In her seminal book The Death and Life of Great American Cities, city-builder Jane Jacobs noted that “a Central Business District that lives up to its name and is truly described by it, is a dud.”

Jacobs’ call was for the centre of a city to have a mixture of uses that were more than the traditional focus on jobs. She called for a diversity that made cities bustling people places 24/7. Two recent planning policy changes to the CBDs of Sydney City and Parramatta may have the effect of making both of these centres a dud in Jacobs’ definition.

University of Sydney student Caitlin Hanrahan, who won a Bradfield Scholarship last year, proposed a change to the term CBD as she agreed with Jacobs that the mono use of only business was not what a dynamic city needed. Hanrahan called for the new term of CLD, Central Living Districts, so that all the aspects of a bustling central city precinct could be acknowledged. Planners traditionally liked to divide cities up into separate uses but Hanrahan believed planners now need to promote a mixture of uses.

The Sydney City Council has recently issued a Central Sydney Strategy that aims to slow down residential construction in the city centre in favour of more jobs. This is a reversal of the policies of previous Lord Mayors who championed ‘Living City’ policies to encourage the diversity and vitality Jane Jacobs called for. The slowdown is not a prohibition, as residential is allowed in small buildings or in taller buildings as long as half the building is for commercial uses. The development industry, however, is concerned that the 50/50 mix will be hard to make work and that the changed rules could lead to very little new residential development in the city.

While it is admirable to promote more jobs in city centres, the reality is that this is happening anyway with activity-based working, where hot desking and open plan layouts have dramatically increased the number of people per floor. So more efficient office layouts are helping the provision of more space for jobs. Clearly, the area required per person for residential space however is far greater than that required for office space, so residential will always need more buildings. The previous policies that have encouraged more residential accommodation in Sydney’s centre now appear to be seen by planners as being too successful.

Jacobs has a whole chapter on “The self-destruction of Diversity” where she explains that outstanding success in promoting a particular use can cause it to collapse upon itself. The Living City campaign in Sydney has been so successful, according to the City of Sydney, that it needs to be slowed down, but the new planning rules could destroy the diversity of the living city.

While planning changes to Central Sydney could minimise new residential buildings a similar swing against residential buildings seems to be happening in Parramatta. The NSW Government has announced that it wants Parramatta to be the ‘dual CBD’ along with Sydney city. This is a promotion from being the second CBD and is an important acknowledgement of the growing importance of Western Sydney.

Parramatta has been booming with many tall towers being proposed and under construction, but nearly all of these are residential towers on sites that ring a relatively untouched commercial core. The commercial core probably needs to be relaxed to encourage mixed use development where residential can support a component of commercial space in a new building. The Greater Sydney Commission has recently changed the overshadowing rules for Parramatta’s centre and two residential towers look like they will be stopped. This change in the rules is likely to slow down growth in residential towers, but it is unlikely that new commercial buildings will replace them.

Parramatta needs the diversity and lifestyle that Jacobs has called for and that means more people living in the centre. With a cosmopolitan character to the city centre, it is likely that jobs will follow. Clearly, it is the private sector that needs to invest in both Parramatta and Sydney city centres but recent changes to planning rules in both centres could have the effect of slowing down the current swing to urban living with the hope that a swing to more jobs will follow.

Planners need to heed Jacobs’ advice of 50 years ago and that of Harrahan in 2015 and drop the B from the term CBD. Our city centres must have diverse uses that make them attractive for everyone and they probably need to be simply called city centres or CLDs. As Jacobs has correctly, identified a centre that is only about business will become ‘a dud.’

The recent planning policies for Parramatta and Central Sydney seem to be turning the clock back to the city centre as being for work only. While the changes are likely to be gradual, it is the message to the private sector that residential is being restricted in the two centres that could lead to a less diverse character. These policy settings need to be carefully managed as our city centres grow.