Rimbey’s leaky lagoon letting in groundwater

Rimbey’s northeast sewage lagoon has underground water leaking through its fifth cell due to pressure.

Rimbey’s northeast sewage lagoon has underground water leaking through its fifth cell due to pressure. But since the cell is still under warranty it won’t cost the town to have it repaired.

The earliest start date for the repair works of the clay liner in cell 5 of Rimbey’s northeast sewage lagoon is Sept. 10.

According to CAO Tony Goode, the new lagoon, finished in 2009, was built over an artesian spring. Goode described the spring as being similar to a volcano. “Basically it’s a high water table.”

ISL engineer Robert Perrault further explained the lagoon was built over an area where water breaks off the surface. However, an older lagoon system was in the same location in the mid-1960s and it was built before water started coming to the surface.

The water has compromised the berm under the lining of the cell, which was prepared under warranty.

The town has had ISL Engineering and Tagish Engineering work together to review remediation plans.

Clay from the Bergham property, which the town owns, will be used in the new plans. “We believe adequate, suitable clay is there to rebuild the berm,” said Goode

However, if this doesn’t rectify the situation the town currently has no plans for the situation in the future. Perrault says a backup plan will be developed if that bridge needs to be crossed.

Back when the lagoon was constructed the town had to approve the plans. This was before Goode was involved in the project and he isn’t aware of who would have approved the lagoon.

When the new system was constructed, thicker than normal clay liners were developed. “What we have built there is a high-quality clay lined cell,” said Perrault.

Contractors built a hole to keep the ground water low. According to Perrault the lining in the northwest corner of cell 5 wasn’t built properly.

“Will it leak again? Probably not. Is that a 100 per cent guarantee? No,” said Perrault.

Before the new lagoon system was built it was recommended that a lift station be built on the left side of the highway to move wastewater back to the south lagoon. But the station was never built.

There is also a drainage ditch connected to the lagoon running east and south of town that needs to be refurbished by Tagish. This will cost $600,000.

Because surface water infiltrates the ditch, council is looking for support from the county to help clean the ditch. Goode has already contacted Ponoka County CAO Charlie Cutforth regarding this.

Once remediation work begins, Goode believes the project will take a couple of weeks.