SLEEK EXPENSIVE apartment houses with river views. Laboratory and office buildings in symmetrical rows. A hotel, a conference center, a central plaza. Upscale retail at ground level. Trees, planters, native plants. An enclave of  privilege. Such is Harvard’s vision so far for its new Enterprise Research Campus in Allston.

Alternatively, consider this: a dense aggregation of three-deckers and duplexes, an assortment of young adults, immigrants from all over, older multigenerational families, musicians, artists, service workers, a rich mix of incomes, ethnicities, points of view. Such is Allston as it is today. If a city is defined as a place where the unexpected can happen at any moment, then Allston is the quintessential city district.

Which of these development patterns would produce a more vital and resilient community? Harvard’s research campus would design a homogeneous and predictable space largely inhabited by members of one income bracket, one class, a productive and prosperous city district but a sterile one. Its development partners and its investors prefer this predictable, lucrative, monochromatic version of the new Allston in place of the old one. They would give us a replica of the Seaport District, where invisible walls have effectively excluded the diversity that characterizes the unpredictable city. But at what cost?

With surprising speed, much of North Allston—not just the Enterprise Research Campus—is being transformed from the second sort of city to the first. A brave new world is taking shape, here and elsewhere, a world of lab spaces to employ an army of highly educated and well paid scientists and technicians. A world of expensive apartments and condominiums, too small for families, too expensive for the ordinary working people whose service labors will make this world possible.

What we witness taking shape along Western Avenue is the market economy drawn out in three dimensions. Money follows money and builds its new city districts to house that new economy. People take their places wherever they can in this monetized space. People with incomes below the median will have to look elsewhere for a place to live, and commute if they can to a job in the new economy.

What is driving this exclusive pattern of development Harvard and its developers are proposing for the Enterprise Research Campus? Above all it is the prevalence of exorbitant market rents that lead to a residential community consisting mainly of households with double or triple the median income. Our economy increasingly divides the once mighty middle class into haves and have nots, winners and losers. Harvard’s research campus would be an enclave of winners. In a truly equitable community, half of the households would live on income below the median. Mixed income is a hollow description if 80 percent of this “mix” earns several multiples more than the other 10 or 20 percent. Allston today is a truly mixed income community.The Enterprise Research Campus threatens to erase that distinction.

A thriving urban district needs more than truly affordable housing. At a time of climate crisis and environmental degradation, this large swath of new urban fabric should be built around green spaces that promote resilience, health, and natural beauty. In its first stages, Harvard’s developers include substantial “open space,” much of it paved and privately owned. A better plan would be to map out a network of truly green public spaces–think Emerald Necklace–and arrange the construction around that master plan, a green plan for our greening century.

Similarly a new urban district in deeply congested Allston will only thrive with granular, comprehensive transportation planning. Not the admirable pedestrian, bike, and shuttle systems already proposed, and not the hope of a commuter rail station, but a greatly enhanced public transit service connected to the regional grid. While such a plan exceeds the capacity of most developers, Harvard is the exception–a titan that justly evokes the highest expectations.

As we residents of the existing Allston contemplate the future district rising right next to our neighborhood, we see the possibility of an equitable, inclusive, inspirational new urban district. We see it in our minds but not yet in the plans Harvard has filed. We are eagerly waiting for this great institution to propose and build urban fabric worthy of its greatness.

Brent Whelan is a resident of Allston who has been a member of the Harvard Allston Task Force since 2006.