Item 9C - MemoItem 9C
CITY OF
SOUTHLAKE
MEMORANDUM
March 3, 2026
To: Alison Ortowski, City Manager
From: Lauren LaNeave, Interim Director Public Works
Subject: Approve an agreement with Apex Concrete Construction Inc.,
for the repair and replacement of the retaining wall located on
the eastbound side of FM 1709 (W Southlake Boulevard) near
the intersection at 1299 W Southlake Blvd in an amount not to
exceed $200,500.
Action
Requested: Approve an agreement with Apex Concrete Construction Inc.,
for the repair and replacement of the retaining wall located on
the eastbound side of FM 1709 (W Southlake Boulevard) near
the intersection at 1299 W Southlake Blvd in an amount not
to exceed $200,500.
Background
Information: In February 2025, a vehicular accident damaged a modular
block retaining wall located along eastbound FM 1709 just
east of Waterford Drive. Subsequent record reviews
completed during summer 2025 confirmed the wall is a City -
owned asset constructed as part of a TxDOT sidewalk project.
Following evaluation of the damage and existing wall
conditions, staff determined that full replacement is necessary
to restore long-term structural stability and address underlying
drainage deficiencies.
Following confirmation of ownership, staff began coordinating
directly with Farmers Insurance to recover the cost of repairs.
The City obtained an initial repair estimate totaling
approximately $157,669. This estimate reflected a one -for -
one replacement consistent with the existing wall design and
was prepared to establish a comparable replacement cost for
insurance recovery purposes. The estimate accounted for
both the direct impact location and displacement that
propagated along adjacent portions of the wall following the
collision.
Page 1 of 4
Item 9C
To document the extent of damage and establish an
appropriate long-term repair strategy, the City retained
Teague, Nall & Perkins (TNP) to perform a forensic
engineering evaluation. The assessment confirmed that while
the vehicular impact damaged approximately 36 feet of wall,
broader drainage deficiencies, hydrostatic pressure
conditions, wall rotation, and structural limitations existed prior
to the collision and extend along the entire wall length. The
engineer concluded that isolated repairs would not resolve
underlying stability concerns and recommended full
replacement incorporating improved drainage and structural
measures.
Based on these findings, staff revised the project approach
from a like -for -like reconstruction to a replacement solution
that incorporates engineering -recommended improvements
addressing drainage performance and long-term structural
reliability. Continued delay in reconstruction could allow
ongoing wall movement and drainage issues to worsen,
increasing future repair costs and potential risk to adjacent
public infrastructure.
The selected replacement approach consists of construction
of a cast -in -place reinforced concrete retaining wall, including
demolition and removal of the existing modular block wall,
installation of a reinforced concrete wall with spread footing,
incorporation of drainage materials and fabric, traffic control,
utility coordination, and associated site restoration activities.
To maintain corridor visual continuity, the new wall will include
a form liner and stained finish that provides a masonry
appearance similar to the existing block wall while delivering
improved durability and reduced long-term maintenance
needs. This approach is consistent with the engineering
recommendations to address long-term structural stability and
drainage deficiencies identified in the forensic evaluation.
Page 2 of 4
Item 9C
Financial
Considerations: Apex Concrete Construction has provided an estimate for the
work as shown in Table 1 below.
Table 1: Estimate Breakout
Wall Removal and Replacement
• demolition, excavation and
disposal of existing wall,
• construction of the reinforced
concrete wall system,
• drainage improvements,
• traffic control, tree root
pruning, utility bracing,
• and architectural treatments
Contingency (10%)
Total Council Authorization
$182,239
$18,261
$200,500
This agreement will be funded using available General Fund
Capital Improvements Program (CIP) residuals, which will not
impact ongoing or currently funded CIP projects.
Farmers Insurance initially issued payment of $5,751.26
based on an incorrect site assessment indicating that the wall
had already been repaired. The City disputed this
determination, as the wall remained in a damaged condition.
After escalation and a second inspection at the correct
location, Farmers issued an additional payment of $19,028.82
on November 26, 2025. This amount reflects the insurer's
determination for repair of only the visibly displaced impact
section. The driver's policy limits are insufficient to cover the
full cost of replacement.
The City will continue pursuing reimbursement from Farmers
Insurance for the portion of damages attributable to the
vehicular impact while allowing construction to move forward
to restore long-term infrastructure stability and public safety.
Strategic Link: Focus Areas — Infrastructure and Development
Financial Objectives: F2 — Investing to provide & maintain
high quality public assets.
Business Objectives: B2 — Collaborating with select partners
to implement service solutions.
Page 3 of 4
Item 9C
Citizen Input/
Board Review: While no formal community engagement has been
undertaken for this agreement, the City has coordinated with
the Stonelakes HOA over the past several months while
working through insurance coordination and repair planning.
Legal Review: The City Attorney has reviewed and approved the original
contract with Apex Concrete Services, Inc..
Alternatives: City Council may deny approval or direct staff to pursue an
alternative option.
Supporting
Documents: Attachment A: Apex Quote
Attachment B: TNP Forensics Report
Attachment C: Location Map
Staff
Recommendation: Approve an agreement with Apex Concrete Construction Inc.,
for the repair and replacement of the retaining wall located on
the eastbound side of FM 1709 (W Southlake Boulevard) near
the intersection at 1299 W Southlake Blvd in an amount not
to exceed $200,500.
Staff Contacts: Lauren LaNeave, Interim Director Public Works
Jack Thompson, Deputy Director of Public Works Operations
Jeff Ginn, City Engineer
Page 4 of 4
ATTACHMENT A
Apex Concrete Construction Inc
Grapevine, TX 76099
817-454-1995
Fax 817-337-8958
Name / Address
City of Southlake, Texas
Public Works
Attn: Julio / Jeff
Ship To
1709 Retaining Wall
@ Stonelakes
Estimate
Date
Estimate #
2/20/2026
1 192
Project
Qty
Item
Description
Rate
Total
Retaining wall/1709 @ Stonelakes
994
misc
Item # 14-1 General Labor including required equip. and
140.40
139,557.60
labor
Remove and disposal of the existing wall , and backfill
material. Excavation and haul off.
Provide a concrete reinforced wall 36 in lit x 6 in width x
306 ft long with a 4 ft spread footing .Include drainage,
gravel and fabric .
63
misc
Item # 14-1 General Labor including required equip. and
140.40
8,845.20
labor (Acid stain and seal one color)
138
misc
Item # 14-1 General Labor including required equip.
140.40
19,375.20
(add form liner including color)
72
misc
Item # 14-1 General Labor including required equip.
140.40
10,108.80
(Bracing for 2 power poles)
1 1
misc
Item # 14-1 General Labor including required equip. and
140.40
1,544.40
labor (Root prune 4 trees)
20
misc
Item # 14-1 General Labor including required equip.
140.40
2,808.00
(Traffic control on major thoroughfare)
Total $182,239.20
ATTACHMENT B
� tnp
Southlake Blvd. Retaining Wall Forensics Assessment
Memorandum
To:
City of Southlake
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From:
Joel Darr, P.E. (TNP)
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CC:
Jonathan Bengfort, P.E. (TNP)
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Date:
February 5, 2026
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RE:
Southlake Blvd. Retaining Wall Forensics Report
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Introduction
Teague, Nall & Perkins (TNP) conducted a visual inspection and evaluation of the retaining wall on the
south side of W. Southlake Blvd. (FM Highway 1709) between Waterford Dr. and Stone Lakes Dr. in
Southlake, TX on Thursday, January 15, 2026. Attendees on site included Joel Darr, P.E. and Emilia
Castillo.
The purpose of this investigation was to determine the extent of damage, what portion of this damage
was caused by vehicular impact, as well as appropriate repair/remediation recommendations. The
findings in this report are based upon visual observations and field measurements obtained during the
site visit, along with information obtained from record drawings and pictures provided by the City of
Southlake. The conclusions and recommendations presented in this report were developed in
accordance with generally accepted engineering practices and reflect conditions observed at the time
of inspection. Changes to those conditions could alter the recommendations.
Observations and Findings
Record Drawings, Recent Photos, & Google Street View
Prior to conducting an inspection, TNP reviewed the record drawings, recent photos provided, and
historical Google Street View images which indicated the following details and deficiencies:
Record Drawings:
• Precise height and length dimensions of the Modular Block Retaining Wall were not included in
the plans. Our assumption is the contractor developed a wall profile that would meet the grading
plan requirements.
• The `Modular Wall Section' on the Retaining Wall Details sheet states that the geogrid is utilized
"if necessary, as per manufacturer".
Recent Photos:
• Damaged modular blocks, dislodged blocks, and blocks that toppled off can be seen in two
different areas of the wall in the photos provided.
• There is a break in the running bond pattern in the blocks at the wall PI near both ends of wall.
Blocks on either side of these Pls have separated from each other.
• The photos indicate that the wall system has rotated toward the sidewalk in various areas along
the length of the wall.
Google Street View Images:
• TNP reviewed Google Street View images of the subject wall taken from 2011 to 2024. While
the amount of movement could not be measured from these Street View images, it was apparent
that some degree of wall rotation had taken place as far back as 2013. Evidence supporting this
tn p Southlake Blvd. Retaining Wall Forensics Assessment
conclusion is that the 2013 image showed open joints at the PI's near the wall ends, just as in the
recent photos provided by the city.
In several other Street View photos along the length of the wall, the wall did appear to be
rotated toward the sidewalk when compared against nearby features assumed to be plumb
(utility poles, for example) as far back as 2014.
Some historical Google Street View images showed areas of the wall which appeared to be
discolored due to the presence of water in the backfill. Also, as the wall aged, many of the
modular blocks became discolored in these same areas (likely due to frequent moisture and
growth of algae or moss). This indicates a potential additional hydrostatic load that the original
wall may not have been designed for.
1 /15/2026 Inspection
During the inspection, TNP noted the following additional findings to the Record Drawings, Recent
Photos, and Google Street View Images noted above:
• Damaged modular blocks, dislodged blocks, and blocks that toppled off at two areas of the wall
were confirmed. See Photos 1-3 in the Forensic Inspection Photo Log.
• The impact damage was measured to be a length of 36'. See Photo 4 in the Forensic Inspection
Photo Log.
• A 2" gap was measured at each PI near the beginning and end of wall. See Photos 5-6 in the
Forensic Inspection Photo Log.
• The top of wall has rotated toward the sidewalk between 3° to 25' from vertical.
• Individual modular blocks measured 18" wide by 8" in height.
• Utilizing the sidewalk as datum, the exposed maximum wall height measured 3'-3" and the
minimum exposed wall height measured 2'-4" at face of wall.
• Overall length of the wall measured approximately 312'-6".
• Dislodged blocks that exposed the back of wall revealed areas without structural geogrid
present and interfering tree roots. See Photo 7 in the Forensic Inspection Photo Log.
• Water runoff was observed at various areas along the sidewalk that appeared to be seepage
from the bottom of the wall. Water did not appear to drain through the "Lateral Subgrade
Drain" shown on the As -built. See Photos 6, 8, and 9 in the Forensic Inspection Photo Log.
• The soil at the top of the slope above the wall exhibited heavy saturation with several ponding
areas. Well Water signage and a main water shut-off valve cover were found where heavily
saturated soil was observed. See Photos 10-14 in the Forensic Inspection Photo Log.
• Trees and utility poles located in the slope behind the wall measured a 40 to 60 rotation toward
the sidewalk.
Conclusions and Recommended Follow -Up Actions
Opinion of Probable Cause
• The impact from the vehicular collision damaged and dislodged isolated blocks in a 36 foot
long section of the wall. Vibrations from this impact likely exacerbated the loading from the
backfill which may have caused a localized increase in the amount of rotation exhibited by the
wall near the impact location.
It is TNP's opinion that several factors contributed to the wall's rotational failure.
o Poor drainage: the presence of a drainage system in the record drawings indicates
that the original designer likely assumed a drained condition behind the wall. However,
the presence of standing water and saturated soil in the backfill, water flowing across
2
tn p Southlake Blvd. Retaining Wall Forensics Assessment
the sidewalk, and dry underdrains are evidence that the wall is actually experiencing
an additional hydrostatic load.
o Wall design: without layers of geogrid between the layers of blocks, this wall is
classified as a gravity wall. Using geogrid would have provided a more robust design
with larger Safety Factors.
o Vegetation: it is likely that the tree roots contributed to the drainage problems. Roots
may have compromised the geotextile fabric and allowed fines from the backfill into
the gravel drainage system. It's also possible that roots may have grown into the
underdrain itself, preventing it from performing properly.
The limits of these issues extend along the entire wall length. Based on available data, these
issues were present prior to the vehicular collision.
Recommendations
• Option 1: replace the entire wall with a similar modular block wall, but provide geogrid for
additional wall stability.
o This would provide a similar aesthetic to the existing wall, but would require substantial
excavation and earthwork to place geogrid in the backfill. This would likely require
tree replacement and utility coordination.
• Option 2: replace the entire wall with a gravity wall, which would use larger blocks to provide
wall stability.
o This option would change the look of the wall (using bigger blocks), but would require
less earthwork and could reduce impact to existing trees and utilities behind the wall.
• Option 3: replace the entire wall with a cast -in -place concrete "sidewalk wall".
o This option would require the least amount of earthwork and would minimize impacts to
existing trees and utilities behind the wall. Form liners could be used on the face of wall
to provide options for the wall's appearance. This option would likely be more
expensive than either modular block wall option because it would also require
demolition and replacement of the sidewalk.
• All options would also require the city to:
o Determine the cause of the water pressure built up behind the wall and repair this
underlying issue prior to beginning new construction.
o Demolish the entire existing wall.
o Remove existing vegetation and backfill or sidewalk as required.
o Provide adequate means of drainage behind the new wall.
ATTACHMENT C
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