Cost Estimate:

Stage of Development:

  Phases 1 and 2 of this four phase project are complete     at a cost of $2 million.
  Phase 3 construction is complete. This phase installed a     new 24-inch transmission waterline to replace the     troublesome waterline that ran along streets in the     Downtown area such as Market and Center Streets.
  Phase IV should wrap up by May 2004. This is the last     phase of the project and replaced the waterline north of     Stone Drive to the Fairview Avenue water storage tank.

  In April 2001, Department of Public Works staff provided a presentation to the Board of Mayor and Alderman (BMA) highlighting the findings of a six month engineering study commissioned to investigate the causes of the water breaks in the City's largest water main.

 After ruling out internal spikes in pressure (also known as waterhammers), pipe corrosion, differential settlement, surface loading, cathodic exposure, thermal expansion/contraction, and numerous other prospective causes of pipe failure, the engineering study discovered that the sulfur based joint sealant that was standard for pipes built in the 1930's - 40's was reacting with water in the soils and with the cast iron pipe which created expansion pressure in the joints. When this "joint swelling" pressure exceeded the threshold of the cast iron pipes to flex, it caused the pipe to blow-apart as the cast iron snapped under extreme joint pressures.

 The conclusions of the April study recommended complete pipe replacement using state-of-the-art ductile iron pipes and rubber gasket joints. Cast iron has been obsolete for over 40 years in the water industry and because the problematic joint sealant was used at every joint (approximately one joint every 18', over 480 joints total in the water main) it is impractical to dig out and replace each joint.

 As a result, the study recommended full pipe replacement at an estimated total cost of $6.3 million over 6 years in a 4 phase construction project. In addition the study recommended relocating the water main out of the core business district to minimize construction impacts on traffic, business and residences.

• Proceed with replacement of the downtown waterline as quickly as possible as outlined in the engineering study.

To view a Quicktime movie of a section of waterline installation, click here. Please be patient as this is a very large file (33.6 MB).