Flooding level progress bar with background
Who it’s for
City operators and water management engineers monitoring rivers, drainage channels, or flood sensors ask “how high is the water relative to the danger level?” They use this bar on dedicated situation screens or public-facing displays where a background image gives the widget a polished, site-specific look.
What it does
A sensor reading 0.3 m fills the bar to 6% of its 5 m scale in blue — Normal — over the preset background. At 1.8 m the bar fills to 36% and turns orange — Warning. Above 3 m the fill turns red — Critical.
- Horizontal progress bar that fills left to right as the water level rises, scaled from 0 to 5 m by default
- Color-coded fill that changes across three flood severity segments: blue for Normal, orange for Warning, red for Critical
- Decorative background image bundled with the widget, with a white overlay that keeps the text readable
- Numeric value and label displayed alongside the bar
- Last-updated timestamp showing how long ago the reading arrived
- Shows one sensor’s data; it does not chart history or compare multiple locations
How to set up
Data keys
| Key | Role | Type | Description |
|---|---|---|---|
flooding | Bar value | Timeseries | Water level in meters; change the key name to match your device’s telemetry key |
The widget ships with a simulated function datasource key labeled Flooding level, so it draws random values until you point the datasource at a device and rename the key.
To point it at your own device: open the dashboard in edit mode, open the widget’s Datasources, pick the entity or entity alias, and replace the function key with the key your device reports.
If the key has never reported, the bar renders empty.
Value ranges
| Range (m) | Level | Color |
|---|---|---|
| 0–1 | Normal | Blue |
| 1–3 | Warning | Orange |
| 3+ | Critical | Red |
How to customize
- To swap the background image — open the widget settings and set Background to a different image or switch to a solid color.
- To adjust how much the background shows through — change the Overlay opacity; lower values reveal more of the image, higher values push it further back.
- To change the bar scale — set Tick min and Tick max to match the physical range of your sensor or channel.
- To use your own flood thresholds — edit the Color ranges; the bar segments shift automatically.
- To change the unit label — set Units to your preferred label (e.g.
ftfor feet). - To hide the value or timestamp — turn off Show value or Show date.
Tips
- Set Tick max to the physical capacity of the channel or containment area, not just the Critical threshold, so the bar shows how close to absolute maximum the level is.
- If the background image reduces contrast, raise the Overlay opacity to keep the text readable from a distance.
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