The green infrastructure valuation toolkit user guide

Building natural value for sustainable economic development: the green infrastructure valuation toolkit user guide
In a study on the economic benefits of Boston’s parks by the Trust for Public
Land 135 , residents were asked to value their direct use of the open green space
for:
general use – such as walking
sports – for example cycling
special uses – for example golf.
The study found an average value attributed to each use of $1.9, $3 and $9
respectively (2006 prices).
ASSESSING THE BENEFITS
Qualitative assessment is based on the overall impact of the proposed investment
on recreation, on a scale of low, medium and high:
QUANTIFYING
low impact - improves the setting for existing recreational use
medium impact - improves access to public space for recreational use
high impact - provides an integrated approach to access and the
enhancement of recreational space.
In order to measure the benefit, the starting point is understanding the
relationship between the green infrastructure investment and the direct leisure
use that it enables. For example, the introduction of a new path or cycleway will
enable recreational use. The protection of wildlife or rivers will support uses such
as bird watching or angling.
There are a number of ways to estimate use by residents – two are outlined here.
If a user demand assessment has already been done, this can be used to
underpin the benefit assessment tool.
The estimate of the total number of users can either estimate an overall number
of users, or break the number down by different types of activity – for example
walking, cycling. Which approach is used will depend on the type of green asset
and the level of understanding of the end users.
Method 1
This involves analysis of the number of people in a catchment area - based on
varying distances from the green infrastructure - and the average frequency of
use.
total demand = total population in catchment x average frequency of use for the
type of activity
Census and other leisure surveys can be used to set an appropriate frequency of
use.
Method 2
An alternative approach is to estimate the population in a catchment area and
apply a participation factor and a frequency factor.
total demand = total population in catchment x participation in recreational activity
x frequency of use
MONETISING
The approach to estimating the recreational economic value of a particular green
project involves:
assessing the expected change in visitors as a result of the project -
based on a visitor demand estimate
assessing the ‘associated consumer surplus value’ – the willingness to
pay.
As there is often no market price for the recreational service - for example an
entrance fee or permit fee - an appropriate benefit transfer monetary value is
needed to provide a proxy for a persons’ willingness to pay.
A more sophisticated approach is the transfer function method. This enables
the transfer value to take account of the specific context – for example the socioeconomic
characteristics of an area. However, this requires that the study being
drawn upon has provided details on the willingness to pay. Alternatively, for major
green investments, a willingness to pay study could be done.
There are a number of key sources that summarise the results of benefit transfer
studies:
the most significant database is EVRI (Environmental Valuation
Reference Inventory*) – however it is not always up-to-date
new evidence may come from academic studies and evaluations by
Defra, the National Trust and British Waterways
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