‘Unforeseen and uncontrollable’

Trunklines project still isn’t finished, but all the money is gone

When it was still just an estimate on paper, the water and wastewater lines stretching across the village under the Millennium Trail were expected to cost $12.2 million. That was 2021. By the time the work was tendered, two years later, the project’s cost had risen to $16.1 million. The scope of work had also widened. In the interim, municipal staff discovered that the rock is hard in Wellington— the sewer line could not be buried deep enough for gravity to carry its flow to the waste treatment plant.

It meant a pumping station was needed. Another $6 million. The cost of the trunkline project had risen to $22 million by January 2024

Today, the estimated cost to complete the trunkline project is $31 million. Quite a bit more than double the original estimate. It may rise further.

When the project commenced at the beginning of 2024, it was expected to be finished within 18 months. Two and a half years later, however, there is no end in sight.

According to a report delivered to Council on Tuesday, the delays and cost overruns were the result of “unforeseen and uncontrollable” events.

Specifically, the contractors found railway steel under the former railway line. Hard boring conditions were encountered under Lane Creek. The contractor found “two significantly different rock conditions than were identified in the geotechnical and hydrogeological investigations”. Further, the contractor was deluged with “significant and unexpected” groundwater infiltration in the trenches.

The original project design anticipated 20 cubic metres of water infiltration per day. At times last year, crews managed more than 3,000 cubic metres per day.

Conflict between construction crews also led to delays and cost overruns. Blasting was stopped as the trunkline crew approached the pumping station team. The pumping station contractor was concerned that explosive rock breaking might impact its work. The resulting standoff between contractors ultimately led to the reassignment of the pipeline work.

Furthermore, crews had to work around an “unlocatable” fibre-optics line running under the Trail and a pre-existing shelter for Millennium Trail users at the top of West Street.

The upshot is that the project requires $5 million more than has been budgeted so far. According to Shire Hall, $26.9 million has been spent to date on the project. They feel that the extra money will see the project to completion, including the rehabilitation of the Trail.

The current target for completion is September.

Stay tuned.