Seawall and bulkhead terms, explained.
What your bid and permit mean.

What are the parts of a seawall or bulkhead called?

• Bulkhead: an upright wall that holds soil back from the water. It is the usual Alabama word. Orange Beach Zoning Ordinance Art. 2 See seawall replacement.
• Seawall: the same kind of wall, often taller or built where waves are stronger. Many local rules list both words together. Orange Beach Code Sec. 30-184(6)
• Revetment: a sloped facing of stone or concrete on a bank, not an upright wall. Orange Beach Zoning Ordinance Art. 2
• Riprap: loose stone piled on a slope to stop wave and current erosion. See riprap and shoreline stabilization.
• Living shoreline: marsh plants, oyster shell or low rock that hold the edge instead of a wall. See living shorelines.
• Cap: the concrete or wood beam along the top of the wall. It ties the panels together and gives you a walking edge. See cap and panel repair.
• Panel: one section of the wall face. Panels may be vinyl, concrete, steel, aluminum or wood boards. See bulkhead materials.
• Sheet pile: a long interlocking panel driven into the bottom to form the wall face. Orange Beach has permitted vinyl sheet pile in 16-foot lengths. Orange Beach permit ST26-000035
• Piling: a post driven deep into the ground for support. Front pilings sit in the water. Landside pilings anchor the wall from behind. Orange Beach permit ST21-000353
• Wale (whaler): a horizontal beam that runs along the wall and spreads load across the panels. A 2026 permit lists double 2x8 marine-grade whalers. Orange Beach permit ST26-000035
• Tie rod: a steel rod that links the wall to an anchor behind it. One permit replaced old rods with 5/8-inch stainless rod. Orange Beach permit ST26-000131 See tiebacks and anchors.
• Deadman: a buried anchor, often a piling or beam, that the tie rod hooks to. Permit papers call these landside deadman pilings. Orange Beach permit ST21-000353
• Toe: the bottom edge of the wall or slope where it meets the bed. Scour at the toe can undercut a wall. See seawall assessment.
• Backfill: the soil and stone placed behind a new wall. Soil loss here is a common sign of trouble. See soil loss and drainage.
• Weep hole: a small opening that lets ground water drain through the wall so pressure does not build. Orange Beach lists drainage with weepholes among its review criteria. Orange Beach Zoning Ordinance Sec. 10.0305(k)
• Filter fabric: a cloth layer behind the wall that lets water out but keeps soil in. Orange Beach asks for a porous filter with weepholes. Orange Beach Zoning Ordinance Sec. 10.0305(k)
• Return wall (wing wall): a short wall that turns back into the land at each end. It stops water from flanking the main wall. Orange Beach Zoning Ordinance Sec. 10.0305(k)

A good bid names the panel material, rod size, anchor type and cap by name.

What do the water and survey terms mean?

• Mean high water (MHW): the average height of all high tides. Federal Form 166 drawings must show it. ADEM Form 166 drawings
• Mean high tide line: the same idea as it appears in Alabama rules. Land waterward of it under tidal water is state-owned submerged land. State Lands rule 220-4-.09(3)(p)
• MHHW: mean higher high water, the average of the higher of the two daily high tides. At Dauphin Island it is about 0.7 feet above NAVD88. NOAA station 8735180 datums
• MLLW: mean lower low water, the average of the lower daily low tide. At Weeks Bay the range from MLLW to MHHW was 1.61 feet. NOAA station 8732828
• Tidal datum: a fixed reference level, such as MLLW, used to measure water height. Gauge numbers only make sense with their datum. NOAA station 8737048 datums
• NAVD88: the 1988 North American Vertical Datum, the land-elevation zero. Orange Beach site plans must use it. Orange Beach submittal checklist
• Boundary survey: a map by a licensed Alabama surveyor that shows lot lines, flood zones and often the water line. Orange Beach submittal checklist
• Fetch: the open-water distance wind blows across to build waves. Long fetch means bigger waves. 2026 NWP 13 note
• Storm surge: the wall of water a storm pushes onto land above the normal tide. Hurricane Frederic raised 12 to 15 feet on the Gulf beaches. NWS Mobile, Frederic See storms and seawalls.
• Special Flood Hazard Area (SFHA): land FEMA maps show as having a flood risk, such as zones A, AE and VE. Baldwin County needs a flood permit for marine work there. Baldwin County checklist
• Flood zone AE: a mapped flood area with a base flood elevation, mostly inland from breaking waves. Baldwin County maps include AE zones. FEMA flood layer, Baldwin County
• Flood zone VE: a coastal high-hazard zone where waves can be large. Baldwin County VE zones carry base flood elevations of 10 to 18 feet. FEMA flood layer, Baldwin County
• Coastal A zone: an A zone near the coast where waves can still do damage. Orange Beach holds it to the same three-feet-above-BFE rule as VE. Orange Beach Ord. 2024-1472
• Base flood elevation (BFE): the height floodwater is expected to reach in a flood with a 1 percent yearly chance. Orange Beach requires floors two feet above it. Orange Beach Ord. 2024-1472

The flood terms matter for insurance and for any house rebuild. See the seawall insurance guide and seawall height requirements.

What do the permit and agency terms mean?

• ADEM: the Alabama Department of Environmental Management. It runs the Coastal Program and reviews shoreline armoring. Orange Beach contracts with it for coastal permits. Orange Beach Zoning Ordinance Art. 9
• Coastal Area: land below the 10-foot contour and out three miles from mean high tide. Construction there needs ADEM review. Orange Beach Zoning Ordinance Art. 9
• Coastal Construction Line (CCL): a mapped line along the Gulf beach set by state coordinates. New structures between it and the water are tightly limited. ADEM rule 335-8-1-.02(p) See Gulf-front armoring.
• Gulf-front armoring: a wall, bulkhead or riprap on the Gulf beach or dunes. It is barred unless landward of the CCL and needed to protect a structure. ADEM rule 335-8-2-.08(4)
• State Lands: the Alabama State Lands Division, part of the Department of Conservation and Natural Resources. It manages state-owned water bottoms. State Lands rule 220-4-.09(3)(p)
• RTI: the Request to Impact State Owned Submerged Lands, a $100 application for a Consent of Use, easement or dredge permit. State Lands rule 220-4-.09(4)(e)
• Consent of Use: State Lands permission, in place of a paid easement, for small projects. It can cover replacing a bulkhead within two feet waterward of mean high tide. State Lands rule 220-4-.09(4)(e)2(iv)
• Riparian rights: the rights of a waterfront owner to use the water edge, such as a dock. Alabama's coastal rules list exercising them as a permissible use. Code of Alabama 9-7-13(a)
• Corps of Engineers: the U.S. Army Corps of Engineers, Mobile District, which reviews work in waters of the United States. ADEM Form 166
• Nationwide Permit 13 (NWP 13): the Corps permit for bank stabilization such as bulkheads and riprap, with length and material limits. 2026 NWP 13
• Nationwide Permit 54 (NWP 54): the Corps permit for living shorelines on low to mid-energy shores. 2026 NWP 54
• Nationwide Permit 3 (NWP 3): the Corps permit for repairing or replacing a serviceable structure that was already authorized. 2026 NWP 3
• Joint application (Form 166): the one form that goes to the Corps, with copies to ADEM and State Lands. ADEM Form 166
• Building permit: the city or county permit to build. Orange Beach charges $50 for a bulkhead on a one- or two-family home. Orange Beach fee schedule
• Marine Accessory permit: Baldwin County's flood permit for docks, piers and bulkheads in a flood zone, at $75. Baldwin County fee schedule
• Substantial improvement: repair or rebuilding that costs 50 percent or more of a structure's value, which ADEM treats as a substantial improvement. ADEM rule 335-8-1-.02(jjj)

See the permit guide for who to call first in each city.

What do the money and contract terms mean?

• Licensed contractor: in Alabama, anyone paid to do residential work over $10,000 needs a Home Builders Licensure Board license. Code of Alabama 34-14A-2(16) See how to verify a contractor.
• Home Builders Licensure Board: the state board that licenses residential builders. The written contract must show the license number. Code of Alabama 34-14A-7(f)
• Owner exemption: a way for owners to act as their own contractor. Baldwin County makes you file a sworn statement before the permit. Baldwin County owner exemption
• Lien: a legal claim on your property by someone who did work or supplied materials and was not paid. Code of Alabama 35-11-210
• Lien deadline: an original contractor has six months from the last work to file a lien. Code of Alabama 35-11-215
• Bid: a contractor's written price for a defined scope of work. Compare bids only when the scope matches. See seawall costs.
• Bid tabulation: a table of every bid on a public job, line by line. Baldwin County posts them, such as six vinyl wall bids at Lillian in 2022. Lillian bid tabulation
• Declared valuation: the job value an applicant writes on a permit. It is not an invoice. Orange Beach permit ST26-000145
• Change order: a written change to the contract price or scope after signing. Get each one in writing before the work starts.
• CRS discount: a flood insurance discount for communities that go beyond minimum rules. Orange Beach is Class 6, a 20 percent discount. FEMA CRS list
• NFIP: the National Flood Insurance Program. Its standard policy does not insure seawalls or bulkheads. 44 CFR Part 61 Appendix A(1)

For a condo or HOA wall, see HOA seawall repair.

Seawall term questions

Are mean high water and mean high tide the same line?

They describe the same idea, the average high-tide height. Federal Form 166 says mean high water. ADEM Form 166 drawings Alabama State Lands says mean high tide. State Lands rule 220-4-.09(3)(p) Ask your surveyor to mark the line each agency wants.

Who owns the water bottom in front of my wall?

Alabama owns tidal land waterward of the mean high tide line, unless it was conveyed. State Lands rule 220-4-.09(3)(p) That is why State Lands reviews work there.

What is the difference between a building permit and Form 166?

The building permit comes from your city or county. Form 166 goes to the Corps with copies to ADEM and State Lands. ADEM Form 166 Many bulkheads need both.

Do I need a licensed contractor for bulkhead work?

Usually yes. Residential work over $10,000 needs a Home Builders Licensure Board license. Code of Alabama 34-14A-2(16) An owner may claim an exemption, with conditions. Baldwin County owner exemption