The move to circularity in our economy is often seen as being either too complex or too simple: total system change or do a bit more recycling.
The recycling and reuse of materials get more of the attention, but this focuses mainly on the technical cycle. I have spent most of my career working in the water sector and, while there is an important technical element, the biological cycle is the most important.
Water is the ultimate circular system and yet it has been neglected until recently. Those in the sector understand the importance of water as a system and have been working in ways that are truly circular for many years.
For example, the recovery and treatment of sewage sludge and processing it back for the land is commonplace. Not only is it a recycling practice but a regenerative and restorative one as well.
Assets in the water industry are kept in circulation for as long as possible, and much longer than they were originally intended in many cases, showing the ingenuity and resourcefulness of the people who work in the sector.
As for the scale of the problem of infrastructure renewal: how to you replace a dam, for example? How do you replace hundreds of miles of water pipes that have new towns built over them?
How long do you keep up maintenance for before it becomes uneconomical or causes problems? What do we do about lead pipes that carry drinking water?
Understanding the catchment has become an increasingly important part of any water business. We have always known the importance of understanding what goes on in our catchments; who is discharging what to where.
But, increasingly, the effects on water quality come not just from industry but agriculture and our homes too. In this way, water could be seen as an indicator of practices that may work now but could be unsustainable in the future.
If the products that we put in the sewers contain elements that are difficult to remove, perhaps we should reconsider their use.
Water is critical to life and should be considered at the heart of the circular economy.
I look forward to seeing increased collaboration between water, resource management and energy. If we work together we have a better chance of innovating and transitioning to a more sustainable future.
Mark Smith is the Chief executive of the consultancy WRc