Special Flood Hazard Area • Zone AO

Removal Qualification

Removing a structure from a Zone AO Special Flood Hazard Area can be tricky with different rules for different situations.

Most of the time, the Flood Insurance Rate Map indicates a condition of shallow street flooding to a specified depth. In such a case, it has to be demonstrated that if the street actually flooded to the depth given, the surface elevation of water could not make contact with any part of an insurable structure. (An insurable structure is any that is used as collateral for the federally insured loan. This would not include a garden shed, for instance.)

Therefore, the ground surrounding the home must rise up from the street frontage to where the lowest grade adjacent to the structure is higher than the crown of the street or highest top of curb (whichever is higher) by at least the depth of flooding.

In other words, if a datum is assumed to be zero at the crown of the street or the highest top of curb, the lowest adjacent grade (LAG) to the structure must be equal to or greater than the depth of flooding specified (as shown in the figure below). If this is established by a certified survey, the structure can be removed from the Special Flood Hazard Area by requesting a Letter of Map Amendment.

There is somewhat of an inherent problem with FEMA's methodology described above. When a street is new, its high point (crown) is likely to be at the same or very similar elevation as the highest top of curb. However, over time the crown will increase as a typical road maintenance practice is to overlay a street with a layer of asphalt, thereby raising the pavement surface by at least an inch and a half. One or two overlays will change conditions enough that a home that would qualify for removal from the SFHA one year might not qualify the next.

Another issue is that properties located at the corner of two intersecting roads are less likely to qualify for removal from the SFHA. This is because the grade of the lot is often congruent to the slope of one of the streets, thereby causing the lowest adjacent grade to the structure to be below the highest top of curb.

Example of a Service Request and Applicable Fees

A property owner in San Lorenzo requests that Alaco determine if his property can be removed from a Zone AO Special Flood Hazard Area.

Occasionally, a negative determination can be determined with information on hand and no need for a site visit. If possible, Alaco will do so as part of a free consultation over the phone or by email. If not possible, a site visit will be necessary, thereby incurring a charge of $150.

Based on basic, unmeasured observations made at a Zone AO site, a negative determination might be determined where it would not make sense to proceed with a survey at additional expense. In such an event, Alaco's work would be done, and $150 is all that would be owed. However this is typically rare, and it usually makes sense to perform a survey. This is because a definitive determination cannot be made any other way if conditions for removal appear close by observation. The fee for performing the needed measurements is $150.

If measurements result in a negative determination and there is no requirement for insurance (because there is no federally insured mortgage) the work is complete and the total fee is $300.

If measurements result in a negative determination and there is an insurance requirement, it may make sense (for the purpose of possibly lowering the NFIP insurance rate) to have Alaco prepare and certify an Elevation Certificate for $400. The total fee would therefore be $700.

If measurements result in an affirmative determination, then it would make sense to forgo the preparation of an Elevation Certificate and proceed with a LOMA request instead for $400. Alaco will complete the application process via the online eLOMA portal, coordinating with and providing information and materials to FEMA as required. The eLOMA tool is only available to certain qualified professionals, and its use normally expedites the process significantly. The total fee then in this case would be $700.

Request a Flood Hazard Survey

E-mail Lawrence Johmann at larry@alaco.us or call/text at: 510-200-8414 Provide the address of the property requiring a survey.