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In 1972, after Pasadena residents complained about highway noise and visual pollution, parts of the 210 were built below grade—city streets were scooped out to create a sunken section of freeway. The once underground telephone and water lines were kept at their original level, however, and encased in a 94-inch-wide span of concrete that stretched over the freeway. The solution may not be pretty, but it was cheaper than digging up and relocating all those lines.