Flood Risk Assessments in Devon

Devon and Cornwall are the only areas in England with formally designated Critical Drainage Areas. The CDA designation means the EA provides local flood risk standing advice for development in these zones, and that advice must be addressed in the planning submission regardless of the flood zone the site sits in. This is the most significant planning requirement specific to Devon from a developer’s perspective, and one that is not covered by national NPPF guidance alone.

The East Devon SFRA 2024 covers the Exe corridor and the coastal towns of Exmouth, Sidmouth, Seaton and Budleigh Salterton in detail. The Exe estuary is one of Devon’s most complex planning environments, a designated SSSI, RAMSAR site and SPA with combined tidal and fluvial flood risk from the Exe catchment. Development near the estuary at Topsham, Exminster, Lympstone and Exmouth requires careful assessment of both tidal and fluvial sources. Mid Devon’s SFRA covers the River Exe at Tiverton, the River Culm through Cullompton and the River Creedy through Crediton, all watercourses with documented flooding histories in their valley settlements.

Devon’s short, steep catchments respond rapidly to intense rainfall. The Boscastle flooding of 2004, though technically in Cornwall, is a reminder of how quickly flash flooding can develop in these catchments with minimal warning time. Finished floor levels in FRAs for Devon valley sites must account for the speed of onset, not just the eventual flood depth. Surface water flooding across Devon’s towns and villages is significant, and South West Water’s combined sewer networks in Exeter, Plymouth and Torbay are under increasing pressure.

• Development in a Critical Drainage Area, regardless of flood zone
• Development in Flood Zone 2 or 3 along the Exe, Taw, Torridge, Dart, Teign, Axe or Culm
• Coastal and estuarine development where tidal, wave overtopping and sea level rise risk must be assessed
• Development of 1 hectare or more in Flood Zone 1
• Development near the Exe estuary where SSSI, RAMSAR and SPA designations create additional requirements
• Development requiring a surface water drainage strategy under Devon County Council SuDS guidance

We understand the CDA designation and its specific planning implications in Devon in detail. We can confirm at pre-application stage whether your site is within a CDA and what assessment is required, eliminating the most common cause of avoidable EA objection in the county.

Our FRAs engage with EA river model data and coastal flood boundary datasets relevant to Devon and address the rapid catchment response characteristics specific to Devon’s steep river systems.

We have a team local to Devon for site visits and cover all Devon districts and unitary authorities: East Devon, Mid Devon, Teignbridge, South Hams, North Devon, Torridge, West Devon, Exeter City, Plymouth City and Torbay.