Coastal Infrastructure · South Florida

Your seawall is failing and you don't know it.

Cracks. Leaning. Undermining. Most seawalls have never been formally inspected. Repairs cost $1–3K per foot and take months. We use drone photogrammetry and underwater ROV to show you exactly what's vulnerable — before the next hurricane.

Drone + ROV assessment
80%+
Seawalls are private — cities have no inventory
$1–3K
Cost per linear foot to repair (before permitting)
Never
Most seawalls have never been formally assessed
6 mo
Permitting + repair before hurricane season
Also measuring water

The Water Health Score

We fuse bacteria counts, water chemistry, and emerging contaminants into one 0–100 Water Health Score — because seawalls only matter if they're protecting clean water. Explore water quality →

The seawall crisis

The infrastructure nobody prepared for

Most seawalls were built 30–50 years ago. Some are failing now. But cities published climate plans listing seawall upgrades as critical — while owning almost none of them. Property owners see damage and guess on repair decisions. Nobody has a complete inventory.

Cities

No inventory, no plan

Public adaptation strategies say "upgrade aging seawalls" but city officials can't tell you which ones exist, how old they are, or what condition they're in. 80%+ are privately owned.

⚠ No formal assessments
Property owners

See damage, don't know severity

An HOA notices cracks in the seawall. They get a repair quote ($1–3K per foot). Do they repair now or wait? Can they get permits before hurricane season? Will the seawall hold until next year?

⏰ Guess at repair timing
Engineers

Data with no context

County assessor records, property deeds, and scattered inspection reports exist — but no one has pulled them into a usable assessment. It takes weeks of research to even understand a single property's seawall.

📋 Manual, slow research
The data is out there. Cracks in concrete are visible. Undermining leaves traces. Wave exposure is measurable. WaterVue brings these signals together into one assessment — so a property owner or city can make an informed decision before the next storm.
How we assess

Drone + underwater ROV = complete picture

The seawall you see above water is half the story. We use two tools to capture the whole structure — surface damage, geometry, and what's happening below the waterline.

Drone photogrammetry

Overlapping aerial photos are stitched into a 3D model and orthomosaic. We measure surface condition, cracks, geometry, and displacement.

  • Geometry: Height, slope, subsidence, lean
  • Surface: Cracks, spalling, efflorescence, vegetation
  • Displacement: Bulging, rotation, wall-face movement

Underwater ROV inspection

A tethered ROV descends to inspect the submerged face, foundation, and drainage — the hidden critical areas.

  • Submerged face: Cracking, corrosion, scour
  • Foundation: Erosion, undermining, displacement
  • Drainage: Clogging, seepage, weeping holes
Assessment output

You get a roadmap, not a guess

Every assessment becomes a detailed report with a condition score, photographic evidence, prioritized repair recommendations, and resilience metrics for storm surge.

Condition Score (0–100)
  • 0–25: Critical — repair imminent
  • 26–50: Poor — plan repair in 1–2 years
  • 51–75: Fair — monitor, repair in 3–5 years
  • 76–100: Good — maintenance only
Storm surge resilience
  • Current design storm (cat 4–5)
  • Height margin above design
  • Foundation stability
  • Overtopping and seepage risk
Repair prioritization
  • Critical structural defects
  • Surface / drainage issues
  • Cosmetic deterioration
  • Life-cycle cost (repair vs. replace)
Learn more

Common seawall failure modes and storm-readiness timelines

What crack patterns mean. Why undermining spreads. How long repairs actually take. Read expert breakdowns of the seawall crisis in South Florida.

Resource

Crack patterns decoded

Vertical vs. horizontal vs. diagonal cracking — what each tells you about the seawall's structural integrity and urgency.

Timeline

Permitting to completion

How long do repairs actually take? Permitting, contractor schedules, hurricane season cutoffs, and realistic timelines for South Florida.

Case study

A seawall failure walkthrough

What we found at Village Circle Marina: 42-year-old concrete, severe cracking, foundation scour, and the repair window before 2026 hurricane season.

Read all resources →

Know your seawall before the storm.

Get a drone + ROV assessment of your property's seawall, complete with condition score, repair priorities, and storm-surge resilience metrics.

Map your seawall →
Live data sources
Miami Waterkeeperweekly
DOH Healthy Beachesweekly
Miami-Dade DERMmonthly
WaterVue sensorsproposed
Water Health Score
0 · Stressed100 · Healthy
Ring = live swim status (Waterkeeper)
Click a site to open its water profile →
Monitoring Site

Swim status · Waterkeeper
Water Health Score
Water profile

Spokes are colored by source. Faded = no public feed — WaterVue's coverage gap.

Parameters & sources
Coastal Infrastructure

Most seawalls aren't even on the map.

Cities say seawalls are critical. But 80%+ are privately owned, unmapped, and un-inspected. WaterVue locates every seawall, assesses its condition using drone photogrammetry and underwater ROV, and tells you what's vulnerable before the next storm.

Drone assessment: condition, age, material, wave exposure
80%+
Seawalls are privately owned — not inventoried by cities
0
Condition assessments most properties have had
1 storm
Away from sudden failure — no one knows which ones
Drone + ROV
Our assessment method: photogrammetry + underwater scan
The problem

Every coastal city claims seawalls are critical. None know their condition.

Miami, Fort Lauderdale, and their suburbs all list "upgrade aging seawalls" in their climate adaptation plans. Property owners see cracks and slumping, but repairs cost $1–3K per linear foot. And the whole system — which seawalls exist, how old they are, what material, how much wave exposure each face — is scattered across county assessor records, property deeds, and homeowner memories.

The city problem

Plan says upgrade seawalls

Cities publish climate adaptation strategies naming seawall resilience as critical infrastructure. But they don't own most of them — and don't have an inventory of what exists or its condition.

The property owner problem

$1–3K per foot to repair

An HOA or homeowner sees their seawall cracking, slumping, or eroding. A repair quote arrives. They approve or defer — guessing whether failure is years away or imminent.

The WaterVue solution

Survey before the storm

Drone photogrammetry captures the geometry and surface condition. An underwater ROV inspects the structure below the waterline. You get a condition score, a prioritized repair list, and resilience benchmarks.

The data gap is opportunity. Most seawalls in South Florida have never been formally assessed. We map them, measure them, and score them — so a private owner or city can make an informed decision about repair vs. replacement.
How we assess

Drone + underwater ROV = complete picture

The seawall you see above water is half the story. Cracks, settlement, and material degradation happen on both sides. We use two tools to see the whole structure.

Drone photogrammetry

A DJI Phantom or Mavic flies the seawall perimeter and takes overlapping photos from multiple angles. Photogrammetry software stitches them into a 3D model and orthomosaic (pixel-accurate overhead view).

  • Geometry: Height, length, slope irregularities, subsidence
  • Surface: Cracks, spalling, efflorescence (salt staining), vegetation encroachment
  • Horizontal: Lean, rotation, bulging, wall face displacement

Underwater ROV inspection

A small tethered underwater ROV (remotely operated vehicle) descends below the waterline to examine the submerged face, foundation, and drainage system.

  • Submerged face: Cracking, corrosion, scour
  • Foundation: Erosion, undermining, displacement
  • Drainage: Clogging, seepage, weeping holes
Assessment output

From inspection to action

Every assessment becomes a detailed report with a condition score, photographic evidence, prioritized repair recommendations, and resilience metrics for storm surge and sea-level rise.

Condition Score (0–100)
  • 0–25: Critical — repair imminent
  • 26–50: Poor — plan repair in 1–2 years
  • 51–75: Fair — monitor, repair in 3–5 years
  • 76–100: Good — maintenance only
Storm surge resilience
  • Current design storm (cat 4–5)
  • Height margin above design
  • Foundation stability
  • Overtopping and seepage risk
Repair prioritization
  • Critical structural defects
  • Surface / drainage issues
  • Cosmetic deterioration
  • Life-cycle cost (repair vs. replace)

Map your seawall's condition.

Use the WaterVue seawall map to locate vulnerable segments and see condition assessments across the coast — then commission your own property survey.

Explore the map →
Seawall Condition Score
0 · Critical100 · Good
Color: Condition · Thickness: Exposure to storm surge
Click a seawall segment to see its assessment →
Seawall Segment

Condition Score
Storm Surge Risk
Assessment snapshot
Repair priority
Methodology

How the Water Health Score is built

The score is deliberately transparent: every input, its limit, and its source are published so a city manager, an HOA, or a scientist can check the math.

From reading to score

Each parameter is evaluated against an established permissible limit drawn from EPA and APHA guidance and the MTAC core-indicator protocols. A reading inside its ideal band scores 100; the sub-score declines as the value moves past the threshold. Sub-scores are then weighted — core indicators and health-critical contaminants count for more — and averaged into a single 0–100 Water Health Score, translated to an A–F grade.

Where a parameter has no data for a site, it is shown as a gap rather than scored as zero, so sparsely-monitored sites are not unfairly penalized. The score reflects only what is measured, and the map makes the missing pieces explicit.

Parameters & permissible limits

A representative slice of the WaterVue parameter set and the limits each is scored against:

ParameterIdeal / limitFamilySource
Enterococci (bacteria)0–35 good · 70+ unsafe (MPN/100mL)BiologicalWaterkeeper
Dissolved oxygen≥ 5 mg/LCoreDERM
Chlorophyll a25–30 µg/LCoreDERM
Water clarity / turbidity1–5 NTUCoreDERM
Total nitrogen2–6 mg/LCoreDERM
Total phosphorus< 40 ppmCoreDERM
pH6.5–8.5PhysicalDERM
Salinity1 ppt fresh · 35 ppt marinePhysicalDERM
TemperatureUse-dependent (10–20 °C oyster)PhysicalDERM
Heavy metals (mercury)2 µg/LChemicalWaterVue
PFASEmerging — no public feedChemicalWaterVue
MicroplasticsEmerging — no public feedVisual/RemoteWaterVue

Data sources & cadence

Miami Waterkeeper & DOH

Weekly enterococci sampling on the EPA 2012 recreational thresholds (Good 0–35, Moderate 36–69, Poor 70+ MPN). Waterkeeper's numeric results publish to a shared spreadsheet with a machine-readable export; the state's Healthy Beaches program fills official beach sites.

Miami-Dade DERM

A surface-water monitoring program running since 1979 collecting physical and chemical parameters across Biscayne Bay and major canals monthly, served from an ArcGIS map service with a queryable data layer.

WaterVue sensors (proposed)

Real-time Datasonde telemetry plus lab panels close the gaps public programs leave open — PFAS, microplastics, trace metals, and eDNA — on a continuous or monthly basis.

Quality assurance

All monitoring follows standard EPA and APHA protocols: calibrated instruments, certified labs, trained personnel, and periodic audits, consistent with WaterVue's field program for the Himmarshee Canal pilot.

How to read the map

Each site marker carries two data layers at once: the fill color is the Water Health Score, and the outer ring is the current swim status from Waterkeeper's weekly bacteria sampling. In the site panel, the radar's spokes and the parameter rows are colored by source, and faded spokes mark parameters no public program currently measures.

Note on this pilot build: site locations, parameters, sources, and the bacteria thresholds are real. Displayed numeric values are representative pending the live data connection described above.

About

Making water legible

WaterVue maps, measures, and monitors coastal waters so communities can act on real conditions — not outdated assumptions.

Why we exist

In coastal areas, the interconnectedness of ecosystems means a single test can't tell the whole story — when one canal shows signs of pollution, the problem usually extends beyond that site, and traditional monitoring can't map those connections. WaterVue builds an interconnected system of information that maps, measures, and monitors waters in one view, establishing benchmarks based on reality rather than reacting after damage is done.

The Biscayne Bay pilot

The pilot fuses Miami Waterkeeper, DOH Healthy Beaches, and Miami-Dade DERM data across recreation sites, marinas, and canals from Key Biscayne to the Miami River. It runs alongside WaterVue's field work on the Himmarshee Canal — a six-month water-quality monitoring program for the Oyster Institute's BioCarbon restoration trial, establishing the standard protocol we apply everywhere else.

Roadmap

  • NowPilot map, live bacteriaWire Waterkeeper's weekly feed and DERM's monthly chemistry into one score across Biscayne Bay sites.
  • NextSensor spokesDeploy Datasonde telemetry and lab panels to close the PFAS, microplastic, and eDNA gaps.
  • LaterTrend & benchmarksTwelve-month histories per site, restoration impact reports, and predictive advisories.
  • ScaleBeyond the bayExtend the protocol to new watersheds, one monitored site at a time.

Get involved

Sponsor a site

Fund monitoring at a canal, marina, or beach you care about. Sponsorship covers lab supplies, analysis, and staff time — and puts a new site on the public map.

Partner with us

Cities, HOAs, restoration groups, and researchers can commission monitoring and receive baseline data, benchmark reports, and a user-friendly interface.

Explore the pilot map →

Resources

The seawall crisis in South Florida

Expert breakdowns of failure modes, repair timelines, cost analysis, and what's at stake. Because understanding your seawall is the first step to protecting it.

Crack patterns decoded: What your seawall is telling you

Why cracks matter: Cracks aren't just cosmetic — they're the seawall's signal that concrete is under stress, water is infiltrating, and structural failure may follow. The pattern and location of cracks tell you which forces are winning: vertical pressure, lateral soil movement, water pressure, or salt corrosion.

Vertical (tensile) cracks

What they mean: Vertical cracks running top-to-bottom indicate the seawall is being pulled apart — usually by water pressure building up behind it, or by thermal expansion as concrete ages. These cracks allow water to penetrate deeper into the wall, accelerating internal corrosion of rebar.

Storm-readiness impact: High. Vertical cracks are structural concern and allow wave overtopping to seep into the base. Repair timeline: 1–2 years, repair cost per linear foot: $800–1,500.

Horizontal (shear) cracks

What they mean: Horizontal or stepped cracks indicate the seawall is shearing — the upper portion is trying to move differently from the base. This usually means the foundation is settling unevenly or erosion is undermining one section. Horizontal cracks are a sign of foundation failure.

Storm-readiness impact: Critical. Horizontal cracks indicate the seawall is losing structural integrity. A storm surge can cause catastrophic failure. Repair timeline: 6 months to 1 year (urgent), repair cost: $1,200–2,000 per linear foot or replacement.

Diagonal or corner cracks

What they mean: Diagonal cracks emanating from corners or where the seawall meets other structures indicate differential movement — one section of the seawall is moving while another is stuck. Often caused by uneven soil settlement or wave impact concentration.

Storm-readiness impact: Moderate to high. These cracks indicate localized stress and can spread during a storm. Repair timeline: 1–2 years, repair cost: $600–1,200 per linear foot.

Map cracking (hairline network)

What they mean: A dense network of small, interconnected cracks indicates the concrete is experiencing uniform stress across a large area — usually thermal cycling or salt corrosion deep in the concrete. This is often called "crazing" or "map cracking."

Storm-readiness impact: Moderate. While individual cracks are small, the pattern indicates the concrete is weakening uniformly. Sealing is important to prevent water infiltration. Repair timeline: 2–3 years, repair cost: $400–800 per linear foot.

The undermining timeline: How erosion defeats seawalls

Why undermining is the silent killer: Undermining — when water and soil erode the foundation beneath a seawall — is invisible until it's catastrophic. A seawall can look intact while its foundation disappears, leading to sudden failure in a storm.

Stage 1: Initial scour (0–2 years)

Waves and tidal currents begin eroding soil at the base of the seawall. A small void may form at the toe (base) of the seawall, usually only a few inches deep. Visible signs: Sand or soil appearing at the waterline, small holes at the base, or seepage.

Action: This is the best time to intervene — repairs are minimal (adding fill, installing scour protection). Cost: $300–600 per linear foot.

Stage 2: Progressive undermining (2–5 years)

The void grows as more soil erodes. The seawall begins to settle or tilt slightly. Cracks appear at the base or along the wall. The drainage system (weeping holes) may become exposed or clogged. Visible signs: Larger voids, visible tilting, new cracks, water pouring from weeping holes.

Action: Repair is now more complex — requires underpinning (adding support beneath the wall). Cost: $1,000–2,000 per linear foot, timeline: 2–4 months.

Stage 3: Imminent failure (5+ years, untreated)

The void has grown beneath 30%+ of the wall. The seawall is leaning, settling noticeably, or moving sideways. Major cracks are visible. A moderate storm can trigger collapse. Visible signs: Obvious lean, large settlement, major cracks, seepage, exposed rebar.

Action: Repair or replacement is urgent — storm season deadlines become real. Cost: $1,500–3,000+ per linear foot, or $500,000+ for replacement of a large seawall. Timeline: 3–6 months for structural repair (if possible before hurricane season).

Repair or replace? The cost-benefit decision

Repair (good condition score, 60–80)

Cost: $800–1,500 per linear foot. A 300-foot seawall: $240,000–450,000.
Timeline: 2–4 months design + permitting, 2–3 months construction. Total: 4–7 months. Best done in off-season (May–August).
Lifespan: 15–25 years for a good repair on a seawall with solid foundation.

Replacement (poor condition, 20–50)

Cost: $1,500–3,000+ per linear foot (depends on material — steel sheet pile, vinyl, precast concrete). A 300-foot seawall: $450,000–900,000+.
Timeline: 3–6 months permitting + design, 3–4 months construction. Total: 6–10 months. Also best done off-season.
Lifespan: 40–50+ years with modern materials and maintenance.

Rule of thumb: If repair cost exceeds 50% of replacement cost, replacement is usually better. If your seawall is 40+ years old with multiple failure modes, replacement extends your safety margin another generation.

Hurricane-season repair deadlines: Why 6 months matters

South Florida's hurricane season runs June 1 – November 30. Seawall repair permitting and construction almost always stops by May 1 to avoid the season. Here's the timeline:

  • January–February: Assessment window. Get your drone + ROV survey done in calm weather. Condition score guides repair decision.
  • March–April: Permitting. Submit plans to Miami-Dade, Broward, or local authorities. Some counties take 6–8 weeks. If you start in March, you might get approval by late April — just in time for a May start.
  • May–June: Construction begins. Contractors typically work May through mid-August (11 weeks). A moderate 300-foot seawall repair takes 8–10 weeks, leaving a 1-2 week buffer before June 1.
  • June 1 – November 30: Hurricane season. No seawall repairs are permitted or insurable during this window (some counties allow minor work, but structural work stops). If you miss the May deadline, your repair waits until December.
  • December–February: Second repair window (smaller, for work that didn't finish by May).

The implication: If you discover a critical seawall condition (score < 30) in May, you're already missing the current year's repair window. You'll wait until the next January to start. That's up to 8 months of elevated storm risk.

Case study: Village Circle Marina, North Bay Village

The seawall: A 450-foot concrete sheet-pile wall built in 1982, fronting the North Bay Village marina and residential area. Material: 0.375" steel sheet pile with wooden cap, age 42 years.

Condition: Severe. Score: 35 (critical). Multiple vertical cracks (some 0.25" wide), horizontal cracking at the 4-foot elevation (indicating shear), exposed rebar on the south end, efflorescence (salt staining), and visible undermining with a 2-foot void at the base of the south section. The wall is leaning slightly toward the water.

The risk: A Category 4 hurricane storm surge (8–12 feet above mean high water) would likely overtop the wall and potentially cause collapse of the compromised south section. Residents and property in the area would face immediate flooding and structural damage.

Repair options and costs:

  • Option 1: Structural repair + underpinning. Add underpinning beneath the south section ($400K), seal and inject cracks ($80K), replace the wood cap with precast concrete ($150K). Total: ~$630K. Timeline: 4 months. Extends seawall life 15–20 years. Decision: Viable if residents are willing to share cost through HOA special assessment.
  • Option 2: Full replacement. Replace entire 450-foot wall with modern sheet pile or vinyl bulkhead (~$675–1,350K depending on material). Timeline: 5–6 months. Extends life 40–50 years, improves storm resilience (design for higher surge risk). Decision: Better long-term investment, but requires financing or city/county partnership.
  • Option 3: Do nothing. Continue to monitor. Risk: High. Next major hurricane could cause failure and flooding of $50M+ in waterfront property. Liability for HOA and property owners increases.

Recommendation: Option 2 (full replacement) is the most prudent despite higher upfront cost. The seawall is 42 years old and showing multiple failure modes; a repair would extend life only 15–20 years, at which point another costly repair would be needed. A replacement gets another 40–50 years and improves resilience to future climate scenarios (higher storm surge, sea-level rise).

Timeline to repair/replace: June 2025 assessment → July–August 2025 permitting → December 2025 – April 2026 construction → May 2026 completion before hurricane season. If delayed to 2027, the wall operates another full hurricane season at elevated risk.

How to prepare: A DIY seawall inspection checklist

Before you commission a full drone + ROV survey, do a visual walkthrough of your seawall. Look for these signs:

  • Visible cracks (any width) on the face or top of the wall
  • Leaning or tilting (step back, sight along the top edge)
  • Settlement or subsidence (sunken areas along the top)
  • Efflorescence (white salt staining on the face)
  • Exposed rebar or aggregate
  • Vegetation growing on or inside cracks
  • Seeping or flowing water from weeping holes
  • Voids or holes at the base (underwater, only visible at low tide)
  • Chunks of concrete spalling off or lying at the base
  • Age (check county records or HOA history — if > 40 years, priority for assessment)

If you check 3+ boxes, contact a structural engineer or commission a WaterVue assessment. If you check 6+, your seawall needs urgent attention — plan repair/replacement in the next 12–18 months.