Mapped: Modal filters

COMMENT & ANALYSIS: The modal filter map was created partly to show that filtered permeability — ie road access arrangements designed to support sustainable transport — is not a new thing in Dublin.

The map was partly in response to an argument that was being put forward that you cannot change motorists’ access to a road or street — this is clearly not the case. It may also help people understand that rat running can be tackled where there is the political will to do so.'s reader-funded journalism won't survive without your help. With over 762,000 views so-far this year, it's not just "avid cyclists" who read this website, but, if you want it to keep going, more support is needed from readers like you. Now, back to the article...

The current Wikipedia entry for modal filter — is an accurate and well-sourced definition of what a modal filter is:

A modal filter, sometimes referred to as a point closure,[1] is a road design that restricts the passage of certain types of vehicle. Modal filtering is often used to help create a low traffic neighbourhood (LTN), where motor traffic is diverted away from residential streets[2][3] and instead toward feeder roads. Modal filters can be used to achieve filtered permeability within a transport network,[4][5][6] and can encourage walking and cycling through more pleasant environments and improved safety.[7]

This map is mainly focused on bollards/planners which closed streets off to through motor traffic while still allowing access and opening streets up to walking, cycling and more livability — the blue points are older measures including bollards and planters, the yellow points are those installed in recent years (including the Phoenix Park trial filters), the orange point is the timed filter in UCD, and the red points are bus gates.

Some of the old filters were on small lanes, others on larger streets that had become rat runs and I’m it’s possible that sure some examples along larger roads might have been put in places as much for traffic flow as for cutting rat-running.

Also included in the map are lines showing some examples of roads and streets which were open to motorists but where restrictions have now been place, ie pedestrian streets, tram-only streets, and roads made one-way for cars to provide two-way cycle paths. These are slightly different ways of filtering some or all traffic out.

The map is partly thanks to readers who submitted suggestions — thank you to those readers!

Any further suggestions?

Do you know of other examples? Are there many examples outside of Dublin of where roads or streets have added filtered permeability?

Because of why the map was drawn up, it focuses on where access was limited via points closures, there’s another sort of filtered permeability where access was designed into areas… but that’s maybe for a different map?

The image below is an illustration only, to get the most of the map click into it.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.