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Attachment D The fo/lowing potential counter measures can reduce GRADE SEPARATION ..roblerns encountered by, pedestrians at busy intersections: " Grade separation allows one mode to pass over another, a · Improving law enforcement pedestrian under the automobile with an underpass or over · Improving driver and pedestrian education an automobile with a bridge~ Though grade separations in- · Clarifying pedestrian and driver actions with .traffic crease pedestrian.safety, convincing people to use them is control devices difficult. There is usually time loss and extra physical effort, · Improving pedestrian signal messages, colors, and so people seeking the shortest route may chance a more dangerous ongrade crossing. Barriers can be installed to displays reduce ongrade crossing, but their.installation would sug- · Improving signal timing · Improving crosswalk applications gest an error in judgment in the design of the road and over/ · Shielding vehicle and pedestrian signals underpass' · Improving visibility through lighting, etc. · Providing far-side bus stops Overpass. Extensive pedestrian bridge development may · Increasing driver and pedestrian sight distances, cause pedestrians to abandon the street below, and lower · (Urban Intersection Improvements for Pedestrian Safety that street's qualiW. The street may become more hazar, DOT-FH-11-8533, December 1977) dous and unpleasant to those forced to walk there and the increased auto orientation may pervade the street beyond ! ~ where the bridges end. Pedestrians are effective agents in requiring that streets be pleasant, and should not be removed . '..' from this advocacy position. / To be sure, there are isolated urban developments with extensive second level pedestrian plazas, GOlden Gateway in San Francisco, the Barbican in London and Nicollette Mall in Minneapolis, as examples. New large-scale develop- .. ' i merits can often include grade-separated pedestrian cross- ..~ '-' ~ . ings at cost lower than on~jrade crossing when calculated over the project's life. There are two reasons for lower long-term costs. First, new construction is less expensive than remodeling. Second, long-term cost/benefits to drivers 0~ and pedestrians may outweigh the initial construction cost if the time saved by drivers not having to wait for crossing pedestrians, or the cost of installing signals at a later date, Open views of pedestrians at busy street crossings, or intangible benefits to pedestrians of not being harassed at a busy intersection are included. CONTROLLED CROSSINGS A signalized crossing becomes advantageous to vehicular traffic when pedestrian flows reach about 700 per hour. At this pedestrian density, a signal will delay both pedes- trian and vehicles, but vehicles will be delayed a shorter time than with intermittent pedestrian crossings. Inter- sections requiring signals are usually problem crossings with heavy, fast moving traffic or unusual configurations, and ENERGY EXPENDITURES are difficult to make completely safe. It takes approximately six times the amount of human Most pedestrian crossings are designed to favor the auto- energy to use an underpass as to walk directly across the mobile, forcing walkers to wait for a chance to cross. This street on-grade. It takes approximately nine times the is true even of self-activated .pedestrian crossing .signals. amount of human energy to walk up and over an overpass · Once the button is pushed, a time<lelay mechanism is set as it does to cross the same street on-grade. Crossing over- into motion which eventually stops auto traffic. Pedestrians head requires more energy as the overpass has more head- room requirements than an underpass, therefore, there are usually prefer no more than a 20~econd delay. Any longer more steps to climb up and down. delay increases frustration and may prompt some pedes- trians to cross against the red light. 3? City Council Agenda page 289