First they swept and cleared debris, now soldiers deployed to the flood-affected northern rivers region are rolling up their sleeves to donate blood.

After the main donation centre in Lismore was damaged by floodwater and closed, Lifeblood opened a pop-up donor centre in Ballina.

Lifeblood Lismore centre services officer Helen Sager said despite the destruction in the community the need for blood remained.

“We’re grateful to have the team come down to donate their blood so lovingly for us,” Ms Sager said.

“They were cleaning the streets, now they’re going to save some lives.

“Lots of people have lost everything but lots of people still need blood.”

Groups of soldiers waited in the makeshift donor centre next to the community library.

Among them was first-time donor Sergeant Nicole Hall, from 1 Armoured Regiment.

She said it was a good feeling knowing her donation could help save up to three people.

The benefits of her visit extended beyond the donation. It was also a chance to connect with people and hear their stories.

“Talking to the lady who took my blood, her home had been affected by the flood water and it was up to roof height,” Sergeant Hall said. “It hits hard when you find out all these stories.”

Arriving in groups every 15 minutes, the soldiers queued for their turn to give blood while others sat and waited until they were clear to return to work.

Against the back wall of the donor centre was a whiteboard with a simple message: ‘Thank you for your gift of life.’

“The floods were a nightmare for everyone,” said Ms Hager, who had friends and family who lost everything.

“To see complete strangers come in and help with machinery, helicopters and manpower is hard to comprehend; we’re so grateful.”

Ms Hager said mobile collections would continue around Northern NSW until the Lismore Lifeblood centre was operational, which could take months.