Major enhancements evaluation meta-analysis

We've created dashboards that give an overview of evaluation findings across our Post Opening Project Evaluations (POPEs) of major enhancement schemes.   

Bringing together evidence from a set of evaluations enables insights at a programme-level.

Introduction

This dashboard shares findings of all published major enhancement POPE reports. This includes evaluations of projects that opened for traffic from 2002 onwards as part of:

• the Targeted Programme of Improvements
• the Major Projects Programme
• most recently, Road Investment Strategy (RIS) schemes. 

Historically, we've evaluated each project one year (1YA) and five years (5YA) after opening. The dashboard shows the most recent available evaluation. 

We're moving towards a single three years after (3YA) evaluation for each project. More recent and future schemes in the dashboard follow this approach. 

There's a lag between a project opening for traffic and the publication of an evaluation. As a result, evidence from the most recent schemes may not be available yet. 

The number of evaluations fluctuates with the size of our investment programme. The number of projects evaluated will grow over time. Currently there are 125 evaluations in our dashboard, however the sample size for each graph will vary as not all metrics are available for all evaluations.  Throughout the dashboard we only show categories which have at least three evaluations in them.

Background

We do this to:  

• demonstrate the benefits and impacts of our projects to our customers
• explain differences between forecast and outturn impacts
• provide evidence to verify or improve appraisal methods and tools we use to assess schemes before our final investment decision
• gain evaluation insights to inform future investment decisions
• give stakeholders confidence in our ability to deliver projects that provide value for money. 

When our projects work well, we celebrate success and replicate this elsewhere. 

When they don't, we are transparent and we learn and improve. 

We assess whether our investments deliver value for money and represent the best use of our limited resources. 

We're continuously improving our approach to evaluation, including refining our conservative value for money methodology.  

Key findings

• our schemes partially or fully achieved almost all their objectives
• we were very accurate in predicting our total costs
• typical schemes delivered high value for money – although lower than expected
• environmental outcomes at evaluation were generally as expected
• observed traffic was close to forecast levels, with a tendency to be slightly lower than forecast 
• our schemes improved journey times during the morning and evening peaks - but improvements were smaller than anticipated
• typically, our schemes improved journey time reliability
• safety generally improved for scheme extents and wider areas, with fewer personal injury collisions and lower collision rates

Further information

Read our Major Enhancements Evaluation Approach.

See individual project evaluations.

If you want to know more about evaluation in National Highways, please contact our evaluation team.