3/28/2014 2:34:00 PM CF trying to resolve leak at new library
by Ken Haggerty
For the second year in a row, melting snow has led to a leak at the Cannon Falls Library that opened in February of 2013.
Justin Padgett, library director, said they noticed leaking along the base of the interior southern facing (Mill Street) wall on March 10, the same area where leaking was noticed last year when snow began to melt. About 160 gallons were pumped out of the soaked carpeted area. No damage to books, computers or furniture was observed, but the area was roped off.
Some changes were made last summer that were expected to resolve the issue, including paving over the soil area left right up against the southern side of the building and a concrete pad to direct water draining from the roof into a drain, but the leaking returned.
Bossardt Corp., the company hired by the city to manage the construction of the library, was called in on March 10 and they had American Engineering Testing (AET), a forensic engineering investigation company, look into the leak.
John Amundson of AET said the snow on the roof is melting and running off through scuppers to the east side of the building, which is in the shade most of the day. He said the water is not going down a drain there or into the ground, but running down and around the southeast corner of the building and down the sidewalk adjacent to the building. He said there is evidence of wet spots on the exterior block at a part of the building that bumps out along that sidewalk,
After making small test cuts in the sheetrock at the base of the interior wall, Amundson said they found the six inch wide, one and a half inch wide steel stud sill track had water standing in the sill, overflowing at some spots. They also discovered some wet sheetrock and wet insulation, but did not see evidence of water dripping down the wall from above.
He said he does not believe the leak is coming in from the roof, but is coming up from the foundation. Amundson said he suspects the melting water is coming down the sidewalk on the outside, getting underneath the sidewalk slab, and, due to the frost in the ground, is not draining away, He said instead of draining, the water is building up in what he called a bathtub effect, and then leaking into the building.
AET was going to take out a couple of the sidewalk panels at the area where they think the leak is coming in to confirm their suspicions. Bossardt said they would also inspect the tiling near the foundation on the east and southside to make sure that it is not plugged with sediment.
A revisiting of the water-proofing in the area of the leak will be done.
Morris Mattson asked a Bossardt representative who who will pay for the work. The Bossardt rep said once the investigation can determine the responsibility and cause of the issue, they can assign cost. He said he didn't think the city will be paying for this work.
Mattson said he had met with the Bossardt representative and a cement contractor last summer when work was being planned to try and resolve the 2013 leaking. Mattson said the contractor advised Bossardt how coarse the soil is there and how important it was to get the water away from the building. Mattson said he doesn't think Bossardt did a good job and that the repeated leaking is their fault.
The Bossardt representative noted it was never their plan to have the sidewalk paved up to the building; he said that work was city requested.
Bossardt said the bottom two feet of drywall may need to be cut out and replaced along with any insulation and carpet as necessary to prevent mold damage.