Runoff, Wetlands and "Zone A" Flood Hazard Areas
BLMH is high and dry, but is bounded by "Zone A" Special Hazard Areas to the north and south. These areas will be "inundated by the 1% annual chance flood events." In other words, the water levels of Lakes 3, 4 and the wetlands on COD property will rise during a "100 year" flood. As the levels rise, the water flow from Lake 3 to Lake 4, and from the wetlands to Lake 4, will increase. There is a large underground connection between Lake 3 to Lake 4. However, the flow of storm water into Lake #4 is greater because of the connection from the wetland to the east. That wetland, in turn, receives runoff from the College of DuPage.
This post will be shorter than the previous one.(Note 4). I'll provide sufficient photos to stitch together the story and provide the locations and relationships of some of the structures described.
Here's an overall view of the western extreme of the campus and of most of BLMH, as it existed in the spring of 2012. The view faces North by Northeast and provides an indication of how the special "Zone A" areas and the COD campus "boxes in" the association. Lake #3 is to the North, the college is to the east, Lake #4 is to the South, and the "wetlands" are to the Southeast. This also shows the recent "material staging" and "pond 9" college construction, both of which are incomplete. This post will focus on the southwest area of the campus:
Click on Photos or Graphics to Enlarge Them!
The wetland of concern is in the southwest corner of the campus. That wetland drains into Lake #4. This post will detail how this drainage system is interconnected.
Problems in the wetlands can result in flooding at the church south of the campus and west of Lambert. Since that church is adjacent to the satellite antenna farm of the college, it must be in the area the college recently referred to as the "Service Area" of the campus! Here's the Church, the satellite farm and the Radio Tower of the campus, south of "Parking 6." This is due east of the wetlands, the beginning of which is visible surrounding the radio tower:
Consequences of High Water Levels
High levels in Lake #3 or 4 can result in shoreline damage and an increase in the fees that our owners pay to maintain these shorelines and to deal with the consequences of problems on the lakes. In other words, if the college doesn't get it right, under the current system our owners will pay to clean up the damage.
The lakes and the "wetlands" on COD property are part of a complex, interconnected system to control rainwater and avoid flooding in this part of the County. It does this by providing some "retention" of rainwater and by also providing controlled flow to larger water storage areas to the south of Butterfield Road. Disturbing this system can have grave consequences for the residents of nearby communities. During high rain periods and large rainfalls, the flow to downstream areas is constrained by the capacity of the underground interconnections.
"If the amount of water entering the wetlands isn't properly controlled, a surge into lake #4 can be the result, and that in turn can result in unusually high lake levels..." This is described later in this post. "Unusually high lake levels" is flooding!
This "Zone A" proximity to our association is one of the reasons I am concerned by recent COD construction. This post will focus on some of the construction, may reveal how it has contributed to my concerns, and asks questions. There are constraints for building in or on wetlands, and there are "buffer" requirements according to County codes. There may also be issues under Federal mandates. So how is it possible to build what appears to be an underground pipe from the Pond 9 area into the wetlands? Or, perhaps I don't understand the restraints.Or perhaps the area is a "wetlands" in name only and is not recognized as such.
It appears the college constructed a new retention area and storm sewer to carry runoff from the campus parking areas to the wetlands in the southwest corner of the campus. I became aware of the retention area when our association manager and maintenance company obtained a copy of a drawing of the details of the "Parking Improvement Program" announced by COD. However, there were few details provided of the mechanical or civil engineering aspects of this construction. At the time, the college was in a very serious dispute with the Village of Glen Ellyn, which was essentially about the college being perfectly able to monitor itself and that Village inquiries were meddling in the internal affairs of the college.
However, on review of the information contained in this post, I must ask "Who was aware of the full extent of this construction?" "Who authorized it?" Finally, are all codes, etc, being adhered to? Do you know? Does anyone? In fact, because the college has taken the position it is fully capable of monitoring itself, I suspect no one outside the college is really aware of the full magnitude of this construction.
There was no storm sewer connection or new sewer to the wetlands on the drawings provided to our association in August 2011. When we questioned the college about this construction we were given a plan of the campus showing "parking improvements" bolded. Here's a detail from those plans. Beyond the "Pond 9" do you see any "runoff" control devices or sewers to the wetlands? Neither did we, and we were told this would be a "grassy and bermed" area. That is not what was constructed, and it seems that it included additional runoff control features. We have been told the pond has been revised and will be larger, but will be completed in 2012.
Clicking on Photos or Graphics will Enlarge Them!
A Current Concern - A New Runoff Connection into the Wetlands
In 2011, the College of Dupage announced a "Parking Improvement Program." We discovered that program included a new "Retention Pond" in the southwest corner of the campus, bordering a wetland, BLMH, and Lake #4. You can see it in the drawing above.
In August, 2011, I began monitoring the construction. The construction of the parking lot improvements apparently included a new underground pipe to carry runoff from the parking improvements into the wetlands to the south. This construction was in our lap, and it was possible to view some of it, but not all. When we saw new concrete piping, we wondered "where does that discharge?" Then I used Google Maps, Earth, Bing and Yahoo satellite images. I published some photos on May 9. I noticed what appeared to be a triangular concrete discharge, to carry runoff into the wetlands.
The photos in this post show this construction.
RM-0154 Flood Map
Here's a detail of the area around BLMH from the DuPage County RFM-0154 Flood Map. It includes most of COD, which is on the eastern side of the red line labeled "Glen Ellyn." What Wheaton calls "Lake #3" is to the north of BLMH and Lake #4 is to the south. The blue "Zone A" on the right side of the red line labeled "Glen Ellyn" is the wetlands inside of COD. This map is why I am concerned and vigilant about construction in the southwest corner of the college campus.
COD Construction to the North of the Wetlands:
In 2011, the college began what was labeled a "Parking Improvement Program" in our laps. Drawings provided by the college indicated a "retention pond" which is now called "Pond 9." It was to be grassy and bermed. That did not happen. With the limited information available I've concluded that the construction includes piping which connects the campus and drains runoff into the adjacent wetlands.
Here's the view east into the campus, very early this spring, 2012. The dig includes a new "material staging area" on the left, which was unannounced and probably not on any plans. Certainly not on any that we were provided. This project also included what appears to be a retention pond which is not per the original drawings provided by the college in August-September 2011.
The retention pond seems to include a collection point in the southeast corner, which is connected to the wetlands via an underground concrete sewer. This is clarified in the next few photos:
Here's a close-up of the "retention area." My interest in this was piqued in the fall when I noticed a new concrete and steel inlet grate and manhole cover. These are visible in the 1:00 o'clock position of the retention pond. The question I wondered was "where are these transporting runoff water to?"
Here's a close-up of what appears to be an inlet to convey runoff from COD to the Wetlands to the south. It was taken with a telephoto lens from BLMH. With the construction debris and mud, it's a bit difficult to see, but it is clearly visible from above:
Here's another aerial view, showing apparent construction to a discharge point in the wetlands, which is the "V" shaped white concrete on the right of the photo:
Here's two photos of the same area, but this time, with a view facing north. It shows the entry point of runoff from the COD campus at the top of the photo. The "wetland" lake is at the bottom of the photo. It appears that the discharge point of a new storm sewer pipe is into the wetland "lake." The Lake#4 is off screen to the left. As can be seen, there seems to be a triangular concrete discharge of the new underground pipe to convey runoff from COD's campus into the wetlands!:
Here's a view from Lake #4 facing east. The construction above is in the left corner.This photo is included to show the flow path from COD into the wetlands and from there into Lake #4. The discharge point of the wetlands into Lake #4 is clearly shown in this photo. You can see some of the roofs of homes in BLMH on the lower left of the photo:
Here's a detail of the connection between the wetland lake and Lake #4. It's highlighted with a yellow pointer. This is the location of a concrete "weir" on COD property, which is the flow connection point into Lake #4:
The Connection from CODs Wetlands and Lake #4
Here's a few recent ground level photos of the water connection between the COD wetlands and Lake #4. The next photo shows the view from Lake#4 facing east, in the direction of the yellow arrow in the photo above. COD's wetland and the "flow control weir" are clearly visible. These photos were taken during the current "rain water deficit" in the area, so flow from CODs property to the wetlands and then, via this weir to Lake #4, was low.
The weir will not hold back flow from the wetlands during unusual situations. As the water level in the "wetland" rises, it will simply flow over the weir and inundate the downstream lake #4. One wonders if the construction is sufficient to survive a serious flood incident. So, if the amount of water entering the wetlands isn't properly controlled, a surge into lake #4 can be the result, and that in turn can result in unusually high lake levels, and extensive shoreline damage. :
Here's the view of the flow from COD's wetland into Lake #4. Some of the BLMH buildings are visible on the far shore:
What does the "weir" really look like? Here is a photo of it. Lake #4 is to the right, and as you can see, water from COD flows over the "weir" and into Lake #4. The weir in this photo is entirely on COD property:
Notes:
- This post is my point of view, with the information I have access to. I was provided absolutely no assistance by anyone in preparing this post, or the others relating to "COD Expansion."
- Some of the other residents are busy preparing for the annual "picnic" at BLMH. Ya gotta have your priorities, ya know!
- I am somewhat concerned by what appears to be a storm sewer, constructed by the college, the discharge of which is in the wetlands which in turn discharge into Lake #4
- Links to Part I and Part II of this series: Click for Part I Click for Part II
- The next step will be letters to the county, the city of Wheaton and to our District 42 representative about this. I may attempt to get close up photos, to further corroborate this post.
- I do realize that the lengthy posts may turn readers away. We're all busy, right? In this age of the "30 second sound bite" more than 5 sentence may be too much. But I cannot present this without substantiating it. I also write these as if the reader was not completely familiar with the content. In an association in which we frequently get new owners, this might be boring to the "old timers" but that's not my concern. In an association where owners complain, ask for more information, and then don't bother to read the newsletter, I have to be honest and say that what I present is for those who are interested and motivated. This isn't about entertainment, or popularity. In fact, in our society, people go to great lengths to avoid unpopular issues. So if that's who you are, then this is not for you!