Work to resume on Husband Street bridge but at twice the cost due to errant geotechnical report from 2015
Oct. 4—Monday evening, City Council approved a solution to finishing the overdue North Husband Street bridge replacement. The timeline to complete the project is now projected to be 9 months but the cost came in at $1.2 million — $700,000 higher than staff estimated in August.
In the meeting Mayor Will Joyce expressed concern about how the unexpected additional cost for this project was going to impact or delay other transportation projects since they are coming from the same transportation fund.
The additional cost to the bridge project was due to an inaccurate 2015 bedrock depth report from Terracon Geotechnical Services that showed sandstone at a depth of 12.5 feet and boring stopped at 23.6 feet, according to City staff.
After demolition of the bridge, crews from Lopp Construction discovered the bedrock was not at the depth they expected from the geotechnical report.
Terracon was brought back to do a follow up bedrock depth report and encountered shale at a depth of 43 feet and stopped boring at 51.2 feet.
City of Stillwater Deputy Director of Project Management and Construction, Andy Doerflinger, explained the updated design now required 12, 48-inch drilled piers that will range from 29-41 feet long and require additional underground utilities to be managed. These additional needs significantly increased cost of the new bid.
Councilor Kevin Clark asked if the City was going to be compensated for the errant depth report from Terracon. City Attorney Kimberly Carnley said her office is looking into the possibility of recovering damages from Terracon.
Having been the sole bidder, Lopp Construction will resume work on the bridge it started in June and has the potential to receive a $22,500 incentive bonus if work is completed ahead of schedule.
Doerflinger shared his reasoning was to get the bridge done as quick as possible so that residents can again travel on North Husband Street without costly detours.
