Reviewed Date: 10/02/2023
So what does the fire department do: let the house burn down, or risk contaminating the water system? Either way, it is a matter of public health.
These are very good questions and should be decided before responding to a fire within a community. A coordinated effort between the fire department and water utility is essential in protecting public health in these situations. In many cases, this cooperation has not always existed between the two departments. Issues related to locating or spacing fire hydrants have caused problems in many communities for years. One problem is locating fire hydrants strategic to fire department operations. The fire department’s view is typically not the same as the water utility’s view, especially in allowing for water system flushing. Who has the authority for properly locating fire hydrants? Different jurisdictions have different interpretations of this question. The answer should be that the fire department and water utility work together on these issues to best serve the community. It is important to note that the International Fire Code, which has been adopted by the State Fire Marshal's Office, contains requirements for fire hydrant specifications and spacing.
As required by Rule 0400-45-1-.17(18), the water purveyor must, at least once every five years, notify by certified mail every fire department served by that water system that certain fire hydrants cannot be used for firefighting. Most fire chiefs would say that this is pretty strong language but in the event of an emergency, decisions to use or not to use fire hydrants must be made. Who will assume the liability at the time of a fire where a fire hydrant is available, but the fire department is not allowed to use it? Who will assume the liability if the water system becomes contaminated? Water officials can be held personally liable for allowing the system to become contaminated. Many fire service leaders believe the restriction on using Class C fire hydrants is too unreasonable especially in the event of a possible rescue of a trapped victim or firefighter.
Can people actually get sick from the fire department connecting to a Class C fire hydrant? Will this actually contaminate the water system? According to several recognized articles by the Federal Environmental Protection Agency, there have been documented cases where water contamination occurred due to something that a fire department did or did not do. This way of contamination is quite difficult to pinpoint although a backpressure situation can occur anytime fire apparatus is connected to almost any fire hydrant.
In most cases where waterborne disease outbreaks have occurred, they have resulted in nausea, diarrhea, and cramps, however it is possible in some cases to result in very serious illness and even death. Experts believe that most waterborne disease outbreaks are not recognized, so in truth, there may have been many times more than what is reported. According to the American Water Works Association (AWWA), “Cross-connection contamination can provide an opportunity for large amounts of biological material to enter the distribution system. These events generally result in noticeable change in water quality, including turbidity, increased content of solids, and undesirable tastes and odors.” However, in TDEC's “Tennessee Rural Water Needs Report” it states that only a very small percentage (less than 1%) of the domestic water used in a typical household is for drinking purposes. Therefore, if contamination does occur, there is a small chance that people will be adversely affected.
Fire officials have stated that fire departments seldom connect hard suction hose to fire hydrants, and therefore the possibility of causing a backpressure in a water system is minimal. Most fire departments use a soft vinyl hose to connect the pumper to the fire hydrant rather than the rigid hard rubber hose that was common many years ago. Unlike the hard suction hose, the vinyl hose will collapse as the residual pressure is dropped. Occasionally there could be a need for hard suction hose on a large fire but most fire departments do not carry hard suction hose any more. The exception to this is in rural areas where drafting from ponds or other surface sources is necessary or in tanker shuttle operations where a fire engine is used to draft from a dump tank. Regardless, using hard suction hose is no longer a common operation for most fire departments.
The response to the observation that hard suction hose is seldom used is that it is still possible for the fire department, regardless of the type of suction hose used, to reduce the water pressure in the water mains to a point that results in backsiphonage. The civil engineering definition of backsiphonage is, “The flowing back of used, contaminated, or polluted water from a plumbing fixture or vessel into the pipe which feeds it; caused by reduced pressure in the pipe.” The possibility of backsiphonage and potential contamination negates the argument that fire departments seldom use hard suction hose.