While the misreporting of city population density comparisons commented on by Wendell Cox was probably inadvertent, it is indicative of a general problem relating to contemporary planning – misrepresentation of facts.
We are repeatedly told of the wonderful results of infill high density policies in locations such as Portland, USA or Vancouver, Canada which on investigation are found to be non-existent or applicable only to a small locality instead of to the city as a whole.
Quantitative data is frequently misrepresented. To give one example, a 2008 Canadian study is often quoted as proving high-density reduces greenhouse gas emissions. Inspection and interpretation of the data provided reveals this to be negligible. Without any evidence to the contrary, it seems reasonable to assume that the Canadian fraction of total household emissions that relate to transport is similar to that shown on the Australian Conservation Foundation's website, being 10.5%. Applying this value to the data in Chart 2 of this Canadian study one finds that for those living within 5 km of the city centre there would be a transport difference attributable to increased density of only 1% in total annual emissions per person. For people living 20 km or more from the city centre the difference would be much less at 0.2%.
We are told that high-density imposed on areas originally designed for low density is good for the environment; that it provides greater housing choice, that it reduces housing cost, that it encourages people on to public transport; that it leads to a reduction in motor vehicle use and that it saves on infrastructure costs for government. Not only do none of these claims stand up to scrutiny in any significant way, the contrary mostly prevails.
Movements advocating high-density show characteristics of an ideology, their members’ enthusiasm resulting in a less than objective approach. The desire by these individuals to be socially and environmentally responsible and to identify with a group marketing these imagined benefits is understandable. Some may even benefit professionally. However the result is policies for which no objective favorable justification can be provided and which are not wanted by the greater community who have to live with the consequences.