Other Water Systems

In addition to drinking and recreational water systems, water has many other uses, including agriculture, industry, decoration, and healthcare. Each of these uses provides unique opportunities for exposure to unsafe water.


  • Description – Agricultural water is used to grow fresh produce and sustain livestock. Examples of water use in agriculture include irrigation, pesticide and fertilizer applications, crop cooling, frost control, and hydrating livestock. Agricultural water comes from a variety of sources, including surface water, ground water from wells, rainwater, and municipal water systems.  Contaminated water can affect the quality of crops, causing illness in employees and workers who handle these affected food crops or in people who consume these crops. For example, irrigating fresh produce with contaminated water can contaminate ready-to-eat food products, which can lead to illness when consumed.
  • Detection – detecting illness related to food consumption (e.g., fresh produce)
  • Investigation – product traceback leads to farms with contaminated water. Environmental investigation detects the contamination on the farm.
  • Control – Common control solutions include treatment or excluding the use of surface water. Other sources of infection, like wildlife, can be controlled or monitored to prevent future outbreaks. Use of non-contaminated water for growing and processing food can also be used as a control measure.

Outbreak Example: Legionella pneumophila, Florida 2014

Three residents of a federal long-term care facility were diagnosed with legionellosis over a 2-month period; all cases were in one of eight living units. Environmental water sample analysis conducted by the facility from multiple locations including sink, ice machine, shower, fountain, and refrigerator water tested positive for Legionella pneumophila (0.1-2.6 cfus/mL; median 1.4 cfus/mL). Chlorine levels ranged from 0.0 to 0.1 (median=0.01 ppm); hot water temperatures ranged from 105-140°F (median=128°F); cold water temperatures ranged from 65-91°F (median=86°F) during the sampling time frame. The investigation determined that automatic biocide sensing equipment malfunctioned in conjunction with stagnant water conditions that existed in dead legs prior to occupancy likely were factors contributing to the outbreak. Following remediation, the premise plumbing system was continually monitored and point of use filters along with other short-term measures were utilized until the water system was cleared of Legionella. The facility operators continued to develop, improve and implement their water management program.

Industrial Uses of Water

  • Description – Manufacturing and other industries use water during the production process, either for creating products or for cooling the equipment. Notably, large amounts of water are used to produce food, beverages, paper, and chemicals. Heavy metals, solvents, and other accumulated wastes from this industrial production can contaminate local water sources and can be hazardous to human health. Poor water quality can also affect employees/workers. For example, workers may be exposed to various chemicals or Legionella through mists or water used for cooling industrial equipment.
  • Detection – Detection of cases in industrial settings can vary greatly depending on the contaminant. Collection of large-volume water samples might be required to identify pathogens that require special protocols for their recovery.
  • Investigation – At the beginning of an outbreak it’s important to identify as many confirmed cases as possible to help find the source of the outbreak. This can be done through mass mailings, press conferences, the Internet, and other types of public outreach.
  • Control – Due to the wide variety of contaminants, control of industrial waterborne outbreaks will vary greatly by etiology. More information can be found at: https://www.cdc.gov/healthywater/emergency/index.html