Isonomia has been covering questions around both marine and land-based litter for some time. To judge by recent press coverage, one of these is really interesting right now, and the other isn’t; the first being the domain of surfers and cool outdoorsy people and the second of the curtain twitching neighbour.
However, they are intimately connected for obvious reasons: a lot of marine litter will originally have been littered on land. Although a subject of hot debate amongst litterati, there are good reasons for thinking that globally the majority of marine litter originates from land based rather than sea based sources. 80% is the figure usually cited, although in Europe the percentage is likely to be a little lower as waste management tends to be of an overall higher standard than it is globally.
Much of Eunomia’s work to date on litter has involved pulling together the available data and making sense of it so that we can build cases for action more effectively and enable better decisions to be made about what to do. Over time, we’ve come across data that helps us to understand how much it costs to clean up litter in different places, and I think it tells an interesting story.
A tidy sum
One project to have captured the public’s imagination – while attracting some expert scepticism – is the Ocean Cleanup. The idea is to use arrays of floating booms to filter out plastic from the surface waters of the sea. The project’s feasibility study estimated that the cost would be around ~€4,500 per tonne, taking into account most (though not all) of the initial capital outlay and operating costs.
When it comes to dealing with the problem on land, there are few published estimates of what it actually costs to pick up street litter per tonne. For Eunomia’s work on the direct and indirect costs of litter in Scotland, we therefore had to produce fresh estimates of national clean-up costs for litter, as well as the overall tonnage. Putting the two together gave us a rough estimate of around €1,700 per tonne. It’s certainly eye-opening to compare this figure with the net cost of collecting waste from households, which is typically in the low hundreds of Euros per tonne.
Given this huge cost differential, there’s every reason to look for measures that will reduce litter, and move the material into cheaper collection systems – ideally destined for recycling rather than as part of ‘black bag’ residual waste.
However, while increasing recycling is a good thing in itself, it’s not necessarily the case that measures intended to achieve this would always be likely to affect littering rates. Any increase in kerbside recycling will in large part come from diverting material that would otherwise have been put in the residual stream, while littering, by contrast, typically occurs away from home. Accordingly it has been suggested that developing new on-the-go recycling infrastructure would have a significant positive effect in helping to reduce littering, but the behaviour change required to address littering in this context is actually quite different: not switching between bins, but using any bin at all.
Picking up the bill
From this brief overview of the available data – which is unfortunately scant – we can conclude that, per tonne, it could be nearly 10 times more expensive to clean up land based litter than to deal with it in the first instance through proper waste disposal channels. What a terrible waste of money the need to clean up litter is!
It also seems pretty clear that it’s nearly twice as expensive to clean up litter from the ocean as it is to collect it on land. The latter, of course, prevents litter from entering the ocean in the first place, avoiding all of the negative impacts that then result. My guess is that as better data on the comparative costs becomes available, the difference will in fact be revealed to be much bigger.
It’s a real challenge to quantify anything to do with litter, but by piecing together what data we have we can start to see things more clearly. In the future, I hope that we’ll be able to compare the cost of prevention measures against clean up measures, and here it’s likely that the difference in cost effectiveness will be even more stark.