DR9201-CS 920303 .MEMO
TO: Steve Goram, Director of Public Works
FROM: Kenneth M. Griffin, P.E., City Engineer
SUBJECT: Howell/Bullock
DATE: March 3, 1992
I have prepared a general layout of the proposed drainage ditches on
Howell and Bullock. Because of the need to drain these streets, the
existing ditch running south of the railroad tracks and north of the
subdivision will also need to be graded to the existing wye inlet near
Denton Tap Road.
Your specifications indicate that the contractor has to maintain a 0.5%
slope on these ditches. However, based on the existing elevations in the
field, it is impossible to maintain a 0.5% slope on the graded ditch for
the entire length of the grading. To maintain a 0.5% slope coming from
the wye inlet back up the streets, the last three or four hundred feet of
each of the ditches would be basically flat. If you started your 0.5%
slope at the up-stream end, the last six to eight hundred foot of the
ditch, basically the section north of the subdivision, would be flat. I
have tried to generate a slope on the ditches that would maximize the
slope on all five ditches. The minimum slope for this proposed grading is
0.33% and the maximum slope is 0.48%. I have concerns even with these
slopes because of the distance between the asphalt and the property line.
The slope creates cuts of two feet in some places. To maintain a three to
one slope, you would need approximately fifteen to twenty foot to put this
ditch in, depending on the difference in the current flow line and the
edge of the roadway.
I have walked this project and noticed several improvements along the
street section where the ditch would need to be graded. Also, I'm not
sure if any thought was given to the existing utility services to the
houses. The grading of the ditch to maintain some flow to the north would
most likely necessitate the relocation of these utility services. Even if
it is physically possible to grade the ditches as shown, it could be
difficult for the adjacent property owners to maintain them because of the
flat slope and the fact that they will be susceptible to silting in.
During my field investigation, I noticed that there is standing water in
the alley near the north end of the subdivision. Was there any thought
given to grading, either all or a portion of the alley, at this time? I
also noticed that the existing location of the ditch on Howell Street at
the north end does not appear to be contained within a drainage easement.
The plats that we have on record for this area do not indicate that a
drainage easement was ever dedicated in that area.
However, as you requested, I have provided a general layout of the
location of the ditches with a maximized slope on all the ditches.
If you have any questions, please contact me at your convenience.
10 FOOT D~AINAGE EASEMENT
BEING 0.0251 acres of land situated in the City of Copse11, Dallas County Texas
out of the J. S£m~ons survey, abstract No. 1296 and being a part of the 15.03
acres tract conveyed by deed to William S Wright Lot 9 Howell Drive recorded in
volume 80016, Page 886. Deed records of said county tract being further
described as follows:
BEGINNING at the southwest corner of tract as recorded in volume 80016, Page 886;
THENCE, North 14 degrees 58 minutes East 109.20 feet;
THENCE, North 75 degrees 02 minutes East 10.0 feet;
THENCE, South 14 degrees 58 minutes West 109.20 feet;
THENCE, South 75 degrees 02 m£nutee West 10.0 feet; having a radius of 50 feet
to the Point of Beginning and containing 0.0251 acres or 1092 square feet of land
more or Ieee.
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