Archive for 2014

50,000 new dwellings along Parramatta Road

Written December 8th, 2014 by

New Parramatta Rd Urban RenewalThe NSW Government has released the Draft Parramatta Road Urban Renewal Strategy. The Government is aiming for 50,000 new dwellings and 50,000 jobs in the Parramatta Road corridor by 2050. With eight suburbs/precincts targeted for development and jobs growth.

I am always a bit sceptical about claims made by government when comes to population and employment projections. The high level assumptions these claims are based on tend to be very optimistic.  When you start to apply them on the ground there are constraints (such as easements, property frontages and network infrastructure capacity) that apply at a property level and restrict what growth will be achieved. Read the rest of this entry »

Why flatten the cadastre

Written November 16th, 2014 by

Flatten the cadastreOne of the things you need to determine for an urban growth model is how much more development capacity is available on a property.  In some situations this can be easy to find. For example a property with a single detached house that can be demolished and replaced with multiple attached dwelling units.   The challenge comes when a property consists of common property with multiple attached dwellings or commercial units.

If you treat dwellings/units as individual properties when they are part of a larger building complex or site, there is every chance the attributes of these individual properties would not meet development density criteria that apply to that site. Thus, the model would determine no further development growth could occur at that site. In many instances these sites have further development potential.  Some examples include: an old block of units that can be demolished and replaced with a high-rise unit complex; a site that is being developed in stages over several years and is only part way through delivery of those stages.  Read the rest of this entry »

China builds more houses in 12 years than there are in all of the U.K.

Written October 7th, 2014 by

chinese megacitiesThe growth rates in this article published by New Republic on Chinese megacities seem quite unbelievable: In 12 Years, China Built More Houses Than There Are In All of the U.K. Take the example of Shenzhen growing to 12 million people in 30 years from a cluster of small fishing villages. This gives a compound growth rate of 20% per year, assuming a starting base of 50,000 people.

To put this into perspective, the urban growth models we are dealing with have a compound growth rate around 2% per year.  To service that low growth rate requires investment of many hundred millions of dollars in network infrastructure projects. To have a growth rate 10 times our rate requires investments into the billions of dollars and that is just for one megacity. The article suggests there are at least 6 megacities and 160 cities with populations of more than a million. That is a staggering amount of infrastructure investment required to service that population growth. Read the rest of this entry »

Weather and urban growth modelling

Written September 2nd, 2014 by

Gavin Schmidt presenting at TEDI came across this TED talk by Gavin Schmidt. He is a NASA climate expert and his presentation was about weather models and climate models. In his talk, Gavin explains why we can be confident about predicting how the climate will react into the long-term future.

He discusses the enormous complexities of modelling climate patterns that span a range of 14 orders of magnitude across both time and space. I though modelling urban growth was complex! We are only dealing with 2 orders of magnitude. Even at that level, there is a large body of work required to build and test an urban growth model. I certainly appreciate the mammoth effort needed to build climate models at those scales of magnitude and complexity. Read the rest of this entry »

How to establish a baseline

Written July 7th, 2014 by

Baseline image

The baseline is the most important element of an urban growth model.  Actually, this statement applies to any model. The baseline establishes the reference point from which a model will forecast future growth.  Not having an accurate baseline will result in your model either over or under allocating urban growth, especially in the early projection year cohorts.

Normally your baseline can be derived from the existing land uses of cadastral land parcels within the area that is subject to the urban growth model.  You might think establishing a baseline for a large cadastral model is a very challenging task.  Actually with today’s digital geospatial tools it is relatively easy. Although it is still time-consuming.

So how do you go about creating a baseline? Read the rest of this entry »

Welcome

Written June 3rd, 2014 by

Welcome to the Sizztech blog.

Having developed the Forecaz Modeller and helped our customers use this tool to develop urban growth models, we have discovered there are very few Internet sites out there that aggregate and consolidate information on this topic.

The aim of this blog is to provide a forum where information on generating and maintaining urban growth models can be found. A very “dry” and technical subject we know. For the few of us who have this passion of developing complex models, we hope this blog and the experiences we share here will make your job just that bit easier and over time you might share or comment as well.

We will be periodically writing articles on developing and maintaining urban growth models.  We will try to make these articles generic, for those of you do not use Forecaz Modeller. Hopefully in the future you will check out our urban growth modelling tool. Sizztech is happy to give a demonstration of the modelling tool at your premises or remotely.

We will also source articles relevant to urban growth modelling and include those articles on our blog. Sometimes we will be including articles just because we find the interesting and we hope you will as well.