City of Frisco Engineering Standards

Engineering Standards
c. Additional ROW shall be required adjacent to right-turn lanes so that there is a minimum
of ten feet (10’) of ROW from the back of curb.
d. Right-turn lanes will be delineated by using the City’s current Pavement Markings and
Markers standard details.
e. Minimum storage requirements are listed in Table 2.6. Storage requirements may
increase based upon actual and projected traffic demands.
f. A minimum tangent section of thirty feet (30’) shall be provided between the preceding
driveway or cross street curb return and the taper of a right-turn lane.
2. Taper Length – The taper specifications for right-turn lane entrance areas are specified in
Table 2.6. The variables used for the specification are shown in Figure 2.17.
Type of
Thoroughfare
On
TABLE 2.6: Minimum Right-Turn Lane Design Requirements
Type of
Thoroughfare
At
Turn
Lane
Width(s)
(ft)
Length of Taper Specifications (2)
Full-Width
Storage(ft) (1) R
Length(ft) 1 (ft)
R 2 (ft)
A A, B 11 225 150 515 515
B A, B 11 175 150 515 515
A, B
C, Residential
Collector
11 150 110 280 280
A, B D, E, F, G 11 100 110 280 280
TxDOT Road A,B,C,D,E,F,G See TxDOT’s Roadway Design Guide and Specifications
Frontage Road A,B,C,D,E,F,G
Apply Type A Thoroughfare specifications to Dallas Pkwy
Apply TxDOT specifications to SH 121 and US 380
1. Measured from the intersecting thoroughfare face of curb.
2. No driveways are permitted within the taper area.
Lane Width
R2
R
1
Street or
Driveway
Storage Length
Length of
Taper
Tangent
Section
FIGURE 2.17: Typical Right-Turn / Deceleration Lane Dimensions
Section 2 – Thoroughfare Design Requirements May 2012 Page 2-26