Freeport NIP(7.6)-CS020801Phone:
Jeff:
T H E C 1 T Y O F
COPPELL
Re: Sight Distance Requirements CC:
ENGINEERING DEPARTMENT
FAX COVER SHEET
To: Jeff Langston From: Teresa Turner
Fax: 972 361 -6800 Date: 8/1/2002
P.O. Box 478
255 Parkway Blvd
Coppell, TX 75019
Phone: (972)304 -3681
Fax: (972)304 -3570
Pages: 7 (including cover sheet)
Urgent ❑For Review Please Comment Please Reply IZI As Requested
Please see the attached section of The City of Coppell's Subdivision
Ordinance pertaining to sight distance requirements. Once you and your
landscape architect have had an opportunity to review the intersection of
Freeport Parkway and Creekview, contact me to discuss options.
If you have any questions, please feel free to contact me at 972 304-3681.
IF YOU DO NOT RECEIVE ALL OF THE PAGES PLEASE CALL (972) 304 -3679
"City of Coppell Engineering Excellence By Design"
DESIGN
SPEED
(mPb)
STOPPING SIGHT
DISTANCE (feet)
PAVEMENT
WIDTH
(b-b)
INTERSECTION SIGHT DISTANCE
(feet)
NEAR SIDE
FAR SIDE
M*
D *s
M*
Ds*
Ms
Ds*
30
200
200
28'
200
260
200
300
35
225
250
33'
240
325
270
370
41'
240
330
275
375
40
275
325
49'
275
350
305
425
45
325
400
49'
320
450
450
580
63'
320
450
450
580
50
400
475
2 -25'
350
500
500
650
2 -37'
350
500
500
650
1
1
i
1
J
1
1
1
1
1
1
1
1
1
1
M is minimum
D is desirable
SUBDIVISION REGULATIONS CITY OF COPPELL. TEXAS
APPENDIX C DESIGN CRITERIA AND STANDARDS
SECTION I STREETS AND ALLEYS
TABLE A -3
SIGHT DISTANCES
(SEE FIGURE A -1)
FOR DISTANCE ADJUSTMENTS DUE TO GRADE OF STREET USE TABLE A-4
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1S
SUBDIVISION REGULATIONS CITY OF COPPELL. TEXAS
APPENDIX C DESIGN CRITERIA AND STANDARDS
SECTION I STREETS AND ALLEYS
GRADE APPROACHING INTERSECTION
GRADE APPROACHING INTERSECTION
,r
CENTERLINE OF STREET /MEDIAN CURB
FAR SIDE
BACK OF CURB/EDGE OF PAVING
NEAR SIDE
LINE OF SIGHT
USE WITH TABLE A -3
Figure A -1; Sight Distance At Intersection
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SUBDIVISION REGULATIONS CITY OF COPPELL. TEXAS
APPENDIX C DESIGN CRITERIA AND STANDARDS
SECTION I STREETS AND ALLEYS
IMPROVED STREET WITH CURB AND GUTTER
I-
LL/
w
1
STREET
UNIMPROVED STREET WITHOUT CURB AND GUTTER
SEE FIGURE A -1, TABLES A -3 AND A-4 FOR INTERSECTION SIGHT DISTANCES
Figure A-5; Streeet Intersection Visibility Triangle
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SUBDIVISION REGULATIONS CITY OF COPPELL. TEXAS
IX
SECTION I STREETS AND ALLEYS
D. Intersection Visibility Obstructions
1. Visibility Requirements for Residential (Local) Street Intersections.
No fence, wall, screen, billboard, sign, structure, foliage, hedge, tree, bush,
shrub, berm, or any other item, either manmade or natural shall be erected,
planted or maintained in such a position or place so as to obstruct or
interfere with the following minimum standards:
a. Vision at all intersections where streets intersect at or near right angles
shall be clear at elevations between two and one -half (2 1/2) feet and
nine (9) feet above the average gutter elevation, except single trunked
trees within a triangular area formed by extending the two curb lines
from their point of intersection (see Figure A -5), forty-five (45) feet,
and connecting these points with an imaginary line, thereby making a
triangle. If there are no curbs existing, the triangular area shall be
formed by extending the property lines from their point of intersection
thirty (30) feet and connecting these points with an imaginary line,
thereby making a triangle. These requirements are in addition to those
shown in Figures A -1 and A -5 and Tables A -3 and A-4 of the
Geometric Design Standards to Thoroughfares.
2. Visibility Triangles for Non Residential (Collector and Arterial) Streets and
Drives.
The desirable minimum sight distances are based on the premise that
entrance maneuvers should not severely degrade traffic flow on an urban
street. They are, therefore, particularly applicable to arterial streets. Actual
sight distances provided at intersections should be much greater than these
minimum values if practical. Therefore, the following minimum sight
distance triangle that incorporates both plan and profile restrictions shall
also apply to visibility obstructions at intersections.
a. In the plan view, the horizontal clear area at the intersection of a
proposed street/drive shall be defined as being within a triangular area
formed by:
(1) A line that is on the centerline of the proposed street/drive,
beginning at the intersecting street's tangent of curb and
continuing for a distance of fifteen (15) feet back into the
proposed street/drive to the end point;
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(2) A line that is parallel to and five (5) feet out from the
intersecting street's curb, beginning at the centerline of the
proposed street/drive and continuing for a distance as prescribed
by Figure A -1 and Table A -3, to the end point; and,
A straight line that connects the end point of a.(1) (that is on the
centerline and fifteen (15) feet back into the proposed
street/drive) and the end point of a. (2) (that is the distance from
Table A -3, along and five (5) feet out from the existing street's
curb from the centerline of the proposed street/drive).
b. In the profile view, the vertical clear area shall be defined as the area
that is below a point that is nine (9) feet above the street gutter and
above a point that is two and one -half (2 1/2) feet above the street
gutter.
3. The aforementioned restrictions also apply to streets which do not intersect
at right angles, except that the triangle dimensions shall not necessarily be
minimum requirements. In such cases, the City Engineer or his designated
agent, shall have the authority to vary such requirements as necessary to
provide safety for both vehicular and pedestrian traffic.
(3)
4. R.O.W. Obstruction Outside the Visibility Triangles
a. Fences, walls, screens, billboards, signs and other structures shall
conform to the Comprehensive Zoning Ordinance of the City, as
amended, and to the Sign Ordinance of the City.
b. Foliage of hedges, trees, and shrubs in public rights -of -way shall be
maintained by the property owner adjacent to the right -of -way, such
that the minimum overhang above a sidewalk shall be seven (7) feet.
The minimum overhang above a street, alley or public driveway shall
be fourteen (14) feet.
5. Abatement
SUBDIVISION REGULATIONS CITY OF COPPELL. TEXAS
APPENDIX C DESIGN CRITERIA AND STANDARDS
SECTION I STREETS AND ALLEYS
The Chief Building Official or his authorized representative shall have the
authority to determine whether any such fence, wall, screen, hedge, tree,
bush, shrub, billboard, sign or structure, as erected, planted or maintained,
constitutes a public hazard or public nuisance in violation of the provisions
of this ordinance. Upon such determination, he shall cause to be issued a
written notice to the owner or lessee of the property demanding that said
owner or lessee abate said hazard or nuisance within ten (10) days of
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SUBDIVISION REGULATIONS CITY OF COPPELL. TEXAS
APPENDIX C DESIGN CRITERIA ERIA AND
AND Y A R DS
the date said notice is mailed. The C f the owner o lessee the the hazard
or nuisance upon the written request
and upon payment of reasonable charges for labor.
6. Exceptions
The provisions of this ordinance shall not apply to, or otherwise interfere
with, the following:
a. Placement and maintenance of traffic control devices under
governmental authority and control.
b. Existing and future screening requirements imposed by the City
Council of the City of Coppell.
c. Existing and future City, State and Federal Regulations.
7. Procedure for Variance
The City Council may allow variances to the terms of this ordinance.
E. Additional Streets and Alley Requirements
1. Streets and alleys shall be platted and constructed in accordance with the
Thoroughfare Plan of the Comprehensive Plan or other plans approved by
the City Council, and shall conform to the following requirements:
a. The subgrade on all streets and alleys shall be thoroughly compacted
and proof -rolled as required. Subgrade material with a plasticity index
of less than 6 or greater than 12 shall be modified with a minimum
30#'s per square yard of hydrated lime or cement stabilization.
Fill material when tested in accordance with ASTM D- 698ITHD T-99
shall be placed in 6 to 8 inch thick (loose) lifts compacted to 95 of
theoretical density with a moisture content at optimum to plus 4
In lieu of the above subgrade requirements, the recommendations of
a soils engineering firm familiar with local conditions may be
submitted for review. The approval of any deviation from the above
requirements will be made on a case by case basis by the City
Engineer.
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