Coppell Greens 1-CS020503May 3, 2002
Public Works Department - City of Coppell
ATTN: Per Birdsall
North Service Center
732 DeForest Rd.
Coppell, TX 75019
RE: Coppell Greens Subdivision
Dear: Per Birdsall
Thank you for taking the time to investigate the drainage and silt concerns that I brought to your attention
on April 11, 2002. As stated in out conversation on Tuesday, April 30, there are many problems that the
storm water run off from the Highpoint Oaks Development, located to the North of Coppell Greens in
Lewisville. It has not only created problems that my neighborhood is attempting to deal with but also
individual houses, and now I believe for the Storm Water System in Coppell.
I originally contacted you regarding the amount of silt that I believe to be being dumped in the cities
drainage system. The enclosed pictures detail out why I believe this to be happening first behind my
residence and later in the neighborhood. The first photos originate from the retaining wall in Fallkirk
Court. The majority of the wall resides in the back yard of 848 and crates problems for my property at 844
Fallkirk Court. 848 has flooded as recently as this month due to the abundance of water. I flooded less
than a year ago due to the drainage from the High Point Oaks Development washing silt and grass down to
the fence preventing the flow underneath resulting in my back quarter of my home to be flooded.
Recently the developer was asked to install a Storm Drain through the site for the development that the
Household Building on the first phase of that development sits on and also because the street that crosses
through the development continued to sink and collapse. I contacted the City of Lewisville regarding the
work being done because of the problems that I had been having as well as the neighborhood. I was told
that the site was to be brought back to it's elevation prior to the drain being added and that they were to be
correcting the problems with their erosion control. I have plans of their site, erosion control plan, and the
Storm Water Pollution Prevention Plans as provided to the city and they have not been and are currently
not complying with those plans.
The following are some of the issues as they involve my property and then the neighborhood.
· The Fallkirk Court retaining wall wash out is increasing with each storm despite the addition of a
trench/swale when the drainpipe was back filled. This wall has both horizontal and vertical cracking
and voids behind it as I have observed. The developer was to fix the channeling of water behind the
wall, fill the voids in the wall and fix the fence that sit directly behind the wall since it was caving in
due to the voids. The developer only dumped dirt in a mound on top of the wall attempting to build a
trench down the side. The trench has actually made the problem worse. It has caused drainage down
the backside of all of the homes and channeling water towards the back of the retaining walls creating
a detention area that is resting behind the wall due to some of the voids giving away. In my experience
it is only time before this causes the wall to completely give away flooding not only 848 Fallkirk Court
but also my home, the neighboring homes and the City Street with mud and debris. This trench has
also affected the drainage swale filling it before it goes into the backyard at 854 Applecross Court.
The silt fence behind 844 Fallkirk Court has been placed with aggregate and to an aggregate flume
under the fence draining that water into the new drainage swale that was added, again dumping more
water into the detention area now created behind the retaining wall.
There has been a two to three feet elevation increase of the site where the storm drain was put in place.
This site was to be put back to its original elevation prior to the utility work performed on it. This
obviously was not done. None of the site dirt created from the placement of the storm drainpipe was
hauled away. There would have been at least a ten-percent haul off due to only being able to reach a
ninety-pement compaction from the original compaction of the soil not including the spoil from the
dirt not replaced due to the storm pipe and rock being put in
This dirt is contributing to more water and silt draining down the site. Once finished the site should
not have been left raw, but should have been replanted to keep erosion from occurring.
The silt fence on the top of the hill has been improperly installed. The fence should have been buried
one foot into the ground; instead, they have piled dirt up on the edge making it appear to be installed
correctly. This is causing the water to flow under the fence or possibly tunnel under to cause the wash
out on the side of the hill.
Behind 850 and 854 Applecross Court, the hill is being eroded away, not only from water running over
it but there is also a tunneling effect that could be dangerous for people to be walking on it. Not only
is the Coppell Greens area being filled with an abundance of silt but also it is beginning to filter into
the homeowner's lots
The entire drainage valley for the hill has been filled with silt; therefore, the berms that have been built
within it are useless. This is resulting in more, if not all of the erosion material to be washed down
throughout the green belt area. This has resulted in an overflow of silt material in the drain pipes that
lead to our pond which is suppose to be - 10-foot deep according to the City of Coppell final plat plan.
Coppell Greens Berms at one time were deep and would have prevented the flow of the water from
reaching the sidewalks and channeling into the correct drainage paths but due to the development
above they have been filled causing the water to find a new path. The berms and erosion control plan
that I have obtained for the Highpoint Oaks Development have not been properly installed and due to
heavy rains have not been maintained in over a year. Many of these berms are broken and are also
filled with silt materials causing an overflow into Coppell Greens and the City Storm Drains.
There is also drainage from the site reaching Denton Tap Road. There is a manhole that has sunk at
least 6" due to the water and traffic driving over it. I am not sure if this is on the City of Coppell's side
or not.
Lastly taking you through the pictures and tape that I have submitted to you
Pictures: Please refer to the map for a detail as to where these pictures are being shot.
1. 848 Fallkirk CT. retaining wall after the rain on April 7th has slowed to a drizzle. The rain the
weekend before flooded this residence. Note the amount of water attempting to push through the wood
fence.
2. An 848 and 844 Fallkirk CT. show how the water flows down the hill into the swales and starts to run
around my home.
3. Back corner of 844 Fallkirk Court (my home) and where the flooding occurred last year and the swale
around the home. This swale is also being filled with water coming down the hill in my back yard as
well as the drainage from Denton Tap Road. All of this water brings my home closer and closer to
flooding again.
4. Water rushing into the Front Yard of 848 and along side of my home 844. Notice the bubbling/rushing
effect under the fence. Water is being detained behind the fence. Remember this is after the rain has
slowed.
5. Enlarged picture of 4
6. Water dumping into the street in the front of my home. The swale to the left in the picture that can not
be seen but is running with the same velocity out the other side of my yard with the same amount of
silt.
Enlarged picture of 6
Begins the tale of the silt the city is obtain from the Highppoint oaks due to their erosion control
measures not being in place and the amount of silt and water that is effecting the neighborhood.
9. The water and silt rushing down into the sidewalks and into the city drainage instead of into the area
pictured in 8. Again due to the silt filling our erosion control and Highpoint Oaks not fixing and
controlling theirs.
10. Another view of 9.
11. About an hour after a major ran the water and silt still flowing from High Point Oaks. If you look to
the left where the red arrow is this is pointing at where the hill is sloughing off into the channel. Note
that this was fixed only a month ago and again is falling into the channel. Previously to it being fixed
it had completely collapsed, as you can see the area that has been reworked.
12. Water and Silt continuing down the sidewalks from #11.
13. Water and Silt should be channeling into the inlet indicated by the arrow and under the sidewalk into
the area seen in #14.
14. Water and silt and hour later still dumping into the city drainage.
15. The correct path of what should be a normal, virtually siltless flow of water.
17. Pond that receives the overflow but has filled almost to compacity with silt causing overflow into the
other side of the neighborhood as shown in #16.
16. Water flowing from pond. Still containing silt then flows under the neighborhood and 113 Turnberry
to spill out into the neighboring development with another silt build up. This brings concern that the
drainage system that goes under the neighborhood and that particular home and could cause damage to
these homes.
Tape:
Shows the drainage on a different day similar to the progression of Photos 8-16 down the gorge into what
should be the pond but ends up in the sidewalk and the city storm system due to all of the berms being
filled with silt. It then shows the pond and the amount of what seems like water pushing through. The
majority of that pond is now silt resulting in the high appearance.
Again, thank you for your time already spent on this. If you would please inform me as to whom you pass
this matter on to I would greatly appreciate it.
I look forward to hearing from you.
Pamela Gardner
844 Fallkirk CT
Coppell, TX 75019
Home: (972)899-0904
Work: (972)444-2127 same as you are currently using.
Mobile: (214) 893-2657