Article | April 12, 2018

Hydrant Humor: Tales From The Field

Source: Mueller Water Products
Hydrant Humor: Tales From The Field

District Sales Engineer Andy Singer has spent enough time troubleshooting problems in the field that not much surprises him anymore. When it comes to dry barrel fire hydrants, though, he still gets a chuckle out of some of his more outrageous experiences. Here is his educational and entertaining take on the care and maintenance of fire hydrants, and ways to maximize a utility’s return on what potentially can be a 50+-year infrastructure investment.

A Prime Target For Abuse

As one of the few above-ground fixtures in water distribution infrastructure, fire hydrants are some of the more vulnerable elements in the system. “In general, people just assume that water will always be there,” Singer says. “We all take fire hydrants for granted, but hydrants are probably our #1 reason for troubleshooting calls in water distribution infrastructure.”

The list of individuals who operate fire hydrants includes people with a wide range of understanding and experience — from novices to experts:

  • Water distribution utility crews typically perform routine maintenance and repairs. However, not every employee has the same degree of experience with inspecting, flushing, or checking pressure.
     
  • Fire departments operate hydrants to fight fires, partner with utilities for flushing programs, and conduct flow-rate testing for fire suppression purposes. Some firefighters may be unaware of the forces at play and how a fire hydrant functions as part of a water distribution system. This could lead to mistakes such as closing a valve too quickly and possibly causing damage due to water hammer in the system.
     
  • Contractors with bulk water trucks, street cleaners, and even private citizens may also access a public hydrant, oftentimes without the consent or knowledge of the water utility.

“With so many people touching them, inevitably some people are not going to be as knowledgeable and well-trained as you would like,” Singer says. “New employees or volunteers don’t always know where the pitfalls are, and that’s one reason we get so many troubleshooting calls on hydrants.”

Figure 1. Activating the operating nut from fully closed to fully opened ensures complete lubrication of all moving parts. (Source: Mueller Company, LLC)

Debris-Catching Dead Ends

Because hydrants are installed on lateral lines that come out of a water main, they are inherently dead-end piping runs. This makes them magnets for debris that gets into the system during initial installation or as a result of water main repairs. Leaks are typically caused by a piece of debris getting trapped in the main valve. However it happens, the call for assistance is essentially the same: “Hey, my hydrant is leaking.”

One of Singer’s more unusual anecdotes came early in his career, and it involved a pair of blue jeans. “How they got there, I don’t know,” Singer laughs, “but they certainly were mangled around the main valve.” A similar experience came when he found someone’s lunch bag — soda, sandwich, and chips in a convenience store bag — inside a leaking hydrant. “You’ll often find debris — typically sticks and stones — in areas of new construction,” Singer relates. “The lunch bag incident happened in a new development where the landscape was barren. A construction worker probably just put his lunch in the only available shade — inside a stack of pipe that just happened to get installed that morning.”

Figure 2. Open and close valves completely. Partial opening increases the potential for debris to get trapped at the valve seal. (Source: Mueller Company, LLC)

Proper Care And Maintenance Of Fire Hydrants

Whatever the experience, there’s a reason and a cautionary tale behind it. Here are three areas of maintenance that Singer stresses:

  • A Motor Oil Slip Up. One of the most “creative” lubricating solutions Singer has experienced is the use of motor oil — used motor oil at that — in the bonnet of a hydrant. “I thought stories about that from the old-timers were just exaggerations,” he says, “until I saw it with my own eyes and smelled it.” He cautions against that practice for two reasons: 1.) A non-FDA compliant or NSF 61 listed lubricant may compromise the safety of a potable water distribution system. 2.) Even among food-grade lubricants, only the manufacturer-recommended lubricant should be used to protect O-rings, seals, and other components from breakdowns caused by incompatible chemistries.
     
  • Preventive Maintenance. On another aspect of lubrication, Singer explains that the valve on a hydrant should be fully opened and fully closed every time the hydrant is used — whether that is for firefighting, flushing, or testing. Doing so is really a preventive maintenance activity because it forces the oil to recoat all the moving parts in the bonnet again (Figure 1). Another reason for the fully open/fully close rule is that hydrants are not designed to be throttled (operated partly open). Running them that way increases the risk that debris can get stuck between the main valve and seat ring, cut the main valve, and cause a leak (Figure 2).
     
  • Easy Does It. Another eye-opener for Singer was the case of a newly installed hydrant being seized up when it was time to be commissioned. “This was a school construction project where hydrants were installed about a year before construction was complete, so the utility contractor turned off the isolation valves once all hydrants were installed and tested,” Singer explains. “It turns out that a landscaping contractor was using this particular hydrant to fill a tank truck — until the day the isolation valve was turned off. They must have used a breaker bar on the end of a wrench trying to get water from that off-line hydrant, because once we disassembled it, the shaft looked like one of those spiral licorice sticks your kids eat.” An even more common occurrence of forcing things, according to Singer, is the flipside of the coin — overtightening the operating nut with the mentality that “if tight is good, then tighter must be better.” Compression-style fire hydrants are seated by the water pressure exerted on the main valve, not how tight you tighten the operating nut.  Compression-style fire hydrants should be left in the “freewheeling position,” which is accomplished by closing the operating nut until it is “snug,” then backing it off a quarter turn.
     
  • Painting Prep Is Key. “In recent years, many major manufacturers have updated to two-part epoxy coatings vs. alkyd enamels to provide much better outdoor performance,” says Singer. Because those new coatings are so much more durable, utility painting schedules, as well as painting practices, should be updated to take advantage of that long-lasting life.

“Utilities repaint hydrants for a variety of reasons,” Singer explains. “Sometimes they do it to color-code according to flow rate so firefighters can know what to expect when they arrive at a fire scene.” The National Fire Protection Association (NFPA) Standard 291 recommends that bonnets and caps be color-coded to signify the “available flow” of the hydrant in gallons per minute (GPM), calculated at 20 psi residual pressure. That color code is light blue for 1,500 GPM and above, green for 1,000 to 1,499 GPM, orange for 500 to 999 GPM, and red for less than 500 GPM.

Whatever the reason for painting, Singer advises that workers take the extra few minutes to do the necessary prep work of roughing up the surface to ensure that the new paint adheres well, instead of flaking off after a year. Following instructions like those listed in the Mueller white paper, “The Proper Painting of Fire Hydrants for Maintenance and Color Classification” can help.

Dealing With The Unexpected

If Singer could offer only one piece of advice to someone encountering an unusual condition in a fire hydrant, it would be to echo the words of his mentor, who taught him about troubleshooting leaking hydrants: “If things are not going right when you’re troubleshooting, step back and think for a minute. Don’t force things. There’s always an answer to every problem if you think about it for a while.”