The increasing sight of rats in the 77-year-old Tiong Bahru estate has become a cause of alarm for residents, who say that the rising number of eateries there is one reason for the problem.
Over the last six months, rodents have been seen scurrying in broad daylight, with some even running into ground floor units of homes and shops.
"There's definitely a growing presence of rats along Tiong Poh Road and Seng Poh Road. I will spot one almost every time I walk there," said teacher Fred Ong, 30, adding that some of these pests were "huge".
"It's never been this bad," said Madam Yee Kwai Wing.
The 76-year-old, who has lived there since 1986, spots two or three rats outside her ground floor flat at 73 Eng Watt Street almost every day.
Unsealed gaps along drains which run along some ground floor units provide perfect hiding and nesting spots.
"They find their way out from the many gaps in our drains, pipes and holes in the ground, to eat the garbage residents and restaurants throw away," she explained.
Minimart owner Rodney Goh believes the problem is made worse by the lack of a centralised rubbish chute system at the estate.
Instead, rubbish bins line the backs of the old blocks, some of which were built by the Singapore Improvement Trust in the 1930s.
As not all residents dispose of their refuse properly, the waste food only encourages rats to set up home, he added.
"Sometimes when it rains, the drains flood and the rats run in through our shop's front entrance," said the 58-year-old.
The National Environment Agency (NEA) told The Straits Times that it found 26 rat burrows during its latest inspection last Wednesday.
This was after the agency found 16 burrows, which were subsequently treated and sealed by the Tanjong Pagar Town Council's (TPTC) pest control team, in common areas of the estate during a routine check on June 27.
NEA said that the town council has been advised to "intensify surveillance and treatment to reduce the rat population".
Last week, it was reported that more than 10 rodent nests were found in the nearby Bukit Merah estate, which also comes under the TPTC.
Rodents typically nest and burrow in the ground, under buildings, and in rubbish and other types of litter. In 2010, the NEA found 1,687 areas with rats, three times more than the 443 the year before. The Norway rat species makes up 90 per cent of the rodents in Singapore.
"The number of rats per burrow really depends on the time they are left alone to breed. Over time, they can form an underground network," said technical specialist Hadi Hanafi, 31, from Maximum Pest Management.
Tanjong Pagar MP Indranee Rajah has asked the town council and grassroots to address the growing rat problem.
"They will be checking on the eateries and adopting measures to control the problem. When dealing with rats we need to find out where the burrows and food sources are."
She added that rubbish should be secured tightly in bins as plastic bags alone do not suffice.
While the NEA said it has taken action against a food operator in Tiong Bahru, other operators in the area were found to be clean, with proper refuse management and food storage.
But it also reminded them to continue making sure that waste food is properly disposed of.
The Orange Thimble cafe in Tiong Bahru hires its own pest control company to ensure that it stays rodent free.
Said its manager Dewihajar Ali, 34: "Our pest control guy comes by at least once a month. He places a certain type of chemical in the drain to make sure the rats stay away.
"We need to be responsible over our garbage and make sure the bags are secured tightly. It will be good if every establishment does its part."