Section of sewer lake line is intact

J. Jacob Edel
Mercer Island Reporter

J. Jacob Edel
Mercer Island Reporter

Cost estimates for the city’s Sewer Lake Line Replacement Project are lower than expected, thanks to a City Councilmember’s hunch that one section of the city’s lakefront sewer pipe was still in good shape. It turns out that the second, northern portion of the project is more likely in good standing than in need of immediate replacement.

While the project was previously planned to replace a 9,000-foot segment of decaying sewer line located in Lake Washington along the Island’s northern and northwestern shores, hired consultants found that about 1,500 feet of sewer pipe was still in good shape. Councilmember Dan Grausz suggested the consultants search for hard facts that the line was damaged last January, and on Monday they reported evidence to the contrary.

“[It’s] a pretty good pipe,” Jack Warburton, a consultant with the firm Brown & Caldwell, said last Monday. “It’s not giving the same deteriorating characteristics of [the other section]. We also found that a Bellevue pipe section analogous to [it] did not break.”

New estimates presented by city maintenance director Glenn Boettcher revealed the cost of rebuilding the sewer line on the shores of Lake Washington and constructing a new pump station would be about $28 million — down by about $8 million if the other section were included. On Monday, the Council authorized staff to spend another $484,000 on the project’s design and put it out for bid in October. So far, the city has spent $2 million on the design, but bids for the project last fall came in substantively higher than expected. The Council rejected both bids, and the city reviewed its proposal and assumptions.

The sewer line needs to be replaced because there have been several breaks and pump station failures in recent years. According to the consultants, the time between failures during recent years has been decreasing, and the city could expect annual failures in coming years if no action happens.

With the cost reduction, Francie Lake of the city’s finance department also said the utility rate would not increase as much as previously planned. The rates are now expected to increase by 10 percent instead of 18.

If the city receives and accepts a competitive bid this fall, the project is on schedule to begin in 2009 and be completed by the end of 2010. Less than 100 homes will be directly affected by the deteriorating pipe.