City of Frisco Engineering Standards

Engineering Standards
Design
Speed
V (MPH)
(1)
(2)
(3)
TABLE 2.13: Sight Line Triangle Distances
Sight Distance by Lanes in Cross Section
L and R (ft)
2 4 (2) 6 (2)
25 280 (3) N/A N/A
30 335 N/A N/A
35 390 N/A N/A
40 445 N/A N/A
45 500 530 565
50 555 590 625
Source AASHTO’s 2011 A Policy on Geometric Design of Highways and Streets – Chapter 9.
Manual calculations of the procedures in AASHTO’s 2011 A Policy on Geometric Design of Highways
and Street s– Chapter 9
150 feet with approval by the Director of Engineering Services.
D. Traffic Control Devices – Any landscape requirements in the Engineering Standards, the
Subdivision Ordinance, the Zoning Ordinance, or any other City ordinance shall not interfere
with the placement, visibility or maintenance of traffic control devices under governmental
authority and control.
2.08 Frontage Road Design
A. Frontage roads are typically a pair of one-way roadways found adjacent to existing or planned
freeway or tollway facilities.
B. Frontage roads are considered Type A thoroughfares. Frontage roads for the Dallas North
Tollway shall be designed to the Type A standards set forth in this document. Frontage roads
along state highways shall follow TxDOT design guidelines.
C. Access to frontage roads shall also conform to the standards set forth for Type A thoroughfares.
In addition, the following access restrictions apply to frontage road design:
1. Exit Ramp Restrictions:
a. No driveway shall be located less than fifty feet (50’) in advance of the concrete curb
gore of an exit ramp, measured from the edge of the driveway.
b. No driveway shall be located less than four hundred feet (400’) beyond the concrete curb
gore of an exit ramp, measured from the edge of the driveway.
2. Entrance Ramp Restrictions:
a. No driveway shall be located less than two hundred feet (200’) in advance of the concrete
curb gore of an entrance ramp, measured from the edge of the driveway.
b. No driveway shall be located less than fifty feet (50’) beyond the concrete curb gore of an
entrance ramp, measured from the edge of the driveway.
Section 2 – Thoroughfare Design Requirements May 2012 Page 2-50