Public Works

Floodplain Development Permit

Floodplain Development Permits are required for development within the city of Henderson to ensure the proposed project meets the requirements of the National Flood Insurance Program (NFIP) as well as the local Clark County Regional Flood Control District (CCRFCD) Hydrologic Criteria and Drainage Design Manual Requirements. 

A permit is required for all development in the Special Flood Hazard Area (SFHA) as shown on our Flood Insurance Rate Map (FIRM).

A SFHA is the 100-year flood zone or a typically dry land area that is temporarily inundated with storm water runoff from a large rain storm. 

The Flood Insurance Rate Map (FIRM) is a map prepared by the Federal Emergency Management Agency(FEMA) that identifies the 100-year flood zones and other information needed in order to protect new development from flood damage.

So what does this mean and why is it important? One simple word: money.

The NFIP underwrites flood insurance coverage only in the communities that adopt and enforce floodplain regulations that meet or exceed NFIP criteria. The City of Henderson is just such a community. Buildings and homes built in accordance with these regulations have a lower risk of being flooded and can be insured at lower rates.  By going through the permitting process the property is protected from flooding and lower flood insurance rates are available to the community.

Submitting a drainage study is the first step in the permitting process at the City of Henderson.

A drainage study is a technical document prepared by a registered engineer.  Storm flows that impact the site are identified and are used to design the appropriate flood control facilities to ensure that any new homes and other buildings are protected from flooding.  Once the drainage study has been approved, civil improvement plans are submitted and approved, building permits are issued and construction can begin. 

So what happens if the development is in a 100-year flood zone?  The NFIP regulations do not allow for a proposed development to encroach within a 100-year flood zone which will cause an increase of more than one foot of the 100-year flood water surface (Base Flood Elevation).  In addition, the regulations require that the developer apply to FEMA for a Letter of Map Revision (LOMR) to let FEMA know that the topography of the area is changing and the flood map has to be updated.  Once FEMA has accepted the application and all of the technical analysis then a LOMR is issued and the flood zone is changed.