Stopping Legionella Disease. Before it Starts.

Situation
HydroCorp was called in to help develop a Legionella Disease Prevention Plan for a large Veteran’s Administration healthcare facility, in accordance with VHA Directive 1061. The VA campus is composed of thirteen buildings including a 7-story hospital, Community Living Center, and multiple residential buildings for housing veterans. A HydroCorp team was dispatched to identify any risks the building water systems might pose to patients and residents.

Discovery
The team encountered a spectrum of system deficiencies, leading to conditions that can encourage the growth and spread of legionella bacteria, including:

  • Softened, dedicated non-potable/process water supply in the Main Hospital, supplying medical equipment and building humidification systems, which also supplied cafeteria/kitchen operations and other domestic uses.
  • Domestic hot water temperatures that were consistently well below the required range, such as in the main hospital emergency department.
  • Components in the domestic hot water piping system that malfunctioned near the hot water source – such as a master mixing valve – causing domestic hot water to remain at temperatures conducive to legionella growth throughout the entire facility.
  • Nearly 300 piping dead legs, within both potable cold and domestic hot water piping systems.
  • Numerous terminal-end/low-water-turnover portions of plumbing systems vulnerable to water quality degradation, requiring ongoing legionella sampling to validate future preventive maintenance measures.

Solution
The first step HydroCorp took was to survey and profile the entire domestic hot water and potable cold water piping systems for each building. This enabled the generation of detailed piping schematics that diagrammed all piping, points of use, cross connections and backflow preventers, piping dead legs, and significant water management points such as domestic water heaters, decorative fountains, spa baths, eyewashes, ice machines, etc.

With these schematics, the team was now equipped to effectively characterize the campus’s multiple system deficiencies, with the following actions:

  • Develop Process Flow Diagrams which reflect building water process steps, and identification of critical control points.
  • Perform Legionella Hazard Analysis and Risk Characterization.
  • Develop a Water Management Plan referring to Process Flow Diagram and piping drawings. The Plan established ongoing control measures to reduce the risk of exposure to legionella bacteria.
  • Establish a “dead leg piping” identification, prioritization, and action plan to provide for the elimination of the existing dead leg piping.
  • Perform temperature and chlorine analysis throughout potable cold and domestic hot water piping systems to characterize water quality throughout entire systems.
  • Identify locations where water quality monitoring equipment may be installed.
  • Propose specific recommendations for system corrections of all critical water management points to include ice machines, eye washes, backflow preventers, immersion baths, decorative fountains, domestic hot water makeup units, etc.

Conclusion
Last year, the Centers for Disease Control acknowledged an alarming increase in legionella-related disease outbreaks in the U.S., with more than half originating in hospitals or healthcare facilities. And while it may be ironic, it is not surprising: the overwhelming complexity of a typical healthcare facility water system makes it an ideal breeding ground for this opportunistic disease. With hospital patients already vulnerable, and with a fatality rate of 28%, this growing threat needs a fast and forceful response. And the only way to ensure the success of a legionella prevention plan is with a comprehensive, up-to-the-minute record of the entire building water system, with all potential risks characterized, and corrective actions identified. This VA facility got that, and more, from HydroCorp.