ARLINGTON - The city plans to install new sensors at Lake Arlington to identify contaminants, such as spilled gasoline, that could harm the water treatment system as well as detect whether someone has intentionally poisoned the water, officials said.The Arlington City Council is set to vote on about $250,000 in contracts tonight for phase three of the citywide water quality monitoring and event detection system project, which started in 2009.Arlington, the seventh most populous city in the state, already has spent about $1.3 million installing contaminant sensors at its water treatment plants and critical, undisclosed locations throughout the city that includes the entertainment district -- home to Cowboys Stadium, the Rangers Ballpark in Arlington, the Arlington Convention Center, Six Flags Over Texas and Hurricane Harbor."This is to protect our water system from an intentional contamination by terrorists," said Terry Benton, assistant director of operations for the city's Water Utilities Department. "It does offer us numerous other benefits. We can look at the water quality in those locations and we can see how our system is working."The Environmental Protection Agency worked with the city to identify where to place the sensors, which are designed to alert water utilities and public safety staff about potential contamination events that could harm the public. Sensors that constantly monitor the water supply system in the entertainment district were added in phases before the NBA All-Star Game in 2010 and Super Bowl XLV in 2011, both held at Cowboys Stadium, according to a staff report.Lake Arlington, which has more than 2,200 surface acres and holds an estimated 15 billion gallons of water, supplies drinking water to more than 500,000 people. The city plans to have the new water quality monitoring sensors in place there by next May.Benton said the monitors are designed to detect contaminants ranging from algae blooms to manmade toxins. That information will help staff fine-tune the water-treatment process, which could save the city on chemical and electricity costs."If we know what is coming into the plant, that will help us adjust our treatment processes to get the best quality of water that we can," Benton said. "Any time it rains we get run-off, which will allow pesticides and fertilizers to get in the lake. We can measure the severity and that will help dictate how we treat the water."Also, if a substance is detected in the raw water that can't be filtered out or could damage the filtration system, the sensors could alert the city to shut down the water treatment plant and divert the contaminated water to the wastewater system for disposal, Benton said.Benton said he was not aware of any such instances that required the plant, which already has contaminant sensors, to be shut down.The additional monitoring system was not prompted by the horizontal gas well drilling occurring beneath the lake, Benton said.In July 2010, a small amount of produced water from Quicksilver Resource's Olcott South drill site in Fort Worth leaked into Lake Arlington after the shutoff valve of the storage container was apparently left open. Arlington tested the water but found no contamination related to the spill, officials reported."It was far enough way from the treatment intake. We couldn't find anything tremendously wrong," Benton said.This report contains material from the Star-Telegramarchives.Susan Schrock, 817-709-7578Twitter: @susanschrock
The Arlington City Council's meeting will be 6:30 tonight at City Hall, 101 W. Abram St. To read the agenda, visit www.arlingtontx.gov/citycouncil.