A
street gutter is a depression running parallel to a
road designed to collect rainwater flowing along the street and divert it into a
storm drain. A gutter alleviates water buildup on a street, allowing pedestrians to pass without walking through puddles and reducing the risk of
hydroplaning by road vehicles. When a
curbstone is present, a gutter may be formed by the convergence of the road surface and the vertical face of the
sidewalk; otherwise, a dedicated gutter surface made of concrete may be present.