Lakes of C 1stP-CS 860422":NDM '"
- CONSULTING ENGINEERS, INC.
April 22, 1986
~DH ~: 84-3-003.D
N2. Prank Proctor
City Hanager
City of Coppell
616 Coppell Road
Coppell, ?X ?50%9
Re: Improvements to DeFore8t Road from MacArthur Blvd. east to its
terminus ·
Dear Frank:
Trlland Development Company has retained o~r firm to develop plans and
specifications for the Improvement of DePorest Road. We have completed a
preliminary deslgn for the project, and I believe that we are now ready for
presentation of our design to the citizens and City Council of Coppell.
Our analysis revealed a ~umber of constraints which Influenced the dest~
und ~ill directly affect the suitability and cost of the final roadway. These
constraints are as follows:
1. The right-of-way for DeForest Road ls currently 40 feet. This
right-of-way ts the result of a 30' pre-exlst~ng dedication,
available in some cases through prescription, and a dedication by
~en~ood ~omes and Dimension-Brooks Corporation In the platting of
~heir developments.
~uch of the road~a~ Is within the lO0-year floodplain of Denton
C~eek. AnF Permanent facility ~htch would provide uninterrupted
fire and police Protection should be elevated to at least the 100-
year ~ater surface elevation.
3. The fences existing to the north of DeForest Road canno~ be
disturbed.
A recent drainage study, completed by Carl Anderson and Associates,
Indicates ~hat the propertF north of DeForest ~oad can be reclaimed
from the ~00-year floodplain.
5. ?his property may not yet have attained its highest and best use.
There are severe local drainage problems along DeForest Road ~hich
cannot be exascerbated through planned Improvements to the road.
?. In deslgnin~ the Lakes of Coppell subdivision, our firm assu~ed that
the ultimate DeForest Road would be constructed at an elevation
obove the lO0-year floodplain. Therefore, In manF cases, the alleys
and lots adjacent to DeForest Road are at elevations and grades
Inconsistent with the existing elevation of DeForest Road.
8. The citizens currently residing along DeForest Road were assured by
Trlland that DeForest Road would be Improved In some manner concur-
rently with development ~lthln the Lakes of Coppell.
Three NorthPark/8800 N. Central Expwy./Suite $00/Dallae, Texas 7S231/(21¢) 73~-4741
Nr. Prank Proctor
April 22. 1988 '
Page 2
The aforementioned constraints, some of which are mutually exclusive.
have Introduced severe design problems which I fee! need to be considered.
Specifically:
I. The elevation of the 27' section of roadway above the lO0-year flood
level cannot be accomplished within a 40-foot right-of-way without
construction of retaining walla. Also, driveway accesa to the
roadway would neceesltate reconstruction of said driveways outside
of the 40 foot right-of-way.
2. To construct roadways without retaining walls would require 10' to
15' slope easements on the north side of DeForest Road.
$. The construction of the 2?-foot section would create adverse
drainage conditions and an lnaufficlent right-of-way for
construction of facilities to alleviate same.
4. The effects of elevating DeForest Road above the Denton Creek
Floodplain have not been determined through hydraulic analysi..
5. Should the area north of DeForest Road be redeveloped, a permanent
roadway greatkr than 27 feet wide would be required, it is
inconsistent with the City of Coppell'a policies to allow construc-
tion of concrete 'temporary roadwaya.'
Due to the problems that will be created by elevating and paving DeForest
Road, I recommend the following course of action;
1. Grind the existing DeForpst Road asphalt and apply a 2" thick
asphalt overlay, following essential existing profile grades.
2. Excavate the existing ditch north of DeForest Road, replacing and
providing driveway culverts where necessary to provide adequate
local storm drainage.
3. Trtland should escrow funds necessary to pave a 27' concrete section
on DeForest Road. These funds would then be available for the
City's participation, in the ultimate improvement of DeForest Road.
I would appreciate your comments and suggestions on this lingering
problem.
Sincerely,
NATHAN D. HALER
CONSULTING ENGINEERS, INC.
.S.
ND~/rp