There's still a lot of trash on a road that leads to a public dumping site and a green waste recycler, but it's getting better, say some Kailua residents.

However, out in central O'ahu, an environmental activist said the problem is getting worse because some transfer stations are so overwhelmed by legal dumping that they end up closing early. He suspects that's a reason people decide to unload trash from their vehicles on the side of the road.

So many different agencies deal with the issue that it's difficult to get more than a snapshot of the problem, but it's clear it's not going away.

Shannon Wood, of the Windward Ahupuaa Alliance, said there has been significant improvement along Kapa'a Quarry Road, thanks to regular bulky item pickup and lengthened dumping hours at the convenience centers. Still, she said the problem will persist until laws are toughened and enforced and public dumping facilities are made more accessible.

"You have to make it exceptionally easy for people to do the right thing and excruciatingly painful to do things wrong," she said.

Both the city and state have been trying to crack down on small businesses — hauling companies and construction companies, for instance — that dump illegally to avoid paying the tipping fee charged to commercial enterprises.

Wood said that these commercial haulers are responsible for the largest amount of illegal dumping.

However, frustrated residents who attempt to dump legally also end up discarding items on the side of the road because they arrive too late to use the city's transfer stations, even though the hours were extended from 4:30 to 6 p.m. a few years ago.

Wood said that's helped, but she still sees a lot of illegally dumped green waste because the private recycler keeps shorter hours than the city dump.

Carroll Cox, president of EnviroWatch, Inc., agrees that discarding trash needs to be easier.

Over the past few months, he's noticed that some of the city's convenience centers have filled up before closing time. "They're overwhelmed. The cans are backed up and they don't have enough drivers" to take the garbage to the Waimanalo Gulch Landfill, he said.

If someone is turned away with a load of trash, "What happens?" Cox asked. "Does he go back and take it off and wait for the next morning, when even then it's a crap shoot whether you'll be able to dump the next day?"

The Waipahu Convenience Center in particular has had capacity issues, but the city Department of Environmental Services reports that the number of complaints has dropped since January, when 10 new Rolloff trucks were leased.

Steve Chang, the Department of Health's Solid and Hazardous Waste Branch chief, said that the complaints to his department have remained consistent at about 300 a year.

The complaints range from debris accumulating on a neighbor's yard to people turning public land into their own personal dumping ground.

"We do respond," said Chang, who said that it's hard to catch people in the act. "Unfortunately, a lot of times we place the burden on the property owners."

Remote areas often have chronic problems, such as a gulch in Waipahu where the city has just embarked on a cleanup of appliances, shopping carts, old tires and other items that will take a month to remove, according to city officials.

Deborah Ward, spokeswoman for the Department of Land and Natural Resources, said that recently the state took steps to track down the owner of a vehicle that had run off a cliff and had the insurance company lift it out. No sooner was it gone, than another car appeared in the same place.

Cox said that he thinks the problem is more blatant and brazen now than it's ever been. "All over, I'm seeing it," he said. "If I go out to Kunia, I'm seeing a large amount there, in the same usual sites, but it seems to be larger volumes and larger quantities and a wider range of materials."

Reach Treena Shapiro at tshapiro@honoluluadvertiser.com.