The Dalles Wastewater Treatment Plant has discharged effluent that exceeds the plant’s limit for E. coli due to incomplete disinfection.  The Dalles Public Works Department says sample test results from Monday morning indicated an E. coli exceedance, and several resamples in the following 24 hour period confirmed that the treatment process is not under control due to an upset in biological processes.  The ultraviolet disinfection process has been ramped up to maximum capacity in an attempt to compensate for partially treated effluent due to the upset, and sampling is being increased until E. coli counts are back within permit limits.  Samples will also be taken at pre-arranged locations in the river to provide data on the effect of the discharge on water quality in the river.  Signs have been placed at locations of public river access on the Oregon shore of the Columbia River, from The Dalles Riverfront Park to West Mayer Park boat launch warning people not to have contact with the water in those areas.