Okanagan will use LiDAR to map flood plain

Countless communities across the Okanagan have been hit by flooding over the years, yet very few have actually been mapped as a flood plain.

“There are very few maps for the Okanagan right now. There’s maps that include Mill Creek and Mission Creek. There’s a little bit of Lakeshore over on the west side, and they’re all approximately 25 years old,” Anna Warwick Sears, Okanagan Basin Water Board’s executive director, said.

But that’s about to change.

The Okanagan Basin Water board is receiving nearly $1.5 million to map the flood plain using LiDAR, a special radar flown on an airplane that gives a 3D picture of the landscape below.

“It helps us better predict how the water’s going to flow out of the upper watershed down into the creeks and from there down into our communities,” Sears Warwick said.

“I think the big turning point was the floods in Calgary and it really changed how nationally people were thinking about flood mapping and the importance of being able to predict these things,” she added.

Dams in the upper water shed will be able to use some of the flood plain information for accurate inundation mapping, Shaun Reimer, of the Forests and Lands Ministry, said.

“We’ll have a much better idea of the potential for landsides. It can be used after fires to identify hydrological changes because of the hydrophobic soils that forest fires can create,” he said.

Planes will map from north of Armstrong to the American border, and officials are hoping the knowledge will help them better plan for the future.

“They help understand risks to different kinds of infrastructure like the wastewater treatment plant of the hospital. It helps governments with land use planning, understanding where they need to have different kinds of restrictions for buildings,” Warwick Sears said.

Planes started mapping on Monday, and they’ll be in the air for the next couple of weeks while lake levels are low. They’ll return in July after the snow pack is gone, Warwick Sears said.

The data should be passed on to local governments by the end of the year, she added.