Flood Insurance in Sioux Falls: 5 Checks to Make Before You Write an Offer

Usually it gets skipped because everyone is focused on price, inspection, appraisal, financing, and getting the offer accepted. Flood and drainage questions often get pushed to the end.

The problem is that the lender’s flood determination may not show up until fairly late in the loan process. If the property is in a zone where flood insurance is required, that can create a last-minute scramble to find acceptable coverage, because the loan generally cannot close until the required policy is in place.

There is also an important distinction that sometimes gets blurred. A lender or real estate professional may say flood insurance is “not needed,” when what they really mean is that it is not required to close the loan. That does not mean the property has no flood risk. Whether a lender requires flood insurance and whether a property can actually flood are two different questions.

I have been working in flood insurance since 2015. Before that I spent about 20 years in advertising and creative work. When I got into insurance, I realized flood was this small corner of the industry that almost nobody wanted to explain clearly. I went the other direction and decided to specialize in it. Somewhere along the way, “Flood Nerd” stuck.

Better Flood is an independent flood insurance brokerage. We shop more than 40 flood insurance options, including the NFIP and private markets, and compare coverage, pricing, underwriting fit, and lender requirements for the individual property rather than assuming one company is always the best answer.

The first thing I would correct is the language. Every property is in a FEMA flood zone. What people usually mean is, “I’m not in one of the high-risk zones where my lender may require flood insurance.” Those are two different things.

FEMA currently reports that 29% of NFIP claims from 2014 through 2024 came from outside current high-risk flood areas. South Dakota’s Department of Public Safety also says approximately 25% of flood damage in the state occurs in low-risk zones.

That is why I worry about the false sense of security a map can create. A flood-zone designation is useful information, but it is not a guarantee of what water will do at an individual property. Development changes, grading changes, drainage changes, snowmelt, and heavy rainfall can all affect how water moves.

My advice is to get the quote even when coverage is optional. Maybe the buyer looks at the price and decides the protection makes sense. Maybe they decide they are comfortable keeping that risk themselves. Either way, they are making the decision with actual information instead of assuming “not required” means “cannot flood.”

Start with the exact address in FEMA’s Map Service Center. Confirm the building location, not just the parcel, and look at the effective map panel and flood-zone designation.

For Sioux Falls I would also look at the City’s floodplain mapping, because the City has locally regulated floodplain information in addition to FEMA’s regulated floodplain. The map is the starting point. If the structure sits close to a flood-zone boundary, that is when I want a better property-specific determination instead of eyeballing a map.

Think of FEMA flood zones as different levels on a map. A and AE are the higher-risk zones. If the home is in one of these zones and you have a federally backed mortgage, flood insurance is usually required. Zone X is generally lower risk. Flood insurance is usually not required by the lender, but that does not mean the home cannot flood.

The difference between A and AE is mostly about how much information FEMA has. AE has more detailed flood-elevation information. A is still considered high risk, but FEMA may have less detailed elevation data.

The easiest way to remember it: A or AE means higher risk and flood insurance is usually required with a mortgage. Zone X means lower mapped risk and flood insurance is usually optional. And “optional” does not mean “no risk.”

The lender is responsible for determining whether the building securing the loan is in a Special Flood Hazard Area. Most lenders use a third-party flood determination company and document the result on FEMA’s Standard Flood Hazard Determination Form. If the building is in an SFHA, the lender notifies the borrower that flood insurance is required.

That lender determination usually happens during the mortgage process, but a buyer does not have to wait that long to investigate. An agent, buyer, insurance broker, or flood-determination provider can review the property before the offer. I just would not represent that early review as the lender’s official determination.

No. “Levee-protected” means the levee reduces flood risk. It does not mean the risk is zero.

Sioux Falls has eight federally authorized levee systems protecting parts of the city from the Big Sioux River and Skunk Creek. Areas behind an accredited levee may be mapped outside FEMA’s high-risk flood area, which can mean the federal mortgage requirement for flood insurance no longer applies. But the levee, the FEMA map, and the lender requirement are three different things.

Under Risk Rating 2.0, NFIP pricing is also much more property-specific. FEMA looks at factors such as distance from a flood source, ground elevation, building characteristics, replacement cost, and levee-related risk. That means two homes behind the same levee can still have different premiums. If flood insurance is optional, I would still want to see what the coverage costs before deciding whether to go without it.

A Letter of Map Amendment, or LOMA, is basically asking FEMA to look at the actual elevation of the property and determine whether the structure sits high enough on natural ground to be removed from the mapped Special Flood Hazard Area. FEMA is generally comparing the lowest ground touching the structure with the mapped Base Flood Elevation. Certified elevation information is usually needed, often from a surveyor, and an Elevation Certificate is one way to provide it.

FEMA does not charge a review fee for a standard LOMA, but the survey or elevation work can cost money. There is also no guarantee FEMA will approve the request. A standard LOMA can take up to about 60 days once FEMA has all of the information it needs.

If FEMA approves the LOMA, it can remove the federal mandatory-purchase requirement. However, a lender can still require flood insurance even after a LOMA is issued. And removing the insurance requirement does not remove the possibility of flooding. The map is a regulatory tool, not a force field.

They are different mechanisms. River flooding from the Big Sioux or Skunk Creek can develop as water moves through a much larger drainage system. Heavy summer rain can create much faster runoff and overwhelm local drainage before the river itself becomes the main issue. Snowmelt can be more gradual, but it becomes a bigger concern when there is a large snowpack, frozen or saturated ground, and a quick warm-up. Ice can create localized backups by restricting normal river flow.

Sioux Falls says the Big Sioux River and Skunk Creek are its two primary flood sources. Historically, most river flooding there has occurred during March and April with snowmelt, while rainfall flooding has commonly occurred in June.

What that event showed me is how quickly “unlikely” can turn into “happening now.” The National Weather Service documented widespread rainfall totals of 5 to 10 inches, with some areas of southeast South Dakota and northwest Iowa receiving 10 to 20 inches. Sioux Falls recorded 6.70 inches over the three-day period, and record flooding occurred at 25 river points across the broader region.

From an insurance standpoint, the lesson is simple: you cannot wait until the water is coming to start thinking about flood insurance. Once an event is underway, waiting periods, underwriting restrictions, and private-market moratoriums can make it too late to put coverage in place for that event. Flood insurance should be considered as part of the protection plan before there is an immediate threat, not after.

It can, but the cause of the water matters. Under the NFIP, a “flood” generally means water covering at least two acres of normally dry land or affecting at least two properties, including yours, because water rose, overflowed, or rapidly accumulated on the ground.

So if a storm overwhelms the street drainage, water rises across the yard, and that water then pours into a window well, that may qualify as a flood. But if the water collected in the window well because a downspout was broken, missing, or dumping water next to the foundation, that may be treated very differently. When the adjuster comes out, one of the first questions is going to be: what actually caused the water to get there?

The simple version is: water in the basement does not automatically mean “flood.” You have to trace where the water came from and what caused it to enter the home.

I would ask very directly: Has water ever entered the basement? How often does the sump run? Has the sump ever failed? Is there drain tile? Have there been repairs related to water? Have there been sewer backups? Has water ever sat in the yard for an extended period? And have there been insurance claims for water or flood damage?

South Dakota’s current disclosure form gets pretty specific. It asks about water penetration in the basement or crawl space, water-damage repairs, unrepaired water damage, drain tile, past flood damage, insurance claims, sewer backup, sump pumps, and whether water has remained in the yard for more than 48 hours. That disclosure is valuable, but it is not a substitute for an inspection. The state says that directly on the form.

This is one of the biggest surprises for homeowners. NFIP basement coverage is limited to a specific list of items. It generally covers things like the furnace, water heater, electrical equipment, sump pump, foundation components, and unfinished drywall. If contents coverage is purchased, there is also limited coverage for certain items such as a washer, dryer, freezer, and portable air conditioner. But finished flooring, finished walls, furniture, electronics, and most other contents in a finished basement are not covered.

Private flood insurance can be different. Some private policies offer broader basement coverage or an endorsement that provides additional protection. But those options are not available on every property, and the coverage varies considerably by carrier. If you have a finished basement and protecting it is important to you, tell your flood insurance broker up front, so we can look specifically for carriers that offer better basement coverage for that property rather than simply comparing premiums.

This is where I would bring in the buyer’s homeowners agent. A sump pump failure or sewer backup by itself is not automatically a flood claim, and the coverage on the homeowners side can depend on the policy form and any water-backup or sewer-backup endorsements that were added.

A flood policy responds when the loss meets that policy’s definition of flood. Homeowners coverage handles a different set of water losses, and sewer or drain backup often requires a separate endorsement with its own limits and deductible. So I would have the buyer ask their homeowners agent very directly: “Do I have water-backup or sewer-backup coverage, what is the limit, what triggers it, and is that enough for a finished basement?”

I would be careful publishing a Zone X-versus-AE price range, because Risk Rating 2.0 does not price a property from the flood-zone letter alone. I can find relatively inexpensive AE properties and more expensive Zone X properties depending on the home and location. I would rather tell a buyer, “Give me the address and let me price the actual property,” than give them a broad range that creates a false expectation.

On the Sioux Falls policy statistics, I would add an important qualifier. The available public policy counts come from the NFIP, so they represent government flood policies only, not the private flood market. The older report showed 418 Sioux Falls policies in force in 2018, but the current FEMA reporting system uses a different geographic methodology, so I would be cautious about comparing the old and new counts as though they show a clean trend. If we use a policy count or average premium in the article, I would label it specifically as NFIP data and include the as-of date.

For most new NFIP policies purchased voluntarily, there is a 30-day waiting period before coverage takes effect. One major exception is when flood insurance is being purchased in connection with making, increasing, extending, or renewing a mortgage. In that situation, coverage can generally take effect in connection with the loan closing.

The private market can work differently. Some private flood carriers have shorter waiting periods than the NFIP, and some may allow coverage to begin in connection with a loan closing. Private carriers may also impose a temporary moratorium when a major storm is approaching. So even if a private policy normally has a shorter waiting period, that does not mean you can wait until a major rain event or other flood threat is already on the way. Insurance works best when you make the decision while the weather is quiet, not when the risk is already at the door.

I do not treat NFIP versus private flood as a religion. I compare both when both are available and look at what actually fits the property and the homeowner.

The NFIP is very standardized. For a typical one-to-four-family home, the maximum building limit is generally $250,000, with up to $100,000 for contents. Basement coverage is limited, and the NFIP does not provide additional living expense coverage. Private flood insurance can offer building and contents limits well above the NFIP maximums, which can be important when the realistic cost to rebuild the home is greater than $250,000. Depending on the carrier and property, private policies may also offer additional living expense coverage, broader basement protection, and higher contents limits.

But private flood insurance is not one standardized product. Coverage, underwriting, deductibles, waiting periods, cancellation provisions, refunds, and lender acceptance can all vary by carrier. An NFIP policy generally cannot simply be canceled midterm because the homeowner changes their mind; FEMA allows cancellation only under specific qualifying circumstances. Private carriers have their own rules. The right answer depends on the home, its replacement cost, the basement, the lender requirements, and which private carriers are willing to insure that particular property.

The NFIP is currently authorized through December 11, 2026. If Congress allows the NFIP’s authority to lapse, FEMA generally cannot issue new NFIP policies until the program is reauthorized. Existing policies do not simply disappear, and existing claims can still be handled, but new purchases and some renewals can become much more complicated.

There can also be some exceptions and workarounds depending on when the application and premium were submitted, whether an existing seller policy can be assigned to the buyer, and what the lender will accept. The private market is not dependent on congressional authorization, so a lapse does not shut down private flood insurance. That is one reason I like comparing NFIP and private coverage from the beginning instead of waiting until a closing is caught in an NFIP authorization issue.