We don't need an international framework for sand extraction

Economists define common resources as resources that are rival (meaning that one person's use of them reduces the amount of the resource that is available for everyone else) and non-excludable (meaning that it is not possible to stop people from using them - if they are available to anyone, they are available to everyone). When thinking about common resources, we often think about the obvious examples like trees, or fish (in fact, that's an example I spend some time on in my ECONS102 class). But what about sand? Nature reported back in July (footnotes omitted):

Sand and gravel make up the most extracted group of materials, even exceeding fossil fuels. Urbanization and global population growth are fuelling an explosion in demand, especially in China, India and Africa. Roughly 32 billion to 50 billion tonnes are used globally each year, mainly for making concrete, glass and electronics. This exceeds the pace of natural renewal such that by mid-century, demand might outstrip supply (see ‘Global scarcity’). A lack of knowledge and oversight is allowing this unsustainable exploitation.

Desert sand grains are too smooth to be useful, and most of the angular sand that is suitable for industry comes from rivers (less than 1% of the world’s land). This extraction of sand and gravel has far-reaching impacts on ecology, infrastructure and the livelihoods of the 3 billion people who live along rivers (see ‘Shifting sands’). For example, sand mining on the Pearl River (Zhujiang) in China has lowered water tables, made it harder to extract drinking water and hastened river-bed scour, damaging bridges and embankments.

Is sand a common resource? It is rival, since one person using sand means that the sand is not available for anyone else to use. Is sand non-excludable? Possibly yes:

Most of the trade in sand is undocumented. For example, between 2006 and 2016, less than 4% of the 80 million tonnes of sediment that Singapore reported having imported from Cambodia was confirmed as exported by the latter. Illegal sand mining is rife in around 70 countries, and hundreds of people have reportedly been killed in battles over sand in the past decade in countries including India and Kenya, among them local citizens, police officers and government officials.

If essentially anyone can extract sand, then it is non-excludable. So, it seems that sand is a common resource, as defined by economists. Common resources suffer a potential problem, known as the 'Tragedy of the Commons'. The private incentive for sand harvesters is to harvest as much sand as they can, in order to maximise their profits. However, the social incentive is to harvest sand in a sustainable way (to ensure that sand is always available). This leads to over-harvesting of sand, and threatens the collapse of the resource.

Solutions to the common resource problem involve making the resource excludable. This could include regulation (with enforcement) or assigning property rights. Either of those options make the common resource excludable, since they define who is allowed to use the resource. They make sense as solutions when we are talking about trees or fish, because if the solution is enacted before the population collapses entirely, the population can recover. However, sand doesn't reproduce, at least not on the same timescale as trees or fish.

That makes a solution to the common resource problem for sand particularly difficult. The Nature article posits seven components of a sustainability plan for sand:

1. Source - finding new sources of sand, such as in Greenland;
2. Replace - finding alternatives to using sand, such as crushed rock;
3. Reuse - using crushed demolition waste and concrete as an alternative to new sand;
4. Reduce - cutting the amount of concrete use;
5. Govern - an international framework to control sand extraction;
6. Educate - making sure people know that sand is running out; and
7. Monitor - keeping better track of available sand resources.

That seems like a lot of effort, but it made me wonder - why are we worried about this? I can understand worrying about trees or fish - if a species of tree or fish is over-extracted to the point of extinction, that tree or fish is never coming back (unless we develop Jurassic Park technology). However, sand is created by weathering and erosion of rocks. So, if sand runs out, we just have to wait for more to be created (or we have to make our own).

Moreover, if natural sand becomes scarcer, the price of sand will increase. That price increase creates incentives to find alternatives to using natural sand. We already have alternatives (crushed rock or recycled demolition materials) - they are just more expensive than natural sand right now. The same thing happened with rubber. When access to cheap natural rubber was disrupted during both World Wars, that spurred the adoption of synthetic rubbers (which were already available, just more expensive).

We don't need an international framework to control sand extraction. Sand isn't going extinct.