There may be a solution to Shelburne's population-limiting sewage treatment allocation disclosed by R.J. Burnside & Associates earlier this month, but the solution may take some time.

The issue was discussed by town council in several closed-door sessions and in a report produced by XCG Consultants Ltd., a Kitchener based environmental consulting firm, that was released on Tuesday.

Mayor Ed Crewson said the in camera sessions were necessary because it is still a legal matter.

The report, dated April 13, states the waste water treatment plant (WWTP) may have the potential to be re-rated to treat higher average day flows than the current rated capacity.

"I am relieved there is a potential solution," said Mayor Crewson, "although the process could take up to nine months."

Earlier this month, council learned that the town's planned growth may be severely limited when Burnside said it made a arithmetic error in a report on Shelburne's sewage treatment capacity.

According to a Town press release dated April 2, "prior to January 29, R. J. Burnside had set the available capacity for allocation to the Shelburne North and Northridge Estates development at 570 units."

Shelburne council used the information from Burnside and in accordance with the Official Plan approved the draft plan of subdivision for Northridge Estates, allocating 285 units - half the available capacity - with the other half going to Shelburne North.

On January 31, Burnside sent correspondence saying the capacity was 140 units lower, thanks to a higherthan normal rainfall in 2006 and an arithmetic omission the firm had made in calculating the treatment plant's capacity.

Mr. McGregor confirms that the peer review is complete and Henderson Paddon & Associates Limited of Owen Sound had supported the 250-unit allocation.

"There is no huge difference in the numbers," said Mr. McGregor. "The reports are based on assumptions, so there are always variations, but the two companies support the 250."

Town Council met in an emergency session last Friday and again on Monday to discuss the report.

"If we can be rerated, we would be looking at a 10 to 15 per cent increase," the Mayor said.

Mr. McGregor said XCG had prior knowledge of the facility because it was the engineering firm that produced an optimization study on the treatment plant for Shelburne in 1995.

XCG reported the Shelburne plant has been systematically upgraded and expanded since completion of a class environmental assessment in July 1996, from an original rated average day flow (ADF) capacity of 2,045 m3/d (cubic metres per day), to a rated ADF of 2,971 m3/d."

According to Mr. McGregor, the town's growth is limited by the amount of effluent the receiving stream - a tiny tributary of the Boyne River - can take, and the Town will have to apply for the rerating of the hydraulic capacity of the plant through the Ministry of the Environment. The allocation of sewer capacity has prompted several calls to council members asking why construction is continuing if there is a problem.

Councillor AJ Cavey said the allocation issue "is dealing with future growth only. The houses already under construction are not affected by this. They are previously committed and have the allotments."

Mr. McGregor said a recent overflow at the lagoon "was another separate issue."

The lagoons are used for overflow during times when the treatment plant is working at capacity, typically during an above-normal rainfall and when the snow is melting, to hold the water until the facility can handle it.

Mayor Crewson said there was still work to be done on the sewer allocation issue but "there is some light at the end of the tunnel."