Two-Way Streets Part of a Conceptual Shift
By Ryan McGreal
Published November 24, 2006
Since our latest issue was published to the web yesterday, some vigorous discussions have sprung up on the article and letter dedicated to two-way street conversion.
Part of the conflict between those who support conversion and those who oppose it seems to stem from a conceptual disconnect over how streets work rather than merely a logistical disagreement.
The difference between an urban expressway and a livable street is the difference between a street designed to move people across distances rapidly and a street designed to let people interact more or less in place.
A livable city in this sense is a city in which people do not have to travel far to get where they're going. Rather than making it easier to travel, a livable city brings destinations together so less travelling is required.
Transportation Modes Compared
The preferred modes of a livable city - walking, cycling, and transit - are characterized by:
- Minimal terminal costs - no costs associated with managing your vehicle when you arrive at your destination;
- Minimal energy consumption - the first two are entirely human-powered;
- Planned redundancy - several possible routes from any origin to any destination;
- Compact use of space - walking, cycling, and a full bus have a small 'footprint' on the street, allowing more efficient overall use of space; and
- Optimum effectiveness over short distances - these modes work best when destinations are nearby; e.g. 1/2 km for walking, 5 km for cycling, 10 km for transit.
Contrast the preferred mode of an auto-centric city, which is characterized by:
- Significant terminal costs - you have to park the car somewhere - in offices and stores, parking requirements mean the parking lot has more square footage than the actual building;
- High energy consumption - cars are gas or diesel powered and extremely energy intensive compared to walking, cycling, or transit;
- 'Brittle' engineering - hierarchial design with few possible routes and potential bottlenecks;
- Expansive use of space - cars take up much of the road and encourage more and wider lanes at the expense of sidewalks; and
- Optimum effectiveness over longer distances - this mode works best when travelling to a distant destination; e.g. a 60 km commute to work.
In an auto-centric city, destinations do not have to be close together. Zoning encourages the strict separation of destinations: houses, stores, offices, and factories are all sorted into different zones, and a car is necessary to get from one zone to another.
Breaking the Vicious Cycle
Today, Hamilton is a zoned city stuck in a self-reinforcing cycle of car ownership. The separation of uses requires universal car ownership; universal car ownership requires streets to function as expressways; expressways destroy street life and relegate homes, offices, and stores to specially-designed zones; and we are back where we started.
Changing from a city of zones to a city of neighbourhoods will not happen overnight in any case, but it will never happen until the vicious cycle of car ownership cum expressways cum macro destinations is broken.
The best way to start breaking the cycle is to stop making it as easy as possible to drive everywhere, and simultaneously start making it easier to walk, cycle, or take transit.
People respond to incentives, and today all the incentives encourage people to go on driving. The following changes will shift the incentives away from driving:
- Two-way conversion will make it slower to drive.
- Eliminating "free" parking will make it slower to drive.
- Freeing up the grid by maintaining simple two-way design without over-engineering (no-left-turns, etc.) will make it slower to drive without creating artificial bottlenecks.
- All this slowing of traffic will make it easier to walk or cycle.
- Throwing out zoning laws that separate uses will make it easier to walk or cycle.
- Putting mixed use buildings in currently vacant lots will make it easier to walk or cycle.
- Adding bike lanes (where appropriate) and dedicated transit lanes will make it easier to cycle or take transit.
- Adding a BRT or, preferably, an LRT will make it easier for people to take transit.
- All this will encourage more infill development and reinvestment, which will further reduce the need to travel far to destinations.
Again, this isn't just logistics. It's a conceptual shift away from a transportation system designed to move people long distances from one macro location (a single-use zone) to another, and toward a transportation system designed to optimize density, diversity, proximity, and short-distance modes.
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