In short
- Type in your cap height (feet, NAVD88) and see it next to six water levels from our NOAA page.
- It shows the gap in feet, above or below each level. It does not predict anything.
- Your engineer and the City set the real cap height. This is a planning check only.
This seawall cap height calculator for Cape Coral compares the top of your wall with real water levels recorded at NOAA's Fort Myers tide gauge. You enter one number, your cap elevation. We show how far it sits above or below the average high tide, three NOAA flood levels and the two storm peaks on our sea level and tides page. We are an independent referral service that connects visitors with independent local contractors, not a contractor or an engineer.
The six gauge levels the tool uses
Every level comes from the NOAA gauge page on this site. Heights are in feet against NAVD88, the national survey reference. The flood levels are NOAA's heights above average high tide (+0.28 ft NAVD88); adding them is our arithmetic.
| Level | Ft NAVD88 | What it is |
|---|---|---|
| Avg high | 0.28 | Average daily higher high tide (MHHW) |
| Minor | 1.97 | NOAA minor flood level (1.69 ft above MHHW) |
| Moderate | 2.94 | NOAA moderate flood level (2.66 ft above) |
| Major | 4.17 | NOAA major flood level (3.89 ft above) |
| Oct 2024 | 5.53 | Highest monthly reading that month (matches Hurricane Milton) |
| Sep 2022 | 7.52 | Highest in the record (matches Hurricane Ian) |
What the result tells you
- Where your cap sits against levels measured at one river gauge.
- Which recorded events reached above it.
- A good list of questions for your engineer.
What it cannot tell you
- Water levels in your own canal.
- The right cap height. Your engineer and the City permit review set that.
- Future water levels. We make no forecast.
Do not design from this. The gauge is on the Caloosahatchee River at Fort Myers, not in your canal. Storm peaks are one-off events and a wall is not built to a gauge reading. This is a planning check, not engineering or flood-insurance advice.
Questions to take to your engineer and contractor
- What cap elevation is on the plans? Ask for it in feet NAVD88, in writing, and who set it.
- Which water levels did the design assume? Ask about your canal, not the river gauge.
- Is the cap height changing? A taller cap can affect neighbor tie-ins; see seawall returns and neighbor tie-ins.
- What does the permit require? See the permit guide and the design standards guide.
- Is the cost itemized? Run your length through the seawall cost calculator, then compare written bids in the bid comparison calculator.
Next step: get real quotes
Use the request form on this page to be connected with licensed local marine contractors, and read how to choose a seawall contractor before you sign.
En español: calculadora de altura de tapa de muro de contención.
Frequently asked questions
Where do the calculator's water levels come from?
From the NOAA Fort Myers gauge figures already published on our sea level and tides page: average high tide, NOAA's three flood levels and the September 2022 and October 2024 peaks. We added nothing else.
What is NAVD88?
The national survey height reference. Surveys and elevation certificates commonly use it. If your paperwork uses another reference, ask the surveyor to convert the cap height to NAVD88 before using this tool.
Does this tell me how high my cap should be?
No. Your engineer's design and the City's permit review set the cap elevation for your site. This tool only shows where a number sits against recorded water levels.
Does the tool predict future water levels?
No. It uses recorded levels only and makes no forecast.
Is the Fort Myers gauge the same as my canal?
No. It sits on the Caloosahatchee River at Fort Myers. A canal can rise and fall differently, so treat the comparison as a regional guide.