Flushing your utilities can be a lifesaver if approached effectively and in an organized manner. The challenge with many utility managers is the failure to establish any type of flushing program or organized flushing routine.
Flushing can be applied to any number of utilities, each with their own benefit. Flushing should be performed on potable water systems, sanitary sewers, and storm sewers. Efficient use of your workforce through a routine flushing program can save time, money and headaches when managing your water mains, fire hydrants, water valves, sanitary sewers, storm sewers, and manholes.
Flushing sewer lines, storm and sanitary alike, can have significant benefits. Utility managers should be in the habit of routinely running jetting equipment through trouble spots and critical mains of a collection system. Sewers with issues related to pitch, cleaning velocity, offset joints and protruding laterals all pose a risk for blockages and back-ups. Sewer trunklines should also be routinely flushed because they can often be oversized and more inclined to the accumulation of sediment. This accumulation may lead to blockages in the sewer line, back-ups into private laterals and untimely repairs which may require costly excavation measures. Routinely flushing the sewers in your district may eliminate many of these issues before they occur.
Watermains should also be a focal point for routine flushing by all utility owners. Like blood flow through your body, a water distribution system relies on a balanced flow throughout its entire system in order to maintain good system health. Underutilized service areas, oversized mains, and dead ends will limit the flow anticipated through the designed pipe network. As a result, you may experience stagnation, low chlorination levels, and non-compliant samples. Opening and closing valves to redirect flow or the opening of fire hydrants are effective ways to flush a water distribution and fight off the aforementioned problems. This practice also has the ancillary benefit of exercising valves to avoid them from freezing in an open or closed position.
Furthermore, let’s not forget that some regulatory agencies require specific maintenance plans to be in place with respect to flushing of water mains or sewer lines. It is always ideal to demonstrate compliance with any and all regulations prior to any scheduled or unscheduled inspections by these agencies.
Of course, no public agency should forget that it is in the business of public service. As a utility owner, it is your responsibility to provide services in a safe, reliable and cost-effective manner. The act of routine flushing helps achieve exactly that in a low cost, safe and efficient way while extending the life of your infrastructure for your customers. Further, it is a relatively visible act that can garner a great deal of positive attention if coupled with a public service announcement.
In short, you need to flush your utilities before you start experiencing any problems. The flushing schedule should be identified as part of a routine preventative maintenance program assembled by your utility. This plan will be site dependent and rely on several variables such as the age of utilities, past performance, previous repairs, soil conditions, etc. Therefore, each utility should determine their own preventative maintenance flushing schedule based on their own specific needs.
Water utilities may realize that certain fire hydrants along dead ends of the system require weekly or monthly flushing in order to draw flow through the pipes to keep the water biologically and chemically healthy. Some sections of a water distribution system may have no identified issues and may be placed on an annual program in order to exercise the valves and test the fire hydrants. It should be noted that it’s best to perform flushing across your entire water system no less than once per year.
Sewer lines can also be placed on a regular preventative maintenance program. There may be stretches of gravity sewer lines that do not meet minimum slope requirements or that have bellies in the pipe. These sewers may need to be flushed or jetted on a monthly or quarterly basis to clear any sediment. Some storm sewers can quickly accumulate debris, trash and leaves during peak seasons like the spring and fall. These utilities may be placed on a semi-annual schedule. Some sewers may be relatively new construction and have no issues with respect to their performance. In this instance, flushing can be placed on an “as-needed” basis and reduce oversight of this utility to periodic inspections only.
Most importantly, your preventative maintenance plan for flushing should be a living and breathing document. There may be utilities missing from the flushing plan that need to be added if they become problematic. On the other hand, the burden of some utilities will be lessened or eliminated if your entity undertakes utility improvements to those areas. Nonetheless, utility owners should routinely update any preventative maintenance plan including flushing plans.
Unfortunately, preventative measures will not capture 100% of the problems. In the event of a sewer blockage, utility owners should be slow to dig and quick to flush the line. Utilities will often panic in their response and decide to dig open a road at the first sign of a blockage in order to get relief on the system. Dropping a jetter into a sewer to agitate and flush a blockage can often be a faster, and much easier solution to the problem. So, you may still find flushing useful as a reactive maintenance measure even if your goal is to use it to prevent that exact problem.
Flushing your utilities is a worthwhile investment that will ultimately save you money, time and resources. One frozen valve on a water main or fire hydrant that has never been exercised because of a lack of flushing can cost thousands of dollars to replace. The time spent chasing down contractors or fighting with bad valves can be a waste of your limited manpower and equipment. Similarly, a flat sewer that backs up into private laterals and basements because it hasn’t been flushed is a public nightmare with costly repercussions. You can save your utility time, money and embarrassment by devoting a small crew to perform routine flushing as necessary.
It should be obvious by now that a well-constructed, highly detailed and organized flushing routine is a necessity for your water and sewer utilities. The cost of implementing a preventive maintenance flushing program is low while the risk associated with not having a flushing program is high.
Utilities who flush applicable infrastructure will save money on expensive repairs and avoid loss of time issues associated with unexpected utility failures. In effect, these same utilities are capable of more efficiently assigning their workforce to organized tasks rather than shuffling them back and forth to respond to emergency issues related failures within your infrastructure.
This simple preventative maintenance task will result in a more efficient utility that is more effectively serving its users. Elected officials, commissioners or board members will view the efficiency gains, reduced service interruptions and satisfied users in a positive light and that will ultimately benefit the utility, its employees and managers. It is the ideal win-win scenario that utility managers cannot afford to ignore.