Colchester officials have figured out a way to pay for the town’s increasing obligation to protect water quality in Malletts Bay.

Public works director Bryan Osborne and a committee of community leaders presented an ordinance change proposal to the selectboard last week that would impose a fee on all property owners based on the amount of impervious surface on their parcels.

The town currently tackles stormwater management projects with a property-tax-funded budget of about $450,000, according to Osborne. If the fee scheme is implemented by next fiscal year, it will nearly double the town’s stormwater management budget. That will still only be about a third of the annual need, Osborne said.

Stormwater infrastructure removes pollutants from storm runoff before it enters Lake Champlain.

“As a lakeside community, while we are doing a lot, we’re really only scratching the surface,” he said. “We are simply not doing enough. We have so many areas where the drainage systems are old and failing. We have so many parts of town that don’t have any drainage systems at all.”

Three other nearby communities have implemented a fee-based stormwater management budget: Burlington, South Burlington and Williston. The selectboard plans public hearings on the issue this fall.

The change would create a stormwater fund and billing/collection system separate from property tax collections. All homeowners would pay the same fee based on an average of residential impervious surfaces in town. Impervious is defined in the ordinance as any thing that does not allow the normal infiltration of rain water into the ground — such as driveways, patios, roofs and awnings.

“There will be a uniform price that all single-family residential properties pay,” Osborne said.

He expects the homeowner fee will roughly equal the reduction in property taxes that comes with taking stormwater management out of the town’s general fund.

Contributions would increase for most commercial properties.

The ordinance would also allow the town to collect stormwater fees for the first time from government and non-profit properties exempt from property taxes. These include St. Michael’s College, University of Vermont buildings, local churches and the federal lands of the Vermont National Guard at Camp Johnson.

New revenue would also come from the Vermont Agency of Transportation for the impervious surfaces associated with the Colchester sections of Route 7 and Interstate 89.

Even the municipality would pay into the fund based on its own buildings and roads. The only properties exempted in the proposal are undeveloped parcels with less than 500 square feet of impervious surfaces.

Before public hearings this fall, Osborne will quantify all the impervious surface subject to the fees to hone estimates of homeowner costs and how much revenue the program will generate.

Property owners will be allowed credits to reduce their fees if they have stormwater infrastructure in place. St. Mike’s, for example, has its own stormwater treatment system to handle the campus’ impervious surfaces.

The move to a fee-based system was recommended by a 2012 Environmental Protection Agency study of Colchester’s water resources. It would coincide with the state’s increased clean water requirements under the 2015 Clean Water Act and stricter runoff regulations in the federal Lake Champlain cleanup plan the EPA revised earlier this year.