Flood Alert Issued for Groundwater in Vernham Dean, Upton, and Bourne Valley

Alert Details

The Environment Agency has issued a Flood Alert for groundwater flooding in the Solent and South Downs area. The alert was raised following high groundwater levels recorded in the Bourne Valley region.

Affected Areas

The alert covers several locations within Hampshire, specifically:

• Vernham Dean
• Upton
• The Bourne Valley
• Hurstbourne Tarrant
• Stoke
• St Mary Bourne

What You Should Do

Residents across the Bourne Valley are advised to take the following actions:

• Prepare property resilience measures to protect against water ingress.
• Ensure that any installed pumps are in working order in case levels begin to rise again.
• Monitor septic tanks, as they may struggle to operate properly due to the high water table.

Expected Conditions

Groundwater levels in the Bourne Valley are currently high. In Upton, levels are reported as high but steady, with flooding already affecting a small number of cellars. At the borehole in Vernham Dean, levels peaked on Wednesday, February 25, 2026, and have since fallen by 29cm. While septic tanks are struggling, no property impacts are currently expected in Vernham Dean, Hurstbourne Tarrant, Stoke, or St Mary Bourne.

Timeline

The alert was issued on March 3, 2026. Mostly dry weather is forecast from Tuesday, March 3, through Saturday, March 7, 2026, which should allow groundwater levels to continue a slow decline over the next week. The Environment Agency is monitoring the situation closely and will provide an update by 18:00 on March 10, 2026.