Water level alerts

With water level alerts you keep an eye on official gauges in Germany, the Netherlands, Norway and Finland, without a Hub and without a boat, just with your Smartboatia ID. You see the measurement of the last hours and the official forecast and set your own thresholds for high and low water for each gauge, each with a pre-warning and a warning. If a threshold is reached or expected according to the forecast, you get a push notification, and an all-clear when the level goes back again. The data comes straight from the official agencies, so the app also tells you honestly when a gauge is currently not delivering anything. Without a subscription you monitor one gauge, with the Standard subscription as many as you like.

What you get

Gauges and sources

Country	Source	Gauges	What the source supplies	Height reference
Germany	Federal Maritime and Hydrographic Agency (BSH)	136 official gauges on the North Sea and Baltic Sea	Measurement and official forecast for about 2.5 days; for many gauges also the official forecast text and on the Baltic Sea the official ranges	cm NHN
Netherlands	Rijkswaterstaat	about 183 locations, also on rivers and the IJsselmeer	Measurement and forecast for about 2.3 days	cm NAP
Norway	Kartverket	33 permanent gauges, also on Svalbard	Measurement and forecast for about 4.5 days, including the effect of the weather	cm SKN (chart datum)
Finland	Finnish Meteorological Institute (FMI)	14 gauges from Kemi to Hamina, also on Åland	Measurement and forecast for about 4.5 days, including the effect of the weather	cm MW (theoretical mean water level)

Values always in the gauge’s height reference. Smartboatia does not convert, and every display names the reference (NHN, NAP, SKN or MW). A value in Germany is therefore not directly comparable with a value in Norway or Finland. In Finland we use the mean water level because the FMI bases its warning limits on it. An info icon next to the value (detail view, thresholds and “Set thresholds”) explains the height reference in plain words, with typical normal values and the note “Values from different countries are not directly comparable. Your thresholds apply in this datum.” For Norwegian gauges it also says: “Gauge value plus charted depth gives the water depth.”
What you see in the app: the measurement of the last 21 hours and the forecast for the next 2.5 days, even if the source looks further ahead. For alerts, the forecast up to 3 days ahead counts.
Your length unit applies. Values appear in the length unit you set in the app, in push notifications too.

In the app: Menu › “Water level”

In the menu the “Water level” item is always there, with or without a boat and Hub. If one of your gauges is at pre-warning or warning, the menu shows the symbol of the highest warning level next to it.
Overview of your monitored gauges: current value, trend (rising, falling, steady), warning level and a small curve in which sections above a threshold are orange (pre-warning) or red (warning). Plus “As of” with the time and the sources.
Adding a gauge: selection with country chips (Germany, Netherlands, Norway, Finland) and below them the areas of the country, for example Baltic Sea and North Sea or, in Finland, the FMI sea areas from the Gulf of Bothnia to the Gulf of Finland, search by gauge or area, as a list or map. “Near me” sorts by your location, “Near {Boat}” by the last known position of your boat. On the map you see all gauges; those outside your selection appear paler. From 1.48.1 you can tap and select any gauge shown, including the paler ones outside the selected country or area.
Detail view for each gauge: “History and forecast” chart with measurement, forecast and your thresholds, where available with mean high water (MHW) and mean low water (MLW) for comparison. Above it a banner with the current situation, for example “High water pre-warning expected” with peak and time. For BSH gauges also the “Official BSH forecast” card with warning level and official text.
On a tablet list and detail are side by side.
The source is shown for every gauge. You find the licence information of BSH, Rijkswaterstaat, Kartverket and FMI (CC BY 4.0) under Settings › About › “Info”, section “Attribution”.

Remotely, on your phone

Push notification for pre-warning, warning and all-clear, for each monitored gauge separately (see Notifications). From 1.48.1 the warning arrives on the iPhone as a time-sensitive notification.
Triggered by the measurement or by the official forecast. If the forecast predicts that your threshold will be reached, you get the notification in advance, with the expected peak or lowest value and time.
Push notification when the data is not reliable, and a second one as soon as data is back.
Tapping opens the gauge: If you tap a water level notification, the app opens the detail view of that gauge directly.

How it works

Setting up your first gauge

Sign in with your Smartboatia ID and open Menu › “Water level”.
Confirm the “Before you start” notice once with “Understood” (see Safety notice). This applies to your Smartboatia ID, on all devices.
Tap “Choose gauge” or “Add gauge”.
Choose the country at the top and the area below, search for a place or use “Near me” or “Near {Boat}”. Switch between “List” and “Map” if needed. On the map you tap a gauge to select it; from 1.48.1 this works with any gauge shown, regardless of the selected country or area.
Tap “Monitor” next to the gauge you want.
If the gauge has no default values, “Set thresholds” opens: “There are no fixed default values for this gauge. Set your own thresholds relative to your berth.” Enter your values there.

Setting thresholds

In the detail view under “My thresholds” or “Thresholds”.
High water (“Level rises above the threshold”): “Pre-warning from” and “Warning from”.
Low water (“Level falls below the threshold”): “Pre-warning below” and “Warning below”.
High water and low water can each be switched off completely.
Values in whole centimetres in the gauge’s height reference. The dialog shows the allowed range, for example “Allowed: -1000 to 1500 cm relative to NHN (-10 m to 15 m)”. For high water the pre-warning must be below the warning, for low water above it.
Default values: For the BSH gauges on the Baltic Sea, thresholds are preset: high water pre-warning +80 cm, warning +100 cm, low water pre-warning -50 cm, warning -80 cm (all NHN). “Reset to default values” takes you back there. For the North Sea, the Netherlands, Norway and Finland there are no default values, because tides and rivers differ too much from place to place. There you set the thresholds yourself.

Sorting, renaming, removing gauges

Sorting: Drag a gauge by the handle at the top right of its card to the position you want. The order applies to your Smartboatia ID on all devices.
Renaming: via “More” › “Rename”, at most 60 characters.
Removing: The app asks Stop monitoring “{Name}”? and points out: “The thresholds of this gauge are deleted.”

Refreshing

Pull the list down to reload immediately. Otherwise the app refreshes the open screen every 5 minutes and whenever you bring it back to the foreground.

Requirements

Smartboatia ID, signed in to the app. No Hub, no boat needed. Without signing in you see the menu item with the note “Log in with your Smartboatia ID to monitor water levels.”
Smartboatia app from version 1.48.0 with an internet connection.
For push notifications: notifications allowed on your phone or tablet (see Push notifications). For water level notifications to arrive on Android with title and text and for the warning to arrive on the iPhone as a time-sensitive notification, you need the app from version 1.48.1.
For “Near me”: location access allowed. For “Near {Boat}” a boat of your own with a known position.

Permissions and subscription

What	Not signed in	With Smartboatia ID
See the “Water level” menu item	yes, with a note about signing in	yes
Search and monitor gauges, set thresholds, push	no	yes

Subscription	Monitored gauges
Without a subscription	1 gauge, with all features: measurement, forecast, thresholds, push
Standard subscription	as many gauges as you like

Which subscription counts: an active Standard subscription you bought with your Smartboatia ID, no matter which boat it is assigned to. A cancelled subscription also counts until the end of its term. A subscription that another person bought for your boat does not count for you.
Without a subscription you see in the gauge selection how many slots are used, for example “1 of 1 used (no subscription)”.
If you want to monitor a second gauge without a subscription, the app asks “Also monitor {gauge}?”: “Without a subscription you monitor one gauge, currently {previous gauge}. With the Standard subscription there is no limit.” It offers “View Standard subscription” or “Replace {previous gauge} with {new gauge}”.
When your Standard subscription ends, all gauges and thresholds stay saved. Only the gauge at the top of your list is still monitored, the others are paused (“No measurements, no alarms”). The app shows “Your Standard subscription has expired”: “Only {gauge}, the gauge at the top of your list, is still monitored. {number} are paused, your thresholds stay saved.” with the “Renew subscription” button. You decide which gauge stays active through the order: drag another gauge to the top or remove the monitored one, and the next gauge in your list becomes active.

Safety notice

Advisory service without guarantee. Water level alerts do not replace an official warning. The warnings of BSH, Rijkswaterstaat, Kartverket, FMI and the national warning services are authoritative. The app shows this once per Smartboatia ID: “Advisory service without guarantee. Official warnings are authoritative.”
Push notifications can arrive late or not at all, for example without network on your phone or when the source delivers no data (“Push messages may arrive late or not at all, for example without network or when data is unavailable.”). Only the warning goes out with high priority, on the iPhone from app version 1.48.1 as a time-sensitive notification. Pre-warning, all-clear and outage notifications are normal notifications that your phone may also deliver later in power saving mode.
The data is never fully up to date. Smartboatia fetches the values about every 15 minutes. The official agencies themselves deliver with a delay; at the BSH the measurement is typically about 30 minutes old. A fast rise can therefore already be there before it appears in the app.
Not every gauge measures. Some locations only have a forecast, in the Netherlands for example Europlatform, at the BSH many smaller locations on the North Sea such as Dagebüll, Wyk auf Föhr, Westerland, Pellworm, Amrum Odde and Süderoogsand. There all alerts are based on the forecast only.
Some gauges only deliver at times. For some locations the BSH only occasionally publishes a forecast, for example during storm surges. At any given time about a third of the BSH locations had neither a measurement nor a forecast. During that time there are no alerts there and no outage notification either. As soon as a forecast arrives again, the gauge alerts normally again.
Forecasts can be off. They are the official models as published; Smartboatia does not correct them. On 20 October 2026 the Kartverket forecast in the Oslofjord during a strong wind-driven low water was about 20 cm above the measured value. If the level is close to your threshold, a pre-warning from the forecast can therefore come too early, too late or not at all. Leave a margin between your threshold and the critical value.

Notifications

All push notifications go to you, on the phones and tablets where you are signed in with your Smartboatia ID. Title: “Water level {gauge}”.

When	Text (examples, word for word)
Pre-warning, threshold expected according to the forecast	“PRE-WARNING High water {gauge}: {time} ({day}) expected, peak {value}, threshold {value}. Based on the forecast. Level now {value}.”
Pre-warning from the official BSH forecast	“PRE-WARNING High water {gauge}: Official BSH forecast up to {value} ({day}), threshold {value} reached. Level now {value}.”
Warning	like the pre-warning, starts with “WARNING High water” or “WARNING Low water”; from 1.48.1 on the iPhone as a time-sensitive notification
Low water	like high water, with “Low water” and “lowest” instead of “peak”
Gauge without a current measurement	the same text without “Level now …”
All-clear	“ALL CLEAR {gauge}: Level dropped below pre-warning ({value}), now {value} ({time}).” or ”… rose above pre-warning ({value}) …”; without a current measurement “ALL CLEAR {gauge}: Level back below pre-warning {value} ({time}).” or ”… back above pre-warning …”
A measuring gauge delivers no measurement for 2 hours, or a source fails completely	Title “Water level data {gauge}”: “{gauge}: no new water-level data for 2 hours. We will notify you once data is back.”
Data back	“{gauge}: Current water-level data is available again.”

Times in push notifications are in the local time of the gauge, so for Finnish gauges one hour later than in Germany. The app shows times in your phone’s time zone.

No flood of notifications: If the level swings around a threshold, you do not get a new notification every time it crosses. The all-clear only comes when the level is back beyond your pre-warning.
For each outage there is exactly one “not reliable” notification and one when the data is back.
For gauges that only deliver at times, there is no outage notification during the time without data.

Messages and special cases

Situation	What you see
Gauge does not measure but has a forecast	“Forecast only. This gauge does not measure.” Alerts are based on the forecast only.
Gauge currently delivers neither measurement nor forecast	“No current data from this gauge. The source only provides values here at times.” Neutral, no outage notification.
Measuring gauge without a measurement for 2 hours, or source failed	Banner “Warnings currently unreliable”: “No new data since {time} ({duration}). Measurement and forecast show the last state. Check official warnings.” Plus a push notification.
No forecast for the gauge	“No forecast data available.”
Data outdated	Level “Data outdated”, grey
Level above or below your threshold	Banner “High water pre-warning” or “High water warning”, likewise for low water, with peak or lowest value
Threshold expected according to the forecast	“Pre-warning expected” or “Warning expected”, “According to the forecast.”
Level back beyond the pre-warning	Banner “All clear”: “Level below the pre-warning ({value}) since {time}.”
Gauge already monitored	“This gauge is already monitored.”
Gauge no longer exists	“This gauge is no longer available.”
Service not reachable	“Water levels are currently unavailable. Check your connection.”
Threshold outside the allowed range	“Please enter a value between {min} and {max}.”
Pre-warning and warning in the wrong order	for example “The pre-warning must be below the warning ({value}).”
Location access not allowed	“Allow location”: “To sort gauges by distance the app needs access to your location. You can allow it in the settings.”
Sign-in expired	“Please log in again with your Smartboatia ID.”

Offline behaviour

Monitoring runs in the Smartboatia Cloud, not on your phone. It continues when the app is closed or your phone is switched off. The push notification reaches you as soon as your phone has network again.
Without internet the app cannot load new values and shows “Water levels are currently unavailable. Check your connection.”
Gauges, thresholds and order are saved in your Smartboatia ID, the same on all devices, even after reinstalling the app.

Frequently asked questions

Do I need a Smartboatia Hub for water level alerts?

No. Water level alerts are tied to your Smartboatia ID. You only need the Smartboatia app from version 1.48.0 and a sign-in, no boat and no Hub.

Which gauges can I monitor?

Official gauges in Germany (136 BSH gauges on the North Sea and Baltic Sea), in the Netherlands (about 183 Rijkswaterstaat locations, also on rivers and the IJsselmeer), in Norway (33 permanent Kartverket gauges, also on Svalbard) and in Finland (14 gauges of the Finnish Meteorological Institute, also on Åland).

Why does my value show NHN, NAP or SKN after it?

Each gauge shows the water level in the height reference of its source: Normalhöhennull in Germany, Normaal Amsterdams Peil in the Netherlands, chart datum in Norway, theoretical mean water level in Finland. Smartboatia does not convert, so your thresholds also apply in this reference.

Why does my gauge show "Forecast only" or "No current data"?

Some locations do not measure themselves but only have an official forecast; there the alerts are based on the forecast. For some locations the BSH only publishes values at times, for example during storm surges. As soon as a forecast arrives again, the gauge alerts normally again.

How many gauges can I monitor?

Without a subscription one gauge with all features, with the Standard subscription as many as you like. What counts is a Standard subscription you bought with your Smartboatia ID. If the Standard subscription ends, all gauges stay saved, and the gauge at the top of your list is then the one monitored.

Can I rely on water level alerts alone?

No. They are an advisory service without guarantee: the official data arrives with a delay, forecasts can be off, and push notifications can arrive late or not at all. The official warnings of BSH, Rijkswaterstaat, Kartverket and FMI are authoritative.

Push notifications

Discover the Smartboatia Hub

The Hub connects your boat to the app.

Go to the Smartboatia Hub