Fadnavis was talking to reporters after an aerial survey of the flood-ravaged areas which also include Satara and Pune district, along with his cabinet colleagues Chandrakanat Patil, Girish Mahajan and Eknath Shinde.
He said that "the situation is very grim, and a national calamity would be declared in the region at the appropriate time".
While 14 deaths are recorded in Kolhapur due to the rains in the past few days, at least 12 persons drowned when a rescue boat capsized in Brahamnal village of Sangli this morning.
Earlier Konkan Divisional Commissioner Deepak Mhaiskar said nine people were killed when the boat carrying around 30 villagers lost balance and overturned leading to the tragedy. While 15 people were saved, a search is on to trace others still missing in the flood waters.
The Chief Minister said that warlike rescue efforts have been launched with over 10,000 personnel, from 13 National Disaster Response Force teams, one of the State Disaster Response Force, a column of Indian Army, 14 Navy teams, a Coast Guard team and the Air Force and local agencies engaged in rescuing people trapped in the flood waters in the two districts.
Another two Coast Guard teams are on way to Kolhapur on Thursday, five Navy teams and two SDRF teams, while the state has sought five more NDRF teams, Fadnavis said.
He said rescue works are hampered as the water levels are still not going receding in most areas. He spoke with Karnataka Chief Minister B. S. Yediyurappa for the third time this week and the latter has agreed to release 500,000 cusecs water from the Almatty Dam which will bring relief to waterlogging in Sangli.
So far, over 1.35 lakh people have been rescued and shifted to safer locations in the affected regions and thousands more still continued to remain marooned without food, drinking water, medicines, electricity, and other essentials.
People were also saved from several government and private hospitals where they were trapped due to water all around.
Fadnavis said medicals teams are ready in Mumbai and will be dispatched to the affected areas as demanded by the local authorities as incessant rains have submerged large areas of land, fields, villages, towns and cities, hitting both road and rail traffic badly.
Efforts are on to clear the Pune-Bengaluru Highway to enable quicker movement of relief supplies and manpower to the regions, he added.
( With inputs from IANS )