The flood maps and zones around the bay
Lots at the water's edge are often in a FEMA special flood hazard area, the zones where flood rules apply. Mobile County's current map took effect June 5, 2020. Mobile County code amendments Baldwin County's took effect April 19, 2019. FEMA Community Status Book
FEMA had posted no new draft map for Mobile County as of November 4, 2026. FEMA preliminary flood layer The zones you will see:
- VE: coastal high hazard, where waves add to still water.
- AE: flood zone with a printed base flood elevation, or BFE (the 1 percent yearly flood height).
- Coastal AE: AE ground where waves reach 1.5 feet. Some towns treat it like VE.
- Shaded X: a 0.2 percent yearly chance. Some towns count it as flood hazard.
- X: minimal hazard.
Baldwin County's map also holds AO and A zones, plus 35 wave-line features. FEMA flood layer, Baldwin County VE elevations run 11 to 20 feet in Mobile County and 10 to 18 feet in Baldwin County. FEMA flood layer, Mobile County FEMA flood layer, Baldwin County
Flood zones at named Mobile County sites
What is the flood zone and base flood elevation of my Mobile County lot?
It depends on the stretch. Sampled points on the western shore run from VE 19 feet at Shell Belt Road to plain Zone X on upland bluffs. Elevations are in feet NAVD88.
| Site | Zone | Elevation |
|---|---|---|
Shell Belt Road, Bayou La Batre launch | VE | 19 ft |
Coden Belt Road | VE | 17 ft |
Dauphin Island Parkway, north of Heron Bay | VE | 15 ft |
Mon Louis Island bay shore | VE | 12 to 13 ft |
Mobile bay front, Brookley to Arlington | VE at water, AE behind | VE 14 to 15, AE 10 to 13 |
Lower Dog River near the bay | VE near bay, AE upriver | VE 13 to 14, AE 10 to 12 |
Hollinger's Island, end of Hammock Road | AE | 11 ft |
Deer River Road | AE | 11 ft |
Fowl River Marina, north of the bridge | AE | 12 ft |
Delta Port Marina, Coden | AE | 12 ft |
Bayou La Batre Bridge | AE | 15 ft |
Chickasaw Creek near Chickasaw | AE | 11 to 12 ft |
North Salt Aire and Utopia Club bluffs | X | No BFE |
Sources: FEMA flood layer, sampled sites; FEMA flood layer, bay front; FEMA flood layer, Dog River; FEMA flood layer, upper river; FEMA flood layer, Salt Aire
The Eastern Shore is different. North of Fairhope, FEMA's Katrina study found marks above 13 feet NAVD88, and a bluff limited how far the surge went inland. At the far end of Bon Secour Bay the marks fell as low as 5 feet. FEMA Katrina high-water marks
Look up your own lot on FEMA's map, or ask the local floodplain office for the panel and BFE. Use the Mobile County hub or the Eastern Shore and Baldwin County hub to find that office.
Freeboard by community
How much freeboard does each community require?
Freeboard is extra height above the BFE. Rules differ town by town, and two bay neighbors can differ by a full foot.
| Community | Freeboard above BFE | Status |
|---|---|---|
City of Mobile | 1 ft; code sets floor at BFE | Encouraged |
Creola | 1 ft in A zones | Required |
Bayou La Batre | 2 ft; V zones 1 ft to lowest beam | Required |
Dauphin Island | 2 ft | Required |
Baldwin County permit area | 1 ft in A, V and Coastal A | Required |
Daphne | 1 ft in its flood definition | Required |
Fairhope and Spanish Fort | Not confirmed (Ord. 1643; 540-2019) | Ask the city |
Unincorporated Mobile County | Current figure not confirmed | Ask the county |
Saraland, Satsuma, Chickasaw, Prichard | Ordinance text not found | Ask the city |
Sources: Mobile flood permit form; Creola Ordinance 2020-003; Bayou La Batre Ordinance 2020-002; Dauphin Island Ordinance 105; Baldwin County flood page; Daphne LUDO Article 11; Fairhope Ordinance 1643; Spanish Fort ordinance list
Dauphin Island has required its extra 2 feet since Katrina in 2005. Dauphin Island Ordinance 105 Baldwin County's rule covers the unincorporated permit area plus Elberta, Magnolia Springs and Perdido Beach. Baldwin County Floodplain Development Ordinance
In the City of Mobile, the one-foot figure is only encouraged on the permit form. It is based on the worst flood zone anywhere on the lot, not just under the house. Mobile flood permit form
Coastal AE, boathouses and shaded X
How is coastal AE treated in Mobile?
Mobile treats coastal AE the same as VE. The ordinance covers the strip between the 1.5-foot wave line and the V-zone edge, and V-zone building rules apply there. Mobile City Code Secs. 17-2 and 17-29
Those rules bite on boathouses and sheds. Mobile bars accessory buildings below BFE in VE, V and coastal AE zones, and boathouses are named in the code. Mobile City Code Sec. 17-27(15) Bayou La Batre bans them the same way. Bayou La Batre Ordinance 2020-002
What does Baldwin County add?
Baldwin County adds its own V-zone limits. Fill cannot support a structure, foundations must be piles or columns unless approved, and no solid walls may sit below BFE plus 1 foot. Baldwin County V-zone rules
Before you plan an over-water boathouse, ask the floodplain office in writing how it treats one. The sources above name the ban but do not say how each office reads it for structures over the water.
Does shaded X count?
In the City of Mobile it does. The land disturbance guide counts V, VE, A, AE and shaded X as the flood hazard area. Mobile Land Disturbance Permit Guide A flood development permit is required there. Mobile flood development permit
Dauphin Island draws the line elsewhere. Only AE and VE fall in its flood overlay, and Zone X does not. Dauphin Island Ordinance 105
Flood permits for marine work
When does a flood zone trigger a county permit?
In unincorporated Baldwin County, a pier, dock, boathouse or bulkhead needs a county flood permit only when it lies in a FEMA flood hazard area. Elsewhere the county asks for none, though other agencies may. Baldwin County marine accessory checklist The fee is $75. Baldwin County fee schedule
Mobile County asks for a flood elevation certificate, or a waiver, when a lot is in a flood zone. Mobile County permit checklist Work in a flood area also needs a Permit to Develop. Mobile County stormwater plan
The county pages do not say whether a private bulkhead or pier triggers a county permit. Call Mobile County Building Inspections and get the answer in writing. See the permit guide for the state and federal layer.
Substantial damage rules
What counts as substantial damage?
Substantial damage is repair cost of 50 percent or more of a building's value. If your home crosses that line, it must be brought up to current flood rules. The tests differ:
- City of Mobile: 50 percent, plus repetitive loss (two floods in ten years averaging 25 percent). Mobile City Code Sec. 17-2
- Bayou La Batre: the same two tests, and a rolling 10-year count of improvements. Bayou La Batre Ordinance 2020-002
- Dauphin Island: 50 percent, counted over any five years. Dauphin Island FAQ
- Creola: the 25 percent repetitive test as well. Creola Ordinance 2020-003
- Daphne and ADEM: 50 percent of fair market value in the coastal area. Daphne LUDO Sec. 20-6 ADEM Rule 335-8-1-.02(jjj)
Mobile sets building value at the tax assessment, without land, plus 20 percent. It also leaves out landscaping, fences, sheds and other detached structures. Mobile 50 percent packet Mobile 50 percent packet exclusions Ask your office whether a bulkhead counts.
What it means for a bulkhead or boathouse
What does this mean for a bulkhead or boathouse?
Freeboard sets the floor of a house. It does not set the height of a bulkhead, which your engineer designs from soil, waves and water level. The flood zone still shapes your plan in four ways:
- It decides whether a county or city flood permit applies to the job.
- It limits boathouses and sheds below BFE in VE and coastal AE zones.
- It can pull an elevation certificate into a house permit on the same lot.
- It limits insurance: a flood policy from the NFIP skips seawalls, bulkheads, wharves, piers and docks. 44 CFR Part 61, Appendix A(1) It excludes over-water boathouses too. 44 CFR Part 61, Appendix A(1)
Dauphin Island lets a boat house rise no more than 16 feet above the top of the adjacent sea wall. Dauphin Island Ordinance 105
Check your numbers. NOAA gauge thresholds use feet above station datum, not NAVD88. At Coast Guard Sector Mobile, NAVD88 sits 29.16 feet above station zero, and mean higher high water is 1.16 feet above NAVD88. NOAA datums, Coast Guard Sector Mobile Near the Fowl River and Bayou La Batre, mean higher high water is about 0.8 to 0.9 foot above NAVD88. NOAA gauges, Fowl River and Bayou La Batre
The water is rising. Dauphin Island's gauge shows 4.43 millimeters of sea level rise per year since 1966, about 10 inches in 59 years. Mobile County Shoreline Management Plan See the Dog River and Bayou La Batre guides for local flood rules. Read the storm guide and insurance guide next. The glossary defines each term used here.
Show sourcesHide sources
- Mobile County Building Code Adoption and Amendments, Effective July 1, 2026 (Part D and Part E.5)Source reviewed 2026-11-04
- Community Status Book Report: Alabama, Communities Participating in the National Flood Program (report date 10/31/2026)Source reviewed 2026-11-04
- Prelim_NFHL MapServer (layers 1, 3, 21)Source reviewed 2026-11-04
- FEMA National Flood Hazard Layer (NFHL) map serviceSource reviewed 2026-11-04
- FEMA National Flood Hazard Layer, Flood Hazard Zones (layer 28) point queriesSource reviewed 2026-11-04
- FEMA National Flood Hazard Layer, Flood Hazard Zones (layer 28) point queriesSource reviewed 2026-11-04
- High Water Mark Collection for Hurricane Katrina in Alabama, FEMA-1605-DR-AL, Final Report (URS Group for FEMA)Source reviewed 2026-10-31
- Development Permit Application for all properties in V-Zones, A-Zones and X-Shaded (rev. December 2022)Source reviewed 2026-11-04
- Flood Damage Prevention Ordinance, City of Creola, 2020-003Source reviewed 2026-11-04
- Bayou La Batre Ordinance No. 2020-002, Article 4 and definitionsSource reviewed 2026-11-04
- Town of Dauphin Island Zoning Ordinance No. 105, Article 2 definitions (Flood Protection Elevation; Freeboard)Source reviewed 2026-11-04
- Floodplain Management / Flood Zone Information - Baldwin County Building DepartmentSource reviewed 2026-11-01
- Daphne Land Use and Development Ordinance (codified through July 3, 2025)Source reviewed 2026-11-04
- Floodplain Management, City of FairhopeSource reviewed 2026-11-04
- Ordinances of the City of Spanish FortSource reviewed 2026-11-04
- Mobile City Code Chapter 17, Secs. 17-2 and 17-29Source reviewed 2026-11-04
- Land Disturbance (L.D.) Permit GuideSource reviewed 2026-11-04
- Permit Application Checklists | Baldwin County Building DepartmentSource reviewed 2026-10-31
- Baldwin County Building Inspection Department Fee Schedule (effective 10/01/2023, updated 10/01/2024)Source reviewed 2026-10-31
- Mobile County Building Inspections - Information required for obtaining a building permit (7-1-26)Source reviewed 2026-11-04
- Mobile County Storm Water Management Program Plan (December 2017), Appendices D and ESource reviewed 2026-11-04
- Substantial Damage (SD) & Repetitive Loss (RL) Frequently Asked Questions for Property OwnersSource reviewed 2026-11-04
- ADEM Admin. Code Chapter 335-8-1, General Provisions and Review ProcessSource reviewed 2026-11-04
- City of Mobile 50% Flood Packet (rev. May 2020)Source reviewed 2026-11-04
- 44 CFR Part 61, Appendix A(1), Standard Flood Insurance Policy, Dwelling FormSource reviewed 2026-10-31
- CO-OPS station datums, Coast Guard Sector Mobile, AL 8736897Source reviewed 2026-11-04
- NOAA CO-OPS metadata API: station list, datums (1983-2001 epoch) and flood levels for stations 8735523, 8738043, 8739803Source reviewed 2026-11-04
- Mobile County Shoreline Management Plan (December 2025), Section 4.3.1 and Table 12Source reviewed 2026-11-04