There are many essential tasks that require the attention of water department and fire officials, but taking the time to regularly inspect hydrants ensures their functionality, maintains a favorable rating for the fire department and presents an image of preparedness for the community.
D. J. Zeedyk, water systems supervisor for the city of Defiance, Ohio, said opportunities are available for learning how to conduct maintenance properly.
“Most manufacturers will give a three- or four-hour session on tearing a hydrant apart and repairing it, but for the most part, just routine maintenance can be taught in a half hour or so.” He recommends consulting American Water Works Association and National Fire Protection Association guidelines for the inspection and maintenance of hydrants, but he also explained a few of the basic procedures.
Typical inspections include ensuring that each hydrant is free of obstruction and is adequately painted. Hydrants are color coded to indicate the various system conditions, including specific information about the water main, the type of distribution system and the system pressure. An inspection also includes lubricating threads, replacing caps, checking for any leaky gaskets and conducting a flow test to determine both the amount of water available for fighting fires and the general condition of the distribution system.
Planning ahead is important for conducting a flow test. Personnel should review the layout of the distribution system and determine which hydrants will be used to measure flow and which will be used to measure the static and residual pressures. Previous tests can be used as a benchmark for what the flow and pressure should be. Ideally, the tests should be done when system consumption will be normal.
There are several issues to keep in mind when conducting hydrant maintenance. The first concerns the two types of hydrants: wet barrel and dry barrel. Wetbarrel hydrants always have water in them, so they are often used in areas where the temperature does not dip below freezing. Dry-barrel hydrants are designed to automatically drain after each use, so they are more common in areas that experience hard winters. Wet-barrel types can be used in cold areas, it just means that extra maintenance is required, as Zeedyk described.
“We do our hydrants on at least a yearly schedule, but most get attention twice a year. With our type of hydrants we have to pump the water out of each and every one in the fall to prevent freezing. Our soil types do not drain very well, so the non-draining type that we use is perfect in our area.”
Chief John Reese of the North Ridgeville, Ohio, Fire Department described another problem that attends hydrant maintenance.
“The most common complaint we receive when flushing hydrants is that residents experience brown or rusty water in the areas that we are flushing. To prevent those complaints, we advertise on our city website where we will be flushing hydrants and give instructions for residents to run their water until it is clear before using it.” Zeedyk added, “When you get to the point of flowing the water, it is going to disrupt water for several blocks and cause things to flow that normally do not. This is why we do our flowing as close to our semi-annual flushing as possible.”
Reese also spoke about how fluctuating pressure during flow testing creates another concern.
“A lot of the water lines in our city are older and more susceptible to breaking due to sudden surges in pressure. We use pressure-relief procedures and devices to try and keep this to a minimum. The truth is, it’s probably better for a water line to break while we are testing hydrants rather than in the middle of the night when we need the water for a fire.”
A 2009 manual published by the Defiance water department explains this in more detail.
“Opening a hydrant rapidly can cause a negative pressure fluctuation. Therefore, hydrants should be opened slowly until fully opened. Closing the hydrants is more critical, and it must be done very slowly. Closing a hydrant rapidly causes a pressure surge, or water hammer, and this could cause a weakened main to fail. Hydrants should be opened and closed one at a time to minimize the effect on the distribution system.”
Another important reason for regularly maintaining hydrants is that it affects the rating the fire department receives from the Insurance Services Office. Communities with better equipped fire departments benefit from lower premiums, but they also benefit from these evaluations by becoming aware of problems that need to be addressed, allowing them to plan and budget for making improvements in training, equipment and facilities.
The larger the city, the more time it takes to ensure that each one is tested properly. Reese recommended that departments think outside the box to meet this challenge.
“The growth of our city caused an increase in both hydrants to maintain and the number of emergency calls we were experiencing. It was impossible for on-duty personnel to get the job done. Our city council allowed us to team up with the water department to hire summer help, which consists of college students, to perform our hydrant flushing. It has exceeded our expectations and allows us to get more hydrants flushed than we have in years. Sometimes it takes an untraditional approach to get the job done.”
Zeedyk’s advice is summed up in two words: work together. “Hydrants have a lot of important uses, and everyone needs to understand that. It is a good idea to have both [water and fire] departments involved in the process. We do a hydrant class every couple of years for the new firemen and water guys. Then both can understand how each others’ uses are important.”
While hydrant maintenance is not at the forefront of officials’ minds, it is an essential part of ensuring that water will be available wherever and whenever an emergency occurs. Water department and fire officials throughout the country highly recommend using manuals from the AWWA, NFPA and similar organizations that provide excellent standards and detailed instructions for conducting this maintenance safely and efficiently.