About
Monitoring Cornwall shows which of the county's rivers are high and rising, which storm overflows are spilling, how clean the water is at each beach, and what the rain and the rivers are forecast to do next. All of it is public data, published by the Environment Agency, South West Water, the Met Office and others on their own sites; here it's on one map, and most of it is checked every five minutes.
On the map
- Flood warnings
- The Environment Agency's flood warnings and alerts in force in Cornwall, outlined on the map, with a banner across the top of the page while any are in force.
- Rivers and rain
- About 130 river level, tidal and rain gauges, reporting every 15 minutes. River gauges are green within their typical range and red above it, with an arrow while the level is rising or falling. Rain gauges have a 48-hour rain forecast, and the gauges on the Tamar, Lynher, Fowey and Camel a fortnight's river flow forecast.
- Storm overflows
- Nearly 400 storm overflows run by South West Water in Cornwall, which release storm sewage into rivers and the sea when heavy rain overloads the sewers. The map opens on those spilling now, and each one's popup shows its spills over the last 30 days and its yearly totals.
- Coast
- Cornwall's 90 designated bathing waters, coloured by their latest annual classification, with recent sample results and, from May to September, the Environment Agency's daily pollution risk forecast. Wave buoys and weather stations around the coast, from Bude to St Mary's Sound, and two more offshore, the Seven Stones lightvessel and the E1 buoy, report waves, wind and sea temperature between them.
- Background
- Rivers, streams, railways and the A30, A38 and A39, from OpenStreetMap. Rivers end at the county boundary rather than running out to sea down the middle of each estuary, and heritage railways aren't shown.
Data sources
| Layer | Source | Licence |
|---|---|---|
| Flood warnings and alerts | Environment Agency real-time flood-monitoring API, checked every 5 minutes, with flood area outlines from the same API | Open Government Licence |
| River, tidal and rain gauges | Environment Agency real-time flood-monitoring API, checked every 5 minutes. This uses Environment Agency flood and river level data from the real-time data API (Beta). | Open Government Licence |
| Rain forecast | Open-Meteo weather forecast API, hourly rainfall for the next 48 hours at each rain gauge, fetched when a forecast is opened and kept for 15 minutes | CC BY 4.0 |
| River flow forecast | GloFAS river discharge from the Copernicus Emergency Management Service, through Open-Meteo's flood API, for the Tamar, Lynher, Fowey and Camel. GloFAS models rivers on a grid about 5 km across, so its flows are scaled to match each river's long-run mean flow, and its forecasts are a guide to the days ahead rather than a measurement. | CC BY 4.0 |
| Mean river flows | Data from the UK National River Flow Archive, used to scale the modelled flows | NRFA terms |
| Storm overflows | South West Water's storm overflow activity feed, checked every 5 minutes | CC BY 4.0 |
| Storm overflow yearly totals | Event Duration Monitoring annual returns. © Environment Agency copyright and/or database right. | Open Government Licence |
| Bathing waters | Environment Agency bathing water quality data: classifications, in-season samples and daily pollution risk forecasts, checked every hour | Open Government Licence |
| Offshore stations | Met Office observations from the Seven Stones lightvessel and the E1 buoy, as republished by NOAA's National Data Buoy Center, checked every 30 minutes | NOAA terms |
| Wave buoys and coastal weather stations | Real time data displayed on this page are from the Regional Coastal Monitoring Programme, made freely available under the terms of the Open Government Licence. Please note that these are real-time data and are not quality-controlled. Read through the Channel Coastal Observatory's API every 30 minutes. | Open Government Licence |
| Boundary | OpenStreetMap relations 57537 (Cornwall) and 158039 (Isles of Scilly) | ODbL |
| Rivers and streams | OpenStreetMap waterway=* via the Overpass API | ODbL |
| Railways and stations | OpenStreetMap railway=* via the Overpass API | ODbL |
| Major roads | OpenStreetMap highway=* via the Overpass API | ODbL |
| Place names | OpenStreetMap place=town, village and hamlet via the Overpass API, which rain gauges are named after | ODbL |
| Basemap | Esri World Light Gray / Dark Gray Canvas | Esri terms |
Licence
The code is open source under the MIT licence, at github.com/aallan/monitoring-cornwall. The data stay under their publishers' licences, listed above. Corrections to rivers, railways or roads are best made on OpenStreetMap, and reach this map when it's next rebuilt.