Source Water Monitoring - City of Columbus

Project Overview

In the early 1900's Columbus gained national prominence in the water quality industry when the Hoover brothers developed water treatment methods to reduce typhoid which had been prevalent during that era. Since then, water quality monitoring of the Scioto River and Big Walnut Creek has been an integral part of the drinking water treatment process at the Columbus Water Treatment Plants.

The Scioto River begins as a small creek about 80 miles north in Hardin County, northwest of Kenton, Ohio. Rolling through woods and farmlands, this river remains a main water source for Columbus. The Griggs and O'Shaugnessy Reservoirs, located on the Scioto River, have a combined storage capacity of 6.2 billion gallons, holding only a small percentage of the water that flows through Columbus, and providing water for downtown, west and northwest Franklin County.

Big Walnut Creek forms about 20 miles northeast of Columbus and feeds Hoover Reservoir, which is named after the Hoover brothers. This reservoir can hold 20.8 billion gallons of water; it supplies water for the entire northeast portion of Franklin County.

To ensure quality drinking water standards, Public Utilities officials asked Fondriest Environmental to supply and install real-time data telemetry systems that would monitor water quality along the Hoover, Griggs, and O?Shaugnessy Reservoirs.

System Description

Fondriest application engineers installed two NexSens cellular data telemetry systems at drinking water intakes - one near the Hap Cremean Treatment Plant and one near the Griggs Treatment Plant - to allow City personnel from the Water Quality Assurance Laboratory to constantly monitor the water quality. YSI 6600 Extended Deployment System sondes with temperature, conductivity, pH, dissolved oxygen, turbidity and chlorophyll sensors are connected to the cellular systems and data is transmitted at hourly intervals to the lab. The data is then posted to a secure website, where authorized City employees can access the data 24/7. Graphs, data tables and statistical reports are available on-line for analysis.

At Hoover Reservoir, Fondriest engineers installed a YSI profiling system as a means of measuring water quality parameters throughout a vertical column. An integrated winch and drive mechanism automatically raises and lowers the water quality instrument, which traverses the water column four times daily. The water quality instrument, a YSI 6600 EDS sonde, measures temperature, conductivity, dissolved oxygen, pH, turbidity, and chlorophyll at 1 meter intervals, while an integral pressure sensor records the depth of each measurement.

Rich Rutherford, Water Research Analyst for the City of Columbus Division of Water, stated..."The benefits of the platform include improved process control at the plant, chemical cost reductions, security monitoring, and customer satisfaction in taste and odor control. Additionally, the improved understanding of our reservoir?s limnological life cycle will help to secure its reliable use for future generations in Columbus." This ongoing testing and monitoring assures that Columbus drinking water will be of the highest quality, meeting all EPA and SDWA standards.