Opening the Foss Flood Barrier on Boxing Day ‘was right decision’ – official report

The Foss Barrier in December 2015. Photograph: Richard McDougall
12 May 2016 @ 1.55 pm
| News

A report into the failure of York’s Foss Barrier pumping station has concluded that experts were right to raise it on Boxing Day.

More than 600 homes and businesses were hit by the floods that night. But an independent report has found that raising Foss Barrier

prevented even more widespread flooding; and delayed the peak water levels on the River Foss by some 18 hours.


Had the gate remained in the lowered position, water would have built up behind the gate causing the water levels in the Foss to be higher, putting more properties at risk of flooding.

Other findings by the consultants CH2M include:

  • the peak flow in the Foss on 26 December was extreme, equating to an event with a one in 200 chance of happening in any given year
  • all eight pumps at the Foss Barrier were working that day at full capacity but the water levels in the Foss continued to rise, by approximately 140mm an hour.

Flood water entered the building

A Chinook helicopter hovers above Castle Mills Bridge in York as he delivers parts to repair the Foss barrier which failed causing widespread flooding in the city.Pic : Nigel Holland
A Chinook helicopter hovers above Castle Mills Bridge in York as he delivers parts to repair the Foss barrier which failed causing widespread flooding in the city.Pic : Nigel Holland

Environment Agency staff opened the barrier after water entered the building, forcing them to turn off the electricity supply and the pumps.

The report found that a build up of water in the barrier’s underground service tunnel, combined with water flowing through the drainage system, filled the service tunnel. Water then came through the floor inside the pumping station building.

Most of this water entered the building via a leaking construction joint and an access cover which had been opened to pump water out of the service tunnel.

Public exhibition

Residents have the opportunity to find out more about the work the Environment Agency is planning for York, the upgrade of the Foss Barrier and the independent report, at a public exhibition

Hotel 53, Piccadilly, York

Fri May 20 and Sat May 21

The report makes a number of recommendations to minimise the risk of water entering the facility in future.

The Foss Barrier has been fully operational since the end of December. A £17 million upgrade is now underway which will address all the recommendations made in the report.

This includes addressing water leaks in the service tunnel and new pumps with an increased capacity which will be installed by winter 2016.

By the end of 2017 the pumping station will have been raised to ensure the barrier is more resilient in the long term.

Never prevent flooding

The floods in York last December. Photograph: Nigel Holland
The floods in York last December. Photograph: Nigel Holland

Chief Executive of the Environment Agency Sir James Bevan said:

I was in York in the immediate aftermath of the Boxing Day floods. I know that every house and business flooded is a personal tragedy.

We can never prevent all flooding, but we can and will do everything we can to help reduce the risk to householders and businesses.

I welcome this report, which will help us make the Foss Barrier even more resilient in future to extreme floods and greater flows on the River Foss. The upgrade work, which began in April, will see the pump capacity increase, providing a higher standard of protection for local people.

Work on the Foss Barrier is just one component of a wider programme of work, following the Government’s announcement of £45 million for York.

We are taking a catchment wide approach to improve flood resilience in the city, looking at how we can slow the flow in the upper reaches of the Ouse and Foss catchments as well as new flood defences.

Traumatic time

Rachael Maskell shows Labour leader Jeremy Corbyn the aftermath of the York floods in December
Rachael Maskell shows Labour leader Jeremy Corbyn the aftermath of the York floods in December

York Central MP Rachael Maskell welcomed the report.

With new pumps the Foss Barrier will have a pumping capacity of near to 50T/Sec of water, which is a vast improvement on the current 30T/sec when all the pumps are in operation, as they were on Boxing Day.

The power sources and controls for the upgraded Foss Barrier will be raised under the new design for the building and this will mean the risks of flooding are greatly reduced.

Ms Maskell said questions remain “over the maintenance schedules of the barrier and whether the right tests were applied to the building structure to ensure it could cope with the levels of water pressure experienced on Boxing Day”.

She said:

It is vital that the £17m upgrade ensures that the Foss Barrier is fully functional should future river levels rise as they did last December.

People across the city have had a traumatic time over the past five months. Many had their homes and businesses destroyed and had to deal with a great deal of upheaval.

They also lost many of their personal belongings.

The work continues to rebuild the city, which has shown an incredible community response to the disaster.

Knowing that the Environment Agency will fully implement the report’s recommendations is a positive step forward, as everyone in York deserves the peace of mind to know that when defences are in place, they will do their job.

Attention now turns to the City of York Council review into the operations that surrounded the disaster.

“Everyone I speak to wants to ensure their personal experience is considered as part of the investigation,” Ms Maskell said.