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Ordinance Update
City of Rexburg
City Council Work Meeting
11/17/2021
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What is the “floodplain”?
Special Flood Hazard Area (SFHA)
100 year floodplain
Zone AE on the map
Area that has a 1% chance of flooding each year.
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What is the “floodway”?
A floodway is the channel of the river and the adjacent areas that must be reserved in an open manner so that the cumulative increase in water surface elevation is no more than 1 foot.
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Why does the City participate in the National Flood Insurance Program (NFIP)?
Participation by the Community allows property owners to purchase flood insurance through the federal government.
Flood insurance is usually required by lenders for buildings within the floodplain.
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Rexburg’s History with the National Flood Insurance Program (NFIP):
The NFIP was created in 1968.
Rexburg joined the NFIP emergency program on June 18, 1975. (This is a community’s initial phase in the program before flood data is available.)
The City joined the regular NFIP on June 3, 1991 after the maps were finalized.
The original ordinance (717) was passed on April 17, 1991.
An update to the ordinance (1129) was passed on April 15, 2015.
The State Floodplain Coordinator reviewed the City’s current ordinance and is requiring that the ordinance be updated again before the end of 2021.
After the new maps are completed, the City will need to update the ordinance again.
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What does FEMA require of the City in return?
Community is required to adopt and enforce a floodplain management ordinance that meets minimum NFIP requirements.
Ordinance requires floodplain development permits for all development within the floodplain.
Generally requires that the floor of a structure be elevated to or above the “base flood elevation”.
Ordinance regulates the development within the floodplain and floodway, to minimize the risk of flooding to the overall community.
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What if the City decides we no longer want to enforce the ordinance?
Compliance is checked through CAV’s (Community Assistant Visits) by FEMA or the State Floodplain Coordinator every few years.
Communities that do not enforce the ordinances can be placed on probation or suspended from the program.
Probation causes premiums to increase, but still allows purchase of insurance.
Suspension means that insurance policies can’t be purchased or renewed.
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What if the City decided that we no longer want to participate in the NFIP?
Flood insurance through the NFIP would no longer be available within the community.
Existing insurance policies could not be renewed and lenders would have the option to demand repayment of existing loans.
Federal agencies would not approve any form of financial assistance for acquisition or construction purposes in the SFHA. For example, this would prohibit loans guaranteed by the Department
of Veterans Affairs, insured by the Federal Housing Administration, or secured by the Rural Housing Services.
If a Presidentially declared disaster occurs as a result of flooding in a non-participating community, no Federal financial assistance can be provided for the permanent repair or reconstruction
of insurable buildings in SFHAs. (Eligible applicants may receive those forms of disaster assistance that are not related to permanent repair and reconstruction of buildings.)
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Flood Insurance Study
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Flood Insurance Study
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Current Flood Insurance Rate Map (FIRM)
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Army Corps of Engineers Map
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Initial FEMA Map
SUGAR CITY
REXBURG
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Initial FEMA Map with <0.5 ft water removed
SUGAR CITY
REXBURG
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Map Showing Flow Direction and Depth
TETON
REXBURG
SUGAR CITY
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Current Status of Map Update
Still waiting for FEMA to finalize and release the revised maps.
FEMA is waiting for the mapping of the Henry’s Fork and South Fork of the Snake River to be completed and will release all maps at once.
May still be a couple of years out before the new maps are released.
There will be a review and comment period before the maps are official.
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Changes to Floodplain Ordinance
Based on the State approved ordinance.
Adds approximately 56 definitions.
Rewords/clarifies most other sections to better match FEMA instructions.
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Clarifies who will act as the City’s Floodplain Manager
“The Mayor will appoint a staff member to act as the Floodplain Administrator, to administer and implement the provisions of this ordinance. If a Floodplain Administrator has not been
appointed by the Mayor or if the appointed person is no longer able to perform these duties, the ordinance will be administered and implemented by the City Building Official, until
a new Floodplain Administrator is appointed.”
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Freeboard (minimum distance of floor above base flood elevation)
Freeboard
The 1991 ordinance required 0 ft of freeboard.
The 2015 ordinance requires 1 ft of freeboard (currently being enforced).
The State recommends 2 ft of free board.
The draft ordinance currently requires just 1 ft of freeboard.
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Elevation Certificates
The State recommends that 3 elevation certificates be required.
1 based on the construction drawings.
1 after the lowest floor is constructed.
1 after construction is complete. (required)
The draft ordinance recommends the first 2 and requires the final elevation certificate.
There is a fee paid to a surveyor for each certificate. ($1,000-$1,300)
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Penalties for Violation
State recommends: “$100 fine or imprisoned for not more than 180 days, or both. Each day the violation continues shall be considered a separate offense.”
Current ordinance: one-time fine of $300 or imprisoned for not more than 180 days, or both.
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Development before the New Maps are Finalized
State Ordinance has the following paragraph:
“Until a regulatory floodway is designated, no encroachments, including fill, new construction, substantial improvements, or other development shall be permitted unless certification
with supporting technical data by a registered professional engineer is provided demonstrating that the cumulative effect of the proposed development, when combined with all other existing
and anticipated development, will not increase the water surface elevation of the base flood more than one foot at any point within the community.”
This would require hydraulic modeling by an engineer for development anywhere in the floodplain.
Estimated cost for a single family home: $6,000 to $8,000
Estimated cost for larger developments: $30,000 to $80,000, depending on size and location.
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Next Steps
Incorporate any comments from City Council or staff into draft ordinance.
Send draft ordinance to State Floodplain Coordinator for review and approval.
Bring the final ordinance before the Council on December 1st or December 15th.
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