For any treatment regimen to be successful, the water quality must be monitored and maintained. This is accomplished through a series of control tests carried out to ensure consistency and to prevent the development of waterside problems. These are typically done by the facilities’ operating personnel, the WTSC (water treatment service company) or both. It is an interesting development that some jurisdictions such as NYC now require cooling tower readings be taken three times per week, and bacteria tests weekly (to support Legionella prevention).
Testing frequency should be dependent upon system size, make-up water quality, stress level, and water system complexity. Some testing needs to be carried out routinely (daily or multiple times per week) with supplemental testing done less frequently. Routine basic testing should include as a minimum: confirmation of inhibitor reserves, presence of oxidizing biocide (halogen or ORP), and bleed control (conductivity). Remaining program control activities should be incorporated into a system’s PM regimen at a slightly lower frequency (perhaps weekly). These could include product inventory management, cooling tower inspections, bacteria testing, and feed/control equipment maintenance inspections. Beyond this, a higher plateau of testing at a reduced frequency can add important value and might incorporate material balance detection, metals concentrations, more involved microbiological screening, long-term corrosion studies or data trending.
The importance of effective water treatment cannot be understated. Although effectiveness is wholly dependent upon implementation, active operator involvement and good data derived from accurate testing.
John D. Caloritis, CWT
The Metro Group, Inc.