I propose as an urban design principle: No street should carry more than four lanes of private vehicle traffic in a city. No more than two of those lanes should go in the same direction. Most streets should be three, two, or one lane wide.
If a street carries more than three lanes of traffic in one direction, or more than four lanes total, it is not a street, it tends toward being a stroad, in the useful coining of Charles Marohn, and does not belong at surface in the city. It’s existence defeats cross-street pedestrian flows and sucks the vitality from adjacent areas.
Sydney has its share of excellent walking streets, mostly in neighbourhoods. But there are some ‘streets’ that have long, if not always, been too wide, or have widened too much over time. I speak, for instance of Pacific Highway, Gibbons/Regent Street, City Road, and Parramatta Road/Broadway among others (although in the last case, the name “Broad” “Way” gives it away, and word “road” rather than “street” is often an indicator of its early origins and cross-purposes).
Other streets have an appropriate number of lanes, but are just too fast (Hume Highway through Ashfield), as their uses have changed over time, and city streets became designated part of a national intercity highway.
Often the problem is width itself, rather than the number of moving lanes, as a lane is used for parking. Assuming there is desire to retain on-street parking (an assumption which should at least be questioned), there are still solutions. In those cases, curb bump outs and bulbs can be used to tie the two sides of the street closer together for the pedestrian. The parking can be diagonalised rather than parallel in order to reduce the feeling of width.
In a city like Sydney, with its topographically-driven radial street network, traffic tends to be funnelled onto major streets like Pacific Highway with few alternatives. Obviously residents don’t want cut through traffic, so neighbourhood streets have been restricted to local traffic through physical traffic calming as well as regulatory signs. This funnelling exacerbates the problem. While grade separated and pedestrian-free motorways can divert long distance traffic from what should be city streets, induced demand indicate they will always be congested in the peak, and the Downs Thomson paradox states that in peak times cars will move at the speed of grade separated transit (if it were slower, people would take transit, if it were faster, traffic would expand to fill the space allotted).
A more local street, like McEvoy Street carries an excess amount of traffic in the peak on its four lanes, two of which are often for parking or bus stops. This is likely to worsen as WestConnex disgorges thousands of additional vehicles per day onto the newly reconfigured “Alexandria-Moore Park Connector”
Even with only 4 lanes, cars on McEvoy go too fast when they get the opportunity, so much that officials had to put a variable message sign out to remind traffic.
The problem is not just width, it is also signal timings and street right-of-way rules that tame the pedestrian into only crossing with a pedestrian signal.
The city and, since many of these are state roads, the state, need to prioritise movement the kind of travel they say they want: pedestrians, bicyclists, and transit users, over the movement of cars. This begins with street design.