No matter how experienced your crew is, circumstances can make water main repairs a bigger challenge than you can ever anticipate. Trouble sometimes comes with weather conditions that complicate other problems as it did for a city in Michigan one blustery winter day.
An experienced municipal crew knew they had a ruptured main and they had successfully isolated the problematic section; a 16-inch water main had split, and it was leaking significantly. This was not an unusual situation - the Wyoming, Mich., water repair crew had seen it before and knew what to do, but adverse circumstances were beginning to prolong the repair.
The main contributor to the problem: a stretch of old pipe with old valves. The nearest up-stream valve was broken "open" coming off of a 36-inch transmission main. The crew tried everything to resolve the problem, and after spending 16 hours exhausting all possibilities, the city authorities decided to contact Advanced Valve Technologies Services and order an EZ-2™ insertion valve installation to shut off the broken main.
At 5:30 a.m. EST, AVT was alerted that the city of Wyoming was having trouble fixing a main break because of a broken valve and might need to install an insertion valve. While the city was reviewing its options, the local Michigan-based AVT rep visited the site to help evaluate conditions. At 9 a.m., the city confirmed the request for AVT to assemble a crew and the necessary components and equipment to do the installation. In the interim, Wyoming's water crew continued preparations for the installation of the valve. At 4:30 p.m., AVT arrived on site finding that the municipality had excavated the hole for the valve install and notified the necessary utilities for staking.
The compact valve profile allowed for a smaller excavation than other valve systems and, because costly restraint operations were not required, only one excavation was needed. The EZ-2 design eliminates special restraint operations and avoids the time delays as well as costs of concrete work, forms, and the coordinating of additional services. In consultation with AVT, the Wyoming municipal crew had selected the best new valve location and had prepared the site for the install.
Two special conditions made the project more difficult than standard installs: 1) the new ductile iron valve fittings had to be machined in the field to meet the requirements of the age of the cast iron main; and 2) the weather turned bad with wet and blustery winds and temperatures that dropped to 22°F that felt like 17°F. The irregular dimensions of the old ductile iron pipeline meant that some alterations to the new valve fittings needed to be addressed and confirmed on location and under poor conditions. The extra work required about 1 1/2 hours to complete followed by a 4-hour install - normal for larger EZ-2 valves. (EZ-2 valves up to 12 inches generally install in one hour.)
Despite the special circumstances and location challenges, a new 16-inch insertion valve (AWWA spec materials and normal operating performance) was installed by 10 p.m. on the same day the phone call for help was received. The municipal workers were able to begin work on the main immediately following the valve installation, and repairs were completed quickly.
The combined talents of both the city of Wyoming personnel and the AVT crew meant shut-off was limited to a much smaller service area, and the duration of the shut-off was kept to a minimal time frame. The result was a timely and efficient resolution to a major infrastructure failure. Businesses and homes in the affected area didn't experience a lengthy shut-off of water and the city was able to avoid more costly and time-consuming alternative solutions. The resulting repairs were completed in a matter of hours versus days.
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