Long Beach could receive at least $5 million a year in funding for clean water efforts if Los Angeles County’s Measure W parcel tax passes, city officials said.

Under the measure on the Nov. 6 ballot, homeowners and property owners would pay a 2.5-cent tax per square foot of “impermeable area,” meaning buildings, driveways, concrete patios and swimming pools would all be subject to tax.

Measure W is estimated to raise about $300 million a year in funding for projects to capture and treat rainwater for cleaner beaches and increased water reserves.

The average cost to a homeowner would be about $83 a year, advocates said. (Calculate your tax here.)

Proponents say the measure will reduce pollution while strengthening the county’s capacity to capture billions of gallons of runoff that otherwise would end up in the ocean.

But not everyone is in favor.

Opponents say Measure W would be a burden to homeowners and businesses in an already highly-taxed county.

David Kline, a spokesman for the California Taxpayers Association, said a major concern is that the measure has no sunset, meaning the tax is a permanent source of funding.

“When any government agency has a dedicated source of revenue forever, whether they do a good job or not, it’s a recipe for inefficiency,” he said. “This will never come back to voters, so they don’t have to prove they’re spending the money wisely.”

Kline said there’s also confusion over the definition of impermeable surface, which would likely result in battles between homeowners and the county over what counts as impermeable, he said.

“It would create a lot of bureaucracy that’s completely unnecessary and has no expiration date,” he said.

While some homeowners may wince at yet another tax, the measure would bring a significant source of funding for cash-strapped clean water programs in Long Beach, said Alvin Papa, an assistant engineer with the city’s Public Works Department.

If Measure W passes, Long Beach is slated to receive at least $5 million a year for city projects, with the chance of more funding for regional projects, he said.

“This is huge because for the first time we would have a dedicated and reliable funding source,” he said. “I think this would have a tremendous impact.”

Papa said the $5 million would fund new projects while expanding existing ones. The money, for example, could help establish a team in the city’s inspection department, which visits 2,000 businesses twice a year to ensure storm water compliance regulations.

The measure could also fund the city’s effort to put trash-capturing devices on all storm drains as part of a state requirement, he said. The project costs about $300,000 a year, which currently comes from the general fund, he added.

Long Beach’s $30 million Municipal Urban Stormwater Treatment (MUST) project, set to be built next year near Shoemaker Bridge on the Los Angeles River, could get a boost in funding, he said. The project, the first of its kind in size, will capture and treat runoff and stormwater that normally flows into the river.

In addition to the municipal programs, the city could receive millions more in funding for regional projects since it sits in two of the region’s nine watersheds, Papa said.

“We’re a very good candidate for that,” he said. “It’s a huge opportunity that doesn’t come very often.”