While walking downtown for lunch, my co-workers and I noticed white rectangles painted on the sidewalk at Grape and Main streets, but we couldn't figure out what they were for. Each corner had two white blocks, set off by cones. What are these markings?

While walking downtown for lunch, my co-workers and I noticed white rectangles painted on the sidewalk at Grape and Main streets, but we couldn't figure out what they were for. Each corner had two white blocks, set off by cones. What are these markings?

— M.T., Medford

It looks like you caught the city's paint crew at lunch while they waited for the paint to dry. Public Works Director Cory Crebbin said the bright white shapes painted on the sidewalk are the backdrops for new notices banning bikes and skateboards from downtown sidewalks.

Crews had been out earlier this summer with white paint to stencil corners with the reminder about the law. However, the wildfire smoke that has filled the air so much of this summer also lays down a fine layer of particulates that mingles with the rest of the dust stirred up by traffic and sticks in wet paint. By the time the signs dried, they were dingy and not nearly as brightly legible as crews wanted, Crebbin said.

A redesign was clearly in order, and those bright, white boxes you saw are part of the solution. Crews are painting the white rectangles first, then going back to stencil the legal reminder in red, he said.

Crews painting crosswalks and center lines also have been plagued with dingy whites this summer, Crebbin said. Painting can't be put off until later, though, because the winter rains that finally will douse the forest fires aren't good for painting either.

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