City of Austin Performance Report 2014-15

Drinking Water Quality: Turbidity

Measure Description
One way to measure drinking water quality is to examine the turbidity or Nephelometric Turbidity Units (NTU). This measure indicates the relative clarity or the clearness of the water, and indicates the presence of suspended solids like clay, silt, plankton or other contaminants.  Austin Water (AW) attempts to achieve the lowest NTU possible, to ensure potable drinking water safety. It is also an excellent measure of plant optimization to ensure maximum public health protection.
Calculation Method
The finished drinking water turbidity is measured with a bench top turbidity meter at each Water Treatment Plant every four hours, and continuously monitored by online turbidity meters. AW reports the readings to the Texas Commission on Environmental Quality (TCEQ) for every four-hour period the Water Treatment Plant is treating water. Maximum possible readings of 186 are collected for each Water Treatment Plant and appear on the Monthly Operating Report (MOR).
FY 2014-15 Results
The goal for this measure is 0.10 NTU. The AW 0.08 NTU result was under the TCEQ level of 0.30 NTU by 0.22 and under the AW goal by 0.02. The lower NTU means the quality of water produced has a higher fine-particle removal rate. The NTU is below the permit level again due to improvements in plant chemical monitoring, filtering and treatment processes.
Assessment of Results
Austin’s drinking water NTU of 0.08 is well below the state standard level of 0.30 NTU. TCEQ monitors the permit level for NTU at 0.30. Continuous improvements in plant maintenance, operations and treatment processes continue to provide consistently high quality drinking water to customers.
An image of the Drinking Water Quality Report
Next Steps
The City of Austin draws water from the Colorado River into three water treatment plants: Davis, Ullrich and Water Treatment Plant 4. Davis Water Treatment Plant was constructed in 1954 and Ullrich Water Treatment Plant was constructed in 1969. Water Treatment Plant 4 became operational in FY 2014-15 and draws water from Lake Travis (Colorado River), providing an additional capacity of 50 million gallons per day. AW will continue to operate and maintain the plants in a manner that ensures high quality drinking water.
Contact Information
For more information contact Mehrdad Morabbi, Treatment Manager, at (512) 972- 0159.