A floodplain is an area located adjacent to a stream or a lake or a depressional area that may be periodically covered by water up to a certain elevation. This elevation is known as the Base Flood Elevation (BFE) and is used to determine whether a site is in a floodplain.
The Federal Emergency Management Agency (FEMA) floodplain maps can be used to make a preliminary determination of the presence of a floodplain or floodway. You may also contact the Building & Engineering Division at 847.377.2600 to obtain a preliminary determination of the presence of a floodplain on a property.
Requirements for development in the floodplain:
- Flood-proofed material required below the Flood Protection Elevation (FPE)
- Flow-through vents required in the foundation
- A topographic survey may be required to determine the existence/limits of the floodplain
- An elevation certificate / flood-proofing certificate may be required
For detailed information on the requirements of floodplain development, please call 847.377.2600
Elevation Certificate/Floodproofing Certificate
An Elevation Certificate is FEMA form that is used to certify the elevation to which a building has been constructed.
A Floodproofing Certificate is a FEMA form that is used to certify that a building has been designed and constructed to be structurally flood proofed to the flood protection elevation.
An Elevation Certificate/Floodproofing Certificate, must meet the following requirements:
- Both certificates can be completed by an Architect or an Illinois Registered Professional Engineer.
- An Elevation Certificate can also be completed by an Illinois Licensed Land Surveyor
- Both certificates shall be submitted and approved by the Building & Engineering Division prior to requesting a certificate of occupancy inspection.
Specific elevations required are determined prior to permit issuance and are indicated on the approved plans.
Use this link to access FEMA's Elevation Certificate Form
Use link to access FEMA's Floodproofing Certificate Form