Bangkok, Thailand (CNN) -- The death toll from Thailand's worst flooding in half a century reached 506 Sunday as floodwaters inched southward toward downtown Bangkok, the interior ministry said.
With evacuations already affecting at least 11 of Bangkok's 50 districts, its governor, Sukhumbhand Paribatra, on Sunday expressed fresh concerns about even-worse flooding due to malfunctions at 14 flood gates in western Bangkok, the state-run MCOT news agency reported.
Moreover, the city's flood relief operations headquarters (which has already been moved once) is now surrounded by water. Even so, Prime Minister Yingluck Shinawatra said that there are no plans currently to move it, according to MCOT.
The water continued to rise further Sunday around the city. Hints of seeming normalcy -- like all 18 subway stations operating normally, despite some station entrances being closed -- clashed against continuing concerns about the situation and the government's ability to handle it.
"I don't know what the government is doing," said resident Chaiwat Rattanawitthayapol, as he shopped for water pumps and sandbags to protect his home. "They promised that water would be diverted to the east and west. ... Why is water coming closer and closer to (the) central part? I don't see any improvement."
At the sprawling 27-acre Chatuchak Weekend Market, only about 10% of the booths were open. Some merchants reduced prices to draw shoppers.
"There are a lot less people (who came) today. ... People are afraid of flooding," one shop owner told CNN.
Meanwhile, Arun Sricharoon, the market's director, kept a close eye on the approaching waters. A 2-foot (60-centimeter) wall around the market should help prevent flooding, he said.
"I think the wall is still able to handle the flood," he said. "But if water spills into the market, and if it affects the safety of shop owners, then we will announce the (market's) closure."
Across the country, the flooding -- now in its third month -- has affected 25 of Thailand's 77 provinces.
A Thailand Disaster and Mitigation Department report, issued Sunday and reported by MCOT, estimated about 3.1 million people have been affected and 4 million acres of farmland have been damaged. Moreover, the department said two people are believed missing and about 75 highways have closed.
In the provinces of Nakhon Sawan and Ayutthaya, cleanup efforts were under way.
On Sunday, the prime minister visited Nonthaburi, near Bangkok. There, the government provided 100 boats to help transport people and disperse relief supplies after requests by local officials, according to MCOT.
Despite public criticism of the government's overall response, Yingluck said she would not shake up her Cabinet -- in the short-term, at least. She explained that the focus first is to address the situation, with a full evaluation and possible shuffling to be done after the crisis abates, reported MCOT.
Floods are an annual occurrence in the country but have been particularly acute this year, and some residents and analysts have criticized the government's response.
"Now the government is sending a mixed signal that the situation is fine, but the truth is it the situation far from over," political analyst Supong Limtanakul told CNN. "It is a slow suffocating death of (the) Bangkok business area."
The city's main airport and two large industrial sites are also at risk, Supong said.
Supong said the government did not have enough resources to deal with floodwaters, noting that officials had recently asked the private sector for water pumps to help drain water out of Bangkok.
Bangkok's central business district was still dry, but other parts of the bustling metropolis of 12 million people were flooded.
Paribatra, Bangkok's governor, told MCOT that it may take up to two weeks to drain water out of Bangkok's main roads, and months to drain water from smaller roads.