St. Louis-area residents may see a new fee on their sewer bills at the beginning of 2020. That's because the Metropolitan St. Louis Sewer District wants to impose a new fee to help fund efforts to resolve flooding and erosion issues in its service area.

In a proposal MSD submitted to its independent rate commission on Monday, the district estimates the cost of resolving the region's stormwater runoff issues to be $560 million. The plan would charge an average of $2.25 per household per month, or $27 per year. The more surface area a property has that can't absorb water, the higher the fee. According to MSD projections, the new fee would generate $30 million per year for 30 years.

The district currently does not have enough funding to respond to residents' reports of stormwater issues, MSD executive director Brian Hoelscher said.

"Sometimes we can do something about it. Sometimes there isn't enough funding," Hoelscher said. "But we can assist with some engineering advice that you might be able to do yourself."

The fee would pay for a number of different solutions to address flooding — which could include upgrading storm systems, planting vegetation to slow and filter stormwater, or buying properties that are severely threatened.

MSD previously attempted in 2008 to enact a fee to manage stormwater, but the Missouri Supreme Court found it unconstitutional. In 2016, voters approved Proposition S, which charges customers a tax that provides MSD with revenue to correct stormwater sewer issues in the area — but that fee does not address flooding and erosion.

St. Louis city and county residents could vote on the latest measure as early as April 2019.

An earlier version of this story misstated the amount of money MSD's proposed see would raise.

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