During the first homestand of the season at $1.6 billion New Yankee Stadium, baseballs flew out of the ballpark at an unprecedented rate; the 20 dingers that were clocked during last weekend’s series against the Cleveland Indians were the most ever in a four-game set to open a new stadium in baseball history. Last season, Old Yankee Stadium saw 160 home runs; the current pace would yield a mind-boggling 351 round-trippers for the entire 2009 season. The Yankees did not anticipate that their new ballpark would turn into a Little League bandbox; dimensions at the new park are the same as they were across the street and engineers performed a wind study in advance of construction that did not suggest any major changes in currents or speeds. So, after witnessing several routine fly balls to right field land halfway into the lower deck last Saturday, it struck me that there are some parallels between what’s been happening thus far at the new ballpark in the Bronx and some of the building performance issues that we frequently discuss here at GRELJ.
Specifically, while the new Stadium was projected to more or less play the same as the old one across the street, a number of factors that the Yankees and their design team may not have considered, underestimated, or were outside of their control all along have resulted in a drastically different performance than the club anticipated. For example, the new Stadium stands sixty feet taller and concourses on each level of seating are exposed to the building’s exterior, which may be creating a wind tunnel effect that is blowing baseballs out towards the fences. Interestingly, the Yankees and their engineers are not entirely certain about what will happen to these wind patterns once the old Stadium is razed as demolition has yet to start in earnest.
The analogy here, of course, is where policymakers, owners, or other stakeholders make legislative or project-related choices that are based on projections which do not accurately reflect actual performance once a structure is brought online; these dangers are even more acute where contract documents obligate a project team to achieve a certain level of performance or fixed reduction in operating expenses that are based on a predictive model. The reasons why a building’s performance could diverge may be complex and entirely unanticipated by stakeholders; building science is complicated and buildings themselves are complex systems for which modeling does not always reflect reality. The experience at New Yankee Stadium to date may be a rather simplistic example, but I do think it helps make the point that predicting performance and evaluating performance based on actual data are two very different ballgames.