Waterloo officials are starting a campaign trying to convince voters to extend the local option sales tax in a vote August 20th. The tax has passed three times in Black Hawk County, but the stakes are a little higher this time. Sixteen million dollars in Vision Iowa money from the state depends on the tax being extended. Ross Christenson is co-chair of the “Yes to Progress” campaign.He says the tax isn’t new, it’s the same tax with a portion of it now earmarked for the River Renaissance project. Christenson says failing to pass the extension now will cost citizens later.He says he can’t guarantee there won’t be any tax increases with the referendum. He says there will be tax increases without the extension.He says the river project will bring more people into the county and increase the tax base. Christenson says they’ll hold a series of public hearings on the issue between now and the election.