A dry wash running across a parcel can look like a nice feature in listing photos. It’s also a drainage channel, and in the desert it can fill fast. Before you buy land in Mohave County, check two things: where the parcel sits on FEMA’s flood map, and whether a wash or a mapped floodplain limits where and how you can build. The county will look up a parcel’s flood zone for you.
Key Takeaways
– Every property is in a flood zone. What matters is whether it’s in a Special Flood Hazard Area.
– In unincorporated Mohave County, new construction, grading, solid walls and fencing in that area need a county Floodplain Use Permit. Inside a city, ask the city which office handles floodplain permits.
– Federally regulated and federal agency lenders can’t make a loan on a building there without flood insurance. A new policy usually takes 30 days to start, with no wait when it’s bought with a mortgage.
What is a wash, and why does it matter on desert land?
A wash is a channel that sits dry until it rains, then carries the runoff. The Mohave County Flood Control District warns that heavy rainfall miles away can send a torrent of water down a wash “in just a matter of minutes.” That’s a flash flood, and it can arrive when it isn’t raining where you stand.
For a buyer, that decides some practical things. Water runs down the channel in a storm, so the building site needs to sit clear of it. If the driveway or access road crosses a wash, you’ll want a plan for storm days. The county is blunt about it: it’s never safe to drive across a flooded wash, and just two feet of water can float a vehicle.
You also can’t simply fill a wash or wall it off. Under A.R.S. 48-3613, with limited exceptions, a person may not engage in development that will “divert, retard or obstruct the flow of waters in any watercourse” without written authorization from the flood control district’s board. The county adds that before any improvements, even on private land, you must first find out whether the land is in a FEMA Special Flood Hazard Area.
Comparing several parcels? Our guides to buying acreage in Mohave County and to lot splits and land divisions cover the other checks that go with this one.
What do FEMA’s flood zones mean?
FEMA’s flood maps sort land by flood hazard. The high-risk area is the Special Flood Hazard Area, which FEMA defines as the land a flood with a 1 percent chance of being equaled or exceeded in any given year would cover. That flood is also called the base flood, or the 100-year flood.
That name trips people up. The county’s Flood Control District explains that the 100-year flood describes a flood’s size, not a time period, and an area can see a 1 percent flood several times in one year, or not at all.
Zones on the maps, using the Mohave County labels and FEMA’s definitions:
| Zone on the map | What it means |
|---|---|
| A, AO, AE, AH | Special Flood Hazard Area: the 1 percent annual chance flood |
| Shaded X | Moderate hazard, between the base flood and the 0.2 percent annual chance (500-year) flood. Risk is reduced, not removed |
| X (unshaded) | Minimal hazard, above the 500-year flood. Risk is reduced, not removed |
| D | Undetermined: no flood-hazard analysis has been done, but the county says a flood risk still exists |
How do you look up a parcel’s flood zone in Mohave County?
Start with the Flood Control District’s FEMA Flood Map Viewer. The county says you can search it by name, address or parcel number (APN) and see where the Special Flood Hazard Areas sit in relation to the property.
You can also check three other ways:
- Use FEMA’s Map Service Center, where the county says anyone can see where a property lies relative to a Special Flood Hazard Area and print a small map extract called a FIRMette.
- Ask Mohave County to mark your parcel on a FIRMette. Send the request to [email protected].
- Request a Property Floodplain Information document. Email the Flood Control District the parcel number or street address, plus your email and phone number, and the county says the report comes back within a few days.
Online risk tools are a different thing. The county notes that the result from FEMA’s FloodSmart risk tool isn’t an official FEMA determination. For virtually every mortgage on a structure, the lender checks the community’s effective flood map, so go by that map.
Buying from a seller of five or fewer parcels of land, other than subdivided land, in an unincorporated area? The seller’s affidavit of disclosure under A.R.S. 33-422 asks, at item 6, whether any part of the property is in a FEMA designated regulatory floodplain.
Do you need a permit to build near a wash or in a floodplain?
In a Special Flood Hazard Area in unincorporated Mohave County, yes. The county requires a Floodplain Use Permit for any change to land there, including new construction, additions, grading, and solid walls or fencing. New buildings and substantial improvements there also need an Elevation Certificate. Outside that area, work that would divert, retard or obstruct a wash still needs written authorization under A.R.S. 48-3613, apart from its limited exceptions. Inside city limits, the city may handle floodplain permits instead. Bullhead City, for one, says it provides information and services related to FEMA-designated floodplains and lists its own floodplain permit.
In unincorporated Mohave County, you won’t file with the Flood Control District separately. At the county’s One Stop permit shop you apply for the permits you need at one time, and the district reviews each application for floodplain compliance. One Stop offices include 3250 E Kino Ave in Kingman and 1130 E Hancock Road in Bullhead City, and the county lists the district’s overall review time as 20 working days.
A few rules shape what you can build:
- The county explains that Arizona requires structures in a Special Flood Hazard Area to sit at least one foot above the Base Flood Elevation, the level floodwater is expected to reach in the base flood. That line is the Regulatory Flood Elevation.
- A Zone AE floodway shows on the map as blue and white diagonal stripes. Building there carries special requirements under Section 5, Article 7 of the Mohave County Flood Control Ordinance.
- Under A.R.S. 48-3609, waste disposal systems can’t be installed wholly or partly in a regulatory floodway. Our well and septic guide covers the rest of the septic process.
- That statute also calls for regulations requiring every new placement of a mobile home to be anchored against flotation, collapse or movement.
Questions about a specific parcel go to the Flood Control District at 928-757-0925.
When does a lender require flood insurance?
When the building is in a Special Flood Hazard Area and the loan comes from a federally regulated lender or a federal agency lender. Under 42 U.S.C. 4012a, those lenders may not “make, increase, extend, or renew any loan secured by improved real estate or a mobile home” in that area, where flood insurance is available, unless the building is insured for the term of the loan.
- If you pay cash, no lender is involved, so this rule isn’t what decides whether you insure. If you’re financing land with nothing on it yet, ask your lender how the rule applies to your loan.
- The same statute says flood insurance isn’t required for a structure on residential property that’s detached from the main residence and doesn’t serve as a residence.
- When a lender finds a building isn’t insured, it notifies the borrower. If the borrower doesn’t buy coverage within 45 days, the lender buys it and can charge the borrower.
- Under 42 U.S.C. 4013, new coverage generally takes effect after 30 days. FloodSmart lists exceptions, including no wait when you buy the policy while making, increasing, extending or renewing a mortgage.
- To get the required insurance on a building in a Special Flood Hazard Area bought with a federally backed mortgage, the county says you need an Elevation Certificate, certified by an Arizona licensed land surveyor or engineer.
Why think about it outside the high-risk zone? FloodSmart says 1 in 3 flood insurance claims come from low- and moderate-risk zones, and most homeowners insurance doesn’t cover flood damage. Inside a Special Flood Hazard Area, the county’s flood safety page puts the chance of flood damage over a 30-year mortgage at 26 percent, against 4 percent for fire. For homeowners, National Flood Insurance Program building coverage runs up to $250,000 and contents coverage up to $100,000.
Can a flood zone designation be changed?
Sometimes. If a structure or parcel is on naturally high ground that wasn’t raised with fill, FEMA can issue a Letter of Map Amendment (LOMA) stating the base flood wouldn’t reach it. Ground that has been raised with fill goes through a Letter of Map Revision Based on Fill (LOMR-F) instead.
If FEMA grants the change, FEMA says the owner may no longer be required to pay for flood insurance and can send the letter to the lender. An Elevation Certificate supports that request. Federal law also lets a borrower and lender jointly ask FEMA to review a determination, with an answer due within 45 days.
Flood and wash checklist for Mohave County land
Work through this during your due-diligence period, before it runs out:
- Look up the parcel on the county’s FEMA Flood Map Viewer by APN, and write down the zone.
- Email [email protected] for a Property Floodplain Information document.
- Walk the parcel and note every wash, including any the driveway or access road would cross.
- If the building site, driveway or any grading falls in a Special Flood Hazard Area in unincorporated Mohave County, plan on a Floodplain Use Permit, plus an Elevation Certificate for any new building there. Inside a city, ask the city which office handles it.
- Keep the septic site out of any regulatory floodway.
- Check the county’s map viewer for an existing Elevation Certificate. Not every certificate on file is posted there.
- If you’re financing a building or a manufactured home, ask the lender about flood insurance early.
- If the seller is selling five or fewer parcels of land, other than subdivided land, in an unincorporated area, read item 6 of the affidavit of disclosure.
- If a mapped parcel sits on high ground, ask a land surveyor or engineer whether a LOMA is worth pursuing.
- Don’t fill, wall off or reroute a wash without written authorization.
Water supply is the other question to settle early on desert land; see our guide to water rights. For power off the grid, read off-grid solar in Mohave County, and for Golden Valley specifically, buying land or a home in Golden Valley. Or browse land for sale in Mohave County.
Frequently asked questions
Is my Mohave County land in a flood zone?
Every property is in some flood zone. What matters is whether it’s in a Special Flood Hazard Area, shown as Zone A, AO, AE or AH on Mohave County’s maps. Search the parcel number on the county’s FEMA Flood Map Viewer, or email [email protected] for a Property Floodplain Information document.
Do I need flood insurance if I pay cash?
The federal requirement applies to loans from federally regulated and federal agency lenders, so a cash purchase doesn’t trigger it. The choice is yours. Most homeowners insurance doesn’t cover flood damage, and FloodSmart says 1 in 3 flood insurance claims come from low- and moderate-risk zones.
Can I build across or fill in a wash?
Not without approval, apart from limited exceptions. A.R.S. 48-3613 requires written authorization from the flood control district’s board for development that would divert, retard or obstruct a watercourse. In a Special Flood Hazard Area in unincorporated Mohave County, grading, solid walls and fencing also need a Floodplain Use Permit. Call the Flood Control District at 928-757-0925 first.
What is a Letter of Map Amendment?
A LOMA is FEMA’s letter that an existing structure or parcel on naturally high ground, not raised with fill, wouldn’t be flooded by the base flood. If FEMA grants it, the owner may no longer be required to carry flood insurance and can send the letter to the lender.
Talk to the team
If you’re weighing a parcel and want to talk through what to check, call The Hassell Team, Keller Williams Arizona Living Realty, at (928) 715-7653, or contact us. The team has 20+ years in Mohave County.
Sources
- FEMA, Flood Zones (glossary), retrieved 2026-10-14, https://www.fema.gov/about/glossary/flood-zones
- FEMA, Change Your Flood Zone Designation, retrieved 2026-10-14, https://www.fema.gov/flood-maps/change-your-flood-zone
- FEMA National Flood Insurance Program, Buy a Flood Insurance Policy, retrieved 2026-10-14, https://www.floodsmart.gov/get-insured/buy-a-policy
- FEMA National Flood Insurance Program, What is my Flood Zone, retrieved 2026-10-14, https://www.floodsmart.gov/flood-zones-and-maps/what-is-my-flood-zone
- Mohave County Flood Control District, Is my property in a Flood Zone, retrieved 2026-10-14, https://www.mohave.gov/departments/development-services/flood-control-district/floodplain-administration/is-my-property-in-a-flood-zone/
- Mohave County Flood Control District, Permitting, retrieved 2026-10-14, https://www.mohave.gov/departments/development-services/flood-control-district/floodplain-administration/permitting/
- Mohave County Flood Control District, Elevation Certificates, retrieved 2026-10-14, https://www.mohave.gov/departments/development-services/flood-control-district/floodplain-administration/elevation-certificates/
- Mohave County Flood Control District, FEMA and NFIP, retrieved 2026-10-14, https://www.mohave.gov/departments/development-services/flood-control-district/public-information/fema-and-nfip/
- Mohave County Flood Control District, Flood Myths, retrieved 2026-10-14, https://www.mohave.gov/departments/development-services/flood-control-district/public-information/flood-myths/
- Mohave County Flood Control District, Flood Safety, retrieved 2026-10-14, https://www.mohave.gov/departments/development-services/flood-control-district/public-information/flood-safety/
- U.S. Code, 42 U.S.C. 4012a (flood insurance purchase requirements), govinfo, retrieved 2026-10-14, https://www.govinfo.gov/content/pkg/USCODE-2023-title42/html/USCODE-2023-title42-chap50-subchapI-sec4012a.htm
- U.S. Code, 42 U.S.C. 4013 (waiting period), govinfo, retrieved 2026-10-14, https://www.govinfo.gov/content/pkg/USCODE-2023-title42/html/USCODE-2023-title42-chap50-subchapI-sec4013.htm
- Arizona Revised Statutes 48-3609, Arizona State Legislature, retrieved 2026-10-14, https://www.azleg.gov/ars/48/03609.htm
- Arizona Revised Statutes 48-3613, Arizona State Legislature, retrieved 2026-10-14, https://www.azleg.gov/ars/48/03613.htm
- Arizona Revised Statutes 33-422, Arizona State Legislature, retrieved 2026-10-14, https://www.azleg.gov/ars/33/00422.htm
- City of Bullhead City, Floodplain, retrieved 2026-10-14, https://www.bullheadcityaz.gov/business-development/building-and-renovating/floodplain/