Brookhaven, GA, August 27, 2015 – A Viewpoint by Jack Honderd – What is “mixed-use development” and why is everyone talking about it? Don’t most towns, by their nature, already have a mixture of uses? What’s newsworthy?
At its most elemental, “mixed-use development” is the use of a building or set of buildings for more than one purpose. It adds up to much more than that though, as we shall see.
A Short History
“Mixed-use development” is often used interchangeably with “smart growth” and “compact development” and the concept is as old as towns themselves. It arose out of necessity, long before the train or car, when town residents needed to be able to walk to work, to the store, to church, to school and anywhere else they wanted to go. Everything needed to be within walking distance.
This began to be seen as a disadvantage in the 1800’s with the rise of industrialization and crowding of workers into cities. Sooty smokestacks, clattering machinery, and chaotic streets drove many residents to long for peace and quiet; mud, garbage and open sewers added to the malaise and sense of poor health. When street cars and public transit became available in the late 1800’s, residents who could fled to the greener outskirts of town, away from the smoke, noise and smell.
The arrival of the automobile allowed a stampede of city residents to relocate to newly-minted suburbs, pursuing fresh air and elbow room, and leaving central cities in danger of collapse. Government and institutional jobs became the mainstay of the central city, and workers happily drove into the city for work and drove back to their suburban homes after 5 PM, resulting increasingly in a deserted city center for 16 hours of each day.
During this process—in the early 1900’s, to be exact—we came up with the idea of Euclidean zoning to protect people’s health, safety and welfare. It’s called “Euclidean” because of the defining Supreme Court case, Euclid vs. Ambler, that established its constitutional basis. “Euclidean” seems appropriate for another reason—the resulting zoning maps divided our towns and cities up into discreet geometric shapes, each conforming to a separate land use, in an eﬀort to protect the denizens of each district from the perceived harm or incompatibility of denizens and uses of adjoining districts. Industrial, retail, oﬃce, residential, and institutional all became sorted into zones dedicated to the propagation and protection of the named activity. Carrying the concept further, residential zones became further divvied up into big, medium, and little single-family, duplex, multi-family, high-density, and more.
Cars became the great connector between the separated zones. Thus, cars became indispensable for grocery shopping, getting to work and school, attending church, visiting friends and virtually every other social human activity. And the omnipresence and aﬀordability of cars encouraged the Euclidean zones to spread out and propagate.
In the last 20 years, we’ve begun to realize the limits of car-generated development patterns and the sprawl that results. We can create only so much road space for a driver in a 70 SF machine, and when a multitude of drivers/machines clump together, we have traﬃc congestion that we begin to find intolerable. In addition, we’re becoming aware of the environmental deterioration—poor air quality, water pollution, climate change—our development patterns and ubiquitous cars foster.
Thus, we have re-discovered the benefits of the historical city. If the grocery store, school, church and work are within walking distance of one’s home, one has a choice to keep the car in the garage. This is the genesis of today’s mixed-use philosophy.
Benefits of Modern Mixed-Use
Research shows that residents of mixed-use developments replace automobile trips with walking trips at least 8% of the time, and reduce VMT (Vehicle Miles Traveled—ie. car use) by 15-50% due to “internal capture” (See thesis here). Internal capture means the car driver’s destination is within the mixed-use development. If a mass transit station or significant oﬃce component is included in the development, car use is reduced even more. The evidence is clear that compact, mixed-use development reduces congestion and air pollution when compared to conventional development patterns.
There’s much more, however.
Compact, mixed-use development:
- increases personal safety and decreases crime. This is primarily a function of creating 24 hour communities with both more “eyes on the street” and more sense of identity and recognition among residents *(1)
- increases sense of community. People who live, play and (maybe) work in a locale have more interaction—intentional or incidental—with neighbors and more dedication to their community.
- creates recognizable urban places that other people want to visit. This in turn adds to the economic viability of local businesses.
- improves public health by encouraging residents to walk. Air and water quality are also improved when compared with conventional development due to lower VMT (http://onlinepubs.trb.org/Onlinepubs/sr/sr298.pdf)
- makes accessible development available to more citizens. Elderly and people with limited mobility can live more autonomously without a car when goods and services are within walking distance.
- reduces public infrastructure cost compared to conventional development patterns. “Compact development” means less lineal feet of road, sewer, water and other utilities per square foot of development and per resident served. Mixed-use development is more eﬃcient than conventional development.
- leaves more land available for green space and public space. This is a logical function of compactness.
- increases property and sales tax base of local government compared to conventional development. This is also a function of compactness, land-use eﬃciency, and 24 hour use. (http://www.planetizen.com/node/53922)
Challenges to Mixed-Use
With so many advantages, does compact, mixed-use development face any opposition? Yes, compact mixed-use implies greater density, and that can be controversial for residents of existing neighborhoods. Change is generally discomfiting, and it’s not always easy to see how a new development model will benefit existing residents. The initial calculation can be “new residents = more congestion.” It’s only after new compact, mixed-use development is in place and restaurants, shops and public spaces are in use that the benefits become obvious.
Mixed-use development is also much more diﬃcult to deliver from a development standpoint. It requires more upfront planning and involvement by design professionals because of more complex building design. Often, old- school zoning regulations present major hurdles. Multiple marketing approaches may be needed because of multiple uses. And financing requires extra resourcefulness and flexibility on a developer’s part as established financing channels are set up for familiar, mono-use buildings. The difficulties dissuade many developers from proposing mixed-use projects.
What’s the Mix?
Once the concept of compact, mixed-use design is accepted, consideration moves to the proper mix of the various uses—how much oﬃce, retail, public, and residential space? What’s the proper balance? Urban places are complex ecosystems that do not oﬀer simple formulas or one-size-fits-all rules.
Ecosystems are rich, interdependent systems. What’s the right number of bears in a woods? It depends on the woods—size, location, food sources, tree species, other animal species, topography—and urban systems are just as complex. Moreover, the ecosystem extends beyond the confines of the site being planned to the larger, surrounding urban area. If Buckhead has excess oﬃce space, how much oﬃce space does a Brookhaven mixed-use development need to include?
The question of mix is one with no universal answer, but urbanists point to some helpful guidelines:
- housing is the core element for all mixed-use development if the goal is to reduce car trips (VMT) and create a safe, 24 hour environment
- local retail is beneficial; on the other hand, large national retail attracts lots of shoppers arriving by car and can increase congestion and reduce walkability
- oﬃce, loft and warehouse spaces provide the setting for jobs—and locally- available jobs reduce car trips and increase vibrancy
- the surrounding urban area will guide the balance of uses to be included. Mixed-use, in its nature, connects with the existing urban environment and looks to provide complementary uses.
- the market is the best arbiter. People will pay for what they need, and developers can only build if they have paying customers. To the extent that the market is variable, mixed-use plans should include flexibility of uses to respond to the market over time.
We started with a basic definition of mixed-use development as the use of a building or buildings for more than one purpose. Through this discussion, we can propose a more comprehensive definition of modern mixed-use development, as described by Michael Niemira *(2):
mixed-use development refers to a real estate project with planned integration of some combination of retail, oﬃce, residential, hotel, recreation or other functions. It is pedestrian-oriented and contains elements of a live-work-play environment. It maximizes space usage, has amenities and architectural expression and tends to mitigate traﬃc and sprawl.
In the end, mixed-use development is about embracing the complexity of urban ecology. It is about building communities where people want to live, and can live with a lessened environmental footprint for years to come.
References: 1 – “Reducing Crime by Shaping the Built Environment with Zoning: An Empirical Study of Los Angeles,” with J. Anderson, R. Bluthenthal, and S. Ashwood. University of Pennsylvania Law Review, 161, 699-756, 2013. 2 – Niemira, Michael P., “The Concept and Drivers of Mixed-Use Development: Insights from a Cross-Organizational Membership Survey,” Research Review, Vol. 4 No. 1, 2007