Trip Generation and Capacity Modelling

2 Introduction o Our role o Recommendations o Planning policy o Trip generation o Existing network traffic o Growth and assessment o Questions

3 Our role o Statutory consultee o Deadlines o Technical review of safety and capacity o Advice on sustainability and car parking o Will support any recommendations for refusal at appeal

4 Recommendations o Technical evidence required to support or resist o Reasons for refusal; o Severe cumulative residual capacity impact o Detrimental impact on highway safety o An unsustainable location

5 National Planning Policy Framework o Promotes sustainable choice o Requires Travel Plan to accompany submissions o Safe and suitable access o Cost effectively mitigate impact o Promotes plan-led development

6 Trip Generation o Trip Rate Information Computer System (TRICS) o Industry standard o Recognised and tested at appeal o Outputs require appropriate site selection parameters

7 Existing Network Traffic o Has to represent an ‘average’ day o Established through counts – auto, manual, video o WSCC have auto count locations which is used to define seasonal fluctuation o Detailed analysis will include turning data

8 Growth o Derived from Trip End Model Programme (TEMPRO) using data from National Transport Model (NTM) o Provides forecasts on population, employment, households, car ownership and traffic growth to a local level o Forecasts based on planning data, RPI data, ONS projections, census data etc

9 Cumulative Impact o Base network conditions have growth factor applied o Committed development flows can be added o An analysis of future year operation is undertaken

10 Junction Modelling o Industry standard programs used; PICADY, ARCADY and LINSIG o Requires the input of junction geometry, visibility and observed flows o Provides an assessment of the junction capacity, delay and queuing

11 In Conclusion o Assessment is in accordance with DfT guidance o Methods endorsed at appeal o Determines extent of impact and can assist in developing mitigation o Provides an evidence based assessment