The Hennepin County Board on Tuesday approved $2.4 million in special tax levies for four water quality improvement projects in the county’s northern and central suburbs.

Levies for the projects, ranging from flood mitigation to stabilizing streams, were requested by watershed management commissions for Bassett Creek, Elm Creek, Shingle Creek and the Mississippi River.

The Bassett Creek project consists of a long-term flood mitigation plan at Medicine Lake Road and Winnetka Avenue in New Hope, and water quality improvement of Westwood Lake and DeCola Ponds in St. Louis Park.

The projects also aim to reduce phosphorus pollution and collect stormwater runoff from the Westwood Hills Nature Center in St. Louis Park.

The County Board approved a $1.4 million levy for the project, which has a total cost of $4 million. The balance of the project will be paid with a state grant to the city of Golden Valley, said Laura Jester, administrator of the Bassett Creek watershed commission.

The other three recipients approved for levies were:

• Elm Creek watershed commission, $462,500 for stream stabilization projects at Rush Creek in Maple Grove, two sites along Elm Creek in Plymouth and Champlin, and Downs Road Trail rain gardens in Champlin;

• Shingle Creek watershed commission, $479,900 for an infiltration project at Becker Park in Crystal and a soluble reactive phosphorus reduction project in Crystal and Brooklyn Park;

• West Mississippi watershed commission, $53,025 for a best management practices cost-share program for small infiltration and water quality treatment projects.

Some watershed commissions, such as Bassett Creek’s, make annual special levy requests, Jester said. The commission’s yearly requests are pretty consistent, she said.

Watershed commissions don’t have the ability to levy taxes for improvement projects, and so must get them signed off by the County Board. The commissions determine the cost for a special tax district and the board establishes the maximum levy amount for the project, which is included in truth in taxation statements sent to property owners.