The WELL Traffic Study Built on Flawed Assumptions

To the Editor:

David Villano’s April 23 article, “The WELL Traffic Study Clears Key Threshold — But Only Barely” discussed an engineering study that examined the incremental traffic that would be expected to be created by The WELL project, a development astride Tigertail Avenue between 27^th Avenue and Mary Street. The study concluded “…the impact of the project on the adjacent street network can be considered de minimis.”  Thus, no modification to the existing traffic pattern was needed (e.g., no need for a left turn lane to enter The WELL to avoid blocking northbound traffic on Tigertail).

In my opinion, the study’s conclusion is based on a fatally flawed analysis. One major flaw, noted in the Spotlight piece, was the assumption about valet parking attendants’ jogging speed. Surprisingly, the Miami-Dade engineer blessed this assumption without asking to understand how sensitive the study’s de minimus conclusion was to it.   

But there is an even more fundamental methodological shortcoming to the study. When I prepared economic studies projecting financial results of a business, we always provided a ranged answer to account for the underlying uncertainty around key input assumptions. Often we relied on what was called a Monte Carlo simulation methodology where key input parameters were varied over a reasonable range. A sensitivity analysis was not done in the traffic study of The WELL. Instead, it relied on one set of input assumptions with no indication of how those assumptions might reasonably vary and affect the overall conclusion. This oversight makes the study’s de minimus conclusion highly suspect.

Another thing to note is that study states that The WELL parking areas will be on two basement levels. A fact that never appears to be included in study’s engineering analysis. (What is also odd, too, is that the study only provides a drawing of one parking level, presumably the senior level, and not the second sub level.)

It is unfortunate that this flawed study was not subjected to more scrutiny before allowing it to be approved. My personal view is that anyone who routinely relies on transiting Tigertail adjacent to The WELL, especially during morning and evening rush hours, is likely to encounter significant delays on a regular basis.

Bill Finan
Coconut Grove