As many as 7,000 people were taken ill with diarrhoea and other waterborne diseases that also killed at least three in the last 24 hours, according to the health directorate.

The disaster management ministry recorded that 16 more people died in flood-related incidents, bringing the death toll to 489 in three weeks, while unconfirmed reports put the figure at 500, official news agency BSS said.

Residents in Hazaribagh complained of skin diseases blamed on toxic effluent from tanneries, which mixed with stagnated floodwaters.

Water levels in five rivers around the capital went an average of 7 cm down, triggering slight recession of floodwaters from the south and southwestern fringes, but the plight of people on the waterlogged eastern fringe continues.

The Buriganga river still flows 55 cm above the danger mark, Balu 186 cm, Lakkhya 106 cm, Turag 125 cm and Tongi Khal 99 cm, the Flood Forecasting and Warning Centre said.

The army and local volunteers sandbagged 100 points of Dhaka-Narayanganj-Demra (DND) embankment where water gushed through.

About half a million people crammed into flood shelters or were living on rooftops and many more clung to their inundated houses. Traffic tended to keep off Gulshan-1-Tejgaon and Gulshan-1-Mohakhali roads, as filthy water logs two points on both roads.

The Water Development Board, Water and Sewerage Authority and locals are pumping floodwaters and sewage out of many areas by 104 pumps -- an effort that contributed a little to easing the pressure of waterlogging.

Millions of people are without adequate food or clean water, as the floods -- the most devastating since Bangladesh's worst floods of 1998 -- have submerged two-thirds of the country.

Talking to The Daily Star, flood victims who took refuge in flood shelters in 55 wards of the capital asked for more relief and said they were not getting enough.

Non-governmental and sociocultural organisations distributing relief in the capital called on the government to provide more relief.

BSS said at least 1,026 patients contracted diarrhoea in Dhaka and 515 of them were admitted to the ICDDR,B (International Centre for Diarrhoeal Diseases and Research, Bangladesh) alone yesterday.

Swirling waters have also caused billions of dollars of damage to bridges, homes, roads, rail lines, communication links and businesses, Reuters said.

The flood situation in Dhaka, Munshiganj, Narayanganj and Chandpur will improve, the flood forecasting centre said.

The Brahmaputra-Jamuna and the Ganges-Padma continued to fall further and most rivers in the Meghna and the southeastern hill basins were also falling.

The floods in Sylhet, Sunamganj, Moulvibazar, Netrokona, Pabna, Mymensingh, Sirajganj, Manikganj, Tangail, Madaripur, Rajbari, Shariatpur, Gopalganj, Narsingdi, Kishoreganj and Brahmanbaria are likely to improve further, a flood bulletin said.

SCARRED NORTHEAST

Diarrhoea has been spreading with water recession from different upazilas in Sylhet, Sunamganj, Habiganj and Moulvibazar. The situation turned serious in remote areas where most tubewells went under water.

The scarcity of drinking water hit most upazilas. All hospitals in the region saw a rush of diarrhoea patients.

The floods in Muladi, Babuganj and Banaripara upazilas in Barisal and Kotalipara in Gopalganj deteriorated in the last 24 hours.

Seventy-year-old Moslem Bhuiyan starved to death in flood-ravaged Batamara in Muladi upazila early Thursday, raising the death toll to 15 in Barisal.

AFP adds: Food and Disaster Management Minister Kamal Ibne Yusuf said a UN team was to arrive in Dhaka yesterday to assess the damage from the floods that have submerged wide tracts of farmland, villages and cities.

The UN said earlier it would launch an appeal over the next few weeks to provide aid for post-flood rehabilitation.

Experts have said receding floodwater flowing downstream from northern Bangladesh will not be able to drain into the Bay of Bengal because of high tides in the bay until the full moon on Monday.

If there is more rain before the latest floodwaters subside, the Bangladesh Red Crescent Society said, the low-lying nation through which over 50 rivers flow could face a "major humanitarian crisis".

Forecasters said a low-pressure area that threatened to cause heavy rain and more flooding was now moving away from Bangladesh. But Akram Hossain, director of the Meteorological Department, said more heavy rain was forecast for mid-August.

(AFP, Reuters and BSS contributed to this report)