So-called “flushable” wipes and diapers are creating havoc with Ripon’s wastewater treatment plant by plugging up the system.

That’s what Public Works Director Ted Johnston told Ripon Rotarians at a recent meeting at the Spring Creek Country Club Wednesday.

Johnston pointed out that the Ripon sewage operation is simple and basic in its design and costs the homeowner less than other nearby communities. Treatment ponds are located near the Stanislaus River to the south of the community.

The ponds help support four varieties of birds that eat the bugs in the treatment plant as do turtles and Canadian Geese.  

He explained that the ponds are lined with clay to prevent the sewage water from getting into the ground water. Oxygen is put into the water to promote the growth of cleansing bacteria.  He added that storm drain water is kept completely separate.

The head works of the system is where items like flushable wipes, diapers and even Swiffers floor cleaning pads are screened out of the water flow before getting into the ponds.  After the head works the flow goes into the first pond where it remains for 35 days.

The operation uses six aerators that also add oxygen to the water in the separate ponding areas. 

“We have always had land available (for drainage) and the city has taken advantage of that for the system,” Johnston said.  “None of that water goes into the river as is the case with more costly systems.”

Asked about having odor from the ponds, Johnston said the city has had only one or two complaints a year with the industrial ponds usually being the source.  The city spends some $60,000 a year in monitoring and analyzing the ground water for the state.   He added that the ground water depth near the river is between six and eight feet with drinking water being 100 feet below the surface and the treatment ponds are about eight to 10 feet deep.  

As for the sewer line through the city, the system was originally constructed using wooden piping and later clay that can crumble if it wasn’t installed correctly, Johnston said.  Some of the piping has had to be replaced in the community usually after a problem with tree roots is discovered. 

He noted that the old downtown stores in the 100 block of Main Street had large septic tanks serving several of the original stores.  

To contact Glenn Kahl, email Gkahl@mantecabulletin.com.