Get set for a 148 percent increase in water bills over 10 years — unless the city builds a new filtration plant.

Then bills would soar 171 percent.

That was the sobering conclusion of the Independent Budget Office, which issued a report yesterday analyzing what would happen if the EPA requires filtration of water from the Catskill/Delaware watershed.

The city is spending $630 million to protect the watershed and avoid a costly filtration plant.

The IBO said that given the trend in rate increases, by 2016, water bills for a one-family home could hit $1,500.