Northumbrian Water is back in court today as it seeks to overturn a ruling in favour of the Water Services Regulation Authority (Ofwat) decision regarding penalties for supply interruptions.
The north east water company filed a judicial review application to the High Court last year to challenge the a regulator decision.
Last year, Ofwat decided to only partially relieve Northumbrian Water from a reduction in prices because it labelled the water company as under-performing in water supply interruptions, which occurred as a result of Storm Arwen.
The water company tried to block this with a judicial review but Mrs Justice Dias dismissed its application.
This ruling confirmed that Ofwat has discretion on whether to relieve a water undertaker from price reduction consequences if it fails to fulfil its water supply commitments in instances of civil emergencies such as extreme weather events.
Now the water company seeks to over turn Mrs Justice Dias decision as it brings its case to the Court of Appeal.
The case will be heard before Lord Justice Peter Jackson, Lord Justice Lewis and Lady Justice Elisabeth Laing over today and tomorrow at court 70.
Elsewhere, Northumbrian Water is one of the many water companies facing a class action in a UK Tribunal over allegations of underreporting pollution incidents and overcharging customers.