The region has seen a number of devastating floods in the past week
A motorist driving through the flooded Brimstage Road on January 6(Image: Andrew Teebay Liverpool Echo)
Several areas across Merseyside have been affected by flooding in recent days as heavy rain, snow, sleet and hail has hit the region. People in Haydock were particularly badly hit, with homes at the junction of Blackbrook Road and West End Road submerged in feet of filthy water after downpours on New Year’s Eve.
Merseyrail services and flights from Liverpool John Lennon Airport have been cancelled in recent days due to the flooding and snow. The Environment Agency has also issued a number of flood alerts for Merseyside as river levels remain high in some areas following sleet, snow and rain.
Areas most at risk currently include River Alt and other watercourses from Huyton to Hightown including, Kirkby, Fazakerley, Maghull, Formby, Aughton, Sefton and Lunt. Wirral has also seen a number of roads affected by the weather, with the council saying the flooding was “predominately as a result of melting snow”.
The past year saw flooding events in Sefton rise by more than 70%. The most significant event occurred on Bulwer Street, Bootle in September, when heavy rain contributed to a failure in the combined sewer system and resulted in severe flooding – forcing residents from their homes and causing huge damage to the properties.
In light of these incidents, Professor Neil Macdonald from the University of Liverpool’s School of Environmental Science has explained why Merseyside has seen an increase in flooding recently and what the region can do to prepare for future events. He also warned that matters may worsen as sea levels rise in the future.
Professor Macdonald told the ECHO: “There are three main causes or threats of flooding in Merseyside, coastal, fluvial (rivers) and pluvial (surface waters). The causes of flooding in a specific location can be varied, or a result of a combination of factors.
“A changing climate is impacting how we experience heavy precipitation events, whilst we have seen a reduction in snowfall, and expect to see a reduced annual totals in the future, the intensity of individual rainfall events may increase, causing challenges for our drainage systems and waterways.
“We can also expect to see increased sea levels, which may present particular challenges to coastal communities around the coastline of Merseyside, we have already seen the erosion of sand dunes up in Formby, and the threat to communities in north Wirral from future sea level change is already well known.”
As Merseyside’s coastal areas can be particularly badly hit by flooding, Professor Macdonald said a number of changes could be implemented to reduce the risk of this worsening in the future, including alterations to older drainage systems. He explained: “Several areas across Merseyside are susceptible to coastal flooding and these are generally well known, for example the threat to the north Wirral coastline resulting from storms and sea level rise has been well reported, other areas may also be at risk, with some coastal sections protected by sea walls and coastal defences.
Sheep in a flooded field on Brimstage Road. (Pic Andrew Teebay).(Image: Andrew Teebay Liverpool Echo)
“Historically many of the local rivers that drain the city have been integrated into our drainage systems, indeed it was the first such system in the world when designed by James Newlands and construction began in 1848. During heavy rainfall the integrated system can find it challenging to drain all of the water, which can result in surface water flooding, so we need to look at trying to slow the water entering the system or reduce it.
“We can also change the way we cover surfaces, so enabling water to percolate through the surfaces (often known as Sustainable urban Drainage Systems, a common example would be in car parks) rather than running off into drainage systems can help reduce the amount of water entering the drainage system. Increasingly new buildings are employing green roofs, where plants capture and hold some of the rainfall, or soakaways offer opportunities for water to soak into the soil, these need not be expensive solutions.
“In more rural areas where more space may be available, we can enable and encourage waters to spill out of the channel into floodplain areas, giving the system space to store and slow the flow of water.”
Professor Macdonald added: “One of the main challenges facing the region is reducing flood risk, part of this process will be reducing the speed at which waters reach and travel through our drainage system. Historically we have straightened and paved over many of our natural waterways, and in some cases integrated them into our combined drainage systems.
“We need to look at ways of slowing these processes, whilst this is not possible everywhere, there are a range of ways we can do this, even simply having a water butt on downpipes off our roof can help slow the flow.”
Flooding at the junction of Blackbrook Road and West End Road, Haydock, St Helens, January 1 2025
Asked about how flooding could change the face of Merseyside in coming years, Professor Macdonald said: “Whilst we might see a reduction in annual precipitation as a result of climate change across Merseyside, the precipitation that does fall may increase in intensity, therefore our drainage systems will need to transport more water faster. Where they are unable to do this, we may well see more localised flooding.
“One way to reduce this threat is to reduce the speed that the water enters and travels through the drainage system, in rivers this might include re-wiggling, adding vegetation or using other approaches such as Natural Flood Management techniques that slow the water down, at other locations we might try and increase the amount of precipitation that can soak away rather than entering our drainage system. The River Alt catchment is currently benefitting from a £2.1m Natural Flood Management project led by the Mersey Rivers Trust, the largest such project in the recent £25m NFM DEFRA programme.
“This seeks through a range of interventions to slow the flow of waters through the drainage network, often starting on small streams to hold the water back, creating more natural landscapes, or creating spaces for the water to spill out of streams and rivers and be stored, thereby reducing downstream flood risk.”