Flood risk doesn't stop
at a county border

Published 28 September 2026  ·  A RISE update  ·  6–8 minute read  ·  Updated 1 October 2026

Every county boundary we work within sits alongside another county with the same rivers and the same weather systems. The Great Ouse doesn't stop being the Great Ouse the moment it crosses from Buckinghamshire into Bedfordshire and beyond into Cambridgeshire. The Cherwell links Northamptonshire and Oxfordshire before it reaches the Thames. Flood risk, in other words, is a catchment problem before it's an administrative one.

Counties bordering our core four, and what connects them

• Warwickshire borders Northamptonshire and Oxfordshire directly, and shares the same broad clay-vale and river-valley geology that drives much of the surface water risk we see in our own core counties.
• Leicestershire borders Northamptonshire, and, like it, sits across a mix of clay and limestone geology with a long history of localised flood action groups forming after specific incidents — the same pattern we've documented in our own counties.
• Hertfordshire and Berkshire border Buckinghamshire and Oxfordshire respectively, and share the same Chalk aquifer geology running through the Chilterns that makes groundwater flooding, specifically, a live risk on both sides of the county line.
• Cambridgeshire sits directly downstream of Bedfordshire on the Great Ouse system, meaning upstream flood management decisions in our own core counties have a direct, documented effect on flood risk further down that same river.

County lines are not the only thing moving. Some counties are already split into several unitary councils (Northamptonshire has two Lead Local Flood Authorities, Bedfordshire three), and the government is reorganising others. In September 2026 it paused decisions in 14 areas for review. Whichever council is your Lead Local Flood Authority on the day you flood owns the Section 19 duty.

The legal framework travels with you

Section 19 of the Flood and Water Management Act 2010 is not specific to our four counties — it applies to every Lead Local Flood Authority in England. The same discretionary "necessary or appropriate" duty to investigate, the same publish-and-notify requirement once an investigation happens, and the same permissive (not compulsory) powers we've written about extensively apply whether your postcode sits in Buckingham or in a bordering county we don't yet formally serve. If you live just outside our core operating area and have been told "that's not really anyone's responsibility" after a flood, the legal reality is almost certainly more nuanced than that — the same as it would be inside our four counties.

Where we are today

To be direct about it: RISE's formal consultancy work is currently based in Buckinghamshire, Oxfordshire, Northamptonshire and Bedfordshire, and that's where we can commit to the depth of local council-specific knowledge that makes our Section 19 work effective. We're watching activity in the bordering counties above closely, and this article exists because the underlying flood risk, geology and legal framework genuinely don't stop at a county line — even where our formal service area, for now, does.

If you're inside our four core counties, the RISE Section 19 Case Assessment is available today. If you're just outside them and want to understand your own position under the same national law, get in touch — 07391 151719 — and we'll tell you honestly whether we're the right fit yet.

Sources: General UK river catchment and county geography; Flood and Water Management Act 2010 (national application, legislation.gov.uk); British Geological Survey Chalk aquifer mapping.