For information contact: Julia Patterson (206) 296-1013
                                   Kathy Lambert (206) 296-1003

The Metropolitan King County Council today approved a list of candidates for local pilot projects aimed at reducing the volume of fresh water flowing into King County’s sewage treatment system.

All local sewer systems in King County (except Seattle) collect wastewater in a separate system from storm water. Some of the storm water, which comes from leaking pipes, manholes and inappropriate downspouts and pipe connections, collects in the regional wastewater conveyance system and becomes part of the wastewater treatment process.

Local agencies and the Metropolitan Water Pollution Abatement Advisory Committee selected the 29 projects as part of the Regional Infiltration/Inflow Control Program. The program, part of the Regional Wastewater Services Plan, will test the effectiveness of various techniques to reduce the amount of surface and groundwater reaching the County’s regional wastewater conveyance system.

“Seventy-five percent of the flow into County treatment plants during peak rain events is freshwater coming into the system through our conveyance pipes,” said Councilmember Julia Patterson, Chair of the Council’s Utilities Committee. “The extra volume strains the regional wastewater system and forces the County to treat groundwater, which reduces the efficiency of the treatment plants. The goal is to find an effective way to keep fresh water from mixing in with sewage on its way to the treatment plant, and we need to look at all the options available.”

From the 29 projects, local agencies and the Metropolitan Water Pollution Abatement Advisory Committee will select 10 programs for further development and possible implementation this year.

“This list is an example of the County and its regional partners working together on a problem that affects us all,” said Councilmember Kathy Lambert, Chair of the Council’s Regional Water Quality Committee. “It’s acknowledging that when one area of the wastewater treatment system is affected, the impact is felt throughout the region, so looking for solutions has to involve every part of that system.”