Building a profitable water treatment technology business is hard, really hard. The obstacles are really too numerous to list here, but lets just say that every water is different, and while opportunities are everywhere there is no easy route to each highly distorted market.
You can realistically expect that it will take fifteen to twenty years from demonstrating a viable technology at lab scale to hitting break-even from a financial perspective. On that journey many tens of millions of dollars of investment will be required.
So why do it?
Well barriers-to-entry work both ways. Look at reverse-osmosis, a sixty-year old technology which is still unchallenged and which almost certainly has another forty years to run. So you may have a twenty year ramp-up, but a one hundred year pay-off period looks pretty good.
Also everyone knows that water is a strategically important sector and if you can achieve the holy grail of demonstrating the technical and commercial viability of a disruptive technology you can expect some pretty impressive multiples.
Finally there are a number of natural exit points in the evolution of a water technology. If you take the Lean Startup approach of proving hypotheses then you add value to the company and create an exit point each time a hypothesis is proven.
What ever you do though, don’t invest a few million dollars and expect to have J-curve growth on your hands in two years…because it won’t work and it will leave everyone in a bad place.