Understanding the tides at Inch Island is essential whether you're visiting the Inch Wildfowl Reserve for birdwatching, planning a fishing trip, or simply curious about the rhythm of Lough Swilly. This page provides everything you need to know about tides around Inch Island.
Where to Check Today's Tide Times
For the most accurate, up-to-date tide predictions for Inch Island, we recommend these trusted sources:
| Source | Coverage | Link |
|---|---|---|
| TideKing | Inch Island specific | tideking.com/Inch-Island |
| Lough Swilly Marina | Fahan (1km from causeway) | loughswillymarina.com/tides |
| TidesChart | Buncrana | tideschart.com/Buncrana |
| TideTime | Buncrana | tidetime.org/buncrana |
Note: Inch Island sits in the middle of Lough Swilly. The Lough Swilly Marina at Fahan is the closest tide station to the Inch Island causeway. Buncrana tide times (4km north) are also very accurate for Inch Island.
Understanding Lough Swilly Tides
Lough Swilly is a deep glacial fjord stretching from Buncrana in the north to Letterkenny in the south. Inch Island sits in the inner lough, connected to the mainland at Burt by the causeway built across the reclaimed land.
Tidal Range
The tidal range in Lough Swilly varies significantly between spring tides (around the new and full moon) and neap tides (around the first and last quarter moon):
| Tide Type | High Water | Low Water | Range |
|---|---|---|---|
| Mean High Water Springs (MHWS) | 4.3m | — | — |
| Mean High Water Neaps (MHWN) | 3.2m | — | — |
| Mean Low Water Neaps (MLWN) | — | 1.9m | — |
| Mean Low Water Springs (MLWS) | — | 0.5m | — |
| Spring Tidal Range | — | — | ~3.8m |
| Neap Tidal Range | — | — | ~1.3m |
Typical Tide Cycle
Lough Swilly, like most of Ireland's Atlantic coast, experiences semi-diurnal tides — two high tides and two low tides roughly every 24 hours and 50 minutes. This means:
- Two high tides per day (approximately 12 hours 25 minutes apart)
- Two low tides per day (approximately 12 hours 25 minutes apart)
- Tide times shift later by about 50 minutes each day
Spring vs Neap Tides
- Spring tides occur around the new moon and full moon. These produce the highest high tides and lowest low tides — the greatest tidal range.
- Neap tides occur around the first quarter and last quarter moon. These produce moderate high and low tides — the smallest tidal range.
Why Tides Matter at Inch Island
For Birdwatching
Tides have a dramatic effect on birdwatching at the Inch Wildfowl Reserve:
At low tide:
- Extensive mudflats are exposed around the reserve
- Wading birds (curlews, redshanks, godwits) spread out across the flats to feed
- Birds may be distant and harder to observe from the hides
At high tide:
- Rising water pushes birds closer to shore and the hides
- Excellent close-up viewing opportunities
- Roosting flocks congregate in predictable locations
Best birdwatching times:
- 1–2 hours before high tide — birds moving closer as water rises
- 1–2 hours after high tide — birds still concentrated before dispersing
- Rising tide generally better than falling tide for viewing
The mudflats between Inch Island and the mainland (around the Tready and Farland embankments) are particularly productive for waders when the tide is right.
For the Causeway
Unlike some tidal causeways in Ireland, the Inch Island causeway is a permanent raised road that is accessible at all times, regardless of tide. You will never be cut off by the tide.
However, understanding the tides helps you appreciate the landscape. At low tide, you'll see exposed mudflats on both sides of the causeway — these are the remnants of the tidal flats that once covered this area before the Victorian land reclamation project.
For Fishing
Anglers fishing Lough Swilly around Inch Island should be aware of tidal movements:
- Incoming tide (flood) often brings fish closer to shore
- Outgoing tide (ebb) can be productive at specific locations
- Slack water (around high and low tide) can be good for certain species
The waters around Inch Island are known for bass, flounder, and mullet. Local knowledge and tide timing significantly improve success.
For Boating and Water Sports
If you're launching a boat or kayak, tide times are essential:
- Lough Swilly Marina at Fahan (just south of the Inch Island causeway) offers berthing and tide information
- Rathmullan on the western shore has a popular pier and slipway
- Strong tidal currents can occur in narrow channels
Marina contact:
- Phone: +353 74 936 0008
- Mobile: +353 86 108 2111
- Email: [email protected]
Tide Prediction Accuracy
How Tide Times Are Calculated
Most tide prediction services calculate Inch Island times based on nearby reference stations. The primary tide stations for this area are:
- Londonderry (Derry) — approximately 15km southeast
- Galway — used as a northwest Ireland reference point with time offsets
Predicted times are typically accurate to within 10–15 minutes under normal conditions. However, actual tides can vary due to:
- Atmospheric pressure — Low pressure raises sea levels, high pressure lowers them (approximately 1cm per millibar)
- Wind — Strong onshore winds can raise tides; offshore winds can lower them
- Storm surges — Can significantly raise or lower actual water levels
Important: Tide predictions are not suitable for navigation. Always allow a safety margin and use official nautical charts for any marine activity.
Sunrise, Sunset and Daylight
Tide times are most useful when combined with daylight hours. In winter, the short days mean some high or low tides occur in darkness.
Current daylight hours for Inch Island:
- Check timeanddate.com for precise sunrise/sunset times
Approximate daylight range:
- Summer (June): Sunrise ~5:00am, Sunset ~10:00pm (~17 hours daylight)
- Winter (December): Sunrise ~8:45am, Sunset ~4:15pm (~7.5 hours daylight)
Water Temperature
Lough Swilly water temperatures vary seasonally:
| Season | Approximate Water Temperature |
|---|---|
| Winter (Jan–Mar) | 7–9°C |
| Spring (Apr–Jun) | 10–14°C |
| Summer (Jul–Sep) | 14–17°C |
| Autumn (Oct–Dec) | 10–13°C |
The sheltered inner lough around Inch Island may be slightly warmer than the exposed outer lough.
Tidal Glossary
Understanding tide terminology helps when reading tide tables:
| Term | Meaning |
|---|---|
| High Water (HW) | The maximum height reached by the tide |
| Low Water (LW) | The minimum height reached by the tide |
| Spring Tide | Tides with greatest range (at new/full moon) |
| Neap Tide | Tides with smallest range (at quarter moons) |
| Flood | The incoming (rising) tide |
| Ebb | The outgoing (falling) tide |
| Slack Water | The period around high or low tide when there is minimal tidal movement |
| Chart Datum (CD) | The reference level from which tide heights are measured (approximately the lowest astronomical tide) |
| MHWS | Mean High Water Springs |
| MLWS | Mean Low Water Springs |
Frequently Asked Questions
Is the Inch Island causeway affected by tides?
No. The modern causeway is a permanent raised road that is accessible at all times, day or night, regardless of the tide. Unlike some Irish tidal causeways, there is no risk of being cut off.
What is the best tide for birdwatching at Inch Wildfowl Reserve?
The rising tide (1–2 hours before high water) is generally best, as birds are pushed closer to the hides and shore. Avoid low tide if you want close views — birds will be spread across distant mudflats.
How big are the tides at Inch Island?
Spring tides have a range of approximately 3.8 metres (from about 0.5m at low water to 4.3m at high water). Neap tides have a range of approximately 1.3 metres.
How often do the tides change?
There are typically two high tides and two low tides every 24 hours and 50 minutes. Tide times shift approximately 50 minutes later each day.
Are tide predictions accurate?
Predictions are typically accurate to within 10–15 minutes under normal weather conditions. Strong winds, low atmospheric pressure, and storm surges can cause actual tides to differ from predictions.
Where is the nearest tide station to Inch Island?
The Lough Swilly Marina at Fahan is the closest (approximately 1km from the causeway). Buncrana tide times (4km north) are also very accurate for Inch Island.
What affects the tides at Inch Island?
Tides are primarily driven by the gravitational pull of the moon and sun. The tidal range varies with the moon phase (spring vs neap tides). Weather conditions (wind, atmospheric pressure) can also affect actual water levels.
Can I swim at Inch Island?
While there is no designated bathing beach at Inch Island, some people do swim in Lough Swilly. The water is cold year-round (7–17°C depending on season). Always check tide times and conditions before entering the water, and never swim alone.
More Information
- TideKing — Inch Island Tides — Live tide predictions with charts
- Lough Swilly Marina — Tide tables and marina services at Fahan
- Met Éireann Marine Forecast — Official Irish weather service marine forecasts
- UKHO EasyTide — UK Hydrographic Office tide predictions
Have local knowledge about tides at Inch Island? Share your tips and help us make this guide better.