How flooding causes delays - and what the industry is doing to reduce them
Many sections of the railway were built in cuttings and tunnels which are lower than the surrounding area, or in low-lying flat areas with limited drainage, making them prone to flooding.
Flood water can wash away the ballast which supports the sleepers making the line unsafe until it is re-laid.
The development of land near the railway can increase the risk of flooding - if the drainage system is inadequate, rain which previously soaked into the ground may run off tarmac and concrete and straight onto the tracks.
When the water level rises above the rails, trains have to reduce their speed to prevent damage to the train. If the track has a live conductor rail, flooding can cause a short circuit.
Point machines and signalling equipment can fail when water enters their housings and may need replacing before services can resume.
How the industry is reducing delays caused by flooding
- When flood warnings from the Environment Agency and Flood Forecasting Centre are received, deploy staff and equipment to at-risk areas so action is taken quickly
- Deploy flood defence systems including modular ridged barriers with a membrane that seals to prevent water getting on the railway, and inflatable barriers which are filled with flood water
- Clear branches and leaves from ditches and culverts on and near the railway
- Building pumping stations in locations which are prone to flooding so we can quickly pump flood water away
- When lines that are at risk of flooding are renewed, the tracks and signalling equipment are raised
- Review planning applications for developments near the railway to make sure they include adequate drainage systems
- Work with the Environment Agency, Flood Forecasting Centre and local authorities to ensure the railway is not negatively affected by the activities of adjoining land owners