Flood situation in Surat worsened on Wednesday with the water released from Ukai dam on river Tapti paralysing road and rail traffic, even as Army personnel were engaged in rescue operations.
The whole of Surat is now under water, Flood Control sources said.
Water level at many areas rose further due to high tide and full moon day, preventing the river water from entering the sea in the Gulf of Khambat.
Thousands of stranded people have taken shelter on their terraces, or other buildings, waiting to be rescued by the authorities even as Army was trying to evacuate people with the help of boats and helicopters.
Rail traffic is totally paralysed while the National Highway number eight has been closed to vehicular traffic due to flooding, the sources said, adding that six people were killed in last three days due to flooding.
There is severe shortage of clean drinking water, milk and food materials.
Gujarat Chief Minister Narendra Modi, who made an aerial survey of the flood-hit areas on Wednesday, appealed to the Centre to release an immediate interim assistance of Rs 2000 crore to tide over the crisis.