David Hill, city rat remover, walks softly and carries a big stick -- and a small black suitcase. The wooden stick is to plug up the fist-sized tunnels that rodents dig in the soil for shelter; the suitcase is for the rats.

One recent chilly afternoon, Hill's daily rounds took him to a place he knows all too well, a ramshackle alley behind the 700 block of Hobart Place NW in Columbia Heights. Someone had set a bulky garbage bag on a back deck, and nearby sat three uncovered, filled-to-the-brim trash containers. Hill spotted rat tracks in the snow leading behind a chain-link fence. A few feet away he found a burrow.

Hill reached into his suitcase and pulled out a hand-held contraption resembling a power drill that he calls a duster. He crouched down and placed the tip into the small hole, injecting a powder that coated the inside of the burrow. The powder is what he likes to call a toxicant. It sticks to the rodents and they ingest it when they groom. After plugging up the hole with newspaper, Hill searched for more tunnels.

On the opposite side of the alley, a well-fed rat scurried along a brick wall and vanished around a corner. Neither surprised nor discouraged, Hill is just one of many soldiers on the frontlines of the District's ongoing yet little-noticed war on the rat. From pest control inspectors like Hill who hunt their prey in alleyways to enforcement agents who hand out $1,000 tickets for improperly contained trash, the city has abandoned its laissez-faire attitude toward neighborhood rat problems and is taking a more aggressive approach.

The city's rodent control program, run by the D.C. Department of Health with a budget of $1.6 million and 30 full-time employees, has made significant strides in reducing the rat population, District officials said. In fiscal year 2002, there were 2,659 rodent complaints to the D.C. government. In 1998, the number hit 4,643.

Last year, workers inspected 10,600 commercial and residential premises for rodent activity. Employees such as Hill treated for rodents 2,700 times and enforcement agents issued roughly 650 tickets for rodent-related infractions.

"We're getting ahead of the battle," said Theodore J. Gordon, senior deputy director for environmental health science and regulation for the Department of Health. "It was ahead of us for a while."

But city officials admit the District has a long way to go. For years, rats in the city have roamed as they pleased as city government focused on what it considered more pressing concerns. The rat infestation became a constant gripe of residents, and in 1993 a D.C. Department of Public Works official estimated there were two rats for every person in the city. From 1995 to 1999, rat-related complaints jumped 20 percent.

"When we were facing hard economic times, there were competing priorities," said Gordon, who years ago dealt with rats for health departments in Cleveland and Newark.

But Mayor Anthony A. Williams (D), no friend of the rodent, revived efforts to tackle the rat problem. In April 1999, Williams addressed 250 community leaders, rat experts and city officials at the District's "Rat Summit." There, the mayor said winning the war on rats was essential for the District to reestablish its reputation as a desirable place to live, and vowed an intense rat extermination program.

One of the first administrative steps city leaders took following the summit was to transfer responsibility for the rat issue from the Department of Public Works to the Department of Health, a suggestion by Bruce A. Colvin, a national rodent-control expert.

Now, led by the health department's Bureau of Community Hygiene, which was created in 2001, rodents are something of a city priority. On any given day, about 20 health department workers scour the city conducting abatement work as Hill did recently, checking for sanitation violations or doing educational outreach, city officials said. In addition, health inspectors of restaurants, hospitals and child-care facilities have been trained to conduct inspections for rodents.

Yet even with increased manpower and resources, Gordon said the city cannot clean up the rats without help. "This is a partnership between us, the business community and the residential community," Gordon said.

He and other health officials said residents and businesses can take several steps to help control the city's rodent population, including storing garbage in metal or heavy plastic containers with tight lids, removing weeds and debris near buildings, sweeping up food and trash outside and storing materials such as lumber and boxes on racks. Areas of the city that have the most trouble with rodents are those with older infrastructure, city officials said, such as Georgetown, parts of Adams Morgan, Trinidad and Capitol Hill.

Properly storing trash is more than just a tip from city government to rob rodents' of a food source -- failure to do so can result in a ticket from the health department's code enforcement staff. But, said Mark A. Greenleaf, chief of the Bureau of Community Hygiene, "This isn't about writing tickets." Instead, he said, "We want compliance."

The tickets to push for that compliance, though, range from $50 for homeowners to $1,000 for commercial establishments, and the fines go up for repeat violations. Those who receive tickets can dispute them, and each month about 50 new rodent-related cases arrive at the city's Office of Adjudication and Hearings.

Paul Klein, chief administrative law judge, said that he has seen a decrease in the last six months in the severity of violations, which are heard in a fifth-floor hearing room of a Northeast D.C. building. Reports of 10-foot-high stacks of garbage bags are now the exception, not the rule, Klein said.

Hill handles the rats, not the enforcement. He has done pest control for more than a decade, and can spot rat droppings, rat tracks and tiny burrows with a sharp eye. The winter months are harsh on rats, when their breeding is minimal and their natural food sources such as seeds and insects harder to find.

But Hill keeps at it.

Making his rounds recently, he stopped at Eastern Market, and a quick check turned up no burrows in public spaces. He adjusted his hat. It said DOH on the front. The O had a slash in the middle, with a rat peeking out from inside.

"If you don't have this on," he said, "you're not in uniform."

Rats gnawed a hole in this trash can in the 700 block of Hobart Place NW. The city once was home to two rats per person.Inspector David Hill dusts a rathole with poison in the 700 block of Hobart Place NW. Complaints about rats are down.David Hill, a Health Department pest control inspector, looks for ratholes near Eastern Market in Southeast. Hill's job is to exterminate rats while others handle enforcement.The familiar circle/slash of modern don't-do's adorns David Hill's hat.