By Robert J. Abbott
Before 9/11, typical hydrant locks were “add-ons” designed to block theft of parts or water. Since then the focus of hydrant security has shifted from reducing theft to a more urgent need to protect the purity of the water supply by blocking the malicious introduction of a contaminant by way of a fire hydrant. As a result, the sophistication of available protection devices has increased, and the array of designs has expanded to cover a broader range of protection levels.
Today’s devices fall into one of two groups: active or passive. Active devices block access to the hydrant parts and operating mechanism, whether the goal of a would-be vandal is theft of parts or water, or gaining access to the hydrant in an attempt to introduce a contaminant. Among the active devices are locks or shields that fit over the wrenching surfaces of the operating nut and nozzle caps. Typically, active devices must first be removed or unlocked before the hydrant can be operated, using an access controlled key or special tool.
With time and determination, active devices can potentially be circumvented, and usually without leaving behind any tell-tail sign of tampering. One of the newer active devices is a heavy stainless steel band device that prevents hydrant operation or parts removal, but with the added benefit of providing visual evidence of tampering. This style can also be used to mark out-of-service hydrants.
The need to prevent system contamination has led to the development of passive devices. These are designed to block the introduction or spread of potential contaminants via hydrants to the public main. They include check valves, which may be located in or ahead of the hydrant shoe connection, or inside the upper barrel below the level of the nozzles. Another type seals the nozzle closed until opened by water flow from inside the hydrant. Passive devices allow the hydrant to be operated normally using standard hydrant wrenches, and in most cases also allow normal maintenance procedures, all without having to remove or otherwise circumvent the security device.
A significant advantage of passive devices is that they are typically buried or inside the hydrant out of a potential vandal’s reach. When located in the nozzle, hydrant shoe or connector line, maintenance procedures are the same as for a standard, unprotected hydrant. However, types mounted inside the upper barrel may have to be removed. The hydrant manufacturer should be consulted to determine if adding a check valve inside the hydrant will affect the hydrant warranty.
Security Assessment
Begin by evaluating the risk level for the various hydrant locations in the distribution system. A hydrant on a busy central city street corner might get by with a basic locking device or nothing at all. For a quiet neighborhood a stainless steel band to slow a would be agent and increase chances of discovery might suffice. But an isolated hydrant likely needs a passive device to thwart a truly determined individual counting on time and obscurity for success.
The effect on emergency and maintenance access to hydrants should be considered. Special tools for locks must be purchased, distributed, then controlled, and require periodic training to assure correct use, especially in emergencies. Some might also block normal access to the hydrant’s internal parts, changing maintenance procedures and requiring extra time and equipment for hydrant disassembly.
Construct a matrix with the devices you will consider plotted against the various threat levels for the hydrant’s location in your system. Then rate the effectiveness of each device for each location. This can help narrow the choice of devices and quantify the potential cost. Be sure to consider costs for training and changes to maintenance procedures that might be needed.
Trade Offs
Next consider the trade-offs of using one type of device over another. Perhaps a particular lock’s tool will also work on standard hydrants, potentially reducing tool inventory and reducing what crews need to carry. Seek advice from maintenance crews -- their experience with the various models and ages of hydrants in your system might reveal a pattern of repairs that will be easier to remedy if a passive device that doesn’t block access to the a hydrant’s lower barrel or main valve is used. Or if they report certain parts are frequently vandalized, a device that shields those parts would be appropriate.
Hydrant security is evolving as more technically sophisticated devices and contamination detection systems are developed. But waiting for them doesn’t justify the ultimate trade-off of sticking with the status quo instead of addressing what quite possibly could be a critical hydrant vulnerability in your system. By getting to know your distribution system’s vulnerabilities and taking time to learn about the security options available to address them, you can arrive at a workable plan to protect and assure the purity of water you take great pride in providing to your customers.
WW
About the Author: Robert Abbott is the Director of Corporate Marketing Communication at Mueller Company
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