Tools for Representing and Appraising the Distributional

Impacts of Policies

Example: Streetspace Allocation

Peter Jones & James Paskins

Centre for Transport Studies, UCL

Leeds, 21st May 2007

Current Situation• Authorities encouraged to measure distributional

impacts of strategies and schemes – but little guidance

• Main advice relates to taking into account effects of income differences (e.g. equivalence scales, distributional weights)

• Recent legislation in UK to ensure no discrimination, in terms of disability, age, ethnicity, gender – strengthens case for examining distributional impacts

Distributional Dimensions

• WHO: Social group distribution (‘vertical equity’):– Directly affected (e.g. children)– Indirectly affected (e.g. parents)

• WHERE: Spatial distribution (‘horizontal equity’):– Design area– Wider impact area

• WHEN: Temporal distribution:– Time period– Generational/cohort differences

Requirements of Tools

• Aid identification of relevant social groups, plus spatial and temporal impact areas

• Identify relevant categories and measures of impacts

• Provide basis for assessing gainers and losers, and severity/significance of change

• Consider possibility of integration into current appraisal methodologies

Types of Tool Development

1. Congestion charging: Bristol, Edinburgh (PROGRESS), WebTag guidance

2. Accessibility Planning: Barnsley Dearne, South Yorkshire

3. Streetspace reallocation: Bloxwich, West Midlands

Streetspace Reallocation

• Increasing emphasis on redesigning high streets:– Encourage more sustainable modes– Regenerate high streets & increase liveability

• Given space/capacity limitations, more for one group often means less for others

• Need a method of assessing design needs and gainers/losers under different options

Option Generation & Appraisal

Winners and Losers Net Benefits

Determine Street Type

Determine Street User Groups and Activities

Determine Required Street Elements

Determine Desired Numbers/Space

Determine Net Nos./ Space Requirements

Appraise Against Current Conditions

Generate Streetspace Design Options:

•Types/Numbers Street Design Elements• Location of Street Design Elements

Winners and Losers Net Benefits

Determine Street Type

Determine Street User Groups and Activities

Determine Required Street Elements

Determine Desired Numbers/Space

Determine Net Nos./ Space Requirements

Appraise Against Current Conditions

Generate Streetspace Design Options:

•Types/Numbers Street Design Elements• Location of Street Design Elements

Determine Street Type

Source:‘Link and Place - A Guide to Street Planning and Design’

I-B I-C I-D I-EI-A

II-A

III-A

II-B II-C

III-B

II-D II-E

III-C III-D III-E

V-A

IV-B IV-C IV-D IV-E

V-B V-C V-D V-EL

oca

l

Ne

igh

bo

ur

ho

od

Dis

tric

t

City

Na

tion

al

Neighbourhood

Local

District

City

National

IV-A

Arterial streets

Non-arterial streets

Place status (A, B, C, D and E)

Lin

k s

tatu

s (

I, I

I, I

II,

IV a

nd

V)

Link/Place classification matrix

Select Street User Groups/Activities

Street type

User group … I - E … III - B

Retail … V - E

Pedestrians Pedestrians who have mobility difficulties Those using the street to socialise/relax Cyclists Bus users visiting the street Those travelling to other destinations Car users (non-disabled) visiting the streett Disabled car users visiting the street …

Requirement for Street Elements

Crossing places

Traffic island

Street seating

Cycle stands

Cycle lane

Bus lane

Bus bays

Running lanes

Parking bays

Disabled parking bays

Loading bays

Pedestrians ● ●

Pedestrians who have mobility difficulties ● ●

Those using the street to socialise/relax ●

Cyclists ● ● ● ●

Bus users visiting the street ● ● ● ●

Those travelling to other destinations - all modes ●

Car users (non-disabled) visiting the street ● ● ●

Disabled car users visiting the street ● ● ● ● ●

Shopkeepers ● ●

Minimum Design Requirements

Existing Spaces

Design Spaces

Parking Bays 10 12

Loading Bays 10 14

Disabled Bays 2 4

Bus Stops 4 4

Crossings 3 3

Streetspace Option Generation Kit

Blocks – Colour and Size

• Use colour to denote different types of space usage

• Some based on current street colour categories; e.g. blue = disabled parking (blue badge)

• Size represents to scale space required to accommodate feature

Scheme Comparison

Differences in Provision by Option

Plan A Plan B Plan C

General Parking Yellow 4 4 10

Disabled Parking Blue 2 8 2

Loading Brown 2 2 2

Bus Stop Orange 1 1 1

Appraisal Spreadsheet

• Compares the impacts of various street designs on different user groups

• Inputs include desired and actual levels of provision for each street element

• Output is a comparison of the impacts for the various user groups

• Following example replaces 6 parking bays with a bus stop

User Impact Matrix

• Matrix indicates relevance of different street features to different user groups

• Impacts are only positive (1) or negative (-1);

the matrix does not include any weighting

Provision and Impacts

The screenshot shows the spreadsheet being used to show the impacts of replacing 6 parking spaces with a bus stop

Current plan elements are entered here

Proposed plan elements are entered here

Provision and Impacts

The impact matrix is used to calculate the impacts from the current provision and for the proposed plan

Spreadsheet Output

• Comparison shows there will be a positive impact for bus users and negative impacts for car users (including disabled car users)

• BUT this comparison did not take account of: – the relative importance of the user groups

or – the ideal or maximum numbers of elements

Adding User Group Weights

• The weightings in the matrix could be altered (e.g.) to favour plan options that:– Prioritise bus users– Prioritise disabled car users– Discourage car use by other groups

User group Original weighting Revised weighting

Bus passengers 1 5

Disabled car users

1 2

Car users 1 0.5

Revised Impact Matrix

• The weightings are then fed into the impact matrix……….

Bus user weighting

Car user weighting

Disabled user weighting

Street Element Weighting

• There may be an upper limit, or ideal number of a particular element

• The spreadsheet currently allows a maximum provision point to be set; after this point, increasing provision does not increase the benefit for any group

• It is possible to include other relationships, for instance diminishing returns

Setting a Cut-Off Point

Parking spaces

Uti

lity Adding extra

spaces does not increase the benefit

• In this example, the maximum number of parking spaces has been set at 6

Spreadsheet with Weightings

• The revised impact matrix now includes the following:

A. User Group Priorities:– Priority for bus users– Priority for disabled drivers– De-prioritising car users

• Cut-off point for parking spaces:– After 6 have been provided there is no benefit

from additional provision

The Effect of Weighting

• Weighted matrix:

• Unweighted matrix

Conclusions

• Spreadsheet currently under development, as an aid to option appraisal/selection – and to more targeted option generation

• Encourages more explicit treatment of objectives, priorities and needs

• More work required on inputs

• BUT, as yet, does not take into account location of design elements along a street

Value of Relative Location?

P 4 Bus Stop

Shops

Contact Details

• james@transport.ucl.ac.uk

• peter.jones@ucl.ac.uk