Demystifying the NFIP: An Introduction to Floodplains

Steve Casey and Matt Gramza, two of CEC’s water resource experts, discuss FEMA’s National Flood Insurance Program (NFIP), some of the technical aspects of flood insurance studies, and the implications of local floodplain requirements. Listen to hear how floodplains are calculated and how they affect you.

For more information, you can visit: https://www.fema.gov/flood-insurance, https://www.fema.gov/press-release/20210401/fema-updates-its-flood-insurance-rating-methodology-deliver-more-equitable and National Flood Insurance Program Now Factors in Climate Change – Videos from The Weather Channel | weather.com

Podcast Transcript

Announcer: Welcome to CEC Explains your deep dive into fascinating subjects from the worlds of engineering in the environment, brought to you by Civil and Environmental Consultants. And now from our CEC studios around the nation this is CEC Explains.

Steve: Welcome to CEC explains. My name is Steve Casey, I’m a civil engineer here in our Nashville office and the Water Resources lead for the company. And we are here today to talk to you about the topic of the National Flood Insurance Program (NFIP) that is part of the Federal Emergency Management agency. And I’m joined by my colleague Matt Gramza up in our Cincinnati office.

Matt: Thanks Steve, thanks for inviting me and I’m excited to be here today, so as Steve said, my name is Matt Gramza. I’m the Water Resources Practice Lead in the Cincinnati office and I’ve loved all things water, all my life. It just kind of steered me towards Water Resources. I grew up in the Great Lakes and still just love everything about water, so I am a professional engineer and a certified floodplain manager and a certified professional in erosion and sediment control, so I’m just happy to talk with you today Steve about the NFIP.

Steve: Great, thank you Matt. And like Matt, I have enjoyed just being around water and you know stormwater in particular and have really enjoyed being able to do a variety of projects with Matt over the years. Fact, we worked on a historic project several years ago after the 2010 Middle Tennessee flood. So we’ve got a lot of experience in this topic and hope that we can introduce the topic to you and kind of talk through some of the technical aspects of what goes into establishing these floodplain boundaries that you see on maps, as well as the implications for a homeowner, as well as someone who’s wanting to develop property.

So with that, I want to kind of talk a little bit about this past Saturday, August 21st 2021. We had some very tragic flooding that occurred just west of Nashville, in which an enormous amount of rain fell over a short period of time and it caused just incredible property damage, people died. It was very tragic and it just really calls to attention this is a topic that is really applicable to everyone. Everyone lives in a flood plain. If you think about it just depends on how large the storm event is. And we’re going to talk about the specifics of the National Flood Insurance Program today, but I did want to mention that, this is a topic that we have helped clients navigate, but it’s also one that even as an individual homeowner that it’s very helpful to just be aware of flooding. And I wanted to let Matt talk a little bit more about just the safety aspect of the topic that were discussing today.

Matt: Sure, Steve. You know, safety at CEC is is integral into everything we do. And you know kind of a safety topic that’s near and dear to my heart, as a certified floodplain manager, you know plays into the the type of catastrophic, you know, flash flooding that that happened there in Tennessee and other areas of the country this weekend.

Steve and I work pretty closely with emergency management agencies, when we’re developing flood, studies and inundation studies. And one of the stories that a state director for an EMA had told really drives the point home of the you know safety campaign Turn Around Don’t Drown. He told a story of a recent flash flood, a local homeowner just wanted to get back to his home to, you know, potentially survey the damage and drove into, what he thought was shallow water, and it ended up being deep water because the bridge was washed away. And ended up falling into the stream and drowning. So it’s just, you know, critically important to understand. You never drive your vehicle into any kind of water. You just, you just never know.

Steve: Yeah. Thank you, Matt. So to jump into our topic today, we’re going to cover several different terms that may be unfamiliar to you. And we’re going to try and just define those as we come across them. But I’m going to lead off with the two kind of primary terms FEMA and the NFIP. FEMA stands for the Federal Emergency Management Agency. And NFIP is the National Flood Insurance Program.

Matt: The National Flood Insurance Program is a national program, but really at the heart of it is the communities that are involved in delivering the program to the public. It’s really those local communities that drive the program that emphasizes public safety. That help homeowners and developers, you know build safely and effectively in flood plains or near flood plains. So it’s that local component that sometimes gets lost on the you know the overall aspect of the program, that’s really important. So, you know, the National Flood Insurance Program is managed by FEMA is delivered to the public by a network of approximately 60 insurance companies in the NFIP direct.

It is, you know, as I mentioned, rolled out at the local level and the local communities that are involved, which is over 23,000 participating NFI communities. And it’s those communities that are responsible for delivering and, you know, kind of governing the NFIP. And the reason that I think that’s important is those local communities know better than anyone. What they’re flooding issues are, where their vulnerabilities are, where they’ve had the most damage due to flooding and so they can really infuse more local regulations where they may need to be implemented. And really you know, drive that efficiency and effectiveness of that program home.

Steve: Yeah. Thank you. And it’s interesting statistic that I found from FEMA about just one inch of flood water can cause up to 25,000 dollars in damage. So this, you know, it you get water in a home or a business and there’s significant implications for that. So, let’s just spend a couple of minutes here, kind of defining this hundred year or 1% annual chance concept that the NFIP uses as a kind of establishing a level of risk for floodplain.

Matt: Yeah. So the term “100-year flood,” is often misconstrued, you know, commonly people interpret the 100-year flood definition to mean that, you know, this this level flood can only happen once every hundred years. And this is incorrect. You could experience a 100-year flood twice in the same year, two years in a row, or four times over the course of a hundred years. It’s really a statistical term that FEMA is, you know, going away from using the term “100-year” for that reason. The true risk of the 100-year flood is better defined as the 1% annual chance. So it, you know, essentially comes out to you know, the inverse of the 100-year storm, which is the 1% annual chance and that’s the true statistical risk for the storm. But again, you know, we are seeing more and more 1% annual chance storms, you know based on local conditions changing and global conditions changing with climate change and with other other aspects of how we’ve grown and and you know developed ourselves over over the region.

Steve: Mm-hmm, yeah that’s a good point. You know, you mentioned climate change, but also just as development continues that 1% annual chance event. I know down where I’m located down in middle Tennessee. That’s about 8 inches of rain over a day and you know that that obviously creates a lot of runoff that goes into the rivers. And were talking about floodplains, we’re talking about the analysis the hydrologic and hydraulic analysis that goes into figuring out how deep will the water get in those rivers and streams during that 1% annual chance event. And that just to mention that historic event that happened on Saturday. Just a couple of days ago, you know much more than a 1% annual chance event happened there. Where you had 14 inches in some places falling in six hours in some cases.

So just an enormous amount of runoff from that. So, obviously FEMA had to choose some level of risk in order to establish, okay this will be the floodplain that we regulate. So, what about as a homeowner? I guess, maybe, how likely would it be that you might flood? If you were located in a 100-year floodplain or 1% annual chance flood plain.

Matt: That’s a good question, Steve. You know, one thing that’s that’s also missed on flooding in general, is flooding is the most expensive natural disaster that there is. More expensive than any of the others because flooding can literally happen anywhere. You know, people think you know, flooding is only a high risk or potential in you know, areas like we live in that have a significant amount of flooding sources, and rivers, and streams. But the reality is flooding can happen literally anywhere, including out at our Phoenix, Arizona office. You know, there’s there’s flash flooding out there, commonly known as washes that definitely impact homeowners, but you know it’s really a good way to look at, you know, what are the risks? What are the odds of being flooded?

And, you know, a couple interesting statistics from NFIP are that you could look at a flood risk from a typical homeowner is saying, you know, what are the chances? What are the odds of a 1% annual flood will happen during the lifetime of a 30-year mortgage? And the statistics show that you have a 26% chance for a structure located in a special flood hazard area to see a 1% annual chance flood, which is interesting because, you know, converse to that, the odds are only one to two % that your house will catch fire in that same 30-year mortgage period.

Steve: Hmm wow.

Matt: So you can see a significant increase in risk from flooding.

Steve: Mm-Hmm. That’s really interesting. I didn’t realize it was such a disparity between those two disasters. And I think something else to mention about this, I know I’ve experienced this in some of the communities that I’ve done work within, flood maps change. You know, as new data is collected on rainfall events, that affects how much rainfall falls in a day and and how a 1% annual chance event is determined. Couple that with development and changes within the floodplain. And I know, homes that were originally built outside the floodplain, even near where I live, are now located in the floodplain because the maps were updated.

So just because you, you know, purchase a house outside the flood plain doesn’t mean that it will remain outside the flood plain. Unfortunately, and so Matt, if you could, maybe give us a little bit of the background of, you know, when the NFIP began and just maybe some of the more recent developments that have affected the insurance program.

Matt: Sure. So, Congress established the NFIP on August 1st, 1968 with the passage of the National Flood Insurance Act of 1968, which has been modified over the years. In 2018 FEMA, engage the broader policy community, including academia and other government agencies, and developed an affordability framework in response to congressional mandate under the Biggert-Waters Flood Insurance Reform Act of 2012. Congress sought to build a more sound financial framework for the NFIP by directing FEMA to remove the discounts for some policy holders with homes insured by the NFIP. So, that policy holders would be given flood insurance rates that are more accurately reflected their expected flood losses. At the time, Congress recognized that removing discounts might cause flood insurance to become unaffordable for some households and mandated in areas that flood study insurance affordability we’re, you know, enacted to address the concerns.

And you know, rising premiums are definitely, you know, that concern constituents and multiple communities have raised this issue. You know, prompting Congress to later pass the Homeowner Flood Insurance Affordability Act of 2014, which roll back some of the changes implemented and recognized additional affordability challenges associated with increased premiums. The policy mandated FEMA develop an affordability framework aimed at providing targeted assistance for policyholders in addition to dealing with affordability requirements.

So, you know, I think the other thing that, you know, that’s certainly happened is that FEMA is looking much more to a risk-based rating system for developing those premiums. You know, not everyone is looked at as just how high their house is built or their business is built above the floodplain. It’s much more based on risk, and that could be a number of factors that could be proximity to dams, proximity to levees, you know historical flood-proneness of your local flooding source. All these things, you know are going into revising and changing the program.

Steve: So Matt, I think, you know, just with the advent of this better modeling capability more data that we’re, you know, it’s been collected over the years with regard to rainfall amounts and the analysis of all of that. FEMA is definitely, it seems, trying to dial in this risk and hopefully make it a more equitable type insurance program. But as I understand it, there are still some grandfathered rates and so forth. I’m not sure of the whole timeline of that. But suffice it to say that you may see some changes in rates as a homeowner who lives in a floodplain. So, do you want to maybe introduce what goes into? These flood insurance studies a little bit?

Matt: Sure, Steve. So, you know, flood insurance studies basically are/have been developed over time to be kind of the backbone of the National Flood Insurance Program. And you know, kind of backing up. They are just a variety of level of detail. You know, some of the oldest studies that we work with are extremely coarse based or very old. You know, maps that were not necessarily developed for flood insurance studies, but we’re best available data.

So depending on where we are in the country, we run into where we have to perform flood insurance studies, and a part of that is understanding, you know, the history of the current flood zone and how it was developed, how it was calculated. Is it approximated? Is it detailed? And understanding that we develop basically a program for flood insurance study of what we believe we need from a technical standpoint to improve the delineation of the floodplain typically for 1% annual chance flood.

And as I mentioned we could start with very old and very coarse approximated data or we could start with maps that have just been updated last year. With you know, very high level detail that you mentioned based off better terrain data, whether that’s project-specific lidar that was created just for that particular flood insurance study. Which is very detailed data that we work with many times. The map zones are highly detailed with very high resolution imagery as your background, so that you can really truly see what the affected inundation zone may what type of structure it may affect. And so, there’s just a, you know, a whole range of available published flood insurance rate maps out there. And we, you know, as I mentioned we get involved with all different levels of how those maps were created. And a lot of times, the local communities rely on engineers and consultants like Steve and I to help them improve their flood zone maps. And that may not be, you know, sometimes it’s not a direct project that the community is working on. But if we’re working on a particular development in the flood zone and we’re required to prepare a flood insurance study to make sure that that development is safe and is properly developed. You know, under the National Flood Insurance Program regulations. The communities can use that updated study that detailed study, that new map delineation and flood zone delineation to improve, you know, what they’re available data and information is for their community. So there are many times that, you know, kind of through the work that we’re doing. We’re helping improve the accuracy and quality of those of those maps.

Steve: Mm-hmm. That’s a great point. And just to piggyback on that. We’ve had several instances where we’ve been working on developments and the flood insurance study. It may have just been published in the last year or so, yet some of the data that it’s based upon maybe five, six, seven years old. Just because of the time it takes to make it through that approval process within FEMA. And so, we also sometimes find ourselves improving studies that aren’t that old. Just to illustrate some of what you just brought up Matt. About the varying levels of precision with these studies.

I know in my own past, when I first started in this industry, I remember doing flood studies in which a USGS topographic map was my base information. And sometimes it might have had a 10-foot or 20-foot contour interval. Meaning that every contour on that topographic map represented. You know, a 10-foot difference to the contour next to it. You know, nowadays we’re working with contour information that may only have one or two feet difference in each contour line. Which is as you can tell much more precise, but I remember using that paper, paper maps, and physically drawing cross-sections. And putting that manually into the Corps of Engineers HEC-RAS model. HEC-RAS model and developing what’s called a geometry file. And, you know, basically telling the model here is the rivers channel cross section and the flood plain.

And then, developing the flow file based upon sometimes regression equations based upon actual stream gauging stations. And coming up with a flow rate that would be input into the model. And then really that’s that’s what it is. You’re taking the geometry and then you’re taking a flow and your routing that flow through the stream reach. And so it can be as coarse as taking a USGS topo map and manually doing it with paper, or it can be in some cases now there we’ve got two dimensional modeling where we take the entire surface instead of just using cross sections. So there’s a, there’s a spectrum there. I guess is literally what I wanted to explain and depending on, when the last time a map was updated or a flood insurance study was updated will dictate often where that flood study lies on that spectrum. You know how precise it is.

I do want to say this one thing about the flow, going back to that geometry and flow. You know, those are the two things really that go into building this this model. The flow is influenced, not only by climate change, but also development as development continues and more impervious area is added to a watershed that increases the flow rate. And so that’s another variable that can increase the level of flooding, over time. And so, I guess with regard to that this whole concept of flood insurance studies and flood insurance rate maps. Matt, let’s talk a little bit about this, the different zones that are on a flood insurance rate map. And let’s also talk about this floodplain and floodway, you know the difference between those two.

Matt: Sure, and you make a good point when you talk about the variabilityness of the flow file and all that influences it. The flow file is basically created from the hydrology, you know, so we’re trying to estimate. Basically, you know how much runoff from a storm event is going to make its way from the landform down into the receiving stream or the flooding source.

Steve: Mm-hmm

Matt: And, you know, there’s a lot of nuances. There’s a lot of you know datasets and technology and different things that go in and go into, you know, coming up with good hydrology. And in the past, I think the the NFIP has when they when they’ve gone to update maps they’ve been a little bit more focused on better terrain data as you mention, which is important.

Steve: Mm-hmm

But I think what is equally important is better hydrology.

Steve: Mm-hmm

Matt: You know a lot of the the original stream flows, you know, peak stream flows we’re calculated, you know, on a very regional or sometimes even almost national standpoint. It’s really important to to really, you know, get into the local watershed and the local historical rainfall data. You know, precipitation information that that helps develop, you know, a more realistic or, you know, more appropriate storm event for your particular watershed.

So I think the combination of those two, you know, better hydrology, better, you know, geometry goes into making, you know, a better flood insurance study in a better flood model. With that being said, even though there’s more technology and your level precision can come can go up. You know, you still have to use professional and engineering judgment to understand that there is still so many variables in the systems. And you really want to look at what the potential flood depth is based on a range of. You know, potential, what if scenarios and you need to be conservative when you’re thinking about those things.

Because, you know, there are a lot of variables like we’re talking about and if you experience and understand you really talk more about ranges of flood depths instead of just an exact flood depth, that’s important. The other thing that’s important, is when you’re going to do a flood insurance study, really understanding what the purpose is. And Steve you and I talked about this in our, you know, monthly Water Resource practice calls. You know, throughout the company, making sure when you’re going into a new flood study, you understand what the actual purpose is because that can drive how you develop the actual flood model and how much or how little detail needs to go into it. You know, from a simple flood study where we’re trying to determine if there’s going to be a potential impact on the 1% annual storm based on a development of a structure. Or, you know, something else in the floodplain all the way up to a put a very detailed dam breach analysis or levee breach where the the level of precision in the Inundation Study, just ramps way up. And there’s a lot more that go into the what-if scenarios, the sensitivity analysis, to make sure that we’re getting good data and not just data, you know, we really need to to run it through the quality process. To make sure we get, we get good data and useful data. So we can make good decisions, help our clients and help the communities make good decisions about, you know, development in or around floodplains.

Steve: Mm-Hmm. Yeah, totally agree. And I think that, you know, you have to take into account how the flood insurance study was developed. If you’re working on a development that you’re wanting to change things. And you know, we haven’t even talked about these. How you revise a map yet. But that’s something else to take into account, is, you know, what went into that flood insurance study and so you can’t really look at it as a blank slate.

You need to go in and figure out kind of your building on the shoulders of those that went before you on developing what’s really going to happen in that area during the flood. And I often get this question about and I hear sometimes people interchangeably using the terms floodway and floodplain, and I wanted to just talk a minute about the different types of zones that we see on these maps.

You hear about different like Zone A or zone AE. Zone AE with floodway established. Zone X, you know, there’s different things that you see on these flood insurance rate maps. And I’m just going to try my best here and Matt, I’ll let you fill in, but I’m going to explain how this difference between floodplain and floodway. And I the best way that I’ve been able to explain this to clients and just members of the public is, imagine that you’ve got the floodplain and then you just take two boundaries on each side of your floodplain. And you just start squeezing that floodplain in and the point at which you squeeze that flood plain in you’ve basically made the elevation of the water, go up. No more than one foot. That’s where your floodway line is. It’s not this line that you can go out in the field and locate. It’s a modeling exercise, and it’s really intended for if participant, NFIP participating community wanted to allow development within the floodplain in such a way that they didn’t require compensation of the fill in the floodplain, but they relegated that fill to outside of the floodway. They could be somewhat certain that the the 1% Annual Chance Flood events, not going to go up more than a foot.

And so it’s really this management tool is probably a good way to explain it. But not every flood insurance rate map has that. Sometimes we’re just left with an estimated flood plain, which is like the Zone A, the Zone AE, being more of a detailed study where you’ve actually got cross-sections. And you know, you’ve established an elevation.

Matt: And the importance of the floodway is you know, that that’s on. That’s left you know, closest to the flooding source is critical to keep structures and development, especially homes out of because it is the most dangerous part of the entire floodplain. It is the area that’s typically left undeveloped so that the flooding source can pass. Not only, you know, high velocity water during a flooding event, but many times more importantly, more dangerously flood debris, that gets caught up in the flood waters that, you know, can cause a significant amount of damage. So, you know, floodway is a sensitive zone. That you know, there’s a much higher level of regulation inside the floodway. Then there is outside of the floodway, but still inside of the floodplain. And that, that delineation is really important to understand.

So you’re right. You could you could be working in a one thing. I’ll back up. And just say, as we’re typically talking about riverine type flooding. There’s also coastal flooding that I’d have a whole series of different flood zones, but Steve and I are kind of talking more about riverine flooding. And, you know, he’s right there. The Zone A, typically is an approximated flood zone and then that, you know, Zone A many times when you’re we’re helping a client develop a new project that has a impact from a Zone A, we’re required to do a detailed study. To help better define that flood zone and understand what the potential impacts are for the proposed development. So, you know, that many times we’re taking approximated flood studies, and actually, creating detailed flood studies, so that we can we can properly evaluate. So you’re right. You know, there’s the Zone A approximated AE is typically a detailed flood zone which has many times, has both the floodplain and the floodway already delineated and includes what’s called the Base Flood Elevation also known as the BFE. So that is typically the 1% Annual Chance Flood Elevation. That’s known as the Base Flood Elevation. That’s an important definition in the NFIP. And a lot of the regulation around is developed from that. Base Flood Elevation in what’s called freeboard. So many times you’re allowed to start building your building at the BFE plus the freeboard and that freeboard is one of the is really one of those areas. I talked about how the NFIP gets, you know, kind of push down to the local level to be implemented. And that local level has the ability to increase the requirements and the regulations for development and floodplain and many times they increase that required freeboard. So the, you know, FEMA sets the baseline of that, freeboard at one foot above the base flood elevation to where you can start building, but many communities increase that to one and a half foot two foot. I’ve seen them as high as three foot and that’s significant.

You know, if you’re having to fill a site to develop, you know, to have it developed safely within a floodplain. So that that’s an important aspect to make sure, you know, our clients and we help them have a handle on. The other thing that’s important in, you know, I know Steve this is near and dear to his heart to because he as a, you know, he helps a lot of communities with floodplain management and act as their, you know, floodplain administrator floodplain coordinator.

We recommend, you know, contacting those local floodplain coordinators, local floodplain administrators early on in your projects, so that you really understand what the true regulations are for that local community. You can get a understanding if they’re currently in the middle of a flood insurance study to update their mapping. A lot of information is important and really many times the local flood plain coordinators the only one who will know that. Or you know, limited few that will know that information. So again, we highly recommend coordinating with them for the success of your permitting project.

Steve: And you mentioned base flood elevation, which is a very important concept. And, you know, that minimum NFIP being building one foot above that base flood elevation. And that really gets at that idea of the floodway. You know, when you squeeze the floodway in, you don’t increase more than a foot anywhere. And so, even we’re floodways not delineated. You’ve got a little bit of, you know, hopefully you’re above that base, flood elevation, if you build to that, NFIP minimum requirement.

And I’ve seen communities go as high as four feet above that base flood elevation. And so, that concept of “Base Flood Elevation” is really important in establishing what the base flood elevation is on your property, is also important. Because these flood maps are, you know, you look at one flood map or look at it online. It’s a large area with cross-sections identified. Maybe in some cases several hundred feet apart, and that is where the elevation is shown.

And so it’s important to have what’s called an Elevation Certificate prepared by a surveyor. Where they will take the profile in the flood insurance study and actually figure out what’s the true base flood elevation for your property. So and Matt you’ve already touched on this some, but I do want to dive a little bit deeper into kind of this due diligence process of, you know, someone you want to buy house. As a homeowner that may be at or near a floodplain or maybe as a developer wanting to develop property. You know, let’s maybe talk through some of the things that we would want to look for and think about. And not let me start this conversation off by just mentioning a recent example that I’ve had and which a fairly recent flood insurance rate map was actually missing a large bridge and that was had been there for several years.

And so that had very large implications for this development because as you know, Matt a bridge like that would cause what’s called a Backwater Effect, you know, and these riverine hydraulics where it’s going to help to increase the base flood elevation upstream of it. And without that bridge in the model, the the flood maps, really weren’t accurate. And so that was a hurdle that we had kind of navigate through with our client. To bring the maps up to date and then figure out what. So now, where’s the real floodplain for the proposed development?

So, if you could speak some more to that due diligence process and your experiences with that

Matt: A lot of the things we do from a due diligence standpoint is, you know, I would typically jump onto FEMA’s flood map service center website. You can look up your particular property by address or by community. You know, if the maps are modern, you can get a heck of a lot of information just from that online search. You can create maps. You can print maps of your particular property or several properties or entire flooding reach. And we would start looking at. Okay. Is it, is it in a flood zone? If it is, what type of flood zone?

Steve and I have been talking about is it a Zone A? Is it a Zone AE? Is it a Zone X? There’s some other zones with the A letter with A0, A1, A2, A3, which are shallow flooded zones. And start with. Okay, where is the footprint of the proposed project, overlay that on those flood maps and start to look at what the potential impacts are. Would typically look at what the local flood plain regulations are to, you know, get back to what Steve was talking about. If the base, you know, if the minimum opening elevation for your project based on the base flood elevation plus free board is, you know, is it base BFE plus 3 foot? BFE plus one foot? That makes a huge impact on large developments. As far as what kind of earthwork you may need to do. Retaining walls? These kind of things.

So really a lot can go into a feasibility study from a floodplain impact standpoint. It just depends on the level of complexity of the project.

Steve: Yeah. Yeah, that’s a good point and just to reiterate the importance of sitting down with the local flood plain administrator during that due diligence process. Because as you mentioned earlier, they’re going to be more familiar with the localized flooding and maybe even some more recent flood studies. That have been done for other developments, that could be used as background information for something that you’re working on. So I guess we’ve talked about development. Talked about feasibility. I do want to talk just a little bit about this idea of revising the maps.

Matt, if you could just touch on maybe some of what goes into revising a map when you’ve got a development and how to, you know, take what FEMA has and assess the impact of your proposed development.

Matt: You know, a letter of map amendment is a pretty simple process to, again, make a request to FEMA for usually one particular property of one particular structure. You know, stating that, you know, we believe that it’s no longer in a flood zone. Typically for one of those, one of those simple reasons and that could balloon and complexity all the way to what we, you know, many times get involved in an actual map revision, letter of map revision. That could involve what’s called a Conditional Letter of Map Revision. Basically, doing a flood study to show what may happen if your project is developed the way you’ve designed it, making sure that it does meet the NFIP requirements. And then, having that reviewed and FEMA coming back and saying, “okay, we approve your conditional letter of map revision request, now you go out and build it. And you do a as-built survey and elevation certificate,” that Steve was talking about for any structure. Then you come back and do an update to the flood study that you originally did based on the as-built conditions and you submit what’s called a letter of map revision.

Basically showing that you’ve built the site within the permitting guidelines that were established from a floodplain development standpoint for a simple map change like a letter map amendment. You’re not physically changing the flood map. What you’re really doing is removing a small parcel or structure from the flood zone and memorializing it in a letter format. If you actually upload those approvals to the website, the FEMA Map Service website that I’d mentioned. So those will show up when you’re reviewing the maps but they won’t physically change the inundation zone in the map. What happens is when several you could have several map changes, you know through letter map amendments or letter map revisions.

That happen in a community over several years ago. And the actual flood zone and inundation zone shown on the map doesn’t get updated until the community goes for a full update of all their flood maps typically. And so when they go to update their maps for the entire community, all of those map changes, all those letter approvals, you know, letter map revisions those all get rolled up in the new maps and then they typically do those flood zones, do change to show that those structures are now outside of those flood zones.

Another thing that’s really important that we help our clients understand, is from a flood insurance standpoint, the requirement for flood insurance is actually the lenders choice. You know, the lenders responsibility to either require or not require flood insurance. And then if they do require flooding insurance, establishing those premiums. Like Steve and I were talking about earlier, and because of that, you it’s really important to talk for your clients to talk to their lenders and make sure they have a full understanding that, okay, if we’re going to move forward with the letter of map change or letter of map amendment or revision for this particular property. Will it in fact, either reduce my premiums required for flood insurance or eliminate the need for flood insurance?

That’s an important point. That is sometimes missed. Sometimes people think it’s obvious. It’s going to get removed, you know, as far as the requirement for flood insurance, and that’s not always the case. There’s some communities that just have persistent flooding historic, you know, property damage and risk involved where those premiums will not may not be eliminated. They may just be reduced.

Steve: Yes. I appreciate that. You’re careful explanation of all that Matt. and I guess the other thing I would just mention is we’ve talked about conditional letter of map revision and letter of map revision. That’s another key thing, it’s important to talk with the Local Flood Plan Administrator. Often, you know, well any time you submit something to FEMA the Local Flood Plan Administrator is going to have to sign a form as part of that MT1 and MT2 form. It’s a FEMA form that you complete in order to file one of these conditional letter of map revisions or a letter of map revision. Based on fill and FEMA is not going to review that until that local community has signed that form correctly.

Matt: Community Acknowledgment Form.

Steve: Yes. Thank you. I couldn’t think of the name of it. So this is not something that you do in a vacuum. You’ve got to do it in full knowledge of the local community. Well, thank you, Matt. That’s very helpful. So I feel like there’s so many different things that we could talk about this topic and get into the real granular level. But I hope this was a somewhat of an overview of what goes into. Well, not only what the National Flood Insurance Program is, but what goes into developing these flood insurance studies.

Do you have any final thoughts? Matt.

Matt: No, I just wanted to say, thanks again for inviting me, as you know and like you said, we’ve worked together for many many years here at CEC. And you know, so, you know how passionate I am about, you know, certified floodplain management and the work that we do on the engineering side and the technical side of what goes into the National Flood Insurance Program.

So again, you know, thanks for including me and, you know, I hope it was interesting and informative.

Steve: Yeah. Well, I have tremendous respect for you. As you know, you’ve helped me out many times over the years. I’ve learned a lot from you and we have several others in the company that couldn’t be on the podcast today. But we’ve got thankfully, a lot of, you know, we talked about professional engineering judgment earlier. A lot of that comes from having a lot of good professionals around to bat around some of these ideas and what we come across. So thank you again for your time today. Really appreciate it.

Matt: No problem Steve, thanks.

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