Authorities are shelling out hundreds of thousands of dollars a year to clean up tonnes of rubbish dumped on the sides of Northland highways and local roads.
The NZ Transport Agency's Northland system manager, Jacqui Hori-Hoult, said rubbish dumping is a growing problem.
"We do heaps of rubbish clearing across the Northland network and it's becoming an increasing problem with people littering or dumping domestic and commercial rubbish along the roadside.
"We clear two dump sites and pick up an average 500 black bags of rubbish a month."
Dump sites have included rest areas and shingle dumps on State Highway 10 and SH1 and at the summit of the Brynderwyns on SH1.
Annual costs for NZTA to clean up roadside rubbish on its network from Puhoi to Cape Reinga are estimated at $78,000.
"Chasing rubbish dumpers is not our core business, but we have to clean up after them. And that's a waste of our time and resources. We all have a responsibility to protect our environment and keep it clean."
The agency has to call in extra contractors when it discovers illegal dumping that can't be part of its usual rubbish collecting along the roadsides.
"The time and resources allocated to cleaning up rubbish would be better spent on pothole repairs, vegetation clearance, signs maintenance, repairing wire-ropes and road sweeping."
Hori-Hoult said the dumping takes two forms.
"There's the mess left near towns by people who've been eating fast food and then just dump the leftovers and wrappings out the window.
"And then there are people who appear to load up their household waste - that's everything from broken furniture and bikes to bags of clothes and old food - and toss it at a rest stop or on the side of the road. They leave a disgusting mess and it's not a great impression for our visitors."
She said it is a year-round problem so locals are responsible for some of it but it's worse in summer with holidaymakers who go home but leave their rubbish behind.
Hori-Hoult said the agency has a partnership with Northland councils over prosecuting dumpers.
"If we find names and addresses in the rubbish we'll work with the councils to follow up. Better still, if people can send us vehicle registrations or photos of dumpers in action. We've got their rubbish. We just need eye witness or photographic evidence to confirm the person responsible."
Local councils are also feeling the pinch of the problem.
Whangārei District Council waste and drainage field officer Grant Alsop said in Whangārei the council deals with about 80 jobs a month, varying from a rubbish bag or piece of furniture to large dump sites.
In the 2017/18 financial year, Whangārei District Council spent $123,072 cleaning up fly-tips, and about $200,000 the year before.
Kaipara District Council's costs for illegal dumping in this financial year are looking at about $50,000, which includes around $30,000 to clean up about 60 tonnes of rubbish in a tomo south of Te Kopuru in August.
Chief operating officer and general manager infrastructure Curt Martin said it's disappointing to see this sort of continuing disregard for the environment.
"We are asking the public to be vigilant and if they see anything they suspect as illegal dumping in public land such as parks, reserves, or even spaces off the road, to note the details of the vehicles and inform the council immediately."
The Far North District Council spent $118,065 in the 2017/18 financial year on dealing with illegal rubbish.
A bill to amend the Litter Act to increase the maximum fine for an infringement from $400 to $1000 is at its second reading.