The four-week event took place in the run up to Christmas last year with displays, fireworks and music drawing thousands to the seafront and Roker Park.
Highlights included the Winter Wonderland, a mystical ‘Underwater Kingdom’ projection as well as a 18-metre-high ‘Sunderland sphere’ illuminated dome.
New figures reveal 150,000 people visited Sunderland during the event with 133,000 tickets sold for the Festival of Light itself.
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Around 34% of people attending also were first-time visitors with the average Sunderland resident spending around £30.
Head of events at Sunderland City Council, Victoria French, told the Economic Prosperity Scrutiny Committee this week (Feb 12): “It’s great for the city to have these events and we work a lot with the residents in the area.
“We absolutely recognise for some it’s an inconvenience and we work with them around parking arrangements and access and try and make sure that the event runs as smoothly as possible so as to not put them out of their routines.
“Certainly if you look at this purely from an economic impact, (the Festival of Light) has a really good impact on the city.”
The £8.5milllion city boost factors in spending from Sunderland residents and visitors from the North East and afar.
This included guests from Stockton, Teesside, Yorkshire, Scotland and the south of England.
While research found the event was seen as value for money due to its concessions and offers, the Festival of Light is set for major changes this year.
This includes a move to Mowbray Park between November 21-December 21, the meeting heard, with the potential for revised prices / discounts and a new themed programme of events.
The changes form part of the 2019 events calendar which will be aimed at getting more people to visit the city centre, with new food and music festivals also planned.
Coun Barry Curran praised the move and said events bosses could form a group with residents to discuss concerns about events following the success of a similar model on the seafront.
Committee chairman, Doris MacKnight, also said the move could provide a boost to city centre business from increased christmas shopping.
Events boss Ms French added: “That’s part of the thinking, we know that people from outside of Sunderland are travelling in for this event.
“If we can encourage them to travel in and spend more time in the city centre, to do some shopping and have something to eat and contribute to the economy, we hope that will have a really positive impact.”
Last year, it was revealed that other flagship events in 2018 – such as the Tall Ships Races and the Sunderland Airshow – boosted Sunderland’s economy by nearly £20million.
Ths included the Tall Ships attracting 1.2million people including international guests.
On it’s 30-year anniversary, the Sunderland Airshow also brought in 600,000 visitors over three days.
Chris Binding , Local Democracy Reporting Service