Retractable roofs have become the latest rage in baseball stadium design, and are being built whether they are needed (as they clearly are in Toronto, Phoenix, Milwaukee, and Houston), or not (as is the case in Seattle). BOB’s roof is used to keep the sun off the stands and concrete structure during the 100-degree-plus summer days, and is opened at night to allow air circulation and heat loss to the desert sky.
To enable the grass to survive, the roof is not totally closed during daylight hours, but is operated to create a moving band of sun on the field to permit photosynthesis. This has proven to be a far more workable arrangement than the Astrodome‘s unsuccessful experiment with growing grass indoors.
BOB is located near downtown, and its exterior more closely resembles a very large basketball or hockey arena than it does a contemporary retro-styled ballpark. Taking a cue from minor league parks that feature hot tubs overlooking the game, BOB has a swimming pool in the outfield. There are also 47,000 seats for those fans who are interested in watching the game.
Although BOB has not been a good place for home runs, its 413-foot-deep left-center and right-center corners make it very conducive to triples. Overall, it is neutral with respect to run scoring.