Kokemäenjoki river reaches historic low water levels

The water level of the Kokemäenjoki river in Pori, southwestern Finland, has dropped to a historic low for this time of year, with flow rates at their lowest in nearly a century of record-keeping, reports Yle.

Measurements of the river’s water level and flow have been recorded since 1931, but current spring readings are unprecedented, according to Juha-Pekka Triipponen, head of the southern waterway unit at the Southwest Finland Centre for Economic Development, Transport and the Environment.

“This is truly an exceptional situation,” Triipponen said. “Normally, the river flows at around 300 cubic metres per second this time of year. Now, it has been flowing at just 50 cubic metres per second for some time.”

The river’s surface is roughly one metre lower than usual, a result of months of exceptionally dry weather and minimal snowfall. Over the past five months, total precipitation in the Satakunta region has been under 100 millimetres—far below the annual average of 600 millimetres.

“There was hardly any snow, and the spring flood was barely noticeable—it passed almost instantly,” Triipponen explained. “There simply isn’t enough water.”

While rain is forecast in the coming days, Triipponen noted it would likely be absorbed by the parched ground rather than raising water levels. Low groundwater reserves could also pose challenges for smaller water cooperatives in the long term, though larger suppliers have prepared for shortages.

Despite the low water, the river’s main navigation channels remain deep enough for boating, according to Timo Wallin, a professional riverboat captain with 25 years of experience on the Kokemäenjoki. However, side channels and shallower areas near the river mouth are more affected.

Sea levels in the region, which influence the river’s height near Pori, were also historically low this winter—80 centimetres below normal—though they have since stabilised. Wind patterns and shifts in the Baltic Sea’s water distribution contribute to these fluctuations.