On the beach
Right now
Sample dataIllustrative conditions — the live Open-Meteo marine feed wasn't reachable, so these are deterministic placeholder values that will be replaced automatically once the feed is available.
7-day outlook
Sample dataModeled placeholder forecast for demonstration — will be replaced by a live marine-weather feed.
Sea temperature
Next 7 days, °C
Wave height
Next 7 days, metres
View as table
| Day | Sea temp (°C) | Wave height (m) |
|---|---|---|
| Wed 2 | 26.2 | 0.3 |
| Thu 3 | 25.7 | 0.3 |
| Fri 4 | 25.4 | 0.3 |
| Sat 5 | 25.6 | 0.3 |
| Sun 6 | 26.0 | 0.3 |
| Mon 7 | 26.5 | 0.3 |
| Tue 8 | 26.6 | 0.3 |
Water quality history
Official EEA classification, one rating per bathing season, 2015–2025 — real data reported by national authorities.
- 2015: Sufficient2015
- 2016: Sufficient2016
- 2017: Sufficient2017
- 2018: Sufficient2018
- 2019: Good2019
- 2020: Good2020
- 2021: Good2021
- 2022: Excellent2022
- 2023: Excellent2023
- 2024: Excellent2024
- 2025: Excellent2025
Excellent in the most recent season, and 7 of 11 classified years rated Excellent or Good.
- Excellent
- Good
- Sufficient
- Poor
- Not classified
View as table
| Year | Classification |
|---|---|
| 2015 | Sufficient |
| 2016 | Sufficient |
| 2017 | Sufficient |
| 2018 | Sufficient |
| 2019 | Good |
| 2020 | Good |
| 2021 | Good |
| 2022 | Excellent |
| 2023 | Excellent |
| 2024 | Excellent |
| 2025 | Excellent |
Typical sea temperature by month
Modeled estimatePlausible seasonal climatology derived from latitude, for illustration — not a measured average.
Monthly sea temperature
Typical range across the year, °C
View as table
| Month | Typical sea temp (°C) |
|---|---|
| Jan | 15 |
| Feb | 14 |
| Mar | 15 |
| Apr | 17 |
| May | 19 |
| Jun | 22 |
| Jul | 23 |
| Aug | 24 |
| Sep | 24 |
| Oct | 22 |
| Nov | 19 |
| Dec | 17 |
Location & nearby beaches
Nearby beaches
- Etang Du Moulin Neuf29 kmMorbihan
- Lac de Tremelin34 kmIlle-et-Vilaine
- L'Ile Aux Pies35 kmIlle-et-Vilaine
- Bassin de Conleau45 kmMorbihan
Distances calculated as straight-line (haversine) from official coordinates.
Getting there & around
- Easy by car — there's parking close to the beach.
- Bus stop: Taupont - Les Belles Rives, about ~290 m away.
Food, stays & town
- Nearest town: Ploërmel, about ~2.4 km away.
- 2 places to eat within 1 km Closest is Cafe du Lac, about ~100 m away.
- 3 places to stay mapped nearby Closest is Camping du Lac Ploermel, about ~90 m away.
What kind of beach is this?
This beach belongs to a small coastal village. It's usually calmer than a resort or town beach, though a popular village spot can still fill up on the best summer days.
Estimated from OpenStreetMap surroundings data (ODbL).
- Families
- Water sports
Is the water clean at Lac Au Duc?
Lac Au Duc sits on a stretch of coast classed as a lake bathing site, carrying an official EU Bathing Water rating of Excellent for the 2025 season. Under the EU Bathing Water Directive, national authorities test for intestinal enterococci and E. coli through the season and report the results the following spring — the 2025 rating was published in spring 2026, and 2026's won't follow until spring 2027. In addition to that yearly rating, some national authorities — for Croatia, the national environmental authority — publish individual water sample results during the season itself, ahead of the annual report. It sits in Morbihan. There's parking about ~80 m from the beach.
Over the 11 classified seasons on record, 7 have come back Excellent or Good — a track record worth checking each year rather than assuming. The most reliable swimming window here typically runs from July–September, with the sea usually at its warmest around August. Outside that window the water is cooler and often quieter. It's been a consistently reliable spot too — the rating has held at Excellent for 4 straight years. The nearest town, Ploërmel, is about ~2.4 km away.
That “Excellent” label comes from a full season of official water sampling, not a single test — it's one step on a four-point scale (Excellent, Good, Sufficient, Poor) reassessed once a year. Today's actual conditions can differ from the seasonal average, so for a live snapshot see the “Right now” and 7-day outlook panels above. There are 2 places to eat within a kilometre — Cafe du Lac is the closest, about ~100 m away.
Frequently asked questions
Is Lac Au Duc safe to swim in?
Lac Au Duc is rated Excellent for 2025 — the top EU Bathing Water classification — with 7 of 11 classified seasons rating Excellent or Good, so yes. It's also held steady at Excellent for 4 straight years.
What's the current water temperature at Lac Au Duc?
For Lac Au Duc, the ~26°C figure above is a stand-in value, not a live reading — the marine-weather feed was unreachable when the page last built, and it'll swap in automatically once the feed responds again. That's the reading right off Morbihan. On the modeled climatology here, August usually runs warmest.
When should you plan a swimming trip to Lac Au Duc?
If you're planning around water temperature, July–September is the window to target — the modeled sea temperature is typically highest then. That applies to the water around Morbihan. Within that window, August is typically the single warmest month.
How is bathing water quality actually assessed?
Once a year, national authorities report a full season of testing for intestinal enterococci and E. coli to the European Environment Agency, which grades the season Excellent, Good, Sufficient or Poor under the EU Bathing Water Directive. A handful of countries, including Croatia via IZOR, also publish individual in-season samples ahead of that report — Lac Au Duc doesn't have that feed set up yet.
Is there parking near Lac Au Duc?
By car, it's easy — parking is right by the beach. By bus, the nearest stop is Taupont - Les Belles Rives, about ~290 m away. The nearest town is Ploërmel, about ~2.4 km away.