When the Town of Middlebury, Vt., faced a significant reduction in capacity of a critical sewer force main, it gambled – and won – on the use of a novel cleaning technology. Ice pigging restored original pipe capacity, increased system efficiency and reduced the potential for combined sewer overflows.Middlebury is a town of fewer than 9,000 people, located about 50 miles southwest of the state capital Montpelier. Its sewer system is relatively young; most of it was constructed in 1960.Gravity sewer pipes are made of a variety of materials, including clay and PVC between 6 and 24 inches in diameter.
