Table 1.2: Required Intersection Radii for ROW Preservation Inter- section Type Approach Classes Conservative Assumption Radi- us (ft) PA_PA Principal Arterial × Principal Arterial Interchange-ready major node; future grade separation or dual lefts in all directions 175 ft
Enhanced arterial intersection; dual lefts on PA, long storage High-capacity intersection; extended left-turn storage on PA Arterial-collector node; full turn lanes on PA Major signalized node; dual or long-storage lefts Enhanced arterial intersection; left-turn pockets on MA Arterial-collector intersection Minor arterial intersection; single lefts
PA_MA Principal Arterial × Major Arterial PA_MiA Principal Arterial × Minor Arterial PA_MC Principal Arterial × Major Collector MA_MA Major Arterial × Major Arterial MA_MiA Major Arterial × Minor Arterial MA_MC Major Arterial × Major Collector MiA_MiA Minor Arterial × Minor Arterial MiA_MC Minor Arterial × Major Collector MC_MC Major Collector × Major Collector
150 ft
130 ft
120 ft
150 ft
120 ft
110 ft
100 ft
Minor arterial–collector intersection
90 ft
Collector intersection; smallest footprint
80 ft
Figure 1.40: Corner Clip Calculation at Roadway Intersections
To determine corner clip dimensions: measure the radius along each approach centerline from the intersection center point. Subtract one-half the ultimate ROW width of that approach to find the corner clip leg length, measured along the ROW line from the intersection corner point, as shown in Figure 1.39. Where intersecting roadways have the same ROW width, both legs are equal. Ultimate ROW widths are established by the adopted cross-sections in Section 1.7.2. Requests for deviation are subject to the amendment or waiver process in Section 1.9. Note: On established corridors where existing ROW is less than the ultimate width, corner clip dimensions shall be calculated using existing ROW. On developing corridors, ultimate ROW as established in the adopted cross-section shall govern. Requests for deviation are subject to the amendment or waiver process in Section 1.9.
Corner clip formula Leg A = radius − ½ ROW of Road B Leg B = radius − ½ ROW of Road A Legs are equal where both roads have the same ROW width.
Example: MiA x MiA (both 4-lane) Radius = 100 ft (from Table 1.1)
ROW(MiA, 4-lane) = 118’ ½ ROW(MiA, 4-lane) = 59’ Leg A = 100 − 59 = 41 ft Leg B = 100 − 59 = 41 ft
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Master Roadway Network | Fort Worth Master Transportation Plan
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