Overflowing water courses have so far mostly damaged farms and summer cottages.
The total land area under water is said to be difficult to estimate. Experts from the National Land Survey will be mapping the extent of flooding over the next few days.
Floods expert Juha-Pekka Triipponen from the local Centre for Economic Development, Transport and the Environment said that water levels in the Merikarvianjoki River likely peaked on Thursday. Levels nearly peaked also in Lake Isojärvi, though water in Lake Poosjärvi may still rise.
Regional rescue services officials say there is no need for emergency action, but they have urged local governments and local residents to take precautionary measures such as reinforcing dikes in areas where waters are still rising.