Dorset's 'At Risk' areas

More facts on climate change and nature loss in Dorset

A recent Dorset Council report (Sep 2026) on adaptation and resilience to climate change and nature loss in the county is extensive but one thing it lacks is a map of Dorset's most vulnerable areas from sea level rise, flooding, forest and heathland fires, and drought.

This AI summary (note this source and check any critical information) could be a good basis for such a map if anyone has the time and skill to produce one:

Summary

Christchurch, Poole, and Weymouth are among the areas in Dorset most vulnerable to sea level rise and coastal flooding, while the county's extensive lowland heaths around Wareham and Sandford face the highest wildfire risks.

Sea Level Rise and Coastal Flooding

Low-lying coastal and estuarine zones face increasing risks from rising tides and extreme weather:

• Christchurch: Highly vulnerable due to low-lying land around Christchurch Harbour and the convergence of the Rivers Stour and Hampshire Avon.

• Poole and Sandbanks: Extensive coastal parts, including Hamworthy, Upton, Whitecliff, Lilliput, and the Sandbanks peninsula, are projected to be heavily impacted by 2050 with the potential to be inundated.

• Weymouth: Town centre locations near low-lying ground and the harbour (such as the Swannery area) face long-term combined risks from tidal, river, and groundwater flooding.

• Wareham and Purbeck: Low-lying villages and shorelines surrounding Poole Harbour and the River Frome floodplain are increasingly exposed to tidal encroachment.

• West Dorset Coast: Specific pockets near river mouths and beaches—including Bridport, West Bay, Burton Bradstock (River Bride), and Seatown—are vulnerable to both rising sea levels and flash flooding.

Inland and Surface Water Flooding

• River Catchments: Low-lying properties and roads along the major river systems—the Stour, Frome, and Piddle—experience seasonal riverine and groundwater flooding, particularly around Blandford Forum, Gillingham, and Wimborne Minster.

• Surface Water: Surface water runoff affects thousands of properties across the wider county independent of direct river or coastal flooding.

Forest and Heathland Fires

• Sandford and Wareham: These sectors feature dense concentrations of precious lowland heath and forest that dry out rapidly during extended hot spells, making them primary wildfire concerns for the Dorset & Wiltshire Fire and Rescue Service.

• East Dorset Heaths: Fragmented heathland interfaces near urban developments and major roadways remain susceptible to blizzards of dry vegetation ignited by hot weather or human activity.

Drought

There are no major reservoirs in Dorset but there are several artificial and managed water storage sites in and immediately bordering Dorset.

Surface reservoirs in the Wessex region (including Dorset) are currently (Oct 2026) at 25% of total capacity, and parts of Dorset are under a severe drought declaration following an exceptionally dry spring and summer.

Regional Water & Ground Conditions

• Surface Reservoirs: Storage across the Wessex Water surface reservoirs is well below the long-term average for October at 25% capacity.

• Groundwater Levels: Monitoring boreholes across Dorset (such as at Badbury Rings, Doles Ash, Delcombe Wood, and Horton Inn) are predominantly classified as LOW compared to long-term averages.

• River Flows: Many local rivers and streams are running below normal or low, with environmental stream supports active in locations like the River Piddle to help boost flows.

Current Local Water Data (As of October 20, 2026)

Of the six boreholes in Dorset the levels at four are presently designated 'low':

• Delcombe Wood borehole: 124.53m (State: LOW)

• Doles Ash borehole: 113.73m (State: LOW)

• River Stour at Blandford: 0.07m (State: LOW)

• River Frome at Stinsford: 0.03m (State: LOW)

• Ashmore borehole: 132.34m (State: NORMAL)

• Iwerne Hill Farm borehole: 3.50m (State: NORMAL)

21 October 2026

Submitted by Richard Thomas, SuSAC