The Weight of Density

If any one single issue has animated the debate over the proposed Lexington Club development (to be built in the core of St. Charles, on the site formerly occupied by Applied Composites), it is the issue of density. Traffic concerns may have actually received a bit more direct attention at the public meetings, but since the impact on traffic in the neighborhood is directly related to the overall density of the proposed development, density is actually at the heart of the opposition to the proposal. The reasons for this opposition are that first, traffic is already troublesome at certain intersections in the surrounding neighborhood at certain times, and second, density is at the heart of what defines the feel of a neighborhood—the residents who are already here do not want the character of their neighborhood significantly changed.

Although one might believe that opposition to the proposed density is irrelevant given the 2007 Comprehensive Plan Amendment’s (CPA) charge about the density of any proposed developments on the site, (“…the current Special Manufacturing land use designation be predominantly changed to the Medium Residential land use designation. In accordance with the definitions in the St. Charles Comprehensive Plan, this designation provides for an overall density of 2.5 to 6.5 dwelling units per acre. The average density in the surrounding residential neighborhoods ranges from 2.7 to 8.0 du/acre, which corresponds well with the proposed Medium Density designation) and a 11/30/11 Staff Report that, on page 4, determined that the density of the proposed development is 6.0 dwelling units per acre (du/ac); it would appear that the proposed Lexington Club development is a perfect fit with the CPA’s mandate.

While the overwhelming gut reaction of the residents in the impacted neighborhood is that the proposed development is far too dense to be a good fit with the neighborhood, the numbers presented to us seem to tell a different story; something was not quite right. When I studied architecture at the University of Illinois, I had a very wise professor who was very fond of quipping that “if you torture the numbers enough, they will confess to anything.” While I am not suggesting that anyone at the City purposely tried to mislead anyone with data provided, I am suggesting that the heart of the widely-shared belief that the development is far too dense to be a good fit for the neighborhood is a fight about numbers. In short, what follows will be this policy wonk’s dissection of the numbers presented, along with a good-faith effort to establish a methodology for being able to more fairly compare apples (the existing neighborhood) to apples (the proposed development).

After much careful study of the data the conclusion I reached is that the gut reactions of the residents are indeed correct; the proposed Lexington Club is 68.8 percent more dense than the surrounding neighborhood. How I arrived at this conclusion is described as follows: the Staff Report of 11/30/11 laid out the calculation for the density of the proposed development. In those calculations, the size of the development is given as 28.7 acres. However, the developer’s own survey drawings give a size of 26.95 acres.  After making this correction, the density immediately rises from 6.0 du/ac to 6.49 du/ac. Next, I looked at the “environmental constraints” figure, where the total gross site size is reduced to take out unusable land, defined as areas of “…ponds, lakes, wetlands, floodplains, slopes greater than 12 percent...” The Staff Report listed the total area of environmental constraints as 5.1 acres. My own calculations (arrived at by doing careful overlay drawings of the 1:100 scale site plan on file with the City, marking and measuring areas that would meet the definition of “environmental constraints”), revealed that there appear to be 5.84 acres of environmental constraints present in the proposed site plan, which means that the adjusted site size falls from 23.6 acres listed in the Staff Report to 21.11 acres. This means that the adjusted site density increases to 6.72 du/ac, putting it just a smidge outside the bounds set for medium density residential.

In an effort to arrive at a true apples-to-apples comparison between the existing neighborhood and the proposed development, I embarked on a survey of the entire neighborhood bounded by Main Street, the railroad tracks, Fourth Street and 12th Street or, as the CPA puts it, the neighborhood “generally to the south of the site.” First, I mapped, at scale, the entire neighborhood using Sidwell maps that are on file at the City. Next, I conducted an informal walking survey of the entire neighborhood, looking to quantify which of the properties were businesses, which of them were residential, and if residential, how many units they each contained. While I cannot absolutely guarantee my residential unit counts, as I do not have access to all the data that the City does, what I can say is that I made a good faith effort to be as accurate as possible, looking at each single family home for evidence of more than one primary entry, electric or gas meter, or mailbox.  I then took the total number of dwelling units on each block and divided that by the gross area of the block, after subtracting out areas that were occupied by business uses, to arrive at a du/ac figure for each block.

What I discovered is that the gut reactions of the residents seem to be exactly in line with the story that the numbers tell: there is a significant difference between the density of the existing neighborhood and the proposed development. The densities of the thirteen blocks I included in the survey (I threw out and , as there is no equivalent land use in the proposed development, and I knew they would artificially lower the numbers for our neighborhood.  I was honestly seeking to compare apples to apples, not to torture the numbers into simply making a confession agreeable to myself), the gross residential densities ranged from a low of 2.97 du/ac to a high of 6.80 du/ac. (The high number is a true outlier, as it is driven by the cluster of five apartment buildings at Dean and 12th; without those five buildings, the density for that block would drop to 2.76 du/ac). The average density for all thirteen blocks is 3.89 du/ac, while the median density of all thirteen blocks is 3.60 du/ac. The gross density of the entire thirteen block study area (the total number of dwelling units on all blocks, divided by the total acreage minus business acreage) was 3.98 du/ac. In comparison, the 6.72 gross du/ac in the proposed development is indeed, quite a bit higher than the 3.98 gross du/ac in the surrounding neighborhood. Specifically, it is 68.8 percent higher.

My conclusion? That the gut reactions of the residents in the surrounding neighborhood are indeed, correct. The proposed Lexington Club development is of a significantly higher density than the surrounding neighborhood and that, as currently designed, it does not fall within the bounds defined by the medium density residential land use designation.