A man from Washington state and a man from Manitoba have pleaded guilty to environmental charges after damaging the shoreline at Madge Lake in Saskatchewan's Duck Mountain Provincial Park, near the province's border with Manitoba.

The charges stem from landscaping work at a cabin belonging to Stanley Riddell, 62, of Sammamish, Wash., according to a Saskatchewan government press release.

Jeffrey Dahl, 34, of Swan River, Man., was the construction contractor.

The clay that was left over from basement excavation was placed between Riddell's property and the shoreline, which damaged natural vegetation, the province said in its news release.

The clay was then used to landscape beyond Riddell's property down to the lake, which resulted in sediment running into the lake.

Both men were charged under Saskatchewan's Environmental Management and Protection Act and pleaded guilty on Oct. 17. Riddell was fined $12,600 and Dahl was fined $9,800.

They have been ordered to return the damaged land to its natural state.