What is a floodplain?
How do I determine if my property is within a floodplain?
Floodplain areas are designated by FEMA on the Flood Insurance Rate maps (FIRMS). You can search the flood maps in your area using FEMA’s Map Service Center to create a FIRMette, or contact our office to determine if your property is within a floodplain. You can also view Idaho Department of Water Resource’s (IDWR) digital flood hazard interactive maps.
There are areas of Valley County with possible but undetermined flood hazards where flood hazard analyses have not been conducted. If you are unsure as to whether your property is located in a floodplain, please contact our office.
Can I build in the floodplain?
Can I do any grading, excavation, or filling in the floodplain?
When is a floodplain permit necessary?
Can I alter a watercourse?
Are there special requirements pertaining to areas around the floodplain?
What is Base Flood Elevation (BFE)?
What are the types of areas within FEMA's flood insurance rate maps (FIRMS)?
Flood zones are the geographic areas that FEMA has defined according to varying levels of flood risk. The following chart gives a brief description of the zones that are present In Valley County.
|Areas outside of the 1-percent annual chance floodplain|
|Areas susceptible to flooding, but detailed elevations and hydrologic calculations are not available. An Elevation Certificate, prepared by a professional surveyor licensed in the State of Idaho, is required for building.|
|Areas with a 1-percent annual chance of flooding. Base flood elevations derived from detailed analyses are shown at selected intervals within this zone.|
|River or stream flood hazard areas, and areas with a 1-percent or greater annual chance of shallow flooding, usually in the form of sheet flow, with an average depth ranging from 1 to 3 feet.|
|Areas with possible but undetermined flood hazards. No flood hazard analyses have been conducted|
How can I help maintain the floodplain on my property?
Maintaining the flow capacity in streams that cross properties requires cooperation and assistance to prevent flooding and bank erosion.
Do not dump or throw anything into ditches or streams: Trash and vegetation dumped into a stream degrades water quality and every piece of trash contributes to flooding.
Will I need to obtain permits from any other agencies?
State and federal agencies may also require permits prior to approval of your building permit or floodplain permit application with Valley County. It is your responsibility to obtain any necessary permits and approvals.
The following agencies may require permits and offer a joint application process:
- Idaho Department of Water Resources – 208-334-2190
- U.S. Army Corps of Engineers – Boise Field Office – 208-345-2286
- Idaho Department of Lands – 208-334-3488
Additional agencies may also require approvals or permits. This includes but is not limited to: Idaho Department of Environmental Quality and the Environmental Protection Agency.
What is the penalty if I don't obtain the property permits?
Failure to obtain the proper permits before you begin work can result in enforcement action by Valley County and/or other agencies, including at a minimum:
- Corrective action
- Monetary penalties
- Criminal indictments and imprisonment
My permit has conditions of approval; what does that mean?
If your application is approved, you may complete the approved work based on meeting conditions of approval, as determined by the Valley County Flood Plain Coordinator. These conditions may include submittal of elevation certificates.
Check your permit conditions carefully. Feel free to contact the Valley County Flood Plain Coordinator at 208-382-7115 if you have any questions regarding your permit.
What is an elevation certificate?
What is no-rise certification?
Planning and Zoning Director
and Floodplain Coordinator
P & Z Commissioners:
219 North Main Street
PO Box 1350
Cascade, ID 83611