MAY 2009

When rats attack: Vector control

Where there’s waste, there’s vectors – critters like rats, mosquitoes and birds that are both a nuisance and a health hazard. Minimizing their presence and reducing vector populations are the goals of the various jurisdictions involved from collection points on the streets to the dumping of trash into landfills.

New York City (NYC) takes vector control very seriously, especially when it comes to rats. The city’s main line of defense is dealing with rats at the collection point. NYC informs citizens and businesses how they should properly put out their trash, the necessary steps to prevent vector infestations and how to deal with infestations.

Some of the city’s anti-rat programs include Property Level Rodent Control, Rodent Indexing, a Citywide Rodent Taskforce and the Rat Control Academy.

Bobby Corrigan, an exterminator who teaches courses at the Academy noted, “We don’t have rat infestations unless there’s major food available. When people say ‘how do I get rid of rats,’ the first thing I always say is, ‘tell me what they’re eating.’ I don’t say, ‘Oh, here’s the poison.’”

Harry Nespoli, president of the Uniformed Sanitationmen’s Association IBT Local 831, knows firsthand the situation of rat infestations in NYC, having spent his early years on the streets working with the city’s Department of Sanitation.

Nespoli applauds the city’s efforts to control vectors and protect sanitation workers. “I saw the city under the gun when the rats just totally had control and right now I don’t believe that is happening,” he said. “It is because of the tough restrictions that city hall is mandating on the public and the private companies to make sure that this stuff is picked up and picked up on a regular basis.

“We’re at our highest point right now with the cleanest streets that we ever had,” he added. “The mayor takes pride in city streets because that is what keeps the rats away. The fact that you don’t have baskets overflowing and have clean sweeping teams that are responsible to clean blocks and ratings on all 59 districts of the city is making a difference.”

Nespoli said that the growing use of trash containers is helping to seriously eliminate food sources for rats, be it on the curb or in alleys.

Along with citizens, the city depends on sanitation workers to be the eyes and ears in terms of reporting vector infestations.

“Our workers are concerned about rats and where they come in contact with people. They report whatever they see,” he said.

While only a few workers have actually been bitten, coming into contact with rats is not pleasant and Nespoli recalls an incident when a rat crawled into the heavy rain gear worn by one worker, which severely startled the employee. Nespoli also recalls situations when rats jumped out of the hopper in the truck, which was very disconcerting.

He credits worker safety to improved vector controls and to workers who move rapidly when collecting trash, wear heavy gloves and take appropriate measures such as kicking cans and bags to check for rats.

NYC sanitation workers collect residential trash and recyclables, while the private sector collects the non-residential sector trash. Since the landfill on Staten Island closed, the city no longer operates waste transfer stations. The private sector also operates MRFs. City inspectors are just as rigorous about how the non-residential sector puts out its trash and maintains its properties.

Sanitation workers who deliver trash to transfer stations are told to report situations where rats are found at these facilities.

He added that vermin prefer solid waste to recyclables and that New Yorkers are recycling in greater numbers and that they are cleaning these items prior to putting them out for collection.

Nespoli stresses that sanitation services are essential and noted that the sanitation department was founded to prevent diseases caused by solid waste.

“We have a responsibility to the taxpayers,” he said. “It’s important and I try to carry that over to my workforce – they are keeping everyone safe from diseases.”

Ed Repa, director of environmental programs with the National Solid Wastes Management Association, said the principal areas where vectors can occur are at the solid waste collection point and landfills – areas where food and water are available.

In terms of landfills, he said that daily six-inch coverings of earth is an effective deterrent to vectors and that in terms of mammals, rats are of primary concern. Birds, mosquitoes and flies are also a concern due to food available at the surface level and the availability of water.

Part of the process is to compact the new waste with steel-wheeled landfill compactors that tear open plastic bags and increase the density of the waste.

“Something in there is probably not going to live very long when you have a big blade spreading the waste and a 100,000 ton-plus vehicle running over the garbage,” said Repa. “I can only speak for the companies I know of – they do a good job. There are often people who live near landfills. Companies that want to keep their permits and get them renewed, which in a lot of places they have to do it on an annual basis, try to be as good a neighbor as they can be. We don’t want to have problems at our landfills.”

Landfill inspectors play a key role in vector control, and according to Repa, they take complaints very seriously.

Landfill operators employ a variety of rat control techniques, including traps and other methods to ensure problems do not occur.

Eliminating standing water at landfills is a key factor in vector control. Rules and regulations are strict about eliminating water sources. Repa said solid waste is naturally wet and rainfall can create surface water pools.

Sound devices with the cries of hawks are employed to keep birds away. Daily cover helps to bury trash and removes an open food source for them. Pyrotechnics are also employed. Gulls, said Repa, because they are a migratory species, are protected federally and cannot be killed unless special permits are issued. This applies to other birds as well.

“New techniques and rules basically prevent landfill operators from making their facilities attractive to animals,” he said, adding that when new regulations and rules are put forward for discussion, facility owners and operators want to work with government at all levels to draw up regulations that are not “onerous,” but ensure that effective solutions are implemented that protect human health and the environment.

“We have,” he said, “under our Resource Conservation and Recovery Act (RCRA), a federal rule that sets standards for landfills. It is very prescriptive and says that you have to control vectors, surface water run-on and run-off and liners.”

Vector infestation at waste transfer stations and MRFs, said Repa, is not a major problem due to quick pickups at transfer stations and at MRFs where very little material is left on the ground by the end of the day.

“We find that rats come from a bin or someone’s garbage, which is dumped into a bin and end up in somebody’s facility,” said Repa. “Some people don’t close the top down or overfill the bins.”

But he noted that the situation is improving due to the growing use of containers by the residential and non-residential sector and the use of trucks designed to pick up bins and deposit the material directly into the truck.

“Most commercial buildings have a container that can be picked up by front-end loading garbage trucks,” said Repa, who noted that when there is lack of standardization on the residential front, people purchase a wide variety of containers and cans, some of which may not be effective due to poorly fitting covers that can be opened by animals. “We have a variety of containers that will keep the rats out for the most part, but if they are sitting in the back alley and people are putting trash into them on a daily basis, the smell may attract other animals.”