Officials from the Finnish Transport Agency moved on Thursday to shore up flood-proofing measures along the Turku motorway in Espoo, just west of Helsinki.
The operation focused on the Kirkkojärvi area, where construction work is underway, causing contractors to close one lane of the highway in both directions.
The reinforcement work began with the help of Finnish Defence Forces during the worst of morning rush hour traffic on Thursday.
"Around 30 people from the Defence Forces are assisting in the construction work and we will also get sand bags from them," Transport Agency official Mika Jaatinen said on Thursday.
According to Jaatinen, commuters should be sure to leave earlier than usual to avoid the bottleneck caused by the lane blockages and should also consider alternative routes to work.
More rain in forecast
Jaatinen said that flood waters had been kept in check; however he noted that with more rain in the forecast, water levels could continue to rise.
"The flooding will peak around Friday to Saturday," he predicted.
The transport agency official said that he was hopeful that the levees would hold and that it would not be necessary to close the motorway altogether. In the event that the levees fail, traffic would have to be redirected towards Ring Road 3.
"The road network through Espoon keskus [Espoo centre] cannot accommodate that kind of traffic; people will have to get to Helsinki via Ring Road 3," he explained.
On Friday morning however, the flood barriers appeared to have done their job, prompting Jaatinen to declare an interim victory.
"At this moment, the drama that we have been experiencing for the past several days seems positive and on the winning side. According to the duty meteorologist there have been less than 20 millimetres of rain. So our flood barriers will be able to deal with it. The latest information from the construction site this morning is that the water is being held back by the barriers," he commented.
Yle meteorologist Henri Nyman has predicted another band of rain that will move east over southern Finland on Saturday, dissipating towards evening.
Floods threatening other parts of the south
Jaatinen noted that flooding had occurred in other parts of the metropolitan region.
For example persistent rains had flooded the northern part of Ring Road 3 on Vihdintie. The road is still open, but the speed limit has been reduced, he added. Other problem areas have been identified in Sipoo, Kirkkonummi and Vihti.
"If you look at all of southern Finland, no roads in the state network have been closed because of flooding," he concluded.