Ashland PWD Water Quality Lab

Ashland is able to safely discharge wastewater effluent into Lake Superior thanks to the quality assurance from the lab.

The lab tests for parameters determined by the DNR. This includes temperature, pH, Biological Oxygen Demand (BOD), Total Phosphorous (TP), Total Suspended Solids (TSS), Total Volatile Solids (TVS), Fecal Coliform, and E. coli.

Temperature is measured by a thermometer from both influent and effluent composites. Frequency of reading is dependent on rate of flow; higher flows get read more often.

Biological Oxygen Demand (BOD) is measured by optical probe. The probe reflects light into the water and reads the reflection. This is measured daily, from influent and effluent, plus other sites. Approximately 100-300 mg/L oxygen is needed to sustain life.

Total Phosphorous (TP) is tested once per week and must be less than 1mg/L. Aluminum sulfate (alum) is added to remove excess phosphorous.

TVS (total volatile solids) are also measured from samples.

Fecal coliform is tested once per week from the effluent. The limit is 400 (on monthly average). A yellow reaction indicates a positive result of fecal coliform.

E. coli is also tested weekly. The sample glowing under UV exposure indicates a positive result of e. coli.

No chemicals are used for the treatment of the wastewater. Rather, Ashland uses UV bulbs. The most troublesome part is keeping the bulbs clean; there are automatic wipers on the bulbs, but they are also removed periodically for cleaning.

All of this testing is done by the lab manager, Brian! He has worked with the City for 14 years, and his favorite color is blue :)

Daily tasks of the lab manager include a lot of solo sample testing, with the occasional trip "into the field" to help fill in or to accomplish other tasks. To work in the lab one needs accuracy, attention to detail, and the ability to always be engaged.