New requirements to remove nitrogen and other nutrients from city wastewater will impact the rates that Billings property owners are charged on their water and sewer bills, with some businesses being hit particularly hard.

Every two years the city performs a rate study to evaluate whether what it charges for water and sewer treatment is keeping up with costs. The study calls for small increases for residents and higher increases for businesses and industrial users. 

Hardest hit will be businesses that are classified "high-strength commercial," which includes places like bakeries, restaurants and grocery stores, said Jennifer Duray, public works deputy director.