PLEASANT PRAIRIE — The Village Board voted Monday to create one sanitary sewer district for the whole community, continuing a consolidation effort needed to comply with the approaching end of a 20-year-old Great Lakes water diversion.

The move shouldn’t affect residents’ sewer bills — at least for now, Village Administrator Michael Pollocoff said.

The board voted unanimously to dissolve the village’s Sanitary Sewer Utility District D, an area on the northwest corner of the village, roughly bounded by Highway 50, Interstate 94 and Highway C.

That area will be combined with the Lake Michigan District to create a new Pleasant Prairie Sewer Utility, which will cover all village areas where sanitary sewer service is available.

Pollocoff said this will allow the village to shut down the District D treatment plant near 103rd Avenue and Highway C, which discharges treated water into the Mississippi River watershed via the Des Plaines River.

After the plant closes at the end of next year, sewage generated in that area will be pumped to the Kenosha Water Utility’s wastewater treatment plant on the lakefront, which services the rest of the village. The village also plans to close a second treatment plant, near 80th Avenue and 126th Street.

That’s a requirement of the diversion that was approved in 1990 by the governors of the eight states bordering the Great Lakes.

The village, which was seeking to eliminate dependence on radium-contaminated wells, was allowed to serve Mississippi watershed properties with Lake Michigan water on the condition that all treated wastewater is sent back to the lake by Dec. 31, 2010. The subcontinental divide that separates the two watersheds runs north-south through the village, roughly between 39th Avenue and Green Bay Road.

Pollocoff said the village does not plan any sewer rate changes for next year. In 2011, however, he said village customers will begin paying whatever rates are set by the Kenosha Water Utility, from which the village purchases wholesale treatment services.

No residents turned out for a public hearing on the change Monday night.

Pleasant Prairie’s existing Lake Michigan sewer district will continue to exist in just one area, outside of the village, where a small pocket of Somers “B Area” residents receive Pleasant Prairie services under a 1989 boundary agreement.

Trustee Steve Kumorkiewicz asked why the city could not serve these Somers islands, which are surrounded by city territory.

Said Pollocoff: “The city would take care of it, if people were willing to annex.”