Calls are growing for Whanganui to review its open slather approach to freedom camping.

Photo: RNZ / Robin Martin

Campgrounds say they are missing out on valuable revenue while some residents say freedom camping in the city has got out of hand and popular sites are becoming overwhelmed.

Whanganui promotes itself as a motorhome-friendly city and does not have a freedom camping bylaw.

Instead, it encourages freedom campers to use nine designated areas.

Six are promoted as suitable for self-contained vehicles while the other three welcomes everyone.

There is no restriction on how long campers can stay.

The most popular site is alongside the Whanganui River on Anzac Parade.

It attracts up to 45 vans a night and the council recently installed a dump station, toilets and water fountain there as part of an almost $300,000 upgrade of public facilities.

Photo: RNZ / Robin Martin

That gets under the skin of Ben Kay, co-owner of the Whanganui River Top Ten Holiday Park which is across the awa in Aramoho.

"As many people as you like can stay there - tents, campervans, caravans - and you can stay as long as you like. You can come and live here free of charge and the Whanganui taxpayer will pick up the bill."

Kay said he essentially now paid $1800 a month in rent and $4000 a quarter in rates to a direct competitor.

"It's a little frustrating every couple of years ... we lease this land ... so the council put the bill up for us yet they opened up a brand new freedom camping spot on the side of the river in direct competition with us a couple of years ago and you can come down there and stay as long as you like completely free of charge and the council have put in a nice new toilet block for you as well."

Photo: RNZ / Robin Martin

Gary Rainey is the co-owner of Anndion Lodge which is directly across the road from the Anzac Parade camp.

He said it had taken off.

"I wasn't aware of people just sort of parking up there until we saw public toilets arrive. We knew nothing about [it] until the toilet block arrived and then almost overnight it was full and it's been full just about every night.

"It's just incredible. I don't know what their advertising is but I need some of that."

Rainey said his business had not been too adversely affected but his biggest gripe was when tents were pitched all along the riverbank spoiling views for his paying guests.

Gary Daignault, who owns a private home next door to Rainey's Anndion Lodge, noticed more campers too.

"There are days when look out across and go 'holy cow there are quite a few over there'," he said.

"I think there worst part is when they start to get comfortable over there and we start to see their laundry hanging in the trees."

Photo: RNZ / Robin Martin

Across in town in Castlecliff, Karla Swainson owns the Whanganui Seaside Holiday Park with husband Colin.

She said they had invested $200,000 in the business over the past two years using local contractors and they were getting burnt by freedom campers too.

"Every motorhome, as an average, they'd be taking about $30 out a night per van so you times that by ... you know there's usually 20 or 30 vans out there in any one night ... so you times that by 30 and by 52 weeks of the year or whatever and you've got a lot of money that's coming out of communities."

She said Whanganui should clamp down on the practice.

"Freedom camping is a good thing for Kiwis but it just gets exploited basically by tourists and a lot of councils believe they are bringing money into the cities and towns but as a whole, they don't. They are not massive spenders that's why they are travelling the countryside for free."

Photo: RNZ / Robin Martin

Whanganui mayor Hamish McDouall said a ban on freedom camping was not likely.

"We're not in competition with the campgrounds and we're not going to ban freedom campers because we do want to encourage freedom campers here and it is obviously working and essentially we will promote Whanganui."

McDouall said the Seaside Holiday Park was still the number one destination for motorhomes visiting Whanganui.

But conceded the council may have to look at restricting the time freedom campers were allowed to stay in one spot.

"A stay limit, absolutely, because it's not something that has been raised before. A lot of people are transitioning through Whanganui to somewhere else so staying for longer than three days is not something we've had reported to us so yeah so absolutely we'll look at that."

The council had hired a freedom camping ambassador this summer to count camper numbers and monitor behaviour and how long they stayed.

This information would be used to decide whether a bylaw was required or not.