VICTORIA -- After decades of debate and nearly four years of construction, the Capital Region is on the home stretch towards completing its new tertiary sewage treatment plant.

There’s still a lot of work to be done before it’s finished but the construction is now far enough along that trials have begun taking place, using potable water, to see how it runs.

Currently, when you flush your toilet in the CRD (Capital Regional District), your waste passes through a six-millimetre screen before the raw sewage is flushed out into the ocean's currents, one kilometre off of our shoreline.

As of Dec. 31 of this year, that is all going to change.

“We have been working on the project now for almost four years and we’re on track to meet that regulatory deadline for treatment by the end of the year,” said Elizabeth Scott, deputy project director with the CRD’s Core Area Wastewater Treatment Project.

“We’re very pleased to be where we are and excited to be so close to the finish line.”

It has been a massive undertaking, coming in at just over three-quarters of a billion dollars and claiming the title of the largest infrastructure project ever in the CRD.

Once the tertiary treatment plant is completed, your sewage will still pass through two existing pump stations on its way to the new Mcloughlin Point Wastewater Treatment Plant. The two stations are located at Clover Point and Macaulay Point, and have both been expanded, rebuilt and rerouted.

“What we’ve done at these pump stations is upgrade them so that they include screening and de-gritting,” said Scott.

At those pump stations, waste runs through a machine that separates large solids from liquids. That liquid is then pumped through 35-kilometres of piping across the CRD until it reaches the new treatment plant, where it will receive the royal treatment.

It’s a three-stage treatment process beginning with primary treatment.

“That’s a physical process where you separate out the solids,” said Scott. “You basically allow heavier solids to settle out in giant tanks.”

Then, the waste passes on through to the secondary process, which is a biological process. During this step, micro-organisms breakdown some of the dissolved and suspended solids.

Finally, waste will then pass through tertiary treatment, which is when the effluent passes through a five-micro disc filter.

“The cumulative impact of those three stages is that you’ve removed and completely eliminated many pharmaceuticals, compounds of emerging concern and contaminants,” said Scott.

The CRD’s waste system will soon exceed provincial and federal regulations, which only require secondary treatment.

The last step before sewage makes its way to the ocean includes a two-kilometre journey down an outflow pipe. The waste is then sent down to a depth of 60 metres, where the treated water will be discharged into the ocean.