Winter Weather & Water Systems: What Utilities Need to Know
The past few weeks, the Southeast has been experiencing a bought of extremely cold weather. With freezing temperatures and snow and ice in the forecast, there have been many conversations about how to prepare. At McGill, we have been thinking about water systems and how they are impacted by the cold weather.
The Greatest Risk
When the temperature drops into freezing and near freezing levels, breaks in the distribution system are the greatest risk to water systems. Breaks are especially damaging on larger distribution lines because a ruptured line could drain the water storage tank, which leads to more problems. Every water system has storage tanks, and these are kept full to be used during peak demand periods when user needs require more water and demand may exceed the instantaneous flow from the treatment plant. When line breaks deplete the water stored in tanks, users can experience issues with low water pressure and flow, which causes frustration for residents and strains municipal water resources staff.
The reason waterlines can break when it is cold is not because water freezes inside the pipe and causes a rupture—they break because when it gets cold, the ground shifts, which can shift (and break) the line. Smaller water service lines or meters may freeze, which requires immediate action from the utility; however, these are normally isolated to a single point of service and do not impact larger portions of the distribution system.
Another temperature-related line issue involves freezing or reduced flows in the chemical feed lines at the water treatment plants. The correct addition of treatment chemical is essential to water treatment, and oftentimes, feed amounts must be changed as the temperature drops. Chemical feed line for alum and caustic, among others, are often more subject to freezing due to the small diameter and low flow characteristics. These lines must be adequately insulated and, in some cases, have heat tracing to reduce the likelihood of freezing.
How to Prepare for Winter Weather
One of the most important things to consider in the winter months is the stock of pipeline materials needed for repairs. It is key that a water department has parts on hand to repair any infrastructure that could break. For example, a department should have repair sleeves for the various types of piping in the distribution system and an inventory of different sizes of pipes to match the ones in the system. This way, if a waterline breaks, the repair process does not start with a stressful search for the correct piece. Having the correct equipment on hand can also help expedite the repair process.
If the department does not have access to pieces of equipment like excavators and front-end loaders, staff members should form relationships with local contractors who can step in and support, if needed.
In North Carolina, there is an organization called NC WaterWARN, which is free for municipalities and utilities to join. This organization connects different utilities and offers mutual aid and support. For example, after a natural disaster, if a utility needed someone to inspect a waterline to try to locate leaks or lost water, they could use this network to find support.
Communication is Key
Finding support goes hand in hand with communication. It is crucial that a water department establish clear channels of communication so that in the event of a water-related emergency, residents feel supported by being informed. There should be a standard system for communication—maybe all updates are posted on a website or Facebook page or maybe there is a text or phone chain. Regardless of the form, it is beneficial to have a plan for how to communicate with residents before a disaster happens.
It is also beneficial to establish internal forms of communication prior to needing them—specifically for water-related needs. Having a pre-determined process for what to do if the worst-case scenario happens should make it easier to respond in a timely, efficient manner. For example, if the department gets a call about low water pressure or an apparent line leak with water going into the road, there should be a process for who answers that call, goes out to investigate, and sets the repair process in motion.
Learn More
Every water system is different, and learning the intricacies of the system can support successful repairs. For the past 42 years, McGill has been helping communities build and maintain strong water systems. To learn more about our water / wastewater team, check out our website. To learn more about repairing water systems in the aftermath of disasters, whether it be a winter storm or a hurricane, contact Keith Webb at keith.webb@mcgillassociates.com.
