Expanding Sites
This data should be used to ascertain the potential
for reducing single occupancy car use and the number
of journeys, and for increasing the use of walking,
cycling, public transport and car-sharing as relevant
to the site’s circumstances and Travel Plan
measures to be implemented.
B1)
Baseline Calculation –
i)
Before Survey
To establish the baseline mode split of employees/visitors,
a before survey is required for each location. This
information will assist considerably in the setting
of appropriate trip rate and mode split targets.
The survey should, wherever possible, be performed
before the implementation of proposed Travel Plan measures,
preferably over one period of one day in March, April,
May, June, September or October (the survey should
be long enough to capture 95% of trips to and from
the site over the survey day). School holidays should
be avoided. For some sites additional weekend surveys
may be required. In agreeing to the Travel Plan monitoring
methodology, the organisation whose Travel Plan is
to be monitored also agrees that the monitoring can
take place unannounced, within a pre-specified period
of 4 weeks.
Each survey must be commissioned by the appropriate
local authority and should be carried out by an approved
independent specialist survey organisation. This should
not include any organisation associated with the site,
or any business employed by the organisation tasked
with developing or implementing the Travel Plan.
The local authority should approve the specialist survey
company and may chose to commission either:
- TRICS® to manage and undertake
the survey;
- A preferred survey company/
contractor; or
- Utilise an internal capability.
In each case the survey will need to be validated
by TRICS® to ensure it meets the required standard.
TRICS® will undertake a comprehensive validation
exercise before authorising the survey. No survey will
be accepted until it has met the validation criteria.
Each survey will be made available to the appropriate
LPA (local planning authority), LHA (local highway
authority), HA (Highways Agency) and local organisations.
It will also be made publicly available in the following
2 yearly TRICS® data release.
Different types of survey will be required
dependent on the circumstances of the site,
as shown in the table below. TRICS® can provide advice and/or undertake
a site audit to specify the survey requirements. TRICS® can
provide advice and/or undertake a site audit to specify
the survey requirements (see costs below [hotlink ‘costs’ to
later section]).
| Site
Type |
Survey requirements |
Contained
- Small number of site access/
egress
- Public transport services
run onto site
- Little off-site parking
- Travel plan aimed at all
site users
|
Fully classified manual observational
count – all vehicles,
vehicle occupancy and pedestrians
entering site counted
|
Non-Contained
- Significant off-site parking
- Some public transport
use not observable from cordon
- Many access/ egress points
- Travel plan aimed at all
site users
|
Mixed fully classified manual
observational count and selective
interview surveys – as
above, but also with interviews at
some cordon points.
|
Complex
- Mixture of off-site parking
locations
- Public transport use not
observable from cordon
- Large number of access/
egress points
- Travel plan aimed at only
one site user group
(e.g. staff
but not visitors)
|
Mixed fully classified manual observational
count and interview surveys – as
above, but also with interviews at
a majority of cordon points.
|
Note: Please contact TRICS® Survey Programme
Manager Ian
Coles to determine appropriate
survey technique.
B1) Baseline
Calculation –
ii)
Estimate Trip Generation – see
A1
A trip generation estimate will
need to be calculated for the additional
development proposed for the site. Data from
the before study will be required to calculate
the increase in trips.
The relationship between an expanded site and
trip generation is complex and very rarely
can a direct extrapolation of existing ratios
of trip rates be used. For example, an expansion
of sites as varied as a factory, school, or
business park, would not necessarily imply
a need to increase the trip rates for support
services, delivery vehicles, teachers or managers.
Therefore care must be taken to adopt a logical
and transparent methodology that can be explained
concisely in a manner easy to understand.
B2) After Survey – see
A2
B3) Analyse Survey Results – see
A3 |
