Design Speed (mph) 15-30 35-40 45-50 50+
Spacing (ft) Between: offset-intersections intersections (IS, ft) (OS,ft) 200 250 350 500
50 75 150 500
Intersection Space Guidelines In most situations, only a minimum spacing is recommended. However, for streets in urban areas, maximum spacings are also recommended to enable a proper density of connecting street network. Frequently, intersection spacing is not a controllable element of intersection design, and the spacing is “given� as a fixed condition. In such circumstances, spacing guidelines are not applicable. However, in many situations, particularly involving areas of new development, intersection spacing is an important part of the context, and should be considered in light of the above guidelines. Most intersections have three or four legs, but multi-leg intersections (five and even six-leg intersections) are not unusual. Examples of intersection configurations frequently encountered by the designer are shown in Exhibit 6-5. Ideally, streets in three-leg and four-leg intersections cross at right angles or nearly so. However, skewed approaches are a regular feature of intersection design. When skew angles are less than 60 degrees, the designer should evaluate intersection modifications to reduce the skew. street length guideline
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