things to consider before you build in a floodplain
By: Steve Darmofal
“I am building a new house, but it is located in a 100 year floodplain. The builder is supposed to start digging next week. Is there anything special I should do?”
It seems like I always get calls like this on a Friday afternoon.
If you want to build a new home in a floodplain area you need to make special plans to ensure that it will not suffer flood damage. It is just as important to make sure that it is properly removed from the floodplain. You do not want to be required to purchase flood insurance on it. The average flood insurance policy costs $700 per year. A mistake in handling this can easily cost you several thousand dollars during the time you will be in the home.
In the U.S. the law requires all federally backed banks and lenders to determine if a house they are lending money on is in a flood plain. If the house is in a flood plain then the bank is required to make the borrower have flood insurance.
There are ways to both limit the risk of flooding and not be required to pay the high cost of flood insurance. For new construction both the land and the home must be properly raised above the 100 year Base Flood Elevation (BFE).
This is a logical and common sense approach. If the property is higher than the 100 year Base Flood Elevation (BFE), then the new house should have a low risk of suffering flood damage. Prudent property owners and builders will make sure the area is raised higher than the BFE to minimize flooding risk. Most communities also require this.
As part of the loan process a lender will order a flood certification to determine if the property is in the floodplain. If the flood cert. comes back saying the property is in a floodplain you will be required to pay flood insurance. However banks will waive the requirement if they are provided documentation from FEMA that says the property is outside the 100 year flood plain. The area of the 100 year (or 1 percent annual chance) flood is called the Special Flood Hazard Area - SFHA for short.
FEMA is the Federal Emergency Management Agency. It manages the National Flood Insurance Program and publishes the floodplain maps. The National Flood Insurance Program is also the underwriter for all the basic flood insurance policies and pays all the claims.
If you don’t want to pay flood insurance you must also get the property removed from the flood plain. And you must do this before you build. Doing things in the proper order is very important.
Most homeowners will need to hire a land surveyor or civil engineer to work through the removal process with FEMA.
The first thing is to have the building site surveyed to determine if the existing ground is above or below the BFE. The Flood Insurance Rate Maps are normally pretty accurate but occasionally they contain mistakes. An area that is naturally high can be incorrectly shown in the SFHA.
If the natural ground is above the BFE and no Fill was placed to raise it above that level, then you need to obtain a Letter of Map Amendment (LOMA). If Fill had been placed or needs to be placed, then you need to get a Letter of Map Revision based on Fill (LOMR-F).
Getting a LOMA when no fill is required. If the survey shows that the building site is naturally above the BFE then you should go through the LOMA process to get the portion of the site where the building will be constructed removed from the SFHA. FEMA does not charge a fee to process LOMAs and they have up to 60 days after receiving a request to make a determination.
Getting a LOMR-F when fill is placed. If the survey shows the area where the house will be built is currently below the BFE then fill will be needed to raise the site. This will require you to go through the LOMR-F process. A LOMR-F is also required whenever fill has already been placed to raise the site above the BFE. The LOMR-F needs to be obtained for the area of the house before you start digging the foundation.
When fill is needed you need to first check with your local floodplain administrator to determine if a floodplain fill permit is required. Most communities require you to obtain a permit before you can place any fill in a floodplain area. This normally involves completing an application and preparing a sketch showing where you plan to place fill and how much. Some communities also require a compensating volume of cut somewhere else on site to offset any fill placed in the floodplain. Other communities may not even allow fill or construction in a floodplain area.
After you obtain the fill permit you can place the dirt. Then you call the surveyor back to take measurements of the completed fill. He will prepare drawings showing as-built conditions and certify the elevations so they can be submitted to FEMA. FEMA also requires that the local floodplain administrator sign a Community Acknowledgment Form. This basically says that fill was placed properly and the property is reasonably safe from flooding. If you don’t get the floodplain fill permit before filling the property you could run into trouble with the local authorities at this point. In addition, FEMA charges a processing fee for a LOMR-F. The normal charge is $525.00 for a single lot request.
Did you notice that FEMA has between 60 and 90 days to respond, depending on the request? FEMA does not offer a special “rush” service for processing these. Don’t expect a quick turnaround. Based on my experience they generally take 6 to 8 weeks to get a final determination. Lack of planning on your part is not an emergency of FEMA’s part. They process cases in the order they are received. It does no good to call FEMA to ask them to speed up the review of your case.
I realize that often builders and property owners get into a big rush to start work on a house. There are deadlines to meet and many don’t want to take the time needed to properly go through the LOMR-F process with FEMA. This is a mistake. Builders and owners need to plan their projects ahead of time and take into consideration FEMA approvals.
The thing to understand here is that things must be done in the proper order. If you build a house first before requesting the property to be removed from the 100 year floodplain then you could get the request denied. Removing a structure is different than removing a piece of undeveloped land. If the ground where your house will be built is below the BFE and shows up as being in the SFHA then your house will be in the floodplain. And if you plan to have a basement or crawlspace lower than the BFE, then you definitely need to first get the land removed from the floodplain.
“Why do I need to get the land removed first? Why can’t I just build now and submit the request later?”
For a structure on fill to qualify for a LOMR-F both the lowest adjacent ground grade and lowest floor need to be at or above the BFE. The bottom of your basement or crawlspace is considered to be the lowest floor. If you build a house with a basement or crawl on fill in the floodplain area, and if the lowest floor is not at or above the BFE, then FEMA will not issue a LOMR-F after it is built. FEMA is not flexible or open to common sense in this. Timing is critical. What the map looks like, when you place fill, and when you submit the request will determine whether you will have to pay flood insurance or not. It is important to have a professional guide you through this process.
But if you get the land removed by FEMA before you begin construction, then you will be building on land that is no longer in the floodplain. Then the home will not be subject to mandatory flood insurance from your lender. You will still need to have the lowest adjacent grade higher than the BFE. Most communities require new construction to be at least 1 foot higher than the BFE.
For these removals either the entire lot or a portion of the lot can be removed. No ground in the area to be removed can be lower than the BFE. FEMA will require a topographic survey showing the elevations. Your surveyor will prepare a metes-and-bounds legal description of the area above the BFE area where you want to build to get it removed from the SFHA.
Here are a few other considerations when building in a flood plain:
Access to the property during a flood. If you want to construct a building on a site below the BFE, then you may need to do more than just fill the buildable portion of the lot to at or above the BFE. Most local communities are going to require that you also provide drive access to the structure from the street above the BFE.
We worked on a local project where the building site was located in a floodplain a couple of hundred feet away from the main road. The main road was much higher than the 100 year flood. The river was located a couple hundred feet beyond the house. The property owner got the flood plain fill permit, raised the building areas well above the BFE, and then built the home. A couple of years later, the stream experienced a severe flood and the waters rose to a level where they surrounded the house. The area around the house became an island because water flooded the driveway and all the surrounding area. When the property owner tried to drive his pick-up truck across the driveway the flood water was so deep that the pick-up truck flooded and began to float away. The local community is now requiring that homes in this situation have access to the main road that is entirely above the 100 year floodplain. The property owner (and his neighbors who were in the same situation) needed to go back and get another floodplain fill permit to raise the driveway and add a culvert large enough to let the flood water pass.
No leach fields in floodplain. If you are planning to build a new home in on site that is in the SFHA and there no public sewers available, then you need to consider the placement of a septic tank and leach field. Many local health departments will not allow the placement of septic tanks and leach fields in 100 year floodplain. Check with your local health department if this is the situation. You will need to have a minimum sized area above the BFE. If there isn’t a large enough area outside the floodplain, you may need to bring in fill to raise part of the property above the BFE.
One of my clients who was building a new home did not have enough area above the BFE to place a leach field and could not get health department approval of the site. Fill needed to be brought in to fill above the floodplain to get enough area to construct the leach field.
Some communities may require special permits for remodeling, improving, or expanding a building if it is located in a floodplain. FEMA regulations also normally do not allow fill or structures to be placed in a Floodway area. These are both special cases, and there is not enough space to cover them here.
A final story with a not so happy ending.
The chief building official in a local community here once told me that in one of the townships a property owner had submitted a LOMR-F request to remove a property from the SFHA. They were planning to build a house. As soon as the lot was filled and the request was sent to FEMA, they began construction and dug out a big hole and poured the foundation. This was done before FEMA had issued the final LOMR-F. The chief building official told me that FEMA had someone perform a field-check for this particular request. They found that the site had a big hole for the foundation. The site did not appear how it was presented on the application and the bottom of the excavation was obviously below the BFE. FEMA denied the request for the LOMR-F. The property owner was not able to get the insurance requirements waived for the property. After that, the community changed policies. It no longer issues building permits until after LOMAs or LOMR-Fs are obtained from FEMA.
Conclusions:
When your property is located in a floodplain, please plan enough time for the removal process. Don’t start building your home before the LOMA or LOMR-F is issued. A knowledgeable professional will be able to guide you through the process. When looking for someone to help you in this situation ask how much experience he or she has in obtaining LOMR-Fs. Ask if they have done work for others in your area and what the results have been. Experienced professionals will often have good working knowledge of the situation in your particular area and should be able to answer your questions.
Steven Darmofal, P.E. is a professional engineer in Ohio with the consulting firm TD Engineering, LLC. He is an expert on floodplain issues and has taught numerous continuing education courses for real estate agents in Ohio. He has worked on projects successfully removing over 600 properties from the 100 year floodplain. Over the years these clients have collectively saved over $1,000,000 in flood insurance premiums.
