Tom Gaglardi was found guilty in Kamloops provincial court on Thursday of two counts of harmful alteration of fish habitat.
Gaglardi is president of the firm Northland Properties, which was convicted on the same charges.
His father Robert, who is chair of the company, was also facing the same charges but found not guilty.
At a trial earlier this year, the court heard the Gaglardi family home — known as "Tom’s Shack," according to several Crown witnesses — was undergoing extensive renovations in 2010.
The charges were laid after Tom Gaglardi and Northland Properties ordered workers to alter the shore of Kamloops Lake while constructing a boat launch. Gaglardi is due back in court on Aug. 21 to set a date for sentencing.
During the trial, former Northland employee Jim Parks said he was ordered to destroy documents and throw a computer hard drive "in the lake" when federal investigators began looking into alleged environmental improprieties at the home.
Gaglardi wrote in his notebook throughout the trial and was repeatedly warned by sheriffs to turn off his cellular phone.
The maximum penalties for harmful alteration of fish habitat are fines of up to $1 million and or six months in jail.
Northland Properties owns the Sandman group of hotels, Denny's restaurants and Moxie's Classic Grill. (Kamloops This Week)
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