UK water companies are starting to explore this option and are hitting huge regulatory barriers as the by-product is considered industrial effluent. It will require regulatory shift. I'm wondering if anyone has done the maths properly though. How much salt do we mine each year? And how does it compare to the salt produced by desalination? If the average consumption of water in the UK is 125 l, then we can compare the salt produced to the salt consumed per capita every day in the country (e.g. industrial use, salt spreading on roads, etc.).

The truth is that you'll never be producing 125 l for 69M people all from desalination. Only a very small fraction of the 125 l will come from desalination.

The challenge is being driven by climate change and stringent environmental legislation in the UK water industry. These challenges are creating large gaps in their water resource planning for their future water supply. Hence desalination and effluent reuse now being considered as options. Its all in the water company water resource plans that have been published on their websites.

And BTW, I don't fully understand why 3 people have down voted this post. Its an incredibly interesting topic.