A total of 57,000 hectares of agriculture crops have been destroyed, he said.
At least 483 people have died and 15 people are still missing since the floods ravaged Kerala, Chief Minister Pinarayi Vijayan said on Thursday.
Opening the debate at a special one-day session of the Assembly to discuss the disaster, Mr Vijayan said that at the height of the floods, the worst to hit the state in a century, there were 14.50 lakh people in relief camps.
"The latest figure is there are 59,296 people in 305 relief camps. A total of 57,000 hectares of agriculture crops have been destroyed. An approximate estimate of the loss is more than the annual outlay of our state," he said.
The Chief Minister said the Meteorological department gave out adequate warnings regarding the rains but the unprecedented showers led to a deluge.
The predicted rains from August 9 to 15 were 98.5 mm but the state got 352.2 mm, he said.
Hitting hard at the government, senior Congress legislator V.D. Sateeshan, whose constituency Paravur in Ernakulam district was submerged in flood and dam waters, called it "a man-made tragedy".
"This is not a natural calamity, instead a man-made tragedy due to the faulty handling of the dam water management. Dams in the state were overflowing and the primary reason for this tragedy is the way the dam waters were indiscriminately let out," he said.
"Several dams was opened at midnight. The need of the hour is to fix responsibility and find out who all are responsible for this."
Thomas Chandy, a former Minister who represents Kuttanadu in Alappuzha, one of the worst hit districts, asked Vijayan to release the Rs 10,000 that the government had promised as interim relief to every family without delay.
K.M. Mani, a veteran opposition legislator, applauded the rescue efforts but said the tragedy could have been avoided had there been a proper dam management policy.
"Now that the tragedy is over, rehabilitation work has to take a systematic approach," he said.
Mr Mani added that money pouring into building a new Kerala should be collected in a separate account.
"We all know what happened when Ockhi struck and still there has been no proper accounting of the money which is kept in the Chief Minister's Distress Relief Fund. So we should have a separate account."
The session saw a tough stand taken by the CPI-M when it failed to allow two of its legislators, Raju Abraham and Saji Cherian, from speaking in the Assembly while permitting nine other legislators to do so.
According to informed sources, the Chief Minister was cut up with the two MLAs as they had gone public criticizing the rescue operations and also the way the dams were opened.