In 2011 Los Angeles County, USA published the “Model streets design manual” (ref. 2206). The document is worth reading in itself. But in terms of the simplification of its standards the website (here) gives an interesting explanation of its purpose:
“Overall, this manual is intended for three groups of users:
Municipalities who lack the resources to undertake a major revision of their manuals and are looking for examples to assist in re-tooling their current manuals. This document may be adopted as written, or customized for any municipality
Municipalities that want to adopt the latest thinking in street design
Designers, planners and engineers who are looking for tools to provide flexibility within their existing street standard”
In other words the website sees the document as a primary document which could be used and modified for local conditions by other organisations in the USA. Indeed it could also be used and adapted by cities in other countries.
Here we have the concept of a primary document – which can be modified for local conditions. This implied combination of a primary document / local document can also be seen in other countries, for example in:
- Australia – the VicRoads Supplement to the Austroads Guide to Road Design (e.g. ref. 1588)
- Canada – British Columbia Supplement to Transportation Association of Canada Geometric Design Guide(ref. 2209)
Maybe this primary / local document approach could be used globally for different parameters used in the geometric design of roads.
1588 – Australia, VicRoads Supplement to the Austroads Guide to Road Design Introduction to VicRoads Supplement 2012
2009 – Canada, British Columbia Supplement to TAC (Transportation Association of Canada)Geometric Design Guide 2007 Edition
2206 – USA “Manual for living streets”, Los Angeles County, 2011