Emergency repairs and replacements exist in every distribution system. With much of our infrastructure being installed in the 1950s, 1960s, and 1970s, assets do age over time and become vulnerable to failure. The emergency repair crew is responsible for all emergency related duties. This includes service line failures, main line failures, replacement of broken fire hydrants, and a variety of other tasks. While we do conduct preventative maintenance, it only reduces the chances of unaccounted for failures within our distribution system, it does not eliminate them. The emergency crew is often working in hazardous conditions that are very dangerous. If you ever see our emergency crew performing a repair or a replacement in the street please be cautious; these situations often require a great deal of heavy equipment that has low visibility. Please restrict your path the sidewalks if walking or a designated detour if driving.
Main Line Repairs
The most costly system repairs that we make are often a result of failed/broken water mains. As pipes age they corrode from both the inside and the outside. When high surface loads, surges in pressure, and soil expansion take place, the reduced structural integrity of the pipe often gives way to these changes in conditions. As emergency crews are dispatched, our staff isolates the affected areas so repairs can begin. Depending on the extent of the damage, we generally have two repair options, replacing sections of pipe, or installing clamps over the areas that broke.
Clamps are generally available for main line breaks under 24 inches in length where the pipe has not completely lost structural integrity. These clamps create a seal around the broken section of the pipe and act as a permanent fix to the broken section of the pipe.
With larger main line failures sections of pipe are often replaced. If sections of pipe are replaced staff uses solid couplings to seal points where the new pipe and old pipe connect. These sleeves are pressure rated and load rated to act as permanent fixes to large scale main repairs. With large main line failures there is often a great deal of excavation and cleanup that is required due to the power and force that water has at such high quantities. The water distribution staff deploys silt retention devices and dechlorination tablets to try to minimize the impact that water breaks have on our local creeks and the wildlife that inhabits them. Our environmental compliance section also works directly with distribution staff to ensure that all precautionary measures are taken to minimize risks to the environment.
Service Line Replacements
Water service lines are the smaller water lines that supply water from the water main to your home or business. The distribution team replaces anywhere from 60 to 250 service lines per year depending on a variety of factors. The most common cause of service line failure is pipe material. During the 1980s and 1990s utilities across the country installed a service lines in a material known as polybutelene, or PB. Polybutelene, while not known at the time of installation, is a defective material with a very short life span. Since the 1990s city staff has been replacing failed PB services and proactively replacing it in our system. for more information on polybutelene please visit http://www.polybutylene.com/poly.html.