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Northwest Dallas CountyFlood Control District
Status ReviewNorthwest Dallas County
Flood Control District
in
The City of Coppell
Dallas County, Texas
© December 2021
Texas Reg. No. F-928
KHA Project # 064490013
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Table of Contents
Section Page
I. EXECUTIVE SUMMARY .................................................................................................. 2
II. SCOPE OF SERVICES ...................................................................................................... 2
III. LIMITATION ................................................................................................................... 2
IV. OBSERVATIONS ............................................................................................................. 2
A. Sumps ...................................................................................................................... 2
B. Box Culverts under Riverchase Drive .................................................................... 19
C. Glory Holes ............................................................................................................ 20
D. Spillways ................................................................................................................ 22
E. Outfall to the Elm Fork of the Trinity River ........................................................... 27
F. General Observations ........................................................................................... 30
V. RECOMMENDATIONS ................................................................................................. 31
Appendix A Facility and Maintenance Summary ......................................................... 33
Appendix B Site Map .................................................................................................... 38
Appendix C Projected Maintenance, Engineering, and NPDES/TPDES Costs .............. 40
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I. EXECUTIVE SUMMARY
Kimley-Horn and Associates, Inc. (Kimley-Horn) was retained by the Northwest Dallas
County Flood Control District (District) to perform a status review of the District’s facilities
and structures. The District is generally located in and around the Riverchase Golf Course in
the City of Coppell, Texas (see Appendix B “Site Map”).
In general, all of the District’s facilities are functioning properly and are in good condition.
Kimley-Horn visually reviewed the status of all above ground facilities within the District
(intake structure, spillway structures, glory hole intakes, sump banks, swales, and outfall
structure). Visible storm drain outfalls along sump banks were also reviewed. Observation
of the performance of below grade structures was noted. However, the facilities below
grade (box culverts, headwalls, and storm drain piping between sumps) were not visually
reviewed for all sumps in this report because they are either submerged or buried and are
not accessible.
II. SCOPE OF SERVICES
Kimley-Horn is providing engineering services to the District. These services include:
1. Performing a site reconnaissance of the District’s structures and facilities.
2. Preparing a report identifying the condition of the District’s structures and facilities.
3. Updating the 5-year maintenance schedule.
4. Attending a board meeting to answer any questions the District has concerning this
report.
III. LIMITATION
This report was prepared for the District. All information within this report is confidential
and may not be reproduced or conveyed in any fashion without the expressed written
consent of the District and Kimley-Horn. This report was prepared using generally accepted
engineering practices and no other warranty is expressed or implied.
IV. OBSERVATIONS
The following are photographs and comments from Kimley-Horn's observations performed
on October 19th, 2021 and November 22nd, 2021. Refer to Appendix B “Site Map” for
locations of photographs and facilities described.
A. Sumps
Sumps with significant sediment accumulations have been identified. Sediment was
removed from Sump 11 in 2005. Sediment was removed from Sumps 9 and 10 in 2006.
Work to remove sediment from Sumps 2 and 14 was completed in 2007. During
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observations on October 19, 2021, sediment was being hydraulically dredged from Sump 13
and transferred into Sump 1A. The dredging was complete before the observations
performed on November 22, 2021.
In 2019, Riverchase Golf Course addressed erosion occurring at the storm drain outfall
headwall located along Sump 10. In-situ material was excavated around the existing
headwall and backfilled with clay-like material. Slopes adjacent to the outfall headwall
were armored with riprap rock.
Sloughing along the banks of sumps was evident at headwalls out falling into a number
of the sumps as well as at the intake structure in Sump 3A. Sloughing was mostly
observed in Sumps 1A, 2A, and 3A. Erosion has encroached on cart paths near Sumps 11
and 2A. Erosion behind headwalls was mostly observed at Sumps 1A, 2, 2A, 3A, and 14.
Stormwater levels were very high in 2007. Minor slope failures were noted along the
banks of Sump 3A in the 2007 report. Stormwater levels were very high in the spring
and summer of 2015, in the late fall of 2015 through early 2016, and again for multiple
months in 2018. During observations in October 2021 and November 2021, additional
signs of continued sloughing were observed.
Storm drain outfalls into the sumps were observed. Visual observation was performed
where outfalls were found and were accessible at the time of the review. Some storm
drain outfalls shown on record drawings were not found in the field. Erosion around
storm drain headwalls was observed. Minor sediment accumulation was noted in some
areas. Spalling of concrete on the headwall for outfall 8-A in Sump 8 was observed.
Aquatic vegetation was observed, but levels have diminished from levels observed
earlier in the year. Sump 8 and Sump 11 have significant aquatic vegetation and algae
present.
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Photograph 1
Sloughing along South Bank of Sump 1A
Photograph 2
Erosion behind Storm Drain Outfall 1A-A Headwall of Sump 1A
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Photograph 3
Erosion along North Bank of Sump 1A
Photograph 4
Dredging Discharge into Sump 1A (from Sump 13)
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Photograph 5
Sloughing and Erosion at Cart Path Along Southeast Bank of Sump 2A
Photograph 6
Sloughing Along West Bank of Sump 2A
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Photograph 7
Erosion Along Southeast Corner of Sump 2A
Photograph 8
Sloughing and Aquatic Vegetation along North East Bank of Sump 2A
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Photograph 9
Outfall 2A-A Headwall at Sump 2A
Photograph 10
Sloughing Along South Bank of Sump 3A
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Photograph 11
Sloughing along West Bank of Sump 3A
Photograph 12
Algae Observed at Sump 8
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Photograph 13
Concrete Spalling on Storm Drain Outfall 8-A Headwall on Bank of Sump 8
Photograph 14
Erosion along West Bank of Sump 9
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Photograph 15
Sloughing and Aquatic Vegetation on Banks of Sump 9
Photograph 16
Overview of Sump 10
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Photograph 18
Storm Drain Outfall Headwall on and Bank and Aquatic Vegetation of Sump 11
Photograph 17
Aquatic Vegetation at Sump 11
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Photograph 19
Sump 11 Overview
Photograph 20
Aquatic Vegetation/Algea in Sump 13
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Photograph 21
Aquatic Vegetation/Algae and Dredging Activities in Sump 13
Photograph 22
Storm Drain Outfall Headwall on Bank and Aquatic Vegetation in Sump 14
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Photograph 23
Storm Drain Outfall Headwall on Bank of Sump 14
Photograph 24
Box Culvert Headwall and Algae at Sump 14
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Photograph 25
Algae at Sump 2
Photograph 26
Storm Drain Outfall and Aquatic Vegetation at Southwest Corner of Sump 2
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Photograph 27
Erosion Behind Outfall 2-B at Sump 2
Photograph 28
Erosion Behind Headwall of Outfall 2-A at Sump 2
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Photograph 29
Overview of Sump 18
Photograph 30
Outfall Headwall at Sump 18
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Photograph 31
Sloughing and Erosion at Sump 18
B. Box Culverts under Riverchase Drive
Sediment accumulation was removed from the 5-8’×4’ box culverts (Line A, between
Sumps 2 and 14) and the 4-8’×4’ box culverts (Line B, between Sumps 9 and 10) in 2005
and 2006 and again in 2019. A storm sewer lateral connection protruding into the box
culvert was discovered and adjusted to be flush with the box culvert wall. In addition, an
area extending 10 linear feet beyond each box culvert headwall was also cleaned and
sediment removed.
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Photograph 32
Box Culvert Headwall at Sump 14
C. Glory Holes
Visible portions of Glory Holes appear to be in generally good condition. The Glory Hole
at Sump 13 appears to have a damaged grate and is significantly overgrown. The Glory
Hole at Sump 18 is in generally good condition.
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Photograph 33
Glory Hole at Sump 2
Photograph 34
Glory Hole at Sump 13 (Dislocated and Damaged Grate; Obscured by Vegetation and Debris)
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Photograph 35
Glory Hole at Sump 18
D. Spillways
All spillway structures were replaced in 2002 and 2004. No significant concerns were
noted during this observation and the structures appear to be in good condition. There
appears to be less vegetation surrounding the pipes and spillway in Gabion Spillway 2
and 4 than observed in the previous status review from November 11, 2020. Vegetation
was noted growing in close proximity to Spillway 3. Erosion was noted behind gabion
Spillway 6 and it appears to be larger than observed in previous review. Minor cracking
was observed in the concrete caps on all of the Spillways. All cracking appears to be larger
than previously observed. At Gabion Spillway 6, there was spalling observed on the
concrete cap.
In 2019, Riverchase Golf Course addressed erosion occurring at Gabion Spillway 4 at
Sump 3A and Gabion Spillway 5 at Sump 10. In-situ material was excavated 2-ft behind
the spillway. Filter fabric was installed and backfilled with clay-like material. Slopes
adjacent to the spillway were armored with riprap rock.
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Photograph 36
Gabion Spillway 1 at Sump 1A
Photograph 37
Crack in Concrete Cap on Gabion Spillway 1 at Sump 1A
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Photograph 38
Gabion Spillway 2 at Sump 14
Photograph 39
Gabion Spillway 3 at Sump 13 (Vegetation Growing on Gabions)
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Photograph 40
Gabion Spillway 4 at Sump 3A
Photograph 41
Crack in Concrete Cap on Gabion Spillway 4 at Sump 3A
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Photograph 43
Erosion Behind Gabion Spillway 6 at Sump 18 (Vegetation Growing on Gabions)
Photograph 42
Gabion Spillway 5 at Sump 10
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Photograph 44
Spalling on Concrete Cap for Gabion Spillway 6 at Sump 18
E. Outfall to the Elm Fork of the Trinity River
The outfall structure showed signs of some minor damage but continues to perform its
intended function. Minor cracking is evident in the headwall structure. Cracking was
noted in the outfall structure in previous reviews. Some erosion was previously
observed at the bottom of the spillway as it enters the river.
The damaged gabion mattress at the inlet structure was replaced as a part of the 2010
Miscellaneous Repairs project. Areas of erosion were also repaired at that time. Erosion
appears to be bigger behind inlet structure at Sump 3A compared to the last
observation on November 11, 2020.
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Photograph 45
Gabion Mattress Apron and Inlet Structure at Sump 3A
Photograph 46
Erosion Behind Inlet Structure at Sump 3A
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Photograph 47
Outfall Structure at the Elm Fork of the Trinity River
Photograph 48
Outfall Structure at the Elm Fork of the Trinity River
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F. General Observations
A previous problem with standing water in the TXU Right of Way adjacent to the
District’s facilities has been reported. This area is within the District boundary but is not
owned by the District. It is our understanding that the Riverchase Owners Association,
Oncor, and the City are ultimately responsible for maintenance of this area. The City has
proposed a trail project that will include improvements to the affected property. Kimley-
Horn is not aware of the status of this project.
As noted in previous reviews, sump bank erosion has been observed in multiple areas.
However, maintenance of the sump banks is not the District’s responsibility based on
our understanding of the original Declaration of Easements & Agreements document
recorded in Dallas County on July 29, 1987. Riverchase Golf Course personnel have
made efforts to address erosion maintenance at three District structures.
The intake to the box culverts crossing under MacArthur Boulevard and discharging into
Sump 11 is owned and maintained by the City of Coppell. Minor vegetation growth and
sedimentation was observed at the intake, but overall, the box culverts at MacArthur
Boulevard were in good condition.
Photograph 49
Box Culvert Under MacArthur Boulevard
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V. RECOMMENDATIONS
In general, the District's facilities are in good condition. However, both maintenance and
monitoring are advisable.
1. Sump Bank Maintenance: The 1987 Declaration of Easements & Agreements states in
Exhibit 7 that the golf course is responsible for the maintenance of the banks of lakes.
The “lakes” are referenced as sumps in this document. Riverchase Golf Course has
begun a maintenance program to address the sump bank maintenance needs.
Continued coordination regarding their maintenance program is advised.
2. Erosion behind Gabion Spillway 6: Eroded areas need to be filled and stabilized. It is our
understanding that the golf course is responsible for maintenance of the swales.
3. Glory Holes: Glory holes should be cleaned, grates repaired or replaced and maintained.
It is our understanding that the golf course is responsible for cleaning of the glory holes.
Future maintenance projects should consider replacing the glory hole grate at sump 13.
4. Aquatic Vegetation: Aquatic vegetation on Sumps 2, 8, 9, 11, 13, and 14 should be
addressed. Aquatic vegetation on Sumps 1A, 2A, 3A, 10, and 18 should be monitored.
5. Vegetation on Gabion Spillway Structures: Vegetation growing on spillway structures 2,
3 and 5 at Sumps 13, 14 and 18 should be addressed.
6. Cracking in Spillway Concrete Caps: Cracking should be monitored.
7. Spalling on Spillway Concrete Caps: Spalling should be monitored. Coordination with
Riverchase Golf Course regarding mowing around spillway concrete caps to prevent
future spalling is advised.
8. Outfall to the Elm Fork of the Trinity River: Eroded areas around the intake structure
and gabion mattress should be monitored.
9. Storm Drain Outfalls: As noted above, sump bank maintenance impacts the long-term
stability of storm drain outfalls. Sump bank erosion is impacting multiple headwalls.
Sump 1A, 2, 2A, 3A, and 14 headwalls that have significant erosion should be addressed.
There has been very little change in the condition of most of the storm drain outfalls
over the past several years. It is difficult to determine if and when the storm drain
outfalls will become unstable or fail, but if sump bank erosion continues, storm drain
outfalls will require attention at some point. Storm drain outfalls should be monitored.
At this time, no significant concerns have been observed related to visible storm drain
outfalls other than erosion of the sump banks around the headwalls. If sump bank
erosion leads to storm drain outfall damage, it is our understanding that Riverchase Golf
Course would be responsible for costs associated with those outfall repairs.
10. Box Culvert Under MacArthur Boulevard: Vegetation growth and sediment
accumulation at the box culvert intake should be monitored. If conditions worsen, the
City of Coppell should be notified of the maintenance need.
11. Sediment Accumulation Mitigation in Sumps: Current sediment levels in Sumps 2,8,9,
and 13 have been identified for removal. During observations, sediment was being
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transferred from Sump 13 to Sump 1A. A program to perform sediment removal has
been initiated.
12. Spalling on Outfall Headwall: Spalling on headwall should be monitored. Coordination
with Riverchase Golf Course regarding mowing around outfall headwalls to prevent
future spalling is advised.
13. Erosion Encroaching on Cart Paths: Erosion encroaching on cart paths should be
brought to the attention of Riverchase Golf Course so they can take any necessary
action they deem appropriate to address the issue.
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APPENDIX A
FACILITY AND MAINTENANCE SUMMARY
Northwest Dallas County Flood Control DistrictFacility Maintenance Inspection Summary
December 2021
Sump 2021 Comments Recommendations Activity Action Taken
1A Sloughing noted.Monitor progress of bank erosion. Monitor aquatic vegeation and algae.
Sediment accumulation noted in 2020 Sediment Report.
2 Sloughing noted. Aquatic vegetation/Algea noted.
Monitor progress of bank erosion. Coordinate removal of aquatic vegeation and algae.
Sediment accumulation noted in 2004 Annual Review and 2020 Sediment Report. Sediment removed in 2007.
2A Sloughing noted. Monitor progress of bank erosionSediment accumulation noted in 2020 Sediment Report.
3A Sloughing noted. Monitor progress of bank erosionSediment accumulation noted in 2020 Sediment Report.
8 Sloughing noted. Aquatic vegetation/Algea noted.Monitor progress of bank erosion. Monitor aquatic vegeation and algae.
Sediment accumulation noted in 2020 Sediment Report.
9 Sloughing noted. Aquatic vegetation/Algea noted.
Monitor progress of bank erosion. Coordinate removal of aquatic vegeation and algae.
Sediment accumulation noted in 2020 Sediment Report.
10 Sloughing noted. Monitor progress of bank erosionSediment accumulation noted in 2020 Sediment Report.
11 Sloughing noted. Aquatic vegetation/Algea noted.
Monitor progress of bank erosion. Coordinate removal of aquatic vegeation and algae.
Sediment accumulation noted in 2004 Annual Review and 2020 Sdiment Report. Debris noted at outfall in 2009.
Sediment removed in 2007. Debris removed in 2011.
13 Sloughing noted. Aquatic vegetation/Algea noted.
Monitor progress of bank erosion. Coordinate removal of aquatic vegeation and algae.
Sediment accumulation noted in 2020 Sediment Report. Sediment removed in 2021.
14 Sloughing noted. Aquatic vegetation/Algea noted.
Monitor progress of bank erosion. Coordinate removal of aquatic vegeation and algae.
Sediment accumulation noted in 2004 Annual Review. Sediment removed in 2007.
18 Sloughing noted. Aquatic vegetation/Algea noted.
Monitor progress of bank erosion. Coordinate removal of aquatic vegeation and algae.
Sediment accumulation noted in 2020 Sediment Report.
Box Culvert Recommendations Activity Action Taken
Riverchase North (5-8'x4')
Significant sediment previously noted. (30" maximum sediment observed) 48" pipe protruding into culvert. None.
Sediment accumulation noted in 2004 Annual Review. Sediment removed in 2006 and 2019.
Riverchase South (4-8'x4') Significant sediment previously noted. (30" maximum sediment observed) None.
Sediment accumulation noted in 2004 Annual Review. Sediment removed in 2006 and 2019.
MacArthur Blvd (2-7'x4') Minor sediment noted and debris noted. None.
Sediment accumulation noted in 2004 Annual Review.
Sediment removed in 2006 and 2019..
Glory Hole Recommendations Activity Action Taken
Sump 2 Minor debris collected on grate. Monitor debris on grate.
Addition of grate recommended in 2003 Annual Review. Grate cleaning recommended in 2009, 2015 and 2018.
Grate installed in 2004. Grate cleaning addressed in 2011. Grate cleaning addressed in 2016.Grate cleaning addressed in 2021.
1/7/2022
Northwest Dallas County Flood Control DistrictFacility Maintenance Inspection Summary
December 2021
Sump 13 Debris collected on grate.Dislocated and damaged grate. Replacement of grate.
Addition of grate recommended in 2003 Annual Review. Grate cleaning recommended in 2009, 2015 and 2018.
Grate installed in 2004. Grate cleaning addressed in 2011. Grate cleaning addressed in 2016.Grate cleaning addressed in 2021.
Sump 18 Minor debris collected on grate. Monitor debris on grate.
Addition of grate recommended in 2003 Annual Review. Grate cleaning recommended in 2009, 2015 and 2018.
Grate installed in 2004. Grate cleaning addressed in 2011. Grate cleaning addressed in 2016.
Spillway Recommendations Activity Action Taken
1 Minor cracking noted. Monitor cracking Damage noted in 2003 Annual Review. Structure replaced in 2004.
2 Minor cracking noted. Vegetation growing near face of structure. Monitor cracking; Monitor vegetation Damage noted in 2003 Annual Review. Structure replaced in 2004.
3 Minor cracking noted. Vegetation growing near face of structure. Monitor cracking; Monitor vegetation Damage noted in 2001 Annual Review. Structure replaced in 2002.
4 Minor cracking noted. Monitor cracking Damage noted in 2003 Annual Review. Structure replaced in 2004.
5 Minor cracking noted. Vegetation growing near face of structure. Monitor cracking; Monitor vegetation Damage noted in 2001 Annual Review.
Structure replaced in 2002. Hole filled and grading performed by Riverchase Golf in 2010.
6
Erosion noted behind structure. Minor cracking noted. Vegetation growing near face of structure. Minor spall noted.
Monitor cracking; Monitor vegetation; Monitor spalling: Coordinate filling and stabilizing of erosion. Damage noted in 2001 Annual Review. Structure replaced in 2002.
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Northwest Dallas County Flood Control DistrictFacility Maintenance Inspection Summary
December 2021
Outfall to the East Fork of the Trinity River Recommendations Activity Action Taken
Intake Erosion noted. Address erosion.Gabion deterioration and erosion noted in 2009 review.
Gabion and erosion repairs addressed in 2011.
Outfall Minor cracking at headwall/minor erosion. Debris piled in area of outfall.Monitor condition of outfall. Coordinate removal of debris. None.
Storm Sewer Outfalls to Sumps1,2,3
Recommendations Activity Action Taken
1A-A Apparent erosion at flowline. Continued visual observation. N/A N/A
2-A Apparent erosion at flowline. Visible erosion around headwall. Continued visual observation. N/A N/A
2-B Visible erosion around headwall. Continued visual observation. N/A N/A
2A-A Visible erosion around headwall. Continued visual observation. N/A N/A
2A-B Visible erosion around headwall. Continued visual observation. N/A N/A
8-A Minor erosion visible around headwall. Minor spall on headwall. Continued visual observation. N/A N/A
10-A Erosion addressed by Riverchase Golf. None. N/A N/A
10-B Not Found. N/A N/A
11-AMinor sediment accumulation at flowline. Visible erosion around headwall. Continued visual observation. N/A N/A
11-BMinor sediment accumulation at flowline. Visible erosion around headwall. Continued visual observation. N/A N/A
11-CMinor sediment accumulation at flowline. Visible erosion around headwall. Continued visual observation. N/A N/A
11-D Not Found. N/A N/A
11-E Not Found. N/A N/A
13-A Minor sediment accumulation at flowline. Continued visual observation. N/A N/A
13-B Apparent erosion at flowline. Continued visual observation. N/A N/A
13-C Minor sediment accumulation at flowline. Continued visual observation. N/A N/A
13-D Not Found. N/A N/A
14-A Visible erosion around headwall. Continued visual observation. N/A N/A
14-B Apparent erosion at flowline. Visible erosion around headwall. Continued visual observation. N/A N/A
14-C Apparent erosion at flowline. Visible erosion around headwall. Continued visual observation. N/A N/A
18-A Apparent erosion at flowline. Visible erosion around headwall. Continued visual observation. N/A N/A
18-B Not Found. N/A N/A
Notes:
1. Not all headwalls visible or accessible at time of observations.
2. Listing includes all storm sewer outfalls identified from record drawing investigations. Not all storm sewer outfalls were found in the field. Storm sewer outfall sediment observations were performed in 2013.
3. Erosion is associated with sump bank maintenance. It is our understanding that sump bank maintenance is not a District responsibility.
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Northwest Dallas County Flood Control District
Maintenance Summary*
December 2021
Year Project Annual Status Review Construction Cost
2002* 2002 Gabion Spillway Repairs Replaced Spillway Structures 3, 5, and 6 $76,100.00
2003 No Maintenance Projects $0.00
2004 2003 Drainage Structure Repairs
Replaced Spillway Structures 1, 2, and 4 and added grates to glory holes at Sumps 2, 13, and 18 $138,400.00
2005 2004 Sump 11 Sediment Removal Project Removed sediment from Sump 11 and cleaned box culvert under MacArthur Blvd.** $224,104.002006 2005 Sediment Removal Project**** Removed sediment from Sumps 9 and 10 and cleaned box culverts under Riverchase Dr. *** $197,407.40
2007 2005 Sediment Removal Project**** Removed sediment form Sumps 2 and 14 $91,876.50
2008 No Maintenance Projects $0.00
2009 No Maintenance Projects $0.00
2010 2010 Miscellaneous Repairs Project Initiated
Removed debris in Sump 11; cleaned grates at Glory Holes in Sumps 2, 13, and 18; repaired gabions and erosion at Intake to Outfall to the East Fork of the Trinity River $0.00
2011 2010 Miscellaneous Repairs Project Completed $172,392.00
2012 No Maintenance Projects $0.00
2013 No Maintenance Projects $0.00
2014 No Maintenance Projects $0.00
2015 No Maintenance Projects $0.00
2016 No Maintenance Projects $0.00
2017 No Maintenance Projects $0.00
2018 No Maintenance Projects $0.00
2019 Miscellaneous Repairs Project Completed
Riverchase Golf backfilled around existing headwall of Sump 10 and armored slopes with riprap; Riverchase Golf backfilled behind spillway at Sump 10 and armored slopes with riprap; Riverchase Golf backfilled behind spillway at Sump 3A and armored slopes with riprap. Sediment was removed from box culverts crossing Riverchase Drive at two locations. $48,993.00+
2021 Sump 13 Sediment Removal Completed
Removed sediment from Sump 13 and transferred to Sump 1A. Cleaned existing glory hole grates at Sump 2 and Sump 13. $48,900.00
Total $949,179.90
* Kimley-Horn does not have records regarding any maintenance projects prior to 2002.
** City of Coppell contributed $17,964.00 for box culvert cleaning.
*** City of Coppell contributed $82,692.90 for box culvert cleaning.
**** Split construction contract into two areas of work.
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APPENDIX C
PROJECTED MAINTENANCE, ENGINEERING,
AND NPDES/TPDES COSTS
Northwest Dallas County Flood Control District
5 Year Maintenance Schedule
2021-2026
(October through September)
Fiscal Year Recommended Maintenance Projected Construction Cost Projected Engineering Fees Combined Total 2021-2022 $0 $27,300
Miscellaneous Repairs/Sediment
Removal
$65,000 $20,000
Golf Course Coordination $0 $5,000
$100 $2,575
Totals $65,100 $54,875 Combined Total $119,975
2022-2023 Annual Status Review $0 $28,665
Miscellaneous Repairs/Sediment
Removal
$65,000 $20,000
Golf Course Coordination $0 $5,000
NPDES/TPDES Requirements $100 $2,704
Totals $65,100 $56,369 Combined Total $121,469
2023-2024 Annual Status Review $0 $30,098
Miscellaneous Repairs/Sediment
Removal
$65,000 $20,000
Golf Course Coordination $0 $5,000
TCEQ SWMP Updates $0 $18,000
NPDES/TPDES Requirements $100 $2,839
Totals $65,100 $75,937 Combined Total $141,037
2024-2025 Annual Status Review $0 $55,000
Miscellaneous Repairs/Sediment
Removal
$65,000 $20,000
Golf Course Coordination $0 $5,000
NPDES/TPDES Requirements $500 $10,000
Totals $65,500 $90,000 Combined Total $155,500
2025-2026 Annual Status Review $0 $33,108
Miscellaneous Repairs/Sediment
Removal
$65,000 $20,000
Golf Course Coordination $0 $5,000
NPDES/TPDES Requirements $100 $10,500
Totals $65,100 $68,608 Combined Total $133,708
5 Year Projected Costs $325,900 $345,789 $671,689
Annual Status Review
NPDES/TPDES Requirements
Note: These costs represent conceptual information only and are subject to change. The information listed above includes Northwest Dallas County Flood Control District anticipated potential costs only. Any costs
associated with sump bank maintenance are the responsibility of Riverchase Golf Course and are not included.
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