Christo signs a poster depicting the potential "Over the River" project in this undated photograph.
Environmental concerns aside, opponents also say the project could negatively impact the local economy by causing increased traffic and lane closures along the stretch of Highway 50 that runs through the region.
Christo's team said that construction will take place only during non-summer months, when traffic is relatively light.
But ROAR's Neville, a local fly-fishing guide, said that strategy won't be enough to save many businesses.
"Fall and spring make up two thirds of our year in terms of when we make our income," Neville said.
"If we have to stop for those traffic delays—even if it's only five minutes in each direction—we won't be able to fit all the [tourist] shuttles in a day. We barely make it as it is. You add that in there, and we can't do it."
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