The City of The Dalles says its Wastewater Treatment Plant has discharged effluent that exceeds the plant’s limit for E. coli due to incomplete disinfection.  Sample test results on Friday morning indicated an E. coli exceedance.  Several resamples in the following 24 hour period confirmed that the disinfection is still incomplete.  The Dalles Public Works says the cause of the exceedance is still under investigation and rigorous water quality monitoring is ongoing.  The ultraviolet disinfection process has been ramped up to maximum capacity in an attempt to bring E. coli counts back within permitted limit, and the increased frequency of sampling 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 the West Mayer Park boat launch.  The signs say: “Warning – Contaminated Water – No water contact” and give phone numbers to call for information.