In recent weeks, warmer weather and rain has caused localized flooding in the City of Fridley and staff is preparing for more to come.
According to Public Works Director James Kosluchar, the public works and public safety departments documented 66 flooded roadways, parking areas, yards and residential basements this spring. Lucia Lane was closed due to flooding for two days.
Kosluchar said one factor was an unusually warm fall.
“We had a wet autumn in 2018 and it left soil moisture above normal before freeze up,” said Kosluchar.
He added that throughout the entire region, frost depth was up to four feet and there are still packs of snow to be melted.
City staff is expecting 1.5 to 4 inches of water over Fridley’s watershed areas. Where the snow is gone, water has collected in low spots, ditches drainages and marshes.
“In short, there is water waiting to move out of these areas,” said Kosluchar.
Fortunately, the recent mild temperatures have slowed the melt.
“We get a melting period during the day and freezing period at night and that is perfect,” said Kosluchar. “That is what we want to see to reduce the chance for flooding.”
Together with the Coon Creek Watershed District and the city’s watershed district partners, the city has forecasted local areas they expect flash flooding to occur.
Predicted locations that will require clearing include the Springbrook Watershed. Portions of the trail bridge at Riverview Heights Park are currently underwater.
Kosluchar said that city staff is also monitoring the city for any “trouble spots”.
Typically, the National Weather Service forecasts are issued every two weeks in the spring. The most recent probability forecast was issued on March 11, which forecasts river levels through June 9.
“They won’t issue another probability forecast because of the long range, but they are seeing active flood warnings and rising of rivers,” said Kosluchar. “There is a flood warning for the Mississippi River above St. Paul, including Fridley, but there are more severe flood warnings downstream of the confluence with the Minnesota and St. Croix Rivers.”
Kosluchar added that the probability of exceeding flood levels is 20 percent greater than normal.
“In a typical year it is 10 percent,” he said.
The March 11 forecast predicted a 70 percent chance that the river gauge, located on 37th Avenue, will reach the action level of 14 feet and a 20 percent chance it will exceed 17.1 feet, which equals the fifth highest flood on record.
“Many variables can change the forecast very quickly with higher or lower river cresting,” said Kosluchar. “Especially with rainfall at this time. This is a critical period.”
While the most probable timing for flooding is mid-April, the same variables that affect the heights of the river crest can significantly change the forecast and result in earlier or later timing of the river crest.
In 1997, the city installed a flood control gate installed at the Springbrook Creek outfall in Riverview Heights. Equipment to operate this system is mobilized when action levels are reached.
“That equipment is being readied now,” said Kosluchar. “We are getting that ready and making sure that we got some additional pumping capacity out there.”
The city also operates weirs on stormwater systems at Springbrook Nature Center and Locke Lake Dam.
Other preparations by the city include providing sandbags and sand at the Public Works Facility for residents.
“Any amount under 100 bags they can come obtain themselves,” said Kosluchar. “If they have more than 100 bags it becomes cumbersome for them to move so we will bring out sandbags or sand at our cost to the resident.”
At this time, it appears that the city will not require volunteers and temporary barriers for city installation of augmented protection.
“If the levels don’t reach 20 then we are in pretty good shape,” said Kosluchar.
The City of Fridley or Anoka County will issue a request for volunteers if the need is anticipated.
For more information, contact Fridley Public Works at 763-527-3566.