As soon as the flood waters receded from Kowhai Park, community workers were in there with gumboots and shovels, clearing away the mud.
Those sentenced to community work have put more than 2000 man hours into cleaning up the park following the June floods, service manager David Francis said.
"We basically came in as soon as we could," he said.
Corrections offered their services to the Wanganui District Council "and they took that up pretty quickly".
The community workers got to work on jobs that could only be done manually, as much of the machinery could not be brought in yet.
"The type of material that was leftover after the floods is quite hard to work in, it's quite gluggy, and lifting a spade full of that was quite difficult."
Supervisor Alex Baumanis said they were "basically" picking up "liquid mud".
Mr Francis said a great deal of the mud had to be cleared away by hand and put into piles for the machinery to pick up.
"It's been really heavily labour-intensive," he said.
An anonymous community worker said the work was "not too bad".
"I've done harder than this," he said.
"It's doing something positive anyway ... my children used to come here when they were young. I used to come here, actually."
The man said he lived nearby, and could see the progress they were making every time he went past.
"I just like it here."
Mr Francis said despite the hard work, many of the workers knew they were doing something positive.
"At the end of the day they know it's for the kids," he said.
"To be fair it's some of the hardest work that our offenders have undertaken, but it's that real sense of giving back to the community.
"If it's weighing this job up against another one, this is the one where they feel they're giving the most back."
Mr Francis said the workers were also developing skills through the clean up work.
Council contracts officer Dave Kerwin said the clean-up process would have been "a lot slower" without the community workers' help.
"It's just been too wet for all the machinery," he said.
Two work parties of up to 10 offenders in each work four days a week on the clean-up.
Mr Francis said they were hoping the park would be reopened by Christmas.