Delineating Functional Territories
Delineating Functional Territories Research Project
Spatial policy in Ireland, as set out in the National Spatial Strategy (NSS), places a strong emphasis on the exploitation of complementarity, both among urban centres and between urban and rural areas, in order to achieve the ‘critical mass’ which the NSS sees as a vital prerequisite for sustainable and balanced development. Implementing this approach requires detailed knowledge of the workings of the Irish space economy, one of the main organising elements of which is the functional region. To date, the main focus of implementation of the NSS has been on the so-called ‘gateway’ urban centres, for which an investment priorities study has been undertaken and an investment fund established. However, before significant amounts of public money are committed to infrastructural and other developments in the cities, we need to know a lot more about the likely impact of that investment, not just in the cities themselves, but also in their linked towns and rural hinterlands. In short we need to know more about patterns of urban functional specialisation and urban functional regions.
AIRO and ICLRD have started a research project aimed at mapping a series of functional areas for towns and cities across the island (north and south). To date a number of themes have been developed:
- Natural Catchments (Huns and Gateways)
- Network Travel Catchments
- Service Infrastructure Accessibility
- Travel to Work Catchments
- Urban Functional Specialisation
- Retail, Hospital and Cultural 'Huff' Gravity Modelling
- ESDA Population Accessibility
- House price mapping
A series of maps have been developed to show the natural catchment or ‘potential catchment’ of Gateways and Hubs in both the Republic and Northern Ireland.
Network Travel Catchments:
A series of drive-time catchments have been created for all towns in Ireland (North and South) with a population greater than 500 people. The catchments are based on an analysis of travel times across the road network. Catchments have been created for 585 towns (401 in the Republic and 184 in Northern Ireland).
Service Infrastructure Accessibility:
As part of a wider research project ICLRD has been involved in conducting the first in-depth spatial analysis of community accessibility to public services in Northern Ireland. The datasets collated and methodologies developed for this exercise, have also being applied by ICLRD to services in the South - and useful evidence is beginning to emerge that should help the policy development community in both jurisdictions.
Travel to Work Catchments:
The development of catchments based on the travel to work trips of the working population is a useful way of understanding the employment strengths of urban centres in a local, regional and national context. There is much anecdotal evidence of workers undertaking long commuting journeys to work in both the Republic of Ireland and Northern Ireland. In recent years the availability of high levels of job opportunities in the Republic has resulted in an increased level of cross border commuting to employment destinations. As part of this study an attempt has been made at mapping the commuting patterns to urban centres in both jurisdictions. Further research is also underway to explore specific levels of cross both commuting from the Republic to the North and vice-versa.
The primary sources of origin-destination (OD) employment data required to undertake this research are collected by the main national statistical agencies, the Central Statistics Office (CSO) in the Republic and the Northern Ireland Statistical Research Agency (NISRA) in the North. OD data in both jurisdictions are collected almost entirely independently of each other and little or no data is recorded for destinations in either jurisdiction. OD data is available for the Republic of Ireland in 2002 (15% sample) and a complete coverage is available in 2006 through the POWCAR dataset. The Northern Ireland OD data is available through the 2001 Census outputs.
Republic of Ireland
The Place of Work Census of Anonymised Records (POWCAR) is a detailed dataset developed by the Central Statistics Office (CSO). The dataset contains details on the origin and destination, along with a series of additional attribute data, of all those ‘At Work’ at the time of Census collection in 2006. With over 1.8 million records in the dataset it is a very rich source of information that can be used to depict the daily mobility patterns of the workforce within the Republic. Individual records have been aggregated to represent levels of interaction from origins (Electoral Divisions) to destinations (Urban Centres – Gateways, Hubs, Other Towns and Northern Ireland Counties)
The Origin-Destination data available for Northern Ireland is a by-product of the 2001 Census for the United Kingdom. The matrix contains information on the number of trips from every Ward in Northern Ireland to all Wards in the UK. Catchments have been created for all Gateways and Hubs in the North.
Exploratory Spatial Data Analysis of Population Accessibility:
Population accessibility has long been regarded as a critical ingredient in locational and regional development studies; Harris (1954). Measures of population accessibility offer a useful way for estimating the relative potential of a given location at a national scale. Such measures paint a vivid picture of the impact of population dynamics and redistribution on aggregate levels of access, and how these developments can create economic opportunities for given locations over time.
We undertake an exploratory spatial data analysis of population accessibility as per O’Kelly and Horner (2003), where the calculation and visualisation of accessibility indices with GIS help us to explore spatial population issues.
'Huff' Gravity Modelling:
Following the approach of the Natural Catchments research (section 2) it was decided to further develop this work and produce a series of gravity based catchments for each Gateway. A gravity based catchments has been produced for three sectors: Retail, Hospitals and Culture. This work has initially been undertaken for the Republic of Ireland alone but recently the research team have create an All-Island Retail Gravity model.
This analysis is based on two main datasets; a travel time from each ED to each Gateway and a proxy for the strength of Retail, Health and Cultural activity in each Gateway. The proxy for the strength of sectoral activity in each Gateway has been developed using a special tabulation from the 2006 POWCAR data. The POWCAR data output used in the model relates to the number of people working in each Gateway who are involved in Retail, Hospitals or Cultural activity.
House Price Mapping:
Simply put, ED-level house price data is the missing link in Irish regional research. It offers the potential to distinguish between EDs based on house price differences, and can be used to proxy variables such as ED level wealth and ascertain ED-level housing stock and housing type. Republic of Ireland data on house asking prices can be linked with similar Northern Irish data (adjusted for currency) to create an all-island picture. House price data also allow one to empirically test various theories emanating from the Economic Geography literature that emphasise regional variation in prices and wages arising from core/peripheral location and ease or difficulty of travel-to –work commuting.
The final report on this project will be available shortly on the ICLRD website.
We are currently setting up the term of reference for a Phase 2 project that will focus on a cross border study area that links Sligo and Enniskillen. Details to follow.