What is a Master Street Plan?
A master street plan is a plat that depicts both current and, most importantly, all future streets within an entire jurisdiction. That is to be taken literally: within a jurisdiction, within an entire town or city, every single street that is ever going to be built is planned for at once. Think of it as a pre-approved subdivision plat; it is a drawing of a city’s desired urban form.
This may sound far fetched, but history provides us with numerous examples of its successful use. One of the most famous and well-documented[^In 2012, the Museum of the City of New York held an exhibit titled "The Greatest Grid" which explored the history of the city’s grid plan. A book of the same name contains numerous, well-written, insightful essays on the significance of the plan and is well worthy of study.] examples of a master street plan is the 1811 map of Manhattan. At that time, a group of Commissioners, seeing substantial growth looming in New York’s future, sought to provide a physical framework for that growth, one that addressed not necessarily the "what" but the "where" of city planning. They didn’t know what was coming, but they created a logical pattern of subdivision to give all the unknowns a place to go. Over the following decade after the street plan was adopted, the streets indicated on Manhattan’s 1811 map were surveyed in the field. Large stone monuments were used to mark the corners of future blocks with the future right-of-ways offset from them. By physically surveying the streets, the plan was taken from paper into reality and could thus be protected from physical infringement (whether unintentional trespass or otherwise). A master street plan is no good unless it is on a plat that defines precisely where the boundary lines are going to be.
In the Commissioners’ report that accompanied the plan, they projected it would be at least "a thousand years" before the plan was physically realized in its entirety.[^Remarks of the Commissioners for Laying out Streets and Roads in the City of New York, Under the Act of April 3, 1807] The actual streets of Manhattan, however, were largely built out over a single century. But consider the amount of change that Manhattan experienced over that time: exponential population growth, political regimes, building technologies, etc. As development occurred, as developers saw individual needs for housing and schools and shops, the streets were simply constructed per the plan, piece by piece. Remarkably, even with Manhattan’s rapid and history-making changes, this adherence to the street plan lasted well into the 20th century culminating in its eventual and substantial completion.
A master street plan is a simple line drawing, showing the boundary lines that indicate private property and public property. As we have seen, all of urban design can be reduced to a delineation between public and private property. A master street plan reflects this clearly and succinctly.
A street indicated on a master street plan appears simply as two parallel lines which are separated by some scaled distance. A series of 60-foot wide rights-of-way may appear identical on a master street plan, but in reality they may take on dramatically different characters: one my be a rutted-out dirt road, while another my be paved with sidewalks and lined with skyscrapers. The boundary lines are indistinguishable in plan view; they are essentially the same street. But streets grow up differently under different circumstances even if they share the same dimensional DNA. Given enough people, enough building, enough time, and the right dimensions, a rutted-out dirt road can grow into an urban thoroughfare.
We provide two analogies here that may help to further emphasize the utility of a master street plan:
A master street plan is like a jigsaw puzzle: When you buy a puzzle it comes in a box, and on the cover of that box is a picture. That picture is your goal. It guides your placement of the pieces. So regardless of how long it takes you, regardless of how many people are involved, eventually you will reach your goal. And a master street plan operates in the exact same way. Regardless of whether it takes ten years, or a hundred years, or a thousand years, whether it takes ten developers or a thousand developers, as long as there is an established reference, the city will reach its desired urban form. Thus, a city without a master street plan is like a puzzle without a picture: there are no references for where the pieces should go. But unlike puzzle pieces, once the components of cities are placed they are incredibly hard to pick up and move if necessary, making master street plans all the more useful.
A master street plan is like a blueprint for a city: In architecture, the construction drawings of a house reveal the locations of where each wall should be built. A builder adheres to the plan, constructing the walls where indicated. The result, after a while, is a house that reflects the original intention, the original plan.
It is a similar exercise for a city: a master street plan shows where each street should be built. Developers adhere to the plan, constructing new streets where indicated. The result, after years or decades, is a city that reflects the original intention, the original plan.
The building of a house is not left to mere chance, nor should a city. The application of a master street plan is the most direct way to achieve a desired urban form and thus ensure that a certain level of walkability, adaptability, efficiency, and economy are built in.
While a house is built at once, that does not mean it cannot change: rooms can be painted various colors, pictures can be hung from the walls, inhabitants can move in and move out, even additions and renovations are an option. It is similar with a city. Even though a physical street plan becomes locked into place, all the life that happens within that framework of streets is allowed to change and adapt as it naturally needs to. Streets are there only to provide structure, not content.
Planning in the Right Order: Subdivision and Zoning
City planning is a complex process, especially in our modern times. However, it can largely be reduced into two primary domains: zoning (the regulation of private property) and subdivision (the order of public property). These two domains compete for attention, but over the last century zoning has come to dominate the process.[^Knack, Ruth and Israel Stollman. “The Real Story Behind the Standard Planning and Zoning Acts of the 1920s,” Land Use Law (February 1996).] We will show here how putting zoning first is detrimental to the more permanent and important patterns of subdivision.
In many jurisdictions around the world today, zoning is the first step in the land development process: residential here, commercial there, and office over there. This is promoted as the most important determinant in advancing health, safety, and welfare and in protecting the public interest because of the power it has in separating incompatible uses. The concept of keeping incompatible uses started off in a logical manner—do not build houses next to a coal-burning factory—but over time the definition has become broadly applied to almost anything (e.g., keeping multi-family units away from single-family units). [^For more on this history, refer to works by Ruth Knack, Michael Wolf, Jane Jacobs, and Andres Duany in the bibliography.]
Only after the land uses have determined is subdivision taken into account, and this is only done on a parcel by parcel basis. What happens in this way, however, is that the subdivision patterns produce a street network that has no additional connectivity because the patterns are bounded by each individual parcel under consideration (i.e., there is no plan present that says leave a street stub out here on your property for a future connection across another property). Zoning, by definition, is a private matter.[^See the first sentence of the first page in A Zoning Primer written in 1926 as a guide to the Standard State Zoning Enabling Act written in 1922.] To limit the planning of streets (which is by definition a public matter) to the confines of private parcels is one of the greatest errors—if not the greatest error—of our modern planning process. As new development occurs, it latches on to the existing street network.
When zoning occurs first and subdivision is determined on a parcel-by-parcel basis, the inevitable result is an unwalkable, unsustainable urban form, one that minimizes connectivity, minimizes street frontage, minimizes opportunities for vitality, minimizes the ease for redevelopment, and minimizes public space. The poster child of this urban form is the cul-de-sac. Cul-de-sacs are great at accommodating quiet, single-family detached houses, but that’s it. By design, they are largely incompatible with other uses. This has been the dominant urban form in post-WWII America. Unfortunately, it coincided with a boom in population, production, and development, ultimately surrounding our cities with first, second, and third ring suburbs. When more development and people occupy a network of this type, that means the density of cars goes up, which worsens traffic problems. The only solution in this context then is to expand the capacity of each individual road by adding lanes, which spurs more development and more cars.[^This concept is known as induced demand. See works by Andres Duany and Jeff Speck in the bibliography.]
But there is an alternative to this approach: putting streets first and land uses second. A master street plan is the first thing to consider in a streets-first process. In this way, as development occurs it is known that the resultant street network has built-in connectivity, built-in walkability, and built-in adaptability, so that in the future when things change (recall from the Introduction that things will change as much as you may not want them to) that change is readily absorbed and accommodated in a proven pattern of urban form. Zoning can adjust as it needs to on top of the street plan. People can move in or move out, buildings can shift around, and the street plan can be the constant background for that development. And it all works because the streets, blocks, and lots are a function of a time-tested dimensional DNA.
The Benefits of a Master Street Plan
There are many benefits to incorporating a master street plan into the planning process, including:
-
Frees up municipal resources: As a pre-approved subdivision plat, a master street plan streamlines the review process. This allows planning authorities to focus on other critical issues, like affordability and housing. Without a master street plan, every development must be reviewed as new, unnecessarily waisting time and soaking up resources. However, if the jurisdiction’s subdivision plan is completed all at once, then as long as a developer conforms to the plan the review time is minimal. If the developer wishes to deviate from the plan, they can do so, but they have to submit a variance.
-
Saves developers and home buyers time and money: As a pre-approved subdivision plat, developers can get their projects completed more quickly and at reduced cost, with the efficiencies and savings trickling down to the home buyers.
-
Prescriptive, not postscriptive: Rather than relying on after-the-fact tactics, once the harm has already been done, or ineffectual connectivity metrics, or parcel-by-parcel subdivision reviews, a master street plan ensures that a desired urban form will materialize.
-
Guides incremental development: While a master street plan is established up front, its execution occurs over decades and centuries. As the city grows, a master street plan is there to guide that growth.
Designing a Master Street Plan
It has been shown that streets provide important functions beyond those of mere transportation purposes and that they are the longest-lasting elements of a city’s infrastructure. Now the question we have before us is how does one design a master street plan? The best way to determine that is to look at precedent, to look at the best examples of town planning the world has to offer. There are many sources one can to turn to to assemble this list of precedent, but for this paper we are focusing on those neighborhoods selected by the American Planning Association as the most walkable, sustainable, and enjoyable.[^Refer to https://www.planning.org/greatplaces/ for more information on the criteria of selection]
The following is a partial list of precedent used for analysis in this paper which includes many of the neighborhoods designated by the APA as "Great Places of America" as well as other cities from around the world to broaden the scope of research: Amsterdam, Aosta, Ashland, Austin, Baltimore, Banff, Bangkok, Barcelona, Beaufort, Beckley City, Boise, Boston, Brunswick, Buenos Aires, Cacalchen, Cairo, Cape Town, Charleston, Cincinnati, Durango, Evanston, Forest Hills, Franklin, Frederick, Grand Rapids, Hattiesburg, Innsbruck, Istanbul, Key West, Kuwait City, Lafayette, Madison, Marfa, Mason City, Miletus, Mones Cazon, Montgomery, Nantucket, New Delhi, New Orleans, New York, Oak Park, Owatonna, Paragonah, Paris, Providence, Riverside, Savannah, Siloam Springs, Spokane, St. Augustine, Staunton, Vienna, and Walla Walla.
Analyzing precedent
These precedents have all the characteristics of great places: they possess some combination of walkability, sustainability, enjoyability, beauty, and vibrancy. By carefully analyzing their urban forms—their streets, lots, and blocks—we can learn what urban forms yield the best urbanism. By measuring block sizes and their geometries, right-of-way widths and their networks, we can determine the ideal structure of the best cities in the world. While the precedents mentioned here represent the spectrum of urbanism—from small towns to large cities, from East to West—they possess uncanny similarities in their mutual urban forms. Our research reveals a universal law of urbanism, a common dimensional DNA, that results in their successes. That universal law is presented below in four major rules: block size, block geometry, right-of-way width, and alleys. These rules can be applied to small developments, entire neighborhoods, or whole cities.