“Diving” menu: sites, centres, lake bed and temperature

User guide · updated 19.10.2026

Planning a dive: where to enter the water, what you'll find below, what is regulated, and the temperature at depth.

What this menu is for

The Navleman menu, with the “Diving” tile circled. — Menu, then the “Diving” tile.

A list, in the order you'd prepare: dive sites; the bottom, in two layers computed in the app (slope, depth bands); launching ramps; then centres and shops, clubs and restricted areas. Below the list, a water temperature profile at depth.

How to use it

Open the menu

Tap Menu, bottom right, then the menu's tile. At the top: 📖 User guide for this menu (this page) and ↺ Reset maps, which switches everything off at once.

Below the list: Water temperature — “Refresh profile” gives the temperature from the surface to the bottom, offshore from your position, based on the Eawag model.

The open menu, with its list of map layers and a checkbox in front of each. — The open menu: one row per map layer.

Turn on a map layer

Tick a map layer's box to lay it over the base map; untick it to remove it. The arrow at the right of the row opens its info note: what the layer shows, its colour key, its source and what it doesn't tell you. An OFFLINE label marks a layer built into the app, which works without signal.

Turn on “Restricted areas” before choosing an entry point.

Why checkboxes? So that only what's useful right now goes on the map: ten layers switched on together become unreadable.

Two map layers ticked in the list; the arrow at the right of a row opens its info note. — Tick the box; the arrow on the right opens the layer's info note.

Reading the map

“Dive sites” and “Bottom slope” together, at Chillon: the slope, from yellow (noticeable) to pink (very steep), shows the drop-off along the shore; the icons mark the sites.

The Chillon shore coloured yellow and pink along the drop-off, with two dive site icons. — Dive sites and bottom slope at Chillon.

Tap a point: the pop-up

The site name, and “📍 on the site” or “entry point” depending on what the dot marks.
Stated Depth, Level, bottom Type, Interest (wildlife, wrecks…).
Hazards (⚠) and site rules: always visible, outside the collapsible section.
Site details (collapsible): the water entry and the underwater route.
Sources and position, then Set course / Start from here.

The dot usually marks the entry point: the stated depth is reached further out, and the pop-up tells you which way.

The pop-up for the Chillon / Château site: depth 50 m, level all levels, type cliff and rocky drop-off, interest, hazard in green, site details, sources and position. — A site's pop-up: depth, level, interest, hazards, then the details.

How the data is cross-checked

“Bottom slope” and “Depth bands” are computed in the app, offline, from swisstopo's swissBATHY3D grid (50 m cells): the slope between a cell and its neighbours, and the cell's mean depth. The temperature profile comes from Eawag's 3D model. Sites, centres and clubs come from the app's files.

The map layers in this menu

Two layers computed in the app from the built-in lake-bed data, the listed sites, and the two navigation layers that matter before getting in the water: where it's regulated, and where you get in.

The temperature comes from Eawag's 3D model (vertical profile offshore from your position), the same source as the profile in the Fish module. It's a model, not a measurement: allow for a gap of a few tenths of a degree, and more just after a blow.

Nothing here replaces proper dive planning. The app calculates no deco stops, no air supply and no conditions on the day, and doesn't say whether a site is authorised or an entry point permitted. Restricted areas and cantonal or prefectoral regulations prevail, and a local club knows more than any map.

🤿 Dive sites works offline

Listed dive sites around the lake: stated depth, required level, site type, water entry, underwater route and reported hazards.

dive site

Tip. The dot usually marks the entry point: the stated depth is reached further out, and the pop-up tells you which way.

Good to know. Most dots mark the ENTRY POINT, not the site: the stated depth is often reached more than 100 m from the marker. So the pop-up gives the distance and heading to reach it. Every position was checked against the measured bottom: those that fell on land were removed, those that don't match are marked “to be confirmed”. Descriptions are indicative, taken from their source: no deco stops, no conditions on the day, no authorisation — a local club will know more.

Source: Sites checked in October 2026 against diving sources (plongee.ch, sitesdeplongee.ch, clubs, FSSS) and regulations (Lake Geneva, Haute-Savoie); each pop-up says what confirmed it. Sites with no source at all were removed · October 2026

📐 Bottom slope works offline

The incline of the bottom, computed in the app: it's what tells a drop-off from a flat. The thresholds are set to the lake's actual distribution, so that no colour shows a slope that exists nowhere.

very steep — 30° and oversteep — 20 to 30°noticeable — 10 to 20°

Tip. From yellow (noticeable slope) to pink (very steep): a drop-off stands out at once; a flat bottom stays uncoloured.

Good to know. The angle is measured over 100 m, which smooths the relief: a cliff a few metres high shows up well below its true slope. Below 10°, nothing is coloured.

Source: local computation on swissBATHY3D © swisstopo, 50 m cells — no network request

🎚 Depth bands works offline

The bottom in four bands readable at a glance, rather than the nine steps of the navigation map.

0–20 m20–40 m40–60 mover 60 m

Good to know. These are depth bands, not certification limits or a planning aid.

Source: swissBATHY3D © swisstopo, 50 m cells, today's lake level applied

🛥 Launching ramps

Launching ramps. Built-in file: works offline.

82 points from OpenStreetMap (17 Geneva, 16 La Côte, 17 Lausanne and Lavaux, 12 Riviera and Valais Chablais, 20 French shore).

Good to know. Neither the slope, the draught nor the right of use is guaranteed — some ramps are private or charge a fee.

Source: OpenStreetMap and its contributors, ODbL licence · data as of 16.10.2026, frozen on 17.10.2026

🤿 Dive centres and shops works offline

Dive centres and shops: courses, try dives, tank fills, equipment.

15 places on the map (6 Geneva, 4 La Côte, 1 Lausanne and Lavaux, 2 Riviera and Valais Chablais, 2 French shore), 15 with a website, 14 with a phone number.

Good to know. Tank fills and rental aren't confirmed everywhere: call ahead.

Source: Official source for each place (its website, the municipality, the tourist office, the canton), rechecked in October 2026 and named in the pop-up; position taken from the official address (geo.admin.ch, IGN); distance to the water calculated on swissBATHY3D · October 2026

🐠 Diving and freediving clubs works offline

Diving and freediving clubs.

13 places on the map (5 La Côte, 2 Lausanne and Lavaux, 2 Riviera and Valais Chablais, 4 French shore), 13 with a website, 8 with a phone number.

Good to know. A club rarely welcomes visitors unannounced: get in touch first.

⛔ Restricted areas (swimming / navigation)

Areas where swimming or navigation is restricted or prohibited. Check before anchoring, diving or launching. Includes the Geneva harbour (rade), inside the Pâquis and Jet d'eau jetties: prohibited to craft without an engine (approximate outline).

Tip. Turn on before anchoring, diving or launching.

Good to know. The exact wording of the restriction prevails. An area may be seasonal, and cantonal or prefectoral orders change without this layer being updated.

Source: CIPEL — International Commission for the Protection of the Waters of Lake Geneva (survey 2025); Geneva harbour: Geneva navigation act (LNav), art. 10

What this menu tells you, and what it doesn't

What it tells you. Listed sites, the modelled bottom relief, the temperature modelled by Eawag.

What it doesn't tell you. Nothing here replaces proper dive planning: no deco stops, no air supply, no conditions on the day. The app doesn't say whether a site is authorised or an entry point permitted; a local club knows more than any map.

Navleman is a navigation aid, not an official nautical document: the official chart, the storm warning lights and the authorities' instructions always take precedence.

Open the Lake Geneva map