The idea of a Complete Street is compelling in almost every way, but when the engineering profession begins to adopt it wholesale, we need to pause and look at the outcomes. Are we getting Complete Streets, or are we getting Complete Roads. The difference is tremendous and will impact the financial viability of an approach to building places that is long overdue.

The Complete Streets concept is one that is long overdue. We've spent two generations transforming a public realm once comprised of walkable, mixed-use neighborhoods into auto-only zones. These are places where the kids used to play ball in the street. Today a kid can't even play safely in their own front yard.

At Strong Towns, we've worked to illuminate the fact that this transformation has been done at tremendous financial cost. This is not only because the construction of wider, flatter and straighter streets has been expensive, but because the auto-centric nature of the transformed public realm drives private-sector investment out of traditional neighborhoods, dislocating it to places that provide more buffering to the car.

Not only that, but the redevelopment that has happened in these neighborhoods has largely been on a suburban framework, using the parking ratios, setbacks and coverage restrictions of modern zoning to reduce density (and the rate of return). Financially, these places are largely insolvent, lacking the tax base to maintain their basic infrastructure.

Enter the concept of a Complete Street. To me, the fundamental contribution of Complete Streets to the discourse surrounding the future of our towns and neighborhoods is the recognition that our streets must serve more than just cars and that the public realm can no longer be an auto-only zone. The fact that the Complete Streets model has broken the stranglehold that the auto-only design mentality has had on our streets should be the cause of unending rejoice.

In March I was able to have dinner with Kaid Benfield. During the course of our conversation, he enlightened me on how the Leadership in Energy and Environmental Design (LEED) standards were tweaked with Neighborhood Design principles. The result, LEED-ND, takes a great concept -- buildings that are energy efficient and environmentally friendly -- and overlays it on a development framework that reinforces these principles. In other words, no more "green" buildings in the middle of a greenfield, with 30 mile commutes each way.

In a similar vein, we're going to now, humbly, suggest a way in which the Complete Streets concept can evolve to achieve what I believe is its principle intent, that being Complete Neighborhoods. 

I've now seen two projects where engineers promoted the use of "complete streets". In each I see the engineering profession co-opting the Complete Streets moniker without any thought to a Complete Neighborhood. For the engineers on these projects, the approach remains the same. I'll quote from our piece, Confessions of a Recovering Engineer:

An engineer designing a street or road prioritizes the world in this way, no matter how they are instructed: 

  1. Traffic speed
  2. Traffic volume
  3. Safety
  4. Cost

The rest of the world generally would prioritize things differently, as follows: 

  1. Safety
  2. Cost
  3. Traffic volume
  4. Traffic speed

In other words, the engineer first assumes that all traffic must travel at speed. Given that speed, all roads and streets are then designed to handle a projected volume. Once those parameters are set, only then does an engineer look at mitigating for safety and, finally, how to reduce the overall cost (which at that point is nearly always ridiculously expensive).

One of the places I've seen Complete Streets applied is My Hometown's Last Great Old Economy Project (also known as the College Drive project). In this instance, the design starts with a minimum design speed and a projected traffic volume, the latter being the stated impetus for the project. This analysis provides us with four lanes of fast-moving traffic. The engineers then move on to the "safety" criteria and the mandate that -- if we can afford it -- we accommodate bikes and pedestrians. This is done, of course, at tremendous cost - estimated at over $7 million for a mile of road.

Now notice that I called this route a "road" and not a "street". Understanding the difference between a road and a street is critical to understanding the problem we have with engineers misusing the Complete Streets approach. From our Placemaking Principles for a Strong Town:

To build an affordable transportation system, a Strong Town utilizes roads to move traffic safely at high speeds outside of neighborhoods and urban areas. Within neighborhoods and urban areas, a Strong Town uses complex streets to equally accommodate the full range of transportation options available to residents.

Roads move cars at high speeds. Streets move cars at very slow speeds. We should build roads outside of neighborhoods, connecting communities across distances. We should build streets within neighborhoods where there are homes, businesses and other destinations. The auto-road is a post-WW II replacement of the rail-road. The street should be what it has always been; the street.

The fundamental design flaw of the post WW II development pattern -- the false premise upon which every other design tragedy has been committed -- is the transformation of our streets into roads.

High speed auto travel has no place in urban areas where the cost of development demands a complex neighborhood pattern with a mixing of uses, multiple modes of travel and a public realm that enhances the value of the adjacent properties. High speed traffic destroys value in our neighborhoods. It drives out investment. There is no amount of pedestrian enhancement that we can build to offset the negative response people have to being in the close proximity of speeding traffic.

Without aggressive traffic calming -- which is part of the Complete Streets playbook -- we will simply be building Complete Roads. A Complete Road will not transform the public realm, no matter how much money we put into accommodating pedestrians and bikers with bridges and tunnels. A Complete Road will not attract significant private-sector investment in the key neighborhoods where we have so much existing infrastructure liability. And a Complete Road will cost a fortune, without changing the insolvency problem facing our cities.

If there is one thing our current financial situation should teach us about the engineering profession it is this: engineers will bankrupt us if given the chance to build our cities and towns the way they envision them. It is predictable that the engineering profession will embrace the concept of a Complete Road -- which is nothing more than a bad design made PC by throwing an expensive bone to bikers and pedestrians -- because it fits with their hierarchy of values (speed, volume, safety and then cost). Insidiously, promoting Complete Roads will ensure them more funding than they would otherwise receive. You can call them "streets" all you want - unchecked, they are going to build "roads". (For example, check out the 14-foot highway lane widths on the Complete "Street" cross section on My Hometown's Last Great Old Economy Project).

We love Complete Streets. They are essential to a Strong Town. Let's get out there and build them, but make sure the engineers don't con you into a Complete Road. Demand slow cars and a Complete Neighborhood to go along with your Complete Street.

Additional Reading:

(Top photo source: Andre Carrotflower)

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