Some people will see their insurance premiums rise -- or fall -- under changes to how Tower Insurance assesses risk

The company's using new mapping to ensure landslide and sea surge risk is directly reflected in premiums.

90-percent of customers will see premiums drop, by an average of 70-dollars a year.

But the remaining 10-percent will see premiums rise.

Tower won't say what the average price hike for those customers will be -- as it will vary widely -- but the median rise will be about 230-dollars a year.