The group overseeing the fundraiser for the fire-damaged Dunston Staiths has been left "overwhelmed" by the community response as the total nears £6,000.
The blaze broke out in the early hours of Saturday morning and destroyed the walkway of the 126-year-old former coal transporter. It is believed to have been started deliberately.
Volunteers at the Tyne And Wear Building Preservation Trust said the incident has caused an estimated £300,000 worth of damage to the Grade II-listed site.
A fundraising campaign has since been launched in a bid to generate £25,000, which will go towards the repair work and almost £5,900 has been raised so far.
A statement on the fundraising page from Friends of the Staiths, which has organised the campaign, said: "Early on Saturday morning 16 May, Dunston Staiths suffered a major arson attack that has severely damaged 5 frames of the precious structure.
"This campaign (launched by Staiths Friends, volunteers who support the restoration project) is to raise funds - firstly to carry out works to make the structure safe, increase security and then to restore public access.
"Seasonal opening has been delayed this year due to coronavirus. We still hope to hold our well loved Staiths Food Market and Dog Show, subject to public health considerations, in the summer.
"Fundraising also continues to enable repairs, including installing the new deck planks that funds were raised for in 2019.
"We have been overwhelmed by the public response to this disaster, reminding us all of the importance of our heritage to all our futures."
Donations to the fundraising campaign can be made here.
Following the fire, detective inspector Andy Gimza of Northumbria Police said: “This incident sadly comes after months of fundraising to restore the structure following a fire in 2019.
"At present, we’re treating this as a deliberate act of vandalism, so a criminal investigation has been launched."
Anyone with information is asked by Northumbria Police to visit the ‘Report an Incident’ section of their website, quoting reference number 107 of May 16 or call Crimestoppers anonymously on 0800 555 111.
