Is my property in a floodplain?

There are two different types of floodplain in Sioux Falls:

1.  FEMA regulated floodplain

To check this data go to FEMA's Map to search an address.

2.  City of Sioux Falls locally regulated floodplain (includes all FEMA regulated floodplain)

To check this data go to Flood Restriction in the City open data page to search an address. The City takes a conservative approach for floodplain regulations and by default considers a whole property within the floodplain even if only a small portion appears to be within the floodplain on the map. 

What does it mean if my property is in the floodplain?

All property within a floodplain have additional restrictions that apply for property improvement depending on the situation. Here are some of the most common situations:

1. Property has floodplain in the yard that just touches or crosses the property line:

By default the property is considered completely within the floodplain by the City. Additional details can be provided to the City to show that the building, property, or part of the property should be considered out based on the ground level. These usually require a surveyor or engineer to complete a Elevation Certificate (EC) or a site plan to be turned into the City. 

2. Property is outside the floodplain but within 100 feet:

The City's buffer yard restrictions require any building used for residential (House, Apartment, Condo, Mixed-Use building, Etc.) to meet specific conditions for any building within 100 feet of any City regulated floodplain if the lot was platted after August 25, 2016. For new construction or additions with basements these properties need meet the standards set by the ordinance, such as no basement within 20 feet of the floodplain, no basement floor lower than 5 feet below the Base Flood Elevation (BFE), and no basement openings less than 1 foot above the BFE. 

3. Property clearly within the floodplain area:

The City's standards for new or substantial construction in these areas require the top of the lowest floor and all utilities be at least 2 feet above the Base Flood Elevation (BFE). For work on existing buildings, each permit's value is compared to the building value at the time of improvement to get a percentage and is tracked for 3 years from the date of issuance. When a new permit is requested, all permit percentages within a 3-year period are added together and if the total percentage is 45 percent or greater then the whole building will need to meet current standards. Typically this can mean removing a basement and/or raising the building, but it can result in needing to completely reconstruct a building. 

In addition, to buildings the City also regulates digging and filling within the floodplain. Any proposed fill within the floodplain will be required to provide compensatory storage. This means that for any amount of fill being proposed in the floodplain the same amount of earth or more will need to be removed from the same area so that during a flood generally the same amount of water can be stored. Please reach out to the floodplain staff with any specific questions.

4. Property clearly not within the floodplain area:

No floodplain restrictions are applicable! Please check with the Building Services and Zoning departments for required building and zoning permits on all projects. 

 

Is floodplain insurance required?

The City of Sioux Falls does not make floodplain insurance requirement determinations. Those decisions are most commonly made by a property's lending institution. The property owner may need to hire a surveyor or engineer to complete a Elevation Certificate (EC) and then obtain a letter from FEMA showing that the property is reasonably safe from flooding. The City may also have property details on file to help with this process.  

Maintain Your Property

Regular maintenance of property and drainage systems can prevent or limit flooding during an event. Work with neighbors to identify where excess rain and snowmelt will likely go and see if there are spots that could cause private property damage. Make sure things are secured to your house so that they aren’t blown away in a high wind. Check that downspouts are far enough away from your house that water pool next to your foundation for any period of time. 

More substantial modifications could be necessary to protect your structure from flooding. You can always reach out with questions to our floodplain team at floodplain@siouxfalls.gov. We may be able to provide some guidance including when a permit for floodplain or building improvements is needed. Some examples of projects that may need permitting are: installing a berm, regrading the property, replacing windows and doors with more flood resistance versions, or elevating the structure. FEMA offers a detailed look into six ways to protect your home from flooding in this PDF guide. 

For temporary emergency modifications you can generally begin the installation without a permit. Please feel free to reach out to verify if your temporary project meets the criteria for this emailing our floodplain team at floodplain@siouxfalls.gov.

Examples of temporary projects needed to prevent flooding:
  • installing a temporary berm,
  • stacking sandbags or other water barrier options,
  • temporarily sealing building openings,
  • elevating major appliances.

Download your copy of the PDF FEMA guide

If you notice any illegal dumping in the drainage areas you can report it. You can use an app or the City’s website. Select "Public Works and then = Drainage Concerns” and then select the area and add any pictures or comments and send it in. You can also go below the map and submit text-only information instead.