Does it really matter that national recycling rates aren't accurate?

Recycling rates are the main tool used to measure the environmental performance of waste management systems and provide a key indicator which enables the four UK nations to be compared against one another (and other countries), as well as to track progress against targets. Recycling rates also hold a high degree of value for residents, local government officers and politicians, and people care about them because they underpin public trust in environmental policy.

However, recycling rates across England, Scotland, Wales, and Northern Ireland aren’t directly comparable. Each of the devolved nations has different policy drivers which impact on what their priorities for waste management are, for example in Wales its consistency of collections, in Scotland policies focus on circular economy reforms, and in England Simpler Recycling.

The additional challenge is accuracy, with continuing debates about where we take the measurement ‘recycled’. Under the present model, the recycling rate is calculated using the total amount of material collected for recycling less any contamination or rejected materials removed during the sorting process. A key challenge is that materials from different collection methods and sources undergo differing degrees of sorting prior to the point at which the ‘recycled’ measurement is taken. Therefore, some materials will have had a greater degree of pre-treatment and therefore a higher amount of contamination or rejected material removed, compared to others which may still have a greater degree of mixing.

A further challenge is that we measure the recycling rate too early in the material lifecycle, i.e. before it has been fully sorted and before it has passed through a reprocessor to create a new product. When you then also consider difficult to recycle streams (such as plastic films), which do end up in Refuse Derived Fuel or Solid Recovered Fuel due to the lack of viable markets to actually recycle these materials, the accuracy falls further. Let’s be clear, I’m not suggesting this is fraudulent data reporting, merely that a combination of methodological limits and policy choices have led to the approach we currently take.

Whilst purists will rightly argue that the current method is inaccurate and potentially grossly overestimates the amount of material which actually makes it into the manufacture of new products, does it really matter? Would uniform metrics actually improve environmental outcomes or just simplify comparisons? Does “bad data = bad governance”?

There is a strong argument to say that it does matter, if the recycling rates are overstated, there is a risk of rewarding box-ticking over real waste reduction, undermining accountability, leading to misleading success stories that may delay tougher reforms or erode efforts over time. Furthermore, it may impact international credibility. As such, recycling rates are a proxy and should therefore not be the sole goal of an effective waste management service. Measuring the carbon impact (although this has its own measurement challenges), waste reduction, and material reuse may be better or supplementary indicators, which could provide policy makers with a broader understanding of the overall performance.

Additionally, perfect data doesn’t guarantee better policy or better outcomes and over-focusing on accuracy can stall action by diverting resources from other initiatives to improving data measurement. The public believing recycling “works” matters more than whether it’s precisely measured, and there is also a risk of prompting cynicism if inaccuracies are highlighted or corrected without sufficient context. A significant drop in recycling rates due to an update in calculation methodology might risk undermining public confidence in recycling.

What ought we be measuring as well as recycling rates in order to better understand the performance of waste management systems? Carbon performance is the most obvious alternative; however, has many more challenges in its calculation than recycling rates, from how to calculate a carbon factor, to what to include in its measurement. It is also a more complicated measure to calculate when you start considering how you could account for differences in vehicle fuel, distances travelled, collection vehicle type, collection methodology, type of sorting technology employed, reprocessor methods, and displacement of virgin materials.

So… does recycling rate accuracy really matter? Yes, accuracy matters but not in isolation. The danger isn’t having imperfect data, but mistaking the metric for the mission.

The real question is whether recycling rates help us reduce waste, or whether they just help us feel better about it.