is to get a copy of the CRS Coordinator's
Manual, which describes the program and gives details on the eligible activities.
The manual includes application worksheets and the formulas for calculating
credit points. Computer software for completing the application is available
at no charge. In addition, the CRS has a Short Form Application that may be
more appropriate for your community. The Short Form is easier to complete than
the regular worksheets, but it does not cover some of the more complicated activities
you may be doing. Your designated CRS coordinator should fill out and submit
your application. The CRS will verify the information and arrange for flood
insurance premium discounts.
If you are interested in the CRS, and would like to visit with a community
already participating, you are encouraged to contact one of the communities.
For a current list of Oklahoma communities participating in CRS, please contact
the OWRB. Additional information is also readily available on FEMA's website.
FEMA provides a variety of tools to help make the application process go as
smoothly as possible.