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OCR for page 107
107 APPENDIX L Two-Way Left-Turn Lanes ALABAMA FLORIDA The typical spacing between arrows is 32 ft. The spacing between arrows is 12 ft. The minimum interval between sets of arrows is 200 ft, The maximum interval between sets of arrows is 300 ft. but an interval of 400 ft is desirable (measured as the space between the bottoms of the nearest arrows in each set). GEORGIA ARIZONA The spacing between arrows is 25 ft. The typical spacing between arrows is 32 ft. IDAHO The use of pavement arrows is optional. The spacing between the tips of the arrowheads is 18 to 32 ft, depending on the prevailing speed. ARKANSAS The maximum interval between sets of arrows is 300 ft The spacing between arrows is 32 ft. (measured from the center point between a pair of arrows to the center point between the next pair of arrows) if the ADT A set of arrows is placed 100 ft (measured to the center of the roadway is more than 10,000. If the ADT of the road- point between the pair of arrows) from the beginning or end way is less than 10,000, the maximum interval between sets of the two-way left-turn lane even when it is interrupted for of arrows is 500 ft. Sets of arrows should be placed such that the tip of the nearest arrowhead is no closer than 50 ft to the a one-direction left-turn lane at an intersection. A set of arrows nearest edge of an intersecting street. is placed 100 ft (measured to the center point between the pair of arrows) from side streets if a gap is placed in the lane line markings for the two-way left-turn lane. The interval be- ILLINOIS tween sets of arrows is 500 to 1,000 ft in urban areas and 1,300 to 1,500 ft in rural areas. At least two sets of arrows shall be used. Additional sets of arrows shall be placed at 200- to 300-ft intervals. CALIFORNIA INDIANA The distance between the tips of the arrowheads is generally equal to the left-turn arrow size. Although the typical left- The typical spacing between the tips of the arrowheads is turn arrow is 8 ft long, an arrow that is 24 ft long may be used 32 ft. on high-speed roadways. The minimum interval between sets of arrows is 400 ft The use of pavement arrows is optional. (measured from the center point between a pair of arrows to the center point between the next pair of arrows). COLORADO IOWA The typical spacing between the tips of the arrowheads is 32 ft. The typical spacing between the tips of the arrowheads is 32 ft. DELAWARE The typical interval in feet between sets of arrows is ten times the speed limit in mph (measured from the center point The typical spacing between the tips of the arrowheads is between a pair of arrows to the center point between the next 32 ft. pair of arrows), or one set of arrows located midblock.

OCR for page 107
108 KANSAS Each segment of a continuous two-way left-turn lane is considered separately. If the segment is shorter than 350 ft, The typical spacing between arrows is 16 ft. one set of arrows is placed in the center of the segment. If the segment is longer than 350 ft, the first set of arrows is placed The typical interval in feet between sets of arrows is ten 50 to 100 ft from the beginning or end of the segment and times the speed limit in mph (measured from the center point additional sets of arrows are placed at 250-ft intervals (mea- between a pair of arrows to the center point between the next sured from the center point between a pair of arrows to the pair of arrows). center point between the next pair of arrows). LOUISIANA MONTANA The typical spacing between the tips of the arrowheads is The spacing between the tips of the arrowheads is no less 32 ft. than 10 ft and no more than 20 ft. At least one set of arrows is placed per block. The maxi- A set of arrows should be placed 50 ft from intersections mum interval between sets of arrows is 750 ft. or the ends of single-direction turn lanes. At least two sets of arrows should be used per block. The typical spacing be- tween sets of arrows is 500 ft in urban areas and 1,320 ft in MARYLAND rural areas. The typical spacing between arrows is 16 ft. NEBRASKA The typical interval between sets of arrows is 800 ft (mea- sured as the space between the bottoms of the nearest arrows The spacing between the tips of the arrowheads is 24 to 32 ft in each set). in urban areas and 32 to 40 ft in rural areas. A set of arrows shall be placed on each approach to all NEVADA intersecting streets at a distance of 50 ft from the beginning of the centerline markings. The spacing between the tips of the arrowheads is 8 to 16 ft. MICHIGAN NEW HAMPSHIRE The spacing between the tips of the arrowheads is 32 ft. The spacing between the tips of the arrowheads is 8 ft. The interval between sets of arrows can range from 300 to A set of arrows should be placed no less than 50 ft and no 1,000 ft (measured as the space between the bottoms of the more than 100 ft from the end of a single-direction turn lane nearest arrows in each set) as determined by the region traf- (this distance is measured from the tip of the nearest arrow- fic engineer. head to the end of the two-way left-turn lane). MINNESOTA NEW YORK The spacing between the tips of the arrowheads is 8 to 16 ft. The spacing between arrows is 5 ft. The maximum interval between sets of arrows is 200 ft The typical interval between sets of arrows is 200 ft (mea- (measured from the center point between a pair of arrows to sured as the space between the bottoms of the nearest arrows the center point between the next pair of arrows). in each set). Sets of arrows should be placed such that the center point A set of arrows should be placed 21 ft (shown as 6.5 m) between a set of arrows is 50 ft from the resumption of the from the end of a single-direction turn lane (this distance is centerline markings when they are interrupted for an inter- measured from the bottom of the nearest arrow to the end of secting street. the two-way left-turn lane). MISSISSIPPI NORTH CAROLINA The spacing between arrows is 10 ft. The spacing between arrows is 10 ft.

OCR for page 107
109 The typical interval between sets of arrows is 320 ft (mea- TENNESSEE sured from the center point between a pair of arrows to the center point between the next pair of arrows). The spacing between arrows is typically 32 ft. The maximum interval between sets of arrows is 0.5 mile. OHIO Arrows shall not be placed within 100 ft of intersecting The spacing between the tips of the arrowheads is 8 to 16 ft. roadways. The interval between sets of arrows should be 500 ft to TEXAS 1,000 ft for speeds up to 40 mph, and 1,000 ft to 1,500 ft for speeds of more than 40 mph. The use of turn arrows is optional. If used, the spacing be- tween the tips of the arrowheads is typically 8 to 16 ft. A set of arrows should be placed 100 to 200 ft from the near edge of intersecting roadways or from the ends of the If turn arrows are used, the maximum interval (measured two-way left-turn lane. from the center point between a pair of arrows to the center point between the next pair of arrows) between sets of arrows is 1,500 ft and the minimum interval between sets of arrows OKLAHOMA is 150 ft. The spacing between arrows is 16 ft. UTAH The interval between sets of arrows is 200 ft (measured as the space between the bottoms of the nearest arrows in The use of turn arrows is optional. If used, the spacing each set). between the tips of the arrowheads is typically 33 ft. If turn arrows are used, the maximum interval (measured A set of arrows is placed 30 ft from the ends of the two- between the tips of the arrowheads of the nearest arrows) way left-turn lane, including when they are interrupted for between sets of arrows is 300 ft and the minimum interval intersecting roadways. between sets of arrows is 100 ft. OREGON WASHINGTON The typical spacing between arrows is 8 to 16 ft (however, The spacing between the tips of the arrowheads is 5 to 10 ft. Figure 20 of Oregon's Traffic Line Manual says that the typ- ical spacing between the tips of the arrowheads is 30 ft). The maximum interval (measured from the center point between a pair of arrows to the center point between the next The minimum interval between sets of arrows is 250 ft pair of arrows) between sets of arrows is 500 ft. A set of (measured from the center point between a pair of arrows to arrows is placed approximately 100 ft from the ends of two- the center point between the next pair of arrows). Sets of way left-turn lanes. arrows should be placed at even intervals, proportioned within each block, with the approximate interval in feet being ten WEST VIRGINIA times the posted speed limit in mph. The spacing between arrows is typically 32 ft. PENNSYLVANIA The typical interval (measured from the center point be- tween a pair of arrows to the center point between the next The spacing between the tips of the arrowheads is 8 to 16 ft. pair of arrows) between sets of arrows is 200 to 500 ft. The typical interval between sets of arrows is 320 ft (mea- sured from the center point between a pair of arrows to the WISCONSIN center point between the next pair of arrows). The spacing between arrows is 32 ft. SOUTH DAKOTA The maximum interval between sets of arrows is 400 ft. Sets of arrows should be placed near intersections or drive- The spacing between the tips of the arrowheads is 16 ft. ways with turning traffic.

OCR for page 107
110 WYOMING point between a pair of arrows to the end of the two-way left- turn lane). The typical spacing between the tips of the arrowheads is 32 ft. No standards were found for: CHARLOTTE, NC Alaska Rhode Island Connecticut South Carolina The spacing between the tips of the arrowheads is 15 ft. Hawaii Vermont Kentucky Virginia The maximum interval (measured from the center point Maine District of Columbia between a pair of arrows to the center point between the next Massachusetts Puerto Rico pair of arrows) between sets of arrows is 300 ft and the min- Missouri Los Angeles, CA imum interval between sets of arrows is 100 ft. New Jersey New York, NY New Mexico Tucson/Pima County, AZ A set of arrows is placed 25 ft from the end of a single- North Dakota direction turn lane (this distance is measured from the center