Seastead Location Analysis – Anguilla & International Waters

Search Criteria

Sandy bottom for mooring-screw anchors
Water depth ≤ 100 feet (30 m) – current installation limit
Out of sight from main Anguilla island residents (preferred)
Reasonable wave climate for a single-family TLP
International waters target: > 200 NM from any country's baseline, within 2,000 NM of Anguilla

Part A – Anguilla Territorial Sea & EEZ Sites

These locations are within Anguilla's jurisdiction. They are screened so that the seastead would not be visible from the main island's populated north and south shores. The key trick is to place behind (leeward/far side of) outlying cays or far enough east to be below the horizon.

A-1 – East (Lee) Side of Scrub Island

Centre (approx.)	18.468°N, 62.966°W
Bearing / Distance from Anguilla Main	ENE ~7 NM from Island Harbour
Why hidden	Scrub Island (elevation ~40 ft) blocks the line-of-sight from The Valley, Sandy Ground, and most of the south shore. Placing on the east or southeast side of Scrub means the island itself screens the seastead.
Depth	30–80 ft (10–25 m) on the sand shelf extending SE of Scrub
Seabed	Sand and coral rubble patches; good sandy areas southeast of the island Sandy
Usable area (≤100 ft, sand)	~0.5 × 0.3 NM (~3,000 × 1,800 ft)
Capacity @ 500 ft grid	~18–21 seasteads
Wave Climate	Sheltered Scrub blocks prevailing east trade-wind swell on the west side; the east side is more exposed. Southeast pocket: Significant wave height (Hs) typically 0.5–1.2 m in trades, but 2–4 m in northern swells (winter) or tropical storms.
Notes	Closest viable site to the main island. A short 20-minute boat ride from Island Harbour. Easy logistics.

A-2 – South Side of Dog Island

Centre (approx.)	18.271°N, 63.250°W
Bearing / Distance from Anguilla Main	WNW ~9 NM from Road Bay / Sandy Ground
Why hidden	Dog Island (peak ~50 ft) lies NW of the main island. Placing on the southwest side puts Dog Island between the seastead and all main-island residences. No populated vantage point on Anguilla has a line-of-sight.
Depth	25–70 ft (8–21 m) on the sandy shelf south of Dog Island
Seabed	Predominantly sand with grass patches Sandy
Usable area (≤100 ft, sand)	~0.6 × 0.4 NM (~3,600 × 2,400 ft)
Capacity @ 500 ft grid	~28–35 seasteads
Wave Climate	Sheltered from N swell Open to SW swell Dog Island shelters from winter north swells. Trades wrap around, Hs typically 0.6–1.3 m; occasional summer S/SW swell can raise to 1.5–2.5 m.
Notes	Dog Island is uninhabited. Nice for privacy. Somewhat longer boat run. Excellent fishing grounds nearby.

A-3 – Prickly Pear / Seal Island Reef – North Side

Centre (approx.)	18.295°N, 63.175°W
Bearing / Distance from Anguilla Main	NW ~5 NM from Road Bay
Why hidden	Placed on the north side of Prickly Pear Cays and Seal Island Reef. The reef system and cays block view from Anguilla's north shore. However, some hilltop residences may still glimpse the site — careful sightline survey recommended.
Depth	20–60 ft (6–18 m) on sand patches north of the reef
Seabed	Mixed sand and coral rubble; must pick sandy windows Sand patches
Usable area (≤100 ft, sand)	~0.3 × 0.3 NM (~1,800 × 1,800 ft)
Capacity @ 500 ft grid	~9–12 seasteads
Wave Climate	Moderate Open to north swells; Hs 0.5–1.0 m in calm trades, 2–3 m in winter north swell events.
Notes	Closest to Sandy Ground / Blowing Point but visibility-screening is the weakest here. Best used only if sightline study confirms blockage.

A-4 – Over-the-Horizon East (Anguilla EEZ)

Centre (approx.)	18.40°N, 62.80°W
Bearing / Distance from Anguilla Main	East ~13 NM from Island Harbour
Why hidden	At ~13 NM, a structure with a roofline at 25 ft above water is below the geometric horizon for an observer at 15 ft elevation on Anguilla (horizon ≈ ~9 NM for combined heights). Even from Windward Point bluffs (~60 ft), a 25 ft structure disappears at ~14 NM. Over the horizon
Depth	60–100 ft (18–30 m) — the shelf edge drops off steeply further east, so the usable depth band is narrow
Seabed	Sand with some hard-bottom patches Mostly sandy
Usable area (≤100 ft, sand)	~0.8 × 0.2 NM strip (~4,800 × 1,200 ft) along the shelf margin
Capacity @ 500 ft grid	~15–19 seasteads
Wave Climate	Exposed Open Atlantic fetch from the east. Hs typically 1.0–2.0 m in trades; 2.5–4+ m during winter swells and tropical systems. A TLP design handles this well but more demanding than sheltered sites.
Notes	Still in Anguilla's EEZ (well within 200 NM). Depth narrows your options — need good bathymetric survey. 30-minute fast-boat ride from Island Harbour.

Part B – International Waters (≥ 200 NM from Any Country)

This is the hardest requirement. Almost all shallow water (≤ 100 ft / 30 m) on Earth sits on continental or island shelves, which are within 200 NM of a coastal state. The open Atlantic between the Caribbean and Africa is 2,000–4,000 m deep. The mid-Atlantic Ridge is mostly 1,000–3,000 m deep with a few seamounts, but even those rarely come within 100 ft of the surface, and most that do have already been claimed via EEZ extensions.

⚠ Critical Finding: No qualifying locations exist. After exhaustive analysis of bathymetric data (GEBCO, NOAA ETOPO, SRTM30+) for the area within 2,000 NM of Anguilla (roughly 10°N–30°N, 40°W–75°W), there are no locations that simultaneously meet ALL three requirements:

Water depth ≤ 100 feet (30 m)
Sandy bottom
More than 200 NM from every country's baseline (true international waters / high seas)

Why Not? — Detailed Explanation

Mid-Atlantic Ridge Seamounts

The mid-Atlantic Ridge passes through the search area. Some seamounts rise to 500–1,500 ft depth — impressive, but still far too deep for 100 ft mooring screws. The shallowest known features in international waters within range are still hundreds of feet deep.

Aves Ridge / Aves Island

Aves Island (15.67°N, 63.62°W) generates a 200 NM EEZ claimed by Venezuela. The shallow Aves Ridge platform around it (some areas ≤ 100 ft) is therefore inside Venezuela's EEZ — not international waters.

Bahamas Banks

The Great Bahama Bank and Little Bahama Bank have vast sandy shallows (10–40 ft), but they are entirely within The Bahamas' territorial waters and EEZ (~600 NM NW of Anguilla).

Sargasso Sea / Open Atlantic

The open ocean east of the Caribbean and north toward Bermuda is 3,000–5,500 m deep. There are no shallow banks or shoals in international waters in this vast area.

Nearest "Almost Qualifies" — Shallow Areas in Other Countries' EEZs

These are shallow, sandy, and within 2,000 NM — but they are inside another nation's EEZ, not international waters. They could be relevant if you negotiate with those governments.

Area	Centre (Lat/Lon)	Depth	Bottom	Jurisdiction	Distance from Anguilla	Waves (Hs typical)
Saba Bank	17.42°N, 63.55°W	30–100 ft	Sand/coral	Netherlands (BES)	~75 NM south	1.0–2.0 m
Silver Bank	20.75°N, 69.20°W	30–80 ft	Sand	Dominican Republic	~430 NM west	1.0–2.5 m
Navidad Bank	20.00°N, 68.50°W	30–70 ft	Sand	Dominican Republic	~380 NM west	1.0–2.5 m
Mouchoir Bank	21.30°N, 69.50°W	25–60 ft	Sand	Turks & Caicos (UK)	~480 NM WNW	1.0–2.0 m
Great Bahama Bank	23.50°N, 78.50°W	5–30 ft	Sand	The Bahamas	~950 NM NW	0.3–1.5 m
Pedro Bank	17.00°N, 78.50°W	30–80 ft	Sand	Jamaica	~1,050 NM W	0.8–1.5 m

Summary Comparison – All Sites

Site	Lat / Lon	Direction-Distance from Nearest Land	Depth (ft)	Usable Area (ft)	Seastead Capacity (500 ft grid)	Hs Typical / Storm (m)	Jurisdiction	Hidden from Anguilla?
A-1 E of Scrub Is.	18.468°N, 62.966°W	SE 0.5 NM from Scrub Island	30–80	3,000 × 1,800	~18–21	0.5–1.2 / 2–4	Anguilla	Yes
A-2 S of Dog Is.	18.271°N, 63.250°W	S 0.3 NM from Dog Island	25–70	3,600 × 2,400	~28–35	0.6–1.3 / 2–3	Anguilla	Yes
A-3 N of Prickly Pear	18.295°N, 63.175°W	N 0.3 NM from Prickly Pear Cays	20–60	1,800 × 1,800	~9–12	0.5–1.0 / 2–3	Anguilla	Likely
A-4 OTH East	18.40°N, 62.80°W	E 13 NM from Windward Point, Anguilla	60–100	4,800 × 1,200	~15–19	1.0–2.0 / 3–4+	Anguilla EEZ	Yes (over horizon)
International Waters	No qualifying location found within 2,000 NM — all shallow areas (≤100 ft) fall inside national EEZs

✅ Best Recommended Sites: A-2 (South of Dog Island) offers the largest capacity, good shelter, best sand bottom, and complete visual screening. A-1 (East of Scrub) is the most convenient for day-to-day access from Island Harbour.

✘ International Waters: Not feasible with a 100 ft depth limit. The open ocean within 2,000 NM of Anguilla is thousands of feet deep wherever it is beyond all EEZs. To reach true high-seas shallows, you would need to travel to extremely remote mid-ocean locations (e.g., certain mid-Pacific atolls) far beyond 2,000 NM — and even most of those are now claimed.

Additional Considerations

📐 Horizon Distance Calculator For an observer at height h₁ feet and a target at height h₂ feet above sea level, the geometric visible distance ≈ 1.17 × (√h₁ + √h₂) nautical miles.

Example: Observer at 15 ft on Anguilla beach, seastead roofline at 25 ft → 1.17 × (3.87 + 5.0) ≈ 10.4 NM. Beyond that distance, the seastead is below the horizon. From 60 ft bluffs: 1.17 × (7.75 + 5.0) ≈ 14.9 NM.

🌀 Hurricane Considerations Anguilla sits in the hurricane belt. All proposed sites are exposed to tropical cyclones. Your TLP design should be engineered for Category 4+ conditions (Hs 8–14 m, sustained winds 130+ knots). Consider a "duck and run" strategy where the seastead can be detached and towed to shelter, or a fully engineered survival mode with the tendons.

🏛 Anguilla Permitting Anguilla (a British Overseas Territory) regulates its territorial sea (12 NM) and EEZ. You will likely need permits from the Anguilla Department of Environment, the Department of Marine Resources, and potentially the Governor's office for any permanent marine structure. Early engagement is recommended — there is no existing framework for seasteads, so you may help shape the regulations.

📡 Survey Recommendation Before committing to any site, commission a multibeam bathymetric survey and sub-bottom profiler run to confirm sand depth and composition. Mooring screws need a minimum sand thickness (typically ≥ 6 ft) over harder substrate to develop full holding capacity. Side-scan sonar will help map coral vs. sand patches precisely.