Planning a Seawall Replacement

A seawall replacement brings together engineering, regulation, construction and neighbors, often on a tight piece of shoreline. Owners who move through it smoothly tend to do three things well: they collect the right documents early, they make the major decisions before design is finished, and they treat permit review as a phase to plan for rather than a formality.

This guide is the planning companion to our articles on seawall replacement design issues and the bulkhead replacement construction sequence. Use it as a checklist, and adapt it to your site and jurisdiction.

The project at a glance

The table below lays out a typical sequence. It does not assign fixed durations, because they vary widely with site conditions, the agencies involved and contractor availability. The right-hand column shows what tends to stretch each phase.

On federal timing, the 2026 Nationwide Permits state that, with listed exceptions, an applicant who submits a complete pre-construction notification may generally proceed if the district does not respond within 45 days. Not every project needs one, and state and local reviews run on their own schedules.

Documents to gather

As an example of local requirements, the City of Margate, Florida's standard canal wall detail requires a boundary survey by a licensed surveyor dated within one year of the permit application.

Decision points to settle early

1. Repair, replace or alternative. The Virginia Institute of Marine Science suggests weighing shoreline condition, structural integrity and remaining life expectancy, and seeking expert advice. See bulkhead repair vs. replacement.
2. Wall type. Material, cantilever or anchored design, and whether a sloped or nature-based option suits the site. See our materials guides.
3. Alignment. Same line, slightly waterward where allowed, or landward. Regulators often decide this, so ask early.
4. Top elevation. Local minimums, such as Fort Lauderdale's 5-foot standard for new seawalls, and projected water levels, which NOAA's Sea Level Rise Viewer can help visualize for planning purposes.
5. Access. Land-based or water-based equipment. Maryland's replacement form asks applicants which they will use.
6. Neighbor transitions. How the new wall meets adjacent walls at each property line.
7. Budget and contingency. A realistic allowance for unknowns below ground and in the water. Our budget planner can help frame the range.

Questions for your engineer

• What is causing the current problems, and how confident are you in that diagnosis?
• What design life is the new wall intended for, and what water levels does it assume?
• What top elevation are you proposing, relative to which datum, and why?
• Is soil information needed, and what happens to the design if conditions differ?
• How will the ends and the joints with neighboring walls be detailed?
• Which permits do you expect, and what information will each agency need?
• Will you visit during construction and provide closeout certification?

Questions for your contractor

• Have you built this wall type, at this scale, in this jurisdiction?
• Will you work from land, water or both, and what will be disturbed?
• How do you handle unexpected obstructions, such as buried debris or old anchors?
• Who obtains permits, and who is responsible for meeting their conditions?
• What is included in the price, and what is excluded or priced as an allowance?
• What warranty do you provide, and what does it cover?
• How will the site be restored when work is finished?

North Carolina's state handbook offers a useful caution: contractors tend to specialize in one stabilization type and may recommend that method by default. Getting independent input on the approach, and bids on the same scope, helps. See how to hire a marine contractor and how to compare contractor quotes.

Permits and authorities

The same handbook notes that, depending on scope and location, an owner or their representative may need to interact with as few as one or as many as 14 federal and state agencies. Local approvals come on top of those. Maryland's notification form states that a local government approval is required in addition to federal or state authorization, and that authorizations must be in place before any work begins, including site preparation and stockpiling of materials. Start with the permit navigator and the bulkhead permit guide.

Closeout and aftercare

Closeout is easy to rush and expensive to skip. Margate's standard detail, for example, requires an as-built survey or engineer of record certification confirming the wall was built as permitted before the engineering permit is closed. Keep final drawings, permits, inspection approvals, warranty terms and photos together. They help with future maintenance, insurance questions and resale. A simple annual inspection, using our maintenance checklist, keeps a new wall on track.

When you are ready to share your project with contractors, the project brief tool organizes the details above into a single summary.