photo credit: Sonoma Water
Water flows over the Mirabel Inflatable Dam on the Russian River.

The Sonoma County Water Agency, known as Sonoma Water, has begun inflating its annual rubber dam on the Russian River. 

The agency typically inflates the dame around the start of the dry season, when the river's natural flow begins to drop and demand increases.

Sonoma Water spokesperson Stuart Tiffen said the main purpose for the dam is to help recharge local groundwater supplies.

"When the dam is fully inflated, it creates a small pool from which Sonoma Water draws for use in four off-stream infiltration ponds," Tiffen said. 

The water in these ponds gets naturally filtered through sand and gravel... eventually it's delivered to homes and businesses.

According to Sonoma Water, there's no dire need this year, and our groundwater supplies are actually in good shape.

"We've had an above average year for rainfall, this is just a best practice," Tiffen said. 

The rubber dam is located upstream from Forestville and downstream from Wohler Bridge. He said inflation has been under way since May 29.

"Inflating the dam will usually take anywhere from four and fourteen days," said Tiffen.

When fully inflated, it will mean a few changes for those recreating on the river

"Boaters will need to portage around the dam itself and there are signs posted upstream and downstream of the dam letting folks know not to recreate on or near it," Tiffen said.

Fish, however, get a helping hand around the dam, for the sake of science

"There's a permanent fish ladder at the site of the dam," Tiffen said. "That's actually one of the ways that our biologists keep track of fish migrations later on in the year as their coming upstream."