Water Line Replacement Projects
Client—City of Kelso, Washington
The City hired Gibbs & Olson to provide surveying, design, bidding, and construction phase engineering services for water main upgrades at various locations throughout the City. The water line replacement projects were identified in the City’s capital improvement plan and their current water system plan. The aging water lines leaked, required frequent repair, and were the highest contributor to the City’s unaccounted for water loss. Several of the water lines were also undersized and did not provide adequate fire flow capacity. The upgrades consisted of 14,500 feet of 4 to 16 inch ductile iron water distribution piping including associated valves, service meters, and fire hydrants. Most of the work involved complete water piping replacement with a portion requiring new pipeline alignment. During design, Gibbs & Olson worked closely with the City to identify and locate existing utilities. To provide some funding flexibility, these projects were bid in three separate contracts and included different bid schedules and additive alternates. The additive alternates provided the City an opportunity to evaluate the bids and determine the maximum amount of work that could be completed based on the bids received. The first portion of the work included replacement of 1,800 feet of piping and street reconstruction, and was constructed during the summer of 2010. The second portion of the work included replacement of 8,300 feet of piping and street resurfacing and was constructed during the summer of 2011. The remaining upgrades were completed in February 2012 and Gibbs & Olson worked closely with the City’s water treatment plant operators, the contractor and other city staff to reduce impacts to existing customers including a major commercial water user. This portion of the work included replacement of 4,300 feet of piping and 1,500 feet of street reconstruction. The water line upgrades required extensive traffic control and multiple water line shutdowns to make connections. To prepare for construction of the work, in the summer of 2011 Gibbs & Olson developed a shutdown and connection plan that addressed these challenges. The total construction cost for all of the work was $1.95 million.