Fire hydrants are critical infrastructure that need to function on a moment's notice. Water utilities are usually responsible for keeping hydrants in working order, thus it's crucial for utilities to ensure proper hydrant function using a testing and maintenance program.
With any waterworks infrastructure that will be buried underground for long periods—regularly exceeding 50 years—proper maintenance is essential to ensure assets will perform as needed and fulfill their expected life. However, unlike many devices, a fire hydrant that doesn't work when required can have grave consequences.
The most effective way to keep a fire hydrant in working order is to have a biannual or annual testing and maintenance program. The frequency of the testing and maintenance will depend on the type of fire hydrants in the system (e.g., dry versus wet barrel) and the climate where they are installed. For example, fire hydrants in cold or harsh climates may need more frequent inspections and maintenance.
Here is our list of top 10 best practices for testing and maintaining fire hydrants.
1. Maintain and Inspect Regularly. Inspecting and maintaining hydrants with a regular schedule is critical for a successful program. We recommend using AWWA's Manual of Water Supply Practices M17, Fire Hydrants: Installation, Field Testing, and Maintenance (www.awwa.org/M17), for detailed procedures on inspection and maintenance.
2. Exercise the Fire Hydrant. This will ensure the fire hydrant operates as expected. It's important that when a fire hydrant is operated, the auxiliary valve tied to the hydrant is also exercised.
3. Lubricate Regularly. Fire hydrants are typically greased or oiled. Follow the manufacturer's instructions on lubrication. Without proper lubrication, corrosion can occur, making the hydrant difficult—or, in some cases, impossible—to operate.
4. Flush the Hydrant. It's important to remove any foreign material that may be inside the fire hydrant or lead line. During flushing, we've seen many obscure things appear, such as soda cans, tire inner tubes, bathroom rugs, and chunks of wood. These items can block the fire hydrant main valve, hindering the ability to open or close the hydrant.
5. Check for Standing Water. Inspecting the fire hydrant for standing water is especially important in cold climates. The presence of a high water table or clogged drain holes can cause water to accumulate in the fire hydrant. This accumulated water can freeze and damage the hydrant. An inspection can be done after flushing by holding your hand over the exposed nozzle to feel for small amounts of suction. This signals that the fire hydrant is draining properly. Some fire hydrants located in areas with a higher water table may have plugged drains. These need to be pumped after use.
6. Inspect Traffic Features. During the inspection, double‐check that the breakaway devices aren't damaged. Depending on the fire hydrant's age and type, this feature could be breakaway flanges or breakaway bolts. Some fire hydrant models don't have a breakaway design. It's also important to inspect the fire hydrant's surroundings. Make sure there are no obstructions hiding the fire hydrant, like bushes or debris. Homeowners sometimes landscape around hydrants to hide them from their view or with the best intentions of beautifying the area. However, with no maintenance, such hydrants can easily become difficult for firefighters to find.
7. Ensure Proper Hydrant Height. A fire hydrant that has the incorrect height above the groundline can have serious implications if hit by a vehicle. A hydrant buried too low can cause a hydrant to not break as expected during a collision and make it difficult to remove the nozzle caps. A hydrant buried too high may allow for a vehicle to impact the lower barrel. Improper fire hydrant height can also cause more damage to the vehicle during a collision and damage water piping systems.
8. Inspect for Leaks. A hydrant can be pressurized to inspect for leaks. This is achieved by removing a hydrant cap and operating the hydrant a few turns. Allow the hydrant barrel to fill until a small amount is coming out of the nozzle, letting as much air to escape as possible. Replace the cap and fully open the hydrant. With the hydrant pressurized, inspect all visible joints for leaks. A leaking hydrant can cause many issues, including erosion of the soil in areas with poor drainage, accelerated corrosion, and groundwater contamination.
9. Check Hydrant Outlet Nozzle Caps. Over time, corrosion can make nozzle caps difficult to remove. Remove and clean caps during each inspection. Adding food‐grade lubrication or anti‐seize to the nozzle and cap threads can assist with easier operation in the future.
10. Keep Maintenance Records. It's important for a utility to know which hydrants have been repaired/inspected or need to be repaired/inspected. This is an important part of any maintenance and inspection program, and this step benefits from having more details. It's also important that any issue discovered during an inspection is repaired in a timely fashion. Any fire hydrant deemed inoperable should be black‐bagged or tagged to prevent accidental use, and the hydrant should be replaced or repaired as soon as possible.
Water utilities also need to ensure newly purchased hydrants have the same threads and operating nut size as other hydrants in the area. Firefighters need to be able to quickly access fire hydrants. If their wrenches and hoses don't fit, it can cause a dangerous delay. Hydrants with stainless‐steel components will last longer and are better protected against corrosive or hot soil. Proper thrust blocking and installation of a drain field will also help with a hydrant's performance and longevity.
There are no shortcuts taken when it comes to manufacturing fire hydrants because they have a critical function and need to perform on a moment's notice. The most common cause of failure is the lack of a proactive and preventive maintenance program. Utility crews that have solid maintenance programs will have fewer repairs and more reliable hydrants.
Most manufacturers have a step‐by‐step document that walks operators through fire hydrant maintenance and inspection. Also, as mentioned previously, M17 is an excellent resource. Generally, the mechanics of fire hydrants don't change that much over the years, so once you have a good grasp of the basics, you should be set for a long time.
Patrick Nein is a product manager at Mueller Water Products (www.muellerwaterproducts.com).
Alexander Baily is an application engineer at Mueller Water Products (www.muellerwaterproducts.com).