There are two things.
First, the insurance companies are already running their models in secret. There are a number of them across Canada. They're all different, and I don't think any of them are very good. Some people were being charged for floods they shouldn't have been charged for.
Second, if we can predict floods, we can reduce damages, and that should reduce costs across the board. Imagine what the damage to crops would be, due to other events as well, if we had no weather forecasts at all. It's the same thing with flood forecasts. If we can reduce damages this way, we should be able to reduce insurance costs.