A Gisborne resident has told RNZ she was shocked to see the build-up of rubbish on the ground during Rhythm and Vines.
The popular festival took place between 29 and 31 December at Waiohika Estate, near the East Coast city.
A video has emerged online of rubbish built up along a fence at the event's entrance.
Hayley Maxwell - who took the video - said she was dropping off her daughter on day two of the festival when she saw the rubbish.
"I was just shocked to see when we entered the event itself from the entrance, lined up along the fence line was just a whole pile of rubbish."
Maxwell said anyone who was a proud caretaker of property or land would have been quite taken back by it.
"If we've got visitors coming into Gisborne, I would hate to leave that impression that they think that Gisborne is a place you can come to and just dump rubbish everywhere and it's fine."
She said she understood that groups picked up the rubbish after the event, but believed there should be better management of it during the festival.
"Maybe we need signage, maybe we need to have fines, and be quite strict about it too, because I think there was too much of a lax attitude."
Maxwell said she did think it was an awesome event, but it was important to raise awareness around this issue.
Rhythm and Vines organisers said they could not speak specifically to how rubbish was managed during the event until a full debrief was completed.
They said Thursday was the final day of the post festival clean-up, which can take up to four or five days.
They said there was a crew of 40 waste teams doing the final clean-up, and they were working closely with iwi and the local council.
"As per our yearly process, a thorough post-festival clean-up is being conducted. The main road connecting Gisborne to Waiohika Estate is being surveyed and cleared of all rubbish to leave the area in the best condition possible.
"We continue to work with suppliers, sponsors, [the Department of Conservation] and local iwi to reduce the impact of the festival on the environment. The festival is a single-use plastic-free event, approximately 90 percent of rubbish produced is recyclable and our Bookatent system has reduced landfill waste by over 30 tonnes."
Gisborne mayor Rehette Stoltz said she would not want to put down the whole event due to a minority of people's behaviour.
"I have seen those videos where people dump rubbish, but I also want us to be realistic - with any huge festival, you will have a small group of people that don't respect the rules."
Stoltz said she understood Rhythm and Vines organisers were well prepared to leave the area in the same shape or better than the way they found it.