A real-time river level monitoring app built for paddlers — kayakers, canoeists, paddleboarders and anyone who needs to know what a river is doing before they get on the water. Live demo

PaddleGauge lets you search for any river in England and quickly see the monitoring stations along it, including the latest water level readings and a plain-English status badge showing whether the river is running high, normal, or low.

Data is sourced from the Environment Agency's Real Time flood-monitoring API.

• River search with live autocomplete across all active monitoring stations in England
• Station cards showing the latest reading for each station in metres or m³/s
• 5-state status badges — High, Nearly High, Normal, Nearly Low, Low — calculated against the Environment Agency's typical range data for each station
• Clean dark UI designed for quick at-a-glance use

Vanilla JavaScript, HTML, CSS. No frameworks or build tools — just a frontend making direct calls to a public API.

PaddleGauge is an early build. Improvements are already well underway, with a longer-term vision to become the go-to knowledge platform for paddlers — not just a gauge viewer, but a place where community experience is attached to river levels.

• Desktop and tablet view - expand beyond mobile-first to serve desktop and tablet users
• Backend with scheduled data fetching — a server will fetch and cache data every 15 minutes, matching the API's update frequency, significantly improving load times for rivers with many stations
• Altitude-based station ordering — stations ordered source to sea using elevation data, giving a more intuitive picture of how a river is running along its length
• Reading trend indicator — a trajectory arrow showing whether a station's level is rising or falling based on recent readings
• Improved measure selection — smarter logic to always surface the most relevant reading type for paddlers
• Interactive mapping — plot river gauges on a map and allow users to select gauges directly
• Expansion - expand to cover the entire UK by fetching Welsh, Scottish and Northern Irish APIs

• Level history graphs (last 24h / 7 days)
• Save favourite gauges
• Go into gauges on a river for a more detailed view of the data

This is where PaddleGauge really starts to differentiate. The goal is to attach paddler knowledge to gauge levels:

• Log paddle sessions and attach ratings to a gauge level ("1.4m – perfect level", "1.8m – pushy")
• Push notifications to collect the data
• Collate paddling behaviour data from these ratings
• Hazard reports — downed trees, broken weirs, and access issues that display for set time periods
• Community level comments and recommended runnable ranges

• Level alerts — notify when a river reaches a runnable level or when it is approaching empty or flood
• Rainfall correlation — show upstream rainfall data
• Level forecasts based on recent trends
• Personal paddling history
• Location sharing as a safe paddling feature

• User accounts
• River condition reports and community photos
• Hazard warning updates and comments
• Recommended lines and portages

This is the long-term plan for the product — paddler knowledge attached to levels that anyone can pull from a public API, but no one else has.

A freemium model: free tier covers gauges and basic levels, paid tier unlocks alerts, history, forecasts and trip planning tools.

"Strava meets weather and river level planning for paddlers."

A place to check levels, conditions, hazards, session history and community reports — all in one place.

This app uses Environment Agency flood and river level data from the real-time data API (Beta).