While the weather may not be much of an indication, according to the calendar, spring is officially here. As we shift our focus from frozen pipes to watering lawns, let’s take a look at the numbers from one of the harshest winters our crews have had to contend with in the last 10 years.
Every fall, Cleveland Water begins preparations for the winter season. This includes preparing for an anticipated increase in main breaks that is common during cold weather. Each winter brings a different challenge as exact weather events can never be anticipated. This winter, a two-week long stretch of single-digit temperatures beginning mid-December and extending into January created conditions that caused water mains to break at a high rate. On January 3rd alone, we experienced 27 main breaks. In comparison, for a normal winter, we average between 7 and 10 breaks daily.
As a result of the long stretch of low temperatures, Cleveland Water experienced the highest number of water main breaks of any month in the past 10 years, with a total of 517 breaks in the month of January. The previous record was set in February of 2007 with 390 water main breaks.
Our dispatchers and pipe repair crews worked around the clock to quickly respond to the record number of main breaks. Main break repairs are scheduled according to the priority of the break, which is based on factors such as its location and severity. But during the winter, every break becomes important to address as quickly as possible since the leaking water can freeze, creating hazardous conditions.
The recent implementation of Cityworks, Cleveland Water’s data-driven work management system, was also key in helping to quickly resolve the high number of breaks. The Cityworks program is able to monitor the status of each main break in real time. It uses GIS to map each break location and logs descriptions and photos from the field to monitor each job from investigation to restoration. This detailed information kept staff constantly informed of how many breaks there were, where they were located, and how quickly they were being investigated and repaired.
The data collected also confirmed that breaks occurred more frequently in older areas of the system. This is to be expected in older infrastructure systems like Cleveland’s and the driver behind why $26 million in capital funding is being spent annually to renew and replace mains in these and other areas.
With the winter weather (mostly) over, the data collected will also be used to make adjustments for the next winter season. The likely root cause for the increase in breaks is deeper-than-usual frost line caused by the long stretch of freezing temperatures. When this happens, the frozen ground increases the downward ground force onto the water mains to around 400 pounds or more per foot, more than double the norm. The deeper the frost line, the more pressure on the water mains and the more likely the pipe is to fracture under the pressure, particularly if it’s an older cast iron pipe. Knowing this, next winter we’ll be utilizing in-ground thermometers that monitor frost depth and duration in order to increase our ability to detect deep ground freezes earlier.