A Flood Alert was issued for Groundwater flooding in upper River Ems Valley in West Sussex on 23rd February 2026. Affected watercourses included the Groundwater.
During this event, FloodRadar monitoring gauges recorded notable rises. The River Lavant at West Street rose 0.46m, peaking at 7.43m, while the West Brook at Emsworth climbed 0.20m.
Environment Agency advice issued
Groundwater is high, very close to the surface, but slowly falling at the Compton borehole. Springs will appear, water will be in fields, and water will flow down roads, including Stoughton main road, the road from East Marden, between Cooks Lane and Barley Mow in Walderton, and the B2146 near Woodlands Lane. Groundwater will also affect a small number of cellars in Stoughton and Walderton. Only isolated showers are forecast Monday to Wednesday 25/02/2026. On Thursday 26/02/2026 a weather front is forecast to bring widespread rainfall. There is uncertainty in rainfall amounts, and predictions
Monitoring gauges during this event
| Station | River | Rise | Peak |
|---|---|---|---|
| West Street | River Lavant | +0.46m | 7.43m |
| Emsworth | West Brook | +0.20m | 2.06m |
| Havant | Hermitage Stream | +0.17m | 5.48m |
| Crosslands Drive | River Lavant | +0.16m | 0.74m |
| Chichester Tozer Way | River Lavant | +0.09m | 13.59m |
| Graylingwell | River Lavant | +0.06m | 0.67m |