What should you check after a hurricane damages your bulkhead?
Document the damage, then call the permit office before you repair.
- Stay off ground that may be undermined. Photograph the wall, cap and yard from a safe distance.
- Look for sinkholes behind the wall, shifted caps, bowed panels and exposed tie rods.
- Check the toe at low water, especially after a blowout.
- Have a marine engineer inspect before you patch anything.
- Call your local permit office before repairs. Use the permit map.
Mind the clocks. Nationwide Permit 3 can cover a storm-damaged wall when repairs begin, or are under contract, inside two years. 2026 Nationwide Permits An ADEM emergency approval is good for 120 days at most. ADEM coastal rules
The Corps emergency permit, ALGP-15, can be granted on first contact. The owner files a notice within 60 days after finishing. 2026 Alabama General Permits Check what your policies say about the wall in the insurance guide. For the repair-or-replace choice, use the repair or replace guide.
Which tide gauge fits which Mobile Bay shore?
What does Mobile Bay storm history say about your shore?
Storm water does not rise evenly around the bay. Pick the gauge nearest your wall and read its numbers, not the bay-wide headline.
| Shore | Gauge and station ID |
|---|---|
Mobile bay front, Arlington, Brookley | Coast Guard Sector Mobile, 8736897 |
Downtown Mobile River edge | Mobile State Docks, 8737048 |
Dog River, Halls Mill, Rabbit Creek | Dog River Bridge, 8735391 |
Chickasaw Creek and the upper river | Chickasaw Creek, 8737138 |
Fowl River and Mon Louis Island | West Fowl 8738043; East Fowl 8735523 |
Bayou La Batre, Coden, Cedar Point | Bayou La Batre Bridge, 8739803 |
Dauphin Island | Dauphin Island, 8735180 |
Sources: NOAA CO-OPS station metadata; Chickasaw Creek gauge.
The Eastern Shore has no working gauge. NOAA lists its Baldwin County sites only as tide predictions, and the Weeks Bay gauge came out in April 2022. NOAA station list NOAA Weeks Bay record Use Dog River, Coast Guard Sector and Dauphin Island as rough guides.
Most readings below are in feet above mean higher high water, or MHHW (the average of the higher daily high tides). At the Coast Guard Sector gauge, MHHW is 1.16 feet above NAVD88 (the survey datum on elevation certificates). NOAA datums
How high did Katrina push water at Mobile State Docks?
The State Docks gauge read 11.45 feet on August 29, 2005, close to the 11.60-foot record from July 5, 1916. That reading is in feet above mean sea level. NWS Mobile Katrina page
- Bayou La Batre saw surge of 12 to 14 feet, and many homes were engulfed. NWS Mobile Katrina page
- Dauphin Island read 6.63 feet, and its west end went completely under water. NWS Mobile Katrina page NWS Mobile Katrina page
- FEMA's survey of high-water marks found levels above 13 feet NAVD88 just north of Fairhope, where a bluff held the surge back from the land. FEMA high-water-mark study
What did Frederic, Georges and Ivan show?
Frederic made landfall on Dauphin Island as a Category 4 storm on September 12, 1979. Surge was 8 to 10 feet in northern Mobile Bay. NWS Mobile Frederic page A high-water mark on Dauphin Island, 7.95 feet above MHHW, is still the highest on record there. NOAA CO-OPS
Georges in 1998 beat Frederic at the State Docks, at 8.94 feet above mean sea level against 8.05 feet. Bayou La Batre read 8.80 feet. NWS Mobile Georges page
Georges came ashore to the west and Ivan to the east, and the gauges show it. Bayou La Batre's middle gage hit 8.27 feet in Georges but 4.66 in Ivan. Cedar Point on Mobile Bay went the other way, 6.90 in Ivan and 5.60 in Georges. NWS Mobile Ivan page
Why did Zeta hit Bayou La Batre harder than Dauphin Island?
Zeta in October 2020 is the best lesson in gauge choice. It produced the readings below, all in feet above MHHW.
| Gauge | Peak above MHHW |
|---|---|
Bayou La Batre Bridge | 6.89 ft |
West Fowl River Bridge | 5.92 ft |
Coast Guard Sector Mobile | 5.32 ft |
Mobile State Docks | 5.16 ft |
Chickasaw Creek | 4.52 ft |
Dog River Bridge | 4.38 ft |
East Fowl River Bridge | 3.68 ft |
Dauphin Island | 2.42 ft |
Sources: NWS Mobile gauge table.
Surveyed water marks reached 7 to 9 feet near Bayou La Batre and Coden. NWS Mobile Zeta page On the Eastern Shore, a survey team measured 7 to 9 feet from the Causeway south to Fairhope. NHC Zeta report
Piers and seawalls paid for it. See the Bayou La Batre guide and the Point Clear guide. Several Eastern Shore piers were destroyed and the seawall at the Fairhope Pier was damaged. NHC Zeta report The Grand Hotel pier at Point Clear was destroyed. WKRG report
What did Sally's blowout do on Dog River?
Sally came ashore east of the bay in September 2020, so Mobile's west shore saw little surge. The highest Sally reading at Dog River Bridge was only 1.99 feet above MHHW. NOAA CO-OPS data
Then north winds drained the bay. Dog River Bridge fell to 5.58 feet below MHHW, and the Coast Guard Sector gauge to 8.69 feet below. NOAA CO-OPS data NHC says nearly every gauge around the bay fell below its lowest normal tide. NHC Sally report
A blowout bares the base of a wall. Check for scour, exposed toes and loose rock when the water returns. The Dog River guide covers that shore. Dauphin Island saw the opposite: a 3- to 4-foot surge on its north side wrecked docks and piers, including the Dauphin Island Marina. NWS Mobile Sally page
What about Nate, Ida and Isaias?
- Nate (October 2017): Coast Guard Sector hit 5.34 feet above MHHW and Dog River 4.60. Baldwin County counted nearly 200 damaged piers, 62 of them with major damage. NOAA CO-OPS data NOAA CO-OPS data NWS Mobile Nate report
- Ida (August 2021): Bayou La Batre peaked at 3.82 feet. Three miles of Bienville Boulevard on Dauphin Island were under up to 4 feet of sand. NWS Mobile Ida page
- Isaias (October 2026): north winds again pushed water out of the upper bay, to 3.22 feet below MHHW at the State Docks. NWS Mobile Isaias report
NWS flood steps at four bay gauges are 2.0, 3.0 and 6.0 feet above MHHW for minor, moderate and major. Zeta and Nate topped the moderate step everywhere, and only Bayou La Batre in Zeta topped the major step. NOAA CO-OPS flood levels
Hurricanes are not rare here. MBNEP says Mobile Bay can expect a hurricane landfall about every 10 years and a major one about every 28. MBNEP Eastern Shore plan
Why do rain and surge together matter?
A wall can be hit by water from two sides at once. Isaac in 2012 pushed storm tides of 4 to 6 feet into Mobile Bay while 9.71 inches of rain fell at Mobile. Peaks were 3.84 feet of surge at the State Docks, 3.97 at Bayou La Batre and 3.64 at Dog River. NWS Mobile Isaac page
Gustav in 2008 did the same. Rain of 6 to 9 inches could not drain because of the high tides, and 53 Bayou Sara residents in Saraland were evacuated. The surge also destroyed the $4 million berm on the west end of Dauphin Island. NWS Mobile Gustav page
Elena in 1985 shows the island split. Surge was 8.4 feet on Dauphin Island's Gulf side but 3.5 feet on its bay side. NWS Mobile Elena page
What are the substantial-damage rules by city?
Flood ordinances are written for buildings. Ask your floodplain administrator whether a wall counts. These are the thresholds on record.
| Jurisdiction | Rule |
|---|---|
City of Mobile | 50% of market value, or two floods in 10 years averaging 25% |
Bayou La Batre | 50%, or two floods in 10 years averaging 25% |
Dauphin Island | 50%, added up over any 5-year period |
Daphne coastal area | 50% of fair market value |
Creola | 50%, or two floods in 10 years averaging 25% |
ADEM coastal rules | 50% of fair market value |
State Lands | More than 50% of the structure |
Sources: Mobile City Code; Bayou La Batre ordinance; Dauphin Island FAQ; Daphne ordinance; Creola ordinance; ADEM definitions; State Lands rule.
Mobile estimates a building's value as its assessed value without land, plus 20 percent. Mobile 50% flood packet No rule was confirmed for unincorporated Mobile County, Spanish Fort, Fairhope or Baldwin County, so ask each office. The flood zone guide explains elevation terms.
Show sourcesHide sources
- 2026 Nationwide Permit 3, Maintenance, 91 FR 768Source reviewed 2026-10-31
- ADEM Admin. Code Chapter 335-8-1, rule 335-8-1-.07 General ConditionsSource reviewed 2026-11-04
- ALGP-15 Emergency Permit (SAM-2025-00974-LHL), 2026 Alabama General Permit ProgramSource reviewed 2026-10-31
- CO-OPS Metadata API, station records for Mobile Bay gaugesSource reviewed 2026-11-04
- CO-OPS Metadata and Data APIs: Chickasaw Creek 8737138Source reviewed 2026-11-04
- CO-OPS Metadata API: water level stationsSource reviewed 2026-10-31
- CO-OPS station metadata: 8732828 Weeks Bay, Mobile Bay, ALSource reviewed 2026-10-31
- CO-OPS station datums, Coast Guard Sector Mobile, AL 8736897Source reviewed 2026-11-04
- NWS Mobile: Hurricane Katrina storm surge and impactsSource 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
- Hurricane Frederic - September 12, 1979Source reviewed 2026-11-04
- CO-OPS Top Ten Water Levels: 8735180 Dauphin Island, ALSource reviewed 2026-10-31
- NWS Mobile: Hurricane GeorgesSource reviewed 2026-11-04
- Hurricane Ivan - September 16, 2004 (Table 3, observed storm surge, courtesy USACE Mobile District)Source reviewed 2026-11-04
- NWS Mobile Hurricane Zeta and Hurricane Sally event pages (maximum observed water level tables)Source reviewed 2026-11-04
- National Hurricane Center Tropical Cyclone Report: Hurricane Zeta, 24-29 October 2020Source reviewed 2026-11-04
- Iconic pier destroyed, Eastern Shore residents survive ZetaSource reviewed 2026-11-04
- CO-OPS Data API, water_level, Dog River Bridge, Chickasaw Creek and Coast Guard Sector Mobile (September 15-17, 2020)Source reviewed 2026-11-04
- National Hurricane Center Tropical Cyclone Report: Hurricane Sally, 11-17 September 2020Source reviewed 2026-11-01
- NWS Mobile: Hurricane SallySource reviewed 2026-11-04
- CO-OPS Metadata and Data APIs: Coast Guard Sector Mobile 8736897Source reviewed 2026-11-04
- CO-OPS Data API, water_level, Dog River Bridge 8735391 (queried for Zeta, Nate and Francine windows)Source reviewed 2026-11-04
- NWS Mobile: Hurricane NateSource reviewed 2026-11-04
- NWS Mobile: Hurricane Ida (August 2021)Source reviewed 2026-11-04
- County Impacts Associated with Hurricane Isaias (2026)Source reviewed 2026-10-31
- CO-OPS flood levels API, Dog River, Fowl River, Bayou La Batre and Coast Guard Sector gaugesSource reviewed 2026-11-04
- Eastern Shore Watershed Management Plan (final, Aug. 16, 2023)Source reviewed 2026-11-04
- NWS Mobile: Hurricane IsaacSource reviewed 2026-11-04
- NWS Mobile: Hurricane GustavSource reviewed 2026-11-04
- NWS Mobile: Hurricane Elena (September 1985)Source reviewed 2026-11-04
- Mobile City Code Chapter 17, Stormwater Management and Flood Control, Sec. 17-2Source reviewed 2026-11-04
- Bayou La Batre Ordinance No. 2020-002, definitions; Floodplain Development Permit formSource reviewed 2026-11-04
- Substantial Damage (SD) & Repetitive Loss (RL) Frequently Asked Questions for Property OwnersSource reviewed 2026-11-04
- Daphne Land Use and Development Ordinance (codified through July 3, 2025)Source reviewed 2026-11-04
- Flood Damage Prevention Ordinance, City of Creola, 2020-003, DefinitionsSource reviewed 2026-11-04
- ADCNR Admin. Code r. 220-4-.09 Placement and Configuration of Piers and Other Improvements on State Owned Submerged LandsSource reviewed 2026-10-31
- City of Mobile 50% Flood Packet (rev. May 2020)Source reviewed 2026-11-04