Lower Colliery Dam: an $8 million project?

On Monday night the Lower Colliery Dam was on the agenda. Important questions were raised by delegations as to why the remediation project is over budget.

The combined cost of the initial engineering studies and the construction costs of the spillway is approximately $8 million so far. The next phase will be the middle dam. Don’t be alarmed if $15 million is the final price for fixing the Colliery dams.

Councillors appeared to be surprised by the $4.5 million construction costs so far. This is $300,000 higher than the original estimate of $4.2 million. The reasons given for the extra costs were a temporary bridge, excavation and engineering monitoring.

Councillor Fuller put forward a motion to have a forensic audit of engineering costs for the Colliery Dams project but no one seconded the motion so it died on the table.

Councillor Kipp: “We put a proposal out for someone to review engineering costs on the dam… no one would touch it.”

Remember way back in July 2015 when these questions were raised about the $3 million spent on engineering studies. Did Nanaimo Council ever get answers?

  • What are the dimensions of the lower dam?
  • Is the concrete strong enough to resist erosion?
  • Will it fail if overtopped?
  • What is the spillway capacity?
  • What are the spillway measurements over a high rainfall season?
  • What is the make up of the concrete and rock buttressing?

Construction of the Lower Colliery Dam Auxiliary Spillway started in September 2015 and is scheduled to be completed in April 2016.

Colliery Dam - spillway concrete pour
Colliery Dam – spillway concrete pour – February 2016

Copcan Civil Ltd. was the successful bidder for a cost plus contract for the construction. Engineering design and supervision of the spillway is being undertaken by Golder Associates. The City retained Herold Engineering to provide structural design, field review and survey services.

Here are the numbers for the project so far (not including the $3 million engineering studies):

Lower Colliery Dam Auxiliary Spillway Costs

Design/Construction 2015 Costs (Sept - Dec)Estimated Total Cost
Golder – Geotech Design $549,004 $663,504
Golder – Field Services $175,344 $317,953
Allowance – Seismic Monitoring $50,000
Herold – Structural Design $125,972 $135,000
Herold – Field Services $5,453 $15,878
Herold – Survey
$17,396
$20,000

Copcan - Construction
$1,325,936
$3,127,500
Allowance – Landscaping $190,000
Other $22,472 $25,764
Totals $2,221,576 $4,545,599