The Bellevue City Council will have a short timeline to communicate to the King County Executive’s Office its concerns about proposed 2015 increases for wastewater and capacity rates they hope may be alleviated ahead of June action by the King County Council.

King County Executive Dow Constantine proposes a 5.6-percent increase to the county’s sewer rate to $42.03 per month and a 3-percent increase in the Wastewater Treatment Division’s capacity charge to $57 for new connections. Tim Aratani, finance and administrative services manager for WTD, told Bellevue councilmembers 2015 operating expenses are expected to increase by 6.5 percent to $135 million and again by 4.7 percent in 2016. The sewer rate is expected to remain flat in 2016. The wastewater treatment division plans to spend down its reserves, tackling a $4 billion outstanding debt for capital projects and related additional staffing, and expects to reach rate stabilization by 2017, Aratani said.

Councilmember Kevin Wallace said the WTD has loaded on too many projects, and the rate increases being brought on by them is too high for jurisdictions within the regional system to take. He added there is also an issue of equity, where someone living in a “mega-mansion” pays the same rate as someone in a “rambler.” He said there should be a way to correct this and make sure everyone is paying their fair share for the service.

Mayor Claudia Balducci said she wants more information about how the city’s contribution to the Our Waters program will be used in 2015. The Washington Supreme Court cleared the county to use the program for water quality improvements last year, following a legal challenge in 2008.

Pam Elardo, director of King County’s Wastewater Treatment Division, said the bulk of costs facing WTD for service are not related to an increase in water flow, but increases in loading — the solid matter in wastewater — that is being brought on by increases in population.