10 Minute Towns |Access i b i l i t y & Framework Repor t
3.3 Walking and Cycling Network Data
It is also possible to include public transport accessibility in the routable network using timetable information in General Transit Feed Specification (GTFS) format, which is useful for locations with frequent public transport services. 3.3.2 Proposed Improvement Network The proposed network was derived using the baseline catchment analysis undertaken in ArcGIS (as discussed in Section 3.4.2); where potential walking and/or cycling connection could be placed. These potential links were added to the existing street network to represent the proposed network in order to undertake the proposed catchment analysis. It should be noted that the proposed improvement networks are for the purposes of a high-level analysis of the three towns only. These improvement schemes are subject to further detailed analysis to understand their feasibility and viability.
3.3.1 Baseline (Existing Network) The street network utilised in the analysis was derived from Open Street Map data and imported into ArcGIS as a polyline feature. A high-level review of the existing walking and cycling network was undertaken on Google Maps and Google Streetview to verify the accuracy of the street network, as this would impact the catchment analysis for the study. Any missing walking and cycling links were then added to the street network prior to the catchment analysis. It should be noted that owing to the national Covid-19 travel restrictions in place in 2020, verification was only possible using online resources, although in addition Local Authority personnel reviewed the accuracy of the network. To conduct the analysis, an ‘end to end’ routable network must be created in a GIS package from the polylines forming the street network. The package used in this study was the Network Analyst extension within the Esri ArcGIS package. The routable network defines where it is possible to travel (indicated by the polylines representing streets), where it is possible to move between streets (indicated by the nodes where streets intersect), and how fast it is possible to move through the network (by defining an average speed for walking and cycling). Once these parameters are defined, the GIS package will be able to determine both the range that can be traversed and the time taken to do so within the extent of the network. Given that this is a pedestrian and cycle study, it is important to remove roads on which pedestrians and cyclists are not permitted (such as motorways) before creating the routable network.
18
Made with FlippingBook flipbook maker