February 4, 2008

CITY OF PRINCE GEORGE

River Road in Prince George has been raised to help prevent the town from flooding. Raising the road to act like a dike was one method the municipality employed to ease the flood risk.

Emergency Response

Roads used in effort to stop river from flooding

City of Prince George turns to roadbuilders to help stop ice-jammed Nechako river from overflowing

Richard Gilbert

staff writer

The construction of a temporary raised roadway has been completed along the Nechako River, as part of the main flood prevention system for the city of Prince George.

The ice began to jam up in the Nechako River after several days of low temperatures at about -20 degrees in early December.

Chunks of the ice jam dislodged, flowing downstream and stacked more than three metres high.

The highest flood levels ever recorded in Prince George were discovered when rising temperatures melted the ice and it overflowed the river banks.

A local state of emergency was declared on Dec. 11, when the ice jam caused the flooding and evacuation of homes and businesses north of the river in the Pulp Mill Road area.

A major ice shift and water surge on Jan. 5 resulted in significant new flooding on Pulp Mill Road and on the south side of the Nechako River along River Road.

A new build up of ice forced water to overflow the Gabion dike system in lower level areas.

In response to the second round of flooding, the construction of a temporary raised roadway by city engineers and contractors began on Jan. 10.

The road provides access to local businesses and functions as the main flood defense system for Prince George.

“We are just finishing some off ramps to a forest products plant. For all intents and purposes that project is complete,” said Kevin Brown, liaison officer for the city of Prince George.

“The temporary raised roadway is the main safety mechanism for downtown Prince George and the CN railway.”

The temporary new raised road was built on River Road and acts as temporary diking.

The road is eight metres high and was raised to .6 metres above the 200 year flood level. The majority of the construction was completed by Jan. 15.

“That piece of raised roadway is the second section constructed along that stretch of River Road. The first section was done several weeks ago, in response to the first bit of flooding on Dec 11,” Brown said.

Flood mitigation work played a critical role in reducing the damage from the second flood on Jan. 5.

When water levels dropped from the first round of flooding in late December, the city began construction activities associated with flood mitigation.

This work included the construction of the portable gabion diking and earth berms, removal and hauling of debris, pumping of flooded areas, engineering consulting and security.

“Experts say the uncertainty with the ice jam could continue into April and May. We just don’t know. So, we are preparing for the worst and hoping to reduce the impact of the ice jam as much as possible,” Brown said.

“We could face further shifts and water surges, which is the reason we are raising River Road. This will protect us in the event of another significant flood event.”

The city of Prince George is built on a flood plain area, which includes a business and industrial area, downtown and residential developments.

The industrial area on River Road has three saw mills, four forest processing plants, warehousing, trucking, petroleum distribution and the CN Yard.

The railway runs from the port of Prince Rupert and passes through Prince George on the way to Edmonton.

This is an important transportation route, because it links the growing container port in Prince Rupert with the U.S. market.

The City of Prince George is working on a plan that would see $4.2 million dollars worth of improvements to River Road.

The plan would include a $2.3 million water main extension and a third section of improvements along the CN line on the east side of the intermodal yard.

The city hopes to receive funding for the project from the Asia – Pacific Gateway programs, since River Road is an integral part of the intermodal operations of CN.

The total cost of the city’s response and recovery program for the ice jam and flood was pegged at more than $3.5 million on Jan 25.

The majority of these costs will be covered by the PEP.

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