ST9304-CS 950901Coppell, Texas 75019
P.O. Box 478
Coppell, Texas 75019
214-462-0022
September 1, 1995
Ms. Jill Schneberger, P.E.
Dallas County Public Works
411 Elm Street
Dallas, Texas 75202
RE: Beltline Road from Denton Tap to MacArthur (ST93-04)
Dear Ms. Sclmeberger:
The City of Coppell has again reviewed the plans submitted for Beltline Road and has the
following comments to offer:
1. Will the traffic signals at Moore and Mockingbird be upgraded with this project?
2. Conduits should be provided at all medians for irrigation and lighting.
3. In areas where there is adequate right-of-way, a four-to-one slope should be used.
In the area of Station 81+00 through 89+00, I am concerned about the long-term
stability of the road due to the substantial amount of fill, sometimes exceeding 20 + feet.
What special precautions or design changes are proposed to ensure the integrity of the
road?
,
Because of the amount of fill and the three-to-one slopes, you should require 95 percent
density both under the paving and in all areas where fill is being placed, i.e., fight-of-
way line to right-of-way line.
6. The inlet at Station 5 +06 should be relocated westward approximately 10 to 20 feet.
,
Several of the streets and/or driveways on the north side of Beltline have a fairly severe
grade break without any vertical curve. Please evaluate what can be done during the
design to provide a smoother transition. Has consideration been given to raising Beltline
Road in some of these areas?
8. Will the railroad crossing at approximately Station 39+00 be upgraded with this project?
Ms. Jill Schneberger, P.E.
September 1, 1995
Page Two
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10.
11.
12.
13.
14.
15.
16.
On the previous set of plans the toe of slope was provided along the north and south side
of the roadway. Why was that removed? Please provide it again on the plans.
Per the City of Coppell Streetscape Plan, the entire intersection of Moore Road with
Beltline should be brick pavers.
Based on my review of the ultimate and existing flood plain elevations, it appears as
though the section of Beltline Road between Station 78+00 to Station 81+00 is not
adequately elevated above the ultimate flood plain. The ultimate flood plain elevation
is approximately 463. Therefore, the minimum elevation of the roadway should be at
least 464. It appears the road should be raised. If that is impossible, then possibly a
berm could be constructed on the north side of Beltline Road to prevent water from
flooding across Beltline in a 100 year storm. The berm should be considered only as a
last resort.
Please evaluate the sight distance at the intersection of Northlake with Beltline.
The City has yet to see the bridge plans. However, the minimum low chord elevation
of the bridge should be at least 463. This is one foot above the ultimate flood plain
elevation.
Will there be any type of flood study provided for the bridge or the fill placed on the
portion of Beltline Road that is currently in the flood plain?
There are inlets proposed on the north side of Beltline at Mockingbird south of the
railroad tracks. It appears that there are no gutter transitions on the north side of the
inlets. This situation needs to be reevaluated to determine if the inlets can be shifted
southward to provide the proper transition.
Even though the City still has not received the drainage design, I have briefly looked at
the overall drainage information. I have several comments concerning that:
It appears that drainage basin B is discharging northward into an existing building.
Is this actually what is being proposed for the drainage? If so, this will not work.
I have concerns about how drainage in some of the areas will be picked up, such
as B3, C1, C17, etc.
Is the existing system on the east side of MacArthur adequate to handle the
drainage basin of J and K?
Ms. Jill Schneberger, P.E.
September 1, 1995
Page Three
There are several other comments throughout the plans that also need to be addressed. The City
appreciates the opportunity to again review these plans.
If you should have any questions concerning these comments, please feel free to contact me at
your convenience.
Sincerely,
Kenneth M. Griffin, P.E.
Assistant City Manager/City Engineer
KG:kb