ROADS Services Training Group
LOCAL AUTHORITY ROADS CONFERENCE 2014
Reforms, Challenges and Safety
Treacys West County Hotel, Ennis, May 2014.
1
Reforms, Challenges and Safety
Design Manual for Urban
Roads and Streets
Sean McGrath
Senior Executive Engineer
Fingal County Council
Lots of Manuals
DMRB
 Traffic Management Guidelines
 National Cycle Manual
 NDA Universal Design Guide
 UK Manual for Streets
 Essex Design Guide

Why Another Manual?
Balance the competing demands of the
“Place Function” as well as the “Transport
Function” of urban roads and streets
 “Place Function” means meeting, greeting,
playing, relaxing, shopping, eating,
community events, tourism, enjoying life!

Place Function
Place and Transport Functions
FUNCTION
Place High
Transport
Low
High
Main Streets
(O’Connell Street)
Bypasses, Relief
Roads
Low
Residential areas,
Shopping streets
Back streets
Speed and Design
• TRL (UK) reports
322, 325 and 551
• Driver speed
based on visual,
psychological
interpretation of
the street.
• Legislation and
regulation play a
secondary role.
Design and Low Speed
Place and Transport Functions
Historically, towns develop
where transport routes cross
 Balance competing demands
 Irish context
 DTTS, DoECLG appointed



a project team
a steering group
Scope and Force
Urban areas with speed limit 60kph or less
 DTTS circular RW 6 2013 (28 March 2013)
 DoECLG circular PL17/2013 (21 Oct 2013)
 Mandatory for all Local Authorities




Forward Planning
Development Control
Own Works
DMURS – Practical Implications

Street Networks




(3.3.1)
Filtered permeability
Orthogonal (Fig 3.8)
Curvilinear
Organic
text
Use a single clear
image or graphic
that illustrates
your point
 Keep your points
short and succinct
 Use bold for
emphasis

Dept. Name
Dublin in Comparison to Similar Cities
Difference is mainly walking and cycling, not public transport
100%
90%
80%
70%
60%
P ubl i c T r ans por t
50%
Wal k / Cy c l e
V ehi c l e
40%
30%
20%
10%
0%
Dubl i n (1. 2
A ms t er dam
M uni c h (1. 3
V i enna (1. 6
Copenhagen
M adr i d (3. 2
mi l l i on)
(0. 8 mi l l i on)
mi l l i on)
mi l l i on)
(1. 9 mi l l i on)
mi l l i on)
Cork in Comparison to Similar Cities
Difference is mainly walking and cycling, not public transport
100%
90%
80%
70%
60%
P ubl i c T r ans por t
50%
Wal k / Cy c l e
V ehi c l e
40%
30%
20%
10%
0%
Cor k (0. 2
mi l l i on)
Fr ei bur g
Odens e (0. 19
San
Gr az (0. 26
(0. 22
mi l l i on)
Sebas t i an
mi l l i on)
mi l l i on)
(0. 18
mi l l i on)
Gr oni ngen
M al mo (0. 3
(0. 18
mi l l i on)
mi l l i on)
DMURS – Practical Implications

Traffic Congestion



(3.4.2)
No new roads – cost, environmental reasons
Maximise efficient use of road space (Fig 3.25)
Accept some level of congestion
DMURS – Practical Implications

Relief Roads




High capacity, but not necessarily high speed
Longer distance traffic, especially HGVs
Take traffic away from urban centres
Inner Relief Road (Fig 3.31)



(3.4.4)
Maintain sense of place
Minimise severance
Outer Relief Road


(Fig 3.32)
Separate from urban area
Strategically planned (SDZ, Local Area Plan)
DMURS – Practical Implications
Signing and Lining (4.2.4)
 Traffic Signs Manual



Advises against over-provision of signs (1.1.10)
“shall or must”, “should” and “may” (1.1.12)
Minimise signage, esp. on local streets
 Better to have self-regulating design

Local Transport Note 2/09
“There is no conclusive evidence that
the inclusion of PGR at any type of
pedestrian crossing or junction has
any statistically significant effect on
safety”
DMURS – Practical Implications
Materials and Finishes (4.2.6)
 Define space, calm traffic, and improve
legibility
 Reduce the need for barriers, signing and
lining
 Need not be expensive

DMURS – Practical Implications
Planting (4.2.7)
 Provide softer landscape


especially in suburbs, neighbourhoods
Consider size and types of trees
 Coordinate with SUDs

(Fig 4.28)
DMURS – Practical Implications
Pedestrians and cyclists (4.3)
 Footway widths 1.8m – 4.0m
 Pedestrian crossings (4.3.2)






(Fig 4.34)
Zebras for moderate flows (Fig 4.37)
Informal (raised?) ‘courtesy’ (Fig 4.38)
Avoid staggered crossings
Minimise crossing distances
Provide refuges (with PBUs at signals)
DMURS – Practical Implications

Corner Radii



(4.3.3)
Reduce pedestrian crossing distances
Reduce vehicle speeds (Fig 4.42)
Allow large vehicles to cross centrelines
DMURS – Practical Implications
Pedestrianised and shared surfaces
 Full pedestrianisation (Figs 4.46)




High activity through day and evening
Retail, commercial and cultural centres
Shared surfaces




(4.3.4)
(Figs 4.46, 4.47)
Transport function is low (eg homezones)
Careful use of materials
No kerbs(?)
Minimise carriageway width and entry radii
DMURS – Practical Implications
Carriageway widths (4.4.1)
 Arterial and link streets lane widths


min: 3.0m, standard: 3.25m, max: 3.5m
Local streets 5.0m - 5.5m carriageway
 Local shared street 4.8m carriageway
 Boulevard (Fig 4.55)

DMURS – Practical Implications
Junction Design (4.4.3)
 Balanced approach – not just car capacity




Reduce kerb radii
Omit left turn slips
(Fig 2.8)
Signals



Ped crossings on all arms
Include ped, bike, bus delays in optimisation
Minimise cycle times
DMURS – Practical Implications
Junction Design
 Roundabouts


Large roundabouts not appropriate




(cont’d)
Difficult for pedestrians and bikes
Limited capacity
Land take
Consider compact/continental roundabouts
DMURS – Practical Implications
Visibility distances (4.4.4)
 Much lower than DMRB (Table 4.2)
 Reaction time 1.5 seconds, not 2 seconds
 Deceleration rate 0.45g, not 0.25g

Alignment (4.4.6)
 Arterial and Link Streets: retain directness
 Local Streets: speed reducing curves (Fig 4.65)

DMURS – Practical Implications
Sight Stopping Distances (metres)
Design
Speed
DMRB
DMURS
30
40
50
60
-
50
70
90
23
33
45
59
DMURS – Practical Implications
Horizontal and Vertical Defections (4.4.7)
 To slow traffic without undue discomfort
 Horizontal (chicanes, pinch points)




Off-set junctions (Local Streets)
On-street car parking
Vertical (ramps, tables)



Long straights (>70m between junctions)
Pedestrian crossings
Entry treatments
DMURS – Practical Implications
On-street parking and loading
 Functions




Calm traffic
Commercial viability of centres
Reduce parking on footpaths
(4.4.9)
DMURS – Practical Implications

What Networks will look like






Permeable neighbourhoods
More pedestrian crossings
No more distributor roads with high walls
Inner Relief Roads - retain place function
Outer Relief Roads - outside urban area
Some level of car congestion
DMURS – Practical Implications

What Streets will look like








Narrower carriageways, wider footpaths
Tighter radii
Shorter cycle times at traffic signals
No left turn slip roads at junctions
No large roundabouts
No pedestrian guardrails
Less signing and lining
More on-street parking
DMURS – Practical Implications

A better balance between the “place
function” and the “transport function” of
urban roads and streets