The new city water treatment plant is still a construction zone. It's expected to be commissioned in mid-June and does not have a filtration system for arsenic because water will continue to be drawn from the Yellowknife River using a submarine line expected to cost $20 million to replace. - Shane Magee/NNSL photo |
Water line to cost $20 million
Project will replace decades-old underwater pipe drawing drinking water supply from Yellowknife River
Shane Magee
Northern News Services
Monday, June 1, 2015
SOMBA K'E/YELLOWKNIFE
The estimated cost to replace a major piece of water infrastructure has doubled in the last three years, hitting $20 million says the mayor.
The submarine water line that runs under Great Slave Lake was built in the 1960s. It carries drinking water from Pumphouse No. 2 at the Yellowknife River eight kilometres to Pumphouse No. 1 on 48 Street. It will have to be replaced in five years.
In 2012, the replacement cost was pegged at $10 million. The most recent city budget estimated it would cost $15 million, a figure Mayor Mark Heyck said in an e-mail Wednesday was outdated and incorrect. It is now $5 million more and the mayor acknowledged it could increase even more as detailed engineering work is carried out.
"It's changed over time as we've seen with construction inflation (on other infrastructure projects)," Heyck told Yellowknifer.
The city does its detailed budgeting in three year cycles, so the mayor said the next budget cycle will be when council will start addressing finer details of the pipeline such as how to replace it, when exactly to do it and for how much.
Growing cost no surprise for councillors |
The increasing cost was not a surprise for two city councillors.
"Welcome to the wonderful world of municipal infrastructure replacement," said Coun. Cory Vanthuyne. "When we look at high cost infrastructure projects in the city, we've seen huge inflationary costs in just a matter of a few years."
Construction costs in the North and in Canada have been running at a much higher inflationary rate than the standard consumer price index, Vanthuyne said.
"That's a very specialized project. There's only a certain number of contractors that will be able to do that work," he said.
Coun. Bob Brooks said the changing cost is understandable given how how the cost to build anything has increased in recent years.
After he was elected mayor in 2012, Heyck was quoted by Yellowknifer saying that because of the high cost to replace the line, the city needs to plan ahead.
"It's a question of planning for the future in terms of, if we're going to maintain the water source at Yellowknife River then we need to start setting aside money for that work because that's a significant expense," Heyck said at the time.
The city has not set aside money for the project so far. Whether to do so is something council will have to decide, Heyck said.
Council voted to borrow $20 million in 2012, ostensibly to put toward the new $32-million water treatment plant expected to open next month. Because the water treatment plant was considered a "public safety issue" the city was able to bypass a referendum requirement on borrowing, allowing it to borrow the money, plus spend an additional $17 million already set aside for the water treatment plant on other capital projects, such as water and sewer line replacements.
The city plans to lobby the federal government for contributions, said Heyck. The mayor cited the federal government's Build Canada Fund as a possible source of cash for the work. It had sought to have the federal government cover the cost as part of Giant Mine remediation but that was denied.
In the year the work takes place, it could mean not doing any of the corrugated metal pipe replacement work the cities does each year. Much of the city's water infrastructure is old, corrugated pipes that urgently need to be replaced, costing millions.
Yellowknife Bay ruled out |
Based on the condition of the iron pipe that's 16 inches in diametre, the mayor said the city expects it will have to replace the line by 2020. That's when it reaches the end of its useful lifespan, which means it may break or rupture. There are reservoirs that store water, but if the existing pipe fails the city has the capability to draw water from Yellowknife Bay, which the mayor stated is completely safe.
Several years ago the city proposed using Yellowknife Bay as a water source instead of collecting it from the river upstream of Giant Mine. Using the bay would mean millions would not have to be spent replacing the line. The plan was scuttled at the time because of concerns about arsenic contamination.
When that decision was made, the city decided not to go ahead with adding a $3-million filtration system to the new water treatment plant to remove arsenic.
The mayor said in an e-mail there is still space in the treatment plant to add that capability "should our environment change."
However, asked recently whether the city would consider taking water from the bay, the mayor said the previous council ruled that out.
"The plan is to replace the submarine line unless there is some different indication by council," Heyck said.
"In my mind the best way to go is to get it from the river rather than take it from the lake," Brooks said.
Vanthuyne also said he believes the majority of residents will favour replacing the line even if it is the costlier option.