City council will consider adding a further $8.5 million to its debt load during Monday night's regular meeting to cover the cost of building the bridge on Willow Cale Road at Haggith Creek bridge and dealing with the sinkhole on Winnipeg Street.
Of the total, $6.8 million is for the bridge project. Previously expected to cost $3.7 million, the bill rose a further $3.1 million after the project on ran into difficulties.
Work on the sinkhole added up to $1.7 million.
Pending council approval, money for both projects would be borrowed over five years. A term for longer than five years is not possible as elector assent would be required and the projects have already been completed.
Debt-servicing costs over those five years add up to $1.47 million for the bridge and $368,364 for the sinkhole and both those totals would be incorporated into the 2020 levy. The $3.7 million first earmarked for the bridge was included in the 2019 levy.
Combined, the cost of borrowing for the two projects will increase the property tax levy for 2020 by 0.95 per cent over the total approved for 2019, according to a report from finance director Kris Dalio.
Previously-approved debt would add a further 0.75 per cent for a total of 1.7 per cent for 2020.
The 2020 levy won't be affected if all 11 projects for which the city will be seeking voter approval to borrow $32.2 million passes the alternative approval process, scheduled to begin April 18.
But for 2021, the levy would rise by 1.41 per cent, of which previously-approved debt would account for 0.87 per cent. For 2022, it would decline by 0.57 per cent due to a 0.89 per cent decline in debt servicing for previously-approved debt.
And in 2023, it is set to rise by 4.01 per cent over the 2019 level, with the $35 million Four Seasons Leisure Pool replacement to account for 2.27 per cent, Fire Hall #1 replacement good for 0.97 per cent and the 11 projects accounting for 1.31 per cent.
But that jump could be tempered.
The city has applied for $10 millon from the B.C.-Canada Infrastructure Program for the Four Seasons Leisure Pool project and on Monday, council will also be asked to give staff permission to apply for a $6.3-million grant from the Clean BC communities fund in the name of increasing the pool's energy efficiency and reduce its greenhouse gas emissions.
Combined, those two would lessen the increase by 1.06 per cent, bringing the amount down to 2.95 per cent for 2023.
In reports to council, engineering and public works general manager Dave Dyer provided summaries of the circumstances that led up to the bills for the Haggith Creek Bridge and the Winnipeg Street sinkhole.
A culvert at Haggith Creek when the Willow Cale Forest Service Road was first built more than 50 years ago, was failing. Because of the depth of the crossing and because the creek is fish bearing, it was decided the culvert should be replaced by a bridge.
Construction began in September 2016 and the bridge opened on March 30, 2017. But by early August 2017, cracks appeared in the new asphalt on the south side of the bridge, indicating unstable ground beneath.
The culprit turned out to be an unstable layer of clay about 20 metres below the surface that was undetected in a geotechnical survey.
The bridge was closed, a culvert was installed in Haggith Creek and covered with five meters of fill to stabilize the ground.
Work on repairing the bridge itself began in early April 2018. Two steel piles were driven into the ground on the south side, a brace structure was built to support the bridge deck, and a new approach span was constructed.
After the work was completed, the north-side bridge abutment was inspected and repaired and the bridge was re-opened in July 2018.
"Because of the urgency of the project to both preserve public safety and the integrity of the bridge structure, as well as to resume access for local industry, the remediation project proceeded as quickly as possible," Dyer said.
After obtaining external legal and engineering advice, Dyer said the city will not be taking any legal action to recover costs from any of the parties involved in the project's design, delivery, or construction.
As for the sinkhole, it first emerged in July 2014. Despite a series of excavations and camera-assisted inspections, a combination of water and over one metre of sediment prevented crews from determining the cause. But a geotextile fabric was used to wrap drain rock in an attempt to impede further movement of sand and gravel underneath the road.
But in October 2014, it opened again when a water main crossing above the storm sewer broke. The main was repaired but once again, in mid-May 2018, the sinkhole re-emerged. No cause was determined and the sinkhole was filled and the road repaved.
Following major rainfall over June 20-21, 2018, a larger, deeper sinkhole formed and a more thorough investigation was carried out. A sheet pile dam and pumps were installed to prevent water flowing back into the excavation from the Hudson's Bay Wetland and the site was dewatered.
It was subsequently found that a 6.5-metre section of the storm pipe, which was about 50 years old, had severely eroded.
"It appeared that the depth of sediment, which was above the eroded section of pipe was keeping the pipe from collapsing," Dyer said. "When the severe storm occurred in June 2018, the sediment would have flushed out some of the sediment, exposing the holes in the pipe and drawing road base material into the storm sewer pipe."
An 8.5-metre section of the pipe was replaced and a concrete chamber was installed to tie together the three sections of pipe that meet in that area.
"The chamber was designed to withstand the high velocity of storm water flowing into the chamber from Carney Street. It also includes a sump and two manholes to allow city utility crews to clean sediment from the storm water system at this location," Dyer said.
The stretch was reopened to traffic on Oct. 26, 2018.
Editor's note: A previous version of this story incorrectly put the final bill for the bridge at $10.5 million. The actual total is $6.8 million with $3.7 million from the original work folded into the same funding source as that for the additional $3.1 million.
