With 10,000 miles of water and sewer mains serving 1.8 million people in two counties, the Washington Suburban Sanitary Commission (WSSC) in Maryland is one of the nation's largest water and wastewater utilities. A bicounty political subdivision of the state, the utility is imposing a four-tier "inclining block" rate structure that raises the price of water as customers enter higher tiers of use. Instead of being charged at the highest tier of water used, customers will be charged only for the water used in each tier. The new rate structure is expected to lower quarterly bills for a three-person household using 55 gallons per person per day, WSSC's average household size.

The change was prompted by a Maryland Public Service Commission ruling that the current 16-tier structure is unduly preferential to low-usage consumers. It's also intended to better align costs with rates and provide a more predictable revenue stream to pay for infrastructure improvements. The Maryland Department of the Environment identifies the structure as a pricing strategy that encourages water conservation in compliance with the Maryland Water Conservation Act of 2002.

The process of developing the new rate structure, the first in 25 years, involved pricing and conservation experts and a consumer advocate. WSSC held more than 30 public hearings attended by 1,500 customers, which generated more than 300 comments. The meetings were livestreamed to nearly 2,500 viewers. “The selection of a modern and resilient rate structure marks the conclusion of a thorough and deliberate process that made public outreach a priority,” says WSSC Commission Chair T. Eloise Foster. “As we move toward implementation, we'll continue to reach out to our many stakeholders and keep them apprised of the policy and fiscal implications."

Approximately 93% of all WSSC bills are for residential customers. The new rate structure is expected to go into effect on July 1, 2019.