Can MIT People Really Walk on Water by 2030?

My classmate, Professor Patrick Henry Winston ’65, SM ’67, PhD ’70 identifies a potential problem with the new MIT campus plan in his post "Arrogance" reproduced below.  It appears to me that they also crop  my Dad's old police beat, Union Square in Somerville, off the top of the map. Pourquoi?

 The evolving plan for the campus is newly up on a website, MIT 2030: envisioning our future campus. There are many points of interest, particularly the graphic shown on the Process tab.
The circles indicate where you can go by walking away from the Great Dome for 5, 10, or 15 minutes.

Note that all the circles extend into the Charles River. There are several interpretations.