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5 CHAPTER TWO PAVEMENT MARKINGS AT INTERSECTIONS TURN LANES may be used to convey either guidance or mandatory messages. The ONLY word marking (see Figure 3B-20) may be used to Figure 2 illustrates some of the characteristics of turn lanes supplement lane-use arrow markings (see Figure 3B-22)." and their associated pavement markings. Paragraph 23 of Section 3B.19 contains the following support: "Lane-use arrow markings are often used to provide 2003 MUTCD Provisions guidance in turn bays (see Figure 3B-22), where turns may The MUTCD does not require or recommend a specific type or may not be mandatory, and in two-way left-turn lanes (see or width of lane line turn lanes and adjacent through lanes. Figure 3B-7)." Figures 3B-7, 3B-11, and 3B-22 show a normal solid lane line between the turn lane and the adjacent through lane. Paragraph 6 of Section 3B.19 contains the following guid- Figures 3B-11 and 3B-22 show the upstream end of the solid ance: "Except for the two opposing arrows of a two-way left- lane line to be lined up with the upstream end of the full- turn lane marking (see Figure 3B-7), the longitudinal space width turn lane (see Appendix A for figures). between word or symbol message markings, including arrow markings, should be at least four times the height of the char- Paragraphs 3 and 4 of Section 3B.04 contain the follow- acters for low-speed roads, but not more than ten times the ing standards: "Where crossing the lane line markings with height of the characters under any conditions." Because both care is permitted, the lane line markings shall consist of a the left-turn (or right-turn) arrow symbol and the ONLY normal [4- to 6-in.-wide] broken white line. Where crossing word marking typically have a height of 6 to 8 ft, this guid- the lane line markings is discouraged, the lane line markings ance essentially states that the space between word or sym- shall consist of a normal [4- to 6-in.-wide] solid white line." bol message markings should be no less than 24 to 32 ft and no more than 60 to 80 ft. Paragraphs 5 and 6 of Section 3B.04 contain the following options: "Solid white lane line markings may be used to sep- Type of Lane Line Between a Turn Bay and arate through traffic lanes from auxiliary lanes, such as uphill Adjacent Through Lane (47 agencies) truck lanes, left- or right-turn lanes, and preferential lanes. They may also be used to separate traffic lanes approaching Except for the five agencies cited here, the design standards an intersection. Wide [8- to 12-in.-wide] solid lane line mark- consistently show only a solid lane line between a turn bay ings may be used for greater emphasis." and the adjacent through lane. For turn lanes where a through lane becomes a mandatory The design standards for South Carolina show a broken turn lane, the legends in Figures 3B-11 and 3B-22 note that the lane line (10-ft segments with 30-ft gaps) being used between use of turn arrows is required, and the legend for Figure 3B-22 the turn lane and the adjacent through lane. states that the use of ONLY word markings is optional. For separate left-turn bays, the legends in Figures 3B-7, 3B-11, The design standards for Maryland state that the solid lane and 3B-22 note that the use of turn arrows is optional. line between the turn lanes and the adjacent through lane starts at the stop line and ends at the halfway point of the full- Paragraph 14 of Section 3B.19 contains the following width turn lanes. A dotted line (3-ft segments with 9-ft gaps) standard: "Where through traffic lanes approaching an inter- may be used from the halfway point to the upstream end of section become mandatory turn lanes, lane-use arrow mark- the full-width turn lanes. ings (see Figure 3B-21) shall be used and shall be accompa- nied by standard signs." Although this standard is universally The design standards for New Hampshire show a broken followed, no standard is given regarding the use of ONLY lane line (10-ft segments with 30-ft gaps) being used up- word markings or the number or placement of turn arrows. stream of the upstream end of the solid lane line between the turn lane and the adjacent through lane, even for turn bays. Paragraphs 17 and 18 of Section 3B.19 contain the follow- The length of the broken lane line is based on the posted ing options: "Lane-use arrow markings (see Figure 3B-21) speed limit.

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6 Upstream end of full-width turn lane Dotted line in Turn lane Separate turn bay turn lane taper taper Lane lines Adjacent through lane Dropped lane ONLY word marking Turn arrow FIGURE 2 Characteristics of turn lanes. The design standards for North Carolina show that if the WY (right-turn lanes)--0.5L (an optional dotted line length of the full-width turn lane is more than 250 ft, the solid comprised of 2-ft segments with 6-ft gaps may be used lane line starts at the stop line and ends 250 ft upstream from from the upstream end of the lane line to the upstream the stop line. A 4- or 6-in.-wide dotted line (2-ft segments end of the right-turn taper) with 13-ft gaps) starts at the upstream end of the solid lane DE, NV, PA--0.33L line and ends at the upstream end of the left-turn lane taper. MN, WA--50 ft FL--20 to 120 ft (based on speeds ranging from 35 to The design standards for West Virginia show that a solid 65 mph) lane line with a maximum length of 200 ft is used between MT--20 ft the turn lane and the adjacent through lane. A broken lane line ID--10 ft (10-ft segments with 30-ft gaps) is used between the turn lane MI--0 ft for left-turn lanes and 25 ft for right-turn lanes and the adjacent through lane upstream of the solid lane line for NC--0 ft for turn lanes that are 250 ft or less in length (for the remainder of a full-width turn lane that is longer than 200 ft. turn lanes longer than 250 ft, the solid lane line ends 250 ft upstream from the stop line) AK, AZ, NE, OK, SD, TN, VT, VA, WI, WY (left-turn Width of Lane Line Between a Turn Bay and lanes), PR, LAN, TUC--0 ft. Adjacent Through Lane (31 agencies) The design standards for Utah state that the solid lane line The following widths are explicitly specified in the design starts at the stop line and ends at least 100 ft upstream from standards for the lane line between a turn bay and the adja- the stop line. cent through lane: AR, DE, IN, ME, MI, NE, SD, TN, VT--4 in. Other Considerations Regarding Lane Lines for Turn Bays (1 agency) NC, PA--4 or 6 in. FL, KS--6 in. The design standards for Idaho (see Figure 3) show that the WV--6 to 8 in. centerline on the left-hand side of a turn bay extends beyond AL--6 or 8 in. the stop line and terminates at the nearest crosswalk line. The AK, CA, CO, ID, LA, MT, NV, ND, OH, OR, TX, UT, last 30 ft of the centerline (including the portion beyond the WI, WY, DC--8 in. stop line) is a solid yellow median that is 2 to 4 ft wide (if AZ--12 in. space is limited, the solid yellow median can be as narrow as 8 in. wide). The double yellow centerline separates into a pair Length of Lane Line Between a Turn Bay of double yellow centerlines that taper away from each other and Adjacent Through Lane (26 agencies) to connect to the edges of the solid yellow median. The following points (measured downstream from the up- Type of Lane Line Between a Dropped Lane stream end of the full-width turn lane) are explicitly specified and Adjacent Through Lane (14 agencies) in the design standards for the upstream end of the solid lane line between a turn bay and the adjacent through lane Except for the four agencies listed here, the design standards (L is the length of the full-width turn lane): consistently show a solid lane line between a dropped lane and the adjacent through lane. LA--0.5L MD--0.5L (an optional dotted line comprised of 3-ft seg- The design standards for California note that an 8-in.- ments with 9-ft gaps may be used from the upstream wide solid line preceded by an 8-in.-wide dotted line may be end of the lane line to the upstream end of the full-width placed in advance of an intersection where the outside lane turn lane) is dropped as a mandatory turn lane. The dotted line starts

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7 Mount R3-9 sign overhead and over the two-way turn lane, whenever possible. Use post-mounted R3-10A as an alternate or supplement to R3-9. R3-10A Private Approach R3-9 Maj or or Street Minor Private Street Minor Street Approach 2' - 4' 500' (150m) max. 25' recommended spacing 8'-3" (2.5 m) L/2 L/2 (7.6 m) (600 mm -1.2 m) median 14' and 16' (4.2 and 4.8 m) 30' solid yellow (9.0 m) median width 10' 18' - 32' (5 - 10 m) 50' (15 m) min. (3 m) desirable to the nearest approach or minor street 8" (200 mm) solid white Desirable gap length Variable X = S (speed mph) x 10 2 [X = S (speed km/h)] NOTES: 1. Pavement Markings in the through lanes are optional and should be installed only if justified. 2. Two-way left turn lanes should be continuous through "T" intersections, but may be broken for 4-way intersections. 3. Elimination of double yellow reverse curve may be used at the end of two-way left turn lanes at high volume signalized intersections. 4. See Standard Drwg. I-21 for pavement marking details. FIGURE 3 Solid yellow median used by Idaho DOT (Source: 2003 Idaho DOT traffic manual). where a special RIGHT LANE TURNS RIGHT AHEAD Length of Lane Line Between a Dropped Lane yellow, diamond-shaped warning sign is placed at a distance and Adjacent Through Lane (2 agencies) D upstream from the upstream end of the 8-in. solid line. (The distance D is the advance placement distance in feet for The following lengths are explicitly specified in the design warning signs per the MUTCD.) standards for the solid lane line between a dropped lane and the adjacent through lane: The design standards for Maryland state that the normal broken lane line shall become a dotted line (3-ft segments NC--200 ft with 9-ft gaps) beginning at the farthest upstream turn arrow, KS--561 ft. and shall become a solid lane line at the halfway point between the farthest upstream turn arrow and the stop line. Use Versus Non-Use of Turn Arrows in Turn Bays (47 agencies) The design standards for Oregon show an 8-in.-wide solid line preceded by an 8-in.-wide dotted line (3-ft segments sep- Except for the nine agencies listed here, the design standards arated by 9-ft gaps) being placed in advance of an intersection consistently indicate that the use of turn arrows in turn bays where the outside lane is dropped as a mandatory turn lane. is recommended or required. The design standards for South Carolina show a broken The design standards for Tennessee state that turn arrows lane line (10-ft segments with 30-ft gaps) being used between are typically used in turn bays. a dropped lane and the adjacent through lane. The design standards for five agencies (IA, MD, PA, UT, and WY) state that the use of turn arrows in turn bays is Width of Lane Line Between a Dropped Lane optional. and Adjacent Through Lane (5 agencies) The design standards for Delaware state that the use of The following widths are explicitly specified in the design turn arrows in right-turn bays is optional. standards for the solid lane line between a dropped lane and the adjacent through lane: The design standards for Colorado show turn bays without turn arrows. However, the design standards also show a curved NC--4 to 6 in. extension of the lane line partially into the intersection to com- KS--6 in. municate to drivers when they arrive at the downstream end of AR, CA, FL--8 in. the turn bay that they must turn either left or right.

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8 The design standards for South Carolina note that turn the stop line to the tip of the arrowhead for the turn arrow arrows are typically not used in turn bays. nearest to the stop line: OR--10 ft Use Versus Non-Use of ONLY Word Markings FL, IA--25 ft. in Turn Bays (30 agencies) The following distances are explicitly specified in the The design standards for 11 agencies (AK, AZ, AR, MT, design standards for the distance from the upstream edge of the NV, NY, ND, VT, WI, DC, and PR) state or show that the stop line to the center of the turn arrow nearest to the stop line: use of ONLY word markings in turn bays is required. UT--20 ft The design standards for Tucson/Pima County, Arizona, MD--50 ft. show that the use of ONLY word markings in turn bays is required for long turn lanes. The following distances are explicitly specified in the design standards for the distance from the upstream edge of The design standards for 12 agencies (AL, ID, IA, ME, the stop line to the bottom of the turn arrow nearest to the MA, OH, OK, OR, PA, UT, WV, and WY) indicate that the use stop line: of ONLY word markings in turn bays is optional. NH--40 ft The design standards for six agencies (GA, MD, RI, SC, LA, VA, WV--50 ft. CLT, and LAN) note that ONLY word markings are not used in turn bays. Placement of Word or Symbol Marking Nearest to Upstream End of Full-Width Turn Lane Placement of Turn Arrow Nearest to Stop Line in Turn Bays (22 agencies) in Turn Bays (38 agencies) The following points (measured downstream from the up- The following distances are explicitly specified in the design stream end of the solid lane line between the turn bay and the standards for the distance from the upstream edge of the stop adjacent through lane) are explicitly specified in the design line to the top of the turn arrow nearest to the stop line: standards for the bottom (unless otherwise stated) of the word or symbol marking nearest to the upstream end of the AK, VT--4 ft full-width turn lane: NV--8 ft OH--at least 10 ft from the downstream edge of the stop CA--near the point of entrance line in urban areas and at least 30 ft from the down- WA--0 ft (measured to center of arrow) stream edge of the stop line in rural areas AL, AK, AZ, DE, ID, KS, SD, VT, VA, PR, LAN, SD--17 ft TUC--0 ft ME--20 ft (shown as 6 m) from the downstream edge of MI, NC--0 ft for long turn lanes the stop line WI--0 or 20 ft depending on the turn lane length MA--20 ft (shown as 6 m) OR--10 ft (measured to tip of arrowhead) AZ, IN, WI, WY, TUC--20 ft FL--15 ft MT, PA--at least 20 ft MN--20 ft for long turn lanes OK--20 ft for turn lanes shorter than 150 ft and 30 ft for TN--25 ft longer turn lanes NY--33 ft (shown as 10 m) for long turn lanes. NY--21 ft (shown as 6.5 m) GA, ID, CLT--25 ft Placement of Other Turn Arrows and ONLY Word MI, KS--at least 25 ft Markings in Turn Bays (32 agencies) AL--30 ft MN--30 to 80 ft for turn lanes longer than 200 ft, and at The term "space between" in this section refers to the un- the midpoint of the full-width turn lane for turn lanes marked space between the bottom of a word or symbol mark- of 200 ft or less in length ing and the top of the next upstream word or symbol mark- TX--typically 32 ft ing. The term "interval between" in this section refers to the KY--32 to 80 ft distance between the top (or center or bottom) of a word or TN, WA--50 ft symbol marking and the top (or center or bottom) of the next NC--50 ft for long turn lanes word or symbol marking. MO--75 ft. The following distances are explicitly specified in the The following distances are explicitly specified in the design standards for the space between ONLY word markings design standards for the distance from the upstream edge of and the next downstream turn arrow:

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9 VT--4 ft UT--30 ft AK--4 ft for the turn arrow nearest to the stop line and 35 IA--75 ft between turn arrows (if ONLY word markings to 80 ft for turn arrows farther upstream based on the are used they are centered in the 75-ft distance between speed the subsequent arrows) NY--5 ft GA--100 ft (because all turn lanes are required to have at OR--30 ft least two turn arrows, a shorter spacing may be used AL, TX, WI, WY--32 ft for the second arrow in a short turn lane) MA--32 ft (shown as 9.8 m) WA--100 ft MI--32 ft for 25 mph or less, 48 ft for 30 or 35 mph, 64 LA--125 ft between turn arrows. ft for 40 or 45 mph, and 80 ft for 50 mph or more PR--33 ft The following maximum spaces between subsequent ND--typically 44 ft, but no less than 32 ft word or symbol markings are explicitly specified in the IN, PA--four times the character height for low-speed design standards: roadways and ten times the character height for high- speed roadways. OH--60 ft in urban areas and 80 ft in rural areas AZ, KY, NV--80 ft The following distances are explicitly specified in the AL--200 ft. design standards for the interval between ONLY word mark- ings and the next downstream turn arrow: Other Considerations Regarding Arrows and FL--15 ft Word Markings in Turn Bays (25 agencies) LA--25 ft UT--30 ft The design standards for Arizona state that an ONLY word OK--35 ft for turn lanes shorter than 150 ft and 35 and marking is to be installed midway between the turn arrow 55 ft for longer turn lanes nearest the stop line and the turn arrow nearest to the up- ID, WV--midway between the upstream and downstream stream end of the lane line. The turn arrow nearest to the turn arrows. upstream end of the lane line is always required, but the turn arrow nearest to the stop line may be omitted when the length The following minimum spaces between subsequent word of the turn lane is 150 ft or less. or symbol markings are explicitly specified in the design standards: The design standards for Arkansas show that a 12-in.-wide stop line is used at the end of major street left-turn lanes even OH--24 ft in urban areas and 32 ft in rural areas if no signals or STOP signs are controlling the approach. AZ, KY, NV--32 ft AL--100 ft. The design standards for California note that an 8-ft-long turn arrow is typically used, but that high approach speeds The following typical spaces between subsequent word or may justify the use of a 24-ft-long turn arrow. symbol markings are explicitly specified in the design stan- dards: The design standards for Florida state that for turn lanes where the length of the solid lane line is less than 100 ft, only IL--20 ft in urban areas and 50 ft in rural areas one turn arrow is used. Two turn arrows are used for turn WY, DC--32 ft lanes where the length of the solid lane line is 100 to 150 ft. ME--53 ft (shown as 16 m) between turn arrows if ONLY Three turn arrows are used for turn lanes where the length of word markings are not used; 33 ft (shown as 10 m) the solid lane line is 150 to 200 ft. For turn lanes where the between turn arrows and ONLY word markings if length of the solid lane line is more than 200 ft, an additional ONLY word markings are used turn arrow is added for each additional 100 ft. If more than CLT--50 ft between Turn Arrows 1 and 2 and 3 (where two turn arrows are used, they are spaced evenly between the Turn Arrow 1 is the turn arrow nearest to the stop line), first and last turn arrows. ONLY word markings are used in and 100 ft between Turn Arrows 3 and 4 and 5 and 6, conjunction with lane use arrows where a movement that and 150 ft for any additional upstream turn arrows would otherwise be legal is to be prohibited. WV--72 ft for speeds of 40 mph or less and 168 ft for speeds higher than 40 mph The design standards for Maryland require that for dual KS--no less than four times the character height or more turn lanes, turn arrows shall be placed in each lane at the than ten times the character height. halfway point of the full-width turn lanes. A second set of turn arrows may be placed in each lane halfway between the The following typical intervals between subsequent word required arrows and the upstream end of the full-width turn or symbol markings are explicitly specified in the design lanes (three-quarters of the distance from the stop line to the standards: upstream end of the full-width turn lanes).

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10 The design standards for Michigan provide a second 150- and 200-ft lane lines, a turn arrow is placed such that the option for marking turn lanes that consists entirely of word bottom of the arrow is 40 ft from the stop line, a second turn markings. The top of the letters of an ONLY word marking arrow is placed such that the bottom of the arrow is lined up is placed at least 25 ft from the stop line. The top of the let- with the upstream end of the lane line, and an ONLY word ters of a TURN message is placed upstream a distance D marking is placed halfway between the two turn arrows. For from the bottom of the letters of the ONLY word marking, 250-, 300-, and 350-ft lane lines, a turn arrow is placed such and the top of the letters of a LEFT message is placed that the bottom of the arrow is 40 ft from the stop line, a sec- upstream a distance D from the bottom of the letters of the ond turn arrow is placed such that the bottom of the arrow is TURN message. The distance D is based on the posted speed lined up with the upstream end of the lane line, a third turn limit as follows: 32 ft for 25 mph or less, 48 ft for 30 or 35 mph, arrow is placed halfway between the other two turn arrows, 64 ft for 40 or 45 mph, and 80 ft for 50 mph or more. and two ONLY word markings are placed at the halfway points between the three turn arrows. The design standards for Missouri state that two turn arrows are used for the first 200 ft of the turn lane and one additional The design standards for New York note that if the length turn arrow is placed for every additional 400 ft of the turn lane. of the full-width turn lane is less than 90 ft, only one turn arrow and ONLY word marking is provided. If the length of The design standards for Montana state that a second turn the full-width turn lane is between 90 and 135 ft, a second arrow and ONLY word marking are used if the average turn arrow and ONLY word marking is provided, with the annual daily traffic exceeds 5,000 or if the length of the turn distance between the top of the second turn arrow 25 to 65 ft lane is more than 150 ft. The distance between turn arrows (shown as 7.5 to 20 m) from the bottom of the letters of the and ONLY word markings in the turn lane is not specified, first ONLY word marking. If the length of the full-width turn but it is clear that each ONLY word marking appears just lane is between 135 and 250 ft, a second turn arrow and before the bottom of the turn arrow so that they function as a ONLY word marking is provided with the distance between single message. The spacing between successive sets of turn the top of the second turn arrow 65 ft (shown as 20 m) from arrows and ONLY word markings varies with the design the bottom of the letters of the first ONLY word marking. speed, and it is suggested that a spacing of approximately If the length of the full-width turn lane is between 250 and four times the character height be used on low-speed facili- 500 ft, a second turn arrow and ONLY word marking is pro- ties (45 mph or less) and up to ten times the character height vided, with the distance between the top of the second turn be used on high-speed facilities (50 mph or more). arrow 65 ft (shown as 20 m) from the bottom of the letters of the first ONLY word marking, and a third turn arrow and The design standards for Nevada note that if the length of ONLY word marking is provided, with the bottom of the the solid lane line is less than 55 ft, a single turn arrow is used ONLY word marking being 33 ft (shown as 10 m) down- and is placed such that the top of the turn arrow is 8 ft from stream from the start of the full-width turn lane. the stop line. If the length of the solid lane line is 55 to 95 ft, an ONLY word marking and a turn arrow are used, with the The design standards for North Carolina state that if the top of the letters of the ONLY word marking placed 8 ft from length of the full-width turn lane is less than 125 ft, a single the stop line, and the bottom of the turn arrow lined up with turn arrow is placed halfway between the stop line and the the end of the lane line (this is reverse reading with drivers end of the full-width turn lane. If the length of the full-width encountering the turn arrow first and the ONLY word mark- turn lane is more than 125 ft but less than 250 ft, two turn ing second). If the length of the solid lane line is more than arrows are placed in the lane with the top of the turn arrow 95 ft, an alternating series of turn arrows and ONLY word nearest to the stop line placed 50 ft from the stop line and the markings are used, with the top of the turn arrow nearest to other turn arrow placed such that the bottom of the arrow is the stop line placed 8 ft from the stop line and with the spac- lined up with the upstream end of the full-width turn lane. If ing between the bottom of subsequent turn arrows or ONLY the length of the full-width turn lane is more than 250 ft, three word markings being 32 to 80 ft from the top of the next turn turn arrows are placed in the lane with the top of the turn arrow or ONLY word marking. arrow nearest to the stop line placed 50 ft from the stop line, a second turn arrow placed such that the bottom of the arrow The design standards for New Hampshire provide specific is lined up with the upstream end of the full-width turn lane, layouts of turn arrows and ONLY word markings for the fol- and a third turn arrow is centered between the other two. lowing lengths of solid lane lines between the turn lane and Additional arrows may be used if the turn lane is long. the adjacent through lane: 100, 150, 200, 250, 300, and 350 ft. For a 100-ft lane line, an ONLY word marking and a turn The design standards for Oklahoma state that if the length arrow are used, with the bottom of the letters of the ONLY of the turn lane is less than 100 ft, only one turn arrow is used word marking placed 40 ft from the stop line, and the bottom with the top placed 20 ft from the stop line, and an optional of the turn arrow lined up with the upstream end of the lane ONLY word marking may be provided with the top of the let- line (this is reverse reading, with drivers encountering the ters 35 ft upstream from the top of the turn arrow. If the turn arrow first and the ONLY word marking second). For length of the full-width turn lane is 100 to 149 ft, a second

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11 turn arrow is provided with the top of the turn arrow 35 ft additional sets of turn arrows and ONLY word markings are upstream from the top of the letters of the ONLY word mark- provided. At unsignalized, non-stopping approaches, the ing. If the length of the full-width turn lane is 150 to 200 ft, solid lane line between the turn lane and the adjacent through the top of the turn arrow that is nearest the stop line is placed lane is extended and curved into the intersection until the first 30 ft from the stop line, an optional ONLY word marking conflict point is reached. may be provided with the top of the letters 55 ft upstream from the top of the turn arrow, and a second turn arrow is pro- The design standards for Virginia note that if the length of vided with the top of the turn arrow 35 ft upstream from the the turn lane is 300 ft or less, two turn arrows are provided top of the letters of the ONLY word marking. No informa- with the bottom of the turn arrow nearest to the stop line tion is given for turn lanes that are longer than 200 ft. located 50 ft from the stop line and the bottom of the other turn arrow lined up with the upstream end of the full-width The design standards for Oregon state that the tip of the turn lane. If the length of the full-width turn lane is more than arrowhead for the required turn arrow in a turn lane is 10 ft 300 ft, a third turn arrow is placed at the midpoint of the full- downstream from the upstream end of the full-width turn width turn lane. lane. A second turn arrow may be used and is placed such that the tip of the arrowhead is 10 ft from the stop line. If an The design standards for Wisconsin state that if the length optional ONLY word marking is used, then the second turn of the turn lane is less than 108 ft, only one turn arrow and arrow 10 ft from the stop line is required. ONLY word marking is provided, with the bottom of the let- ters of the ONLY word marking typically 20 ft downstream The design standards for Tennessee note that if the length from the upstream end of the full-width turn lane and the turn of the turn lane is less than 150 ft, only one turn arrow is used, arrow typically placed such that the top of the turn arrow is with the top placed 50 ft from the stop line. If the length of 20 ft from the stop line. If the length of the turn lane is 108 to the full-width turn lane is 150 to 200 ft, a second turn arrow 167 ft, two turn arrows and an ONLY word marking are pro- is provided with the bottom of the turn arrow 25 ft down- vided with the top of the turn arrow nearest to the stop line stream from the upstream end of the full-width turn lane. If typically placed 20 ft from the stop line, another turn arrow is the length of the full-width turn lane is more than 200 ft, placed such that the bottom of the arrow is lined up with the additional turn arrows may be equally spaced between the upstream end of the full-width turn lane, and the ONLY word two required turn arrows. marking placed halfway between the turn arrows. If the length of the turn lane is more than 167 ft, two sets of turn arrows The design standards for Texas note that two sets of turn and ONLY word markings are provided (with the bottoms of arrows and ONLY word markings are used in turn lanes that the turn arrows located 32 ft upstream from the top of the let- are 180 ft or more in length. The top of the turn arrow near- ters of the ONLY word marking), with the bottom of the let- est to the stop line is typically 32 ft from the stop line. The ters of an ONLY word marking placed 20 ft downstream from top of the letters of the ONLY word marking is placed 32 ft the upstream end of the full-width turn lane and the turn arrow upstream from the bottom of the turn arrow nearest the stop nearest to the stop line typically placed such that the top of the line. A second turn arrow and a second ONLY word mark- arrow is 20 ft from the stop line. ing are placed 32 ft apart at an unspecified distance upstream in the turn lane. The design standards for the District of Columbia state that markings in turn lanes start with a turn arrow, followed The design standards for Utah and West Virginia require by an ONLY word marking, and ending with an arrow near that both turn arrows and ONLY word markings are used the stop line, all of which fits within the 90-ft distance of the where a movement that would otherwise be legal is to be solid lane line between the through lanes. In longer turn prohibited. lanes, the markings start with a turn arrow, followed by an ONLY word marking, followed by another turn arrow, fol- The design standards for Vermont state that if the length lowed by another ONLY word marking, and ending with an of the turn lane is less than 100 ft, only one turn arrow and arrow near the stop line. ONLY word marking is provided with the bottom of the let- ters of the ONLY word marking lined up with the upstream The design standards for Puerto Rico note that two sets of end of the full-width turn lane and the turn arrow placed such turn arrows and SOLO messages are provided in the turn that the bottom of the arrow is 4 ft downstream from the top lane. The top of the turn arrow nearest to the stop line is of the letters of the ONLY word marking. If the length of the placed an unspecified distance from the stop line. The second full-width turn lane is 100 to 200 ft, a second turn arrow and set is placed such that the bottom of the SOLO message is ONLY word marking is provided with the top of the turn lined up with the upstream end of the full-width turn lane. arrow placed 4 ft from the stop line and the ONLY word marking placed such that the top of the letters of the ONLY The design standards for the city of Los Angeles state that word marking is 4 ft upstream from the bottom of the arrow. typically only one turn arrow is used and it is installed such If the length of the full-width turn lane is more than 200 ft, that the bottom of the turn arrow is lined up with the upstream

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12 end of the full-width turn lane. If the turn lane is longer than The design standards for Maryland state that the minimum 250 ft, a second turn arrow is placed at the midpoint of the configuration of turn arrows and ONLY word markings shall full-width turn lane. A turn arrow is only placed near the stop be an arrow-ONLY-arrow sequence, with an equal distance of line if required by the California DOT (Caltrans) on freeway 40 to 90 ft between the center of the ONLY word marking and ramps and other state highway intersections. the center in each direction of the next turn arrows. The center of the turn arrow nearest to the stop line should be approxi- The design standards for Tucson/Pima County, Arizona, mately 50 ft from the stop line. Section 3B.19 of the Maryland note that at least two turn arrows are placed in turn lanes. The supplement to the MUTCD has a chart that specifies (based on top of the turn arrow nearest to the stop line is typically placed a variety of speeds) how to add more turn arrows and ONLY 20 ft from the stop line. The bottom of the other turn arrow is word markings to the lane being dropped such that the first turn lined up with the upstream end of the full-width turn lane. If arrow encountered ranges from 375 ft from the stop line for a the turn lane is 108 to 200 ft in length, an ONLY word mark- prevailing (not posted) speed of 25 mph to 800 ft from the stop ing is placed halfway between the two turn arrows. If the turn line for a prevailing speed of 55 mph. lane is more than 200 ft in length, an ONLY word marking and a third turn arrow are placed at one-third points between The design standards for North Carolina state that two sets the two turn arrows, with the ONLY word marking placed of pavement markings (with each set comprised of two turn closer to the stop line than the third turn arrow. arrows and one ONLY word marking) are used in all dropped lanes. In each set, the ONLY word marking is placed halfway between the two turn arrows whose tops are placed 150 ft Use Versus Non-Use of Turn Arrows apart. In the first set, the top of the turn arrow nearest to the stop in Dropped Lanes (14 agencies) line is placed 50 ft from the stop line. In the second set, the top The design standards consistently are that the use of turn of the turn arrow nearest to the stop line is placed 350 ft from arrows in dropped lanes is required, as stated in Paragraph 14 the stop line if the speed limit is 35 mph or less, 400 ft from the of Section 3B.19 of the MUTCD. stop line if the speed limit is 40 to 50 mph, or 650 ft from the stop line if the speed limit is 55 mph or more. Use Versus Non-Use of ONLY Word Markings The design standards for Oregon specify that two turn in Dropped Lanes (14 agencies) arrows are required. The design standards for 10 agencies (FL, GA, IA, KS, MD, The design standards for South Carolina state that two NC, SC, TN, WY, and CLT) state that the use of ONLY word turn arrows, each accompanied by an ONLY word marking, markings in dropped lanes is required. are required. The design standards for Idaho and Rhode Island note The design standards for Wyoming note that two turn that the use of ONLY word markings in dropped lanes is arrows and an ONLY word marking are required. recommended. The design standards for the city of Charlotte specify that The design standards for two agencies (Pennsylvania and if the speed limit is 35 mph, a sequence of four turn arrows and Oregon) note that the use of ONLY word markings in two ONLY word markings is used in the downstream direc- dropped lanes is optional. tion as follows: a turn arrow, an ONLY word marking, two turn arrows, another ONLY word marking, and a turn arrow. Placement of Turn Arrows and ONLY Word The top of the turn arrow nearest to the stop line is placed 25 Markings in Dropped Lanes (9 agencies) ft from the stop line. The next two markings are placed such that the top of the turn arrow or ONLY word marking is 50 ft The design standards for Georgia state that the top of each from the bottom of the next downstream marking. The next ONLY word marking is separated from the top of the next three markings are placed such that the top of the turn arrow downstream turn arrow by 100 ft and from the top of the next or ONLY word marking is 100 ft from the bottom of the next upstream turn arrow by 50 ft. downstream marking. If the speed limit is 40 mph or more, the same markings as for a 35 mph speed limit are used, except The design standards for Kansas note that the tip of the that an additional turn arrow is placed upstream from the other arrowhead for the turn arrow nearest to the stop line is at least six markings such that the top of the additional turn arrow is 25 ft from the stop line. Spacing of alternating turn arrows 150 ft from the bottom of the next downstream turn arrow. and ONLY word markings (measured as the blank space between the bottom of one arrow or message to the top of the The design standards for the city of Tucson/Pima County next arrow or message) is 80 ft. The turn arrow nearest to the show that lane-reduction arrows and warning signs are used upstream end of the lane line is positioned such that the bot- to move through traffic out of the dropped lane before the tom of the arrow is lined up with the start of the lane line. turn lane markings are started.