The Environment Agency is urging homes and businesses in Dorset to be prepared for possible flooding from groundwater as levels rise after recent heavy rain.
Groundwater levels are currently very high and continuing to rise. Flood Alerts remain in force for West Dorset and Cranborne Chase and a Flood Warning for the South Winterbourne Valley.
In West Dorset groundwater levels are starting to peak, but could rise steeply in response to more rainfall.
This could again lead to flooding of the A35 at Winterbourne Abbas. The A354 at Coombe Bisset could also be affected by further rain forecast for Sunday.
Many locations in Dorset have seen double the average rainfall for December and rain totals for the winter as a whole are the highest since the winter of 2000.
The Agency continually monitors groundwater using a telemetry system that automatically sends data from a series of monitoring stations 24 hours a day.
It also checks flood defences to ensure they are functioning effectively and takes action to remove blockages from rivers to ensure they flow freely.
The Environment Agency’s free service can send you messages by phone, email, text message or fax when a flood is possible in your area.
Call Floodline on 0845 988 1188 (24 hour service) or check online to find out if they are available in your area (https://fwd.environment-agency.gov.uk/app/olr/home).
Many of the actions for preparing for groundwater flooding are the same as those for flooding from rivers or the sea.
The risk of groundwater flooding and the precautions people can take to protect their homes are explained in the ‘Flooding from Groundwater’ leaflet, available from http://www.environment-agency.gov.uk
Lead Local Flood Authorities are responsible for managing the risk of flooding from groundwater. The LLFAs work in partnership with other organisations, including the Environment Agency, district councils, water and sewerage companies to manage this risk.
For now, the Environment Agency is responsible for providing and maintaining the flood warning services.
Flooding from groundwater happens when the level of water within the rock or soil that makes up the land surface (known as the water table) rises.
The level of the water table changes with the seasons due to variations in long-term rainfall and water abstraction.
When the water table rises and reaches ground level, water starts to find its way to the surface and flooding can occur.
There are some key features of flooding from groundwater:
• Flooding will usually occur days or even weeks after heavy or prolonged rainfall • Flooding may ‘pool’ in low lying areas and can form springs in unlikely places, such as hillsides • Flooding may occur for a long time, often lasting several weeks.
Think and prepare now for what you’ll do if flooding occurs where you live • If you have a personal flood plan, you should put it into action • Move your valuables from basements and cellars • If you have a pump, make sure it’s serviced and working effectively • Keep your drains and gulleys around your home free from debris • Check the Environment Agency website for local water levels and flooding information.
• If you own part of the river bank, you should keep the banks and bed of the river clear of debris.