The Thistle landslide was foreseeable and might have been prevented had a proper drainage system been used, according to a geotechnical engineer's deposition read Monday in 4th District Court.
The deposition was one of many read during Monday's proceedings in a lawsuit filed by Thistle residents against the Denver and Rio Grande Western Railroad. Depositions from three engineers with experience at the Thistle landslide site were read into the record.Fifteen Thistle property owners are seeking $1 million in damages resulting from the 1983 landslide that dammed a river and formed a large lake that eventually flooded their property. They say the D&RGW contributed to the landslide and could have prevented it.
According to the deposition of Delmar E. Yoakum, a geotechnical engineer from Santa Monica, Calif., D&RGW should have known the slide was imminent from past movement at the slide site.
"Obviously the railroad had trouble with it quite often," his deposition read.
Yoakum, who has consulted with railroad companies on landslide sites in the past, said it is not uncommon for railroad lines to cut across the toe of landslides. From his experience, railroad companies usually take preventive measures to keep the landslide from slipping - the most common being to drain water from the head of the slide to relieve pressure, he said.
Earlier, the deposition of a geotechnical engineer hired by D&RGW for consultation on the Thistle landslide site, indicated initial efforts by D&RGW to stop the slide were useless and that they did not realize the magnitude of the landslide.
According to the deposition of David E. Hilts, from the Seattle engineering firm of Shannon & Wilson, railroad crews initially moved material off the toe of the slide to keep the rail lines open. A couple of days later crews began removing material about 300 feet up the slope, the spot Hilts initially thought to be the head of the slide.
It was not until Hilts viewed the slide area from on top of Billies Mountain that he realized the magnitude of the slide. "It was clear to me that we were dealing with something very massive," he said.
According to Hilts' deposition, it was then that D&RGW first mentioned the possibility of tunneling through Billies Mountain. The deposition of former D&RGW divisional engineer Ed Waring indicated that D&RGW was aware of earth moving at the slide site for several years. He said the rail lines at the site had been raised about two feet over a 35-year period because of the slide.
Hilts said in his deposition that when he first evaluated the slide area, D&RGW officials never told him of past movement at the slide site.
Two Thistle landowners, Lloyd and Maurice Jackson, testified that they had seen railroad crews working at the slide site in the past. "One time they were there for a month," Maurice Jackson said.
Upon cross examination, they both stated that they had noticed slippage on top of the slide area while deer hunting during the 1950s.
Several Thistle landowners are expected to testify Tuesday about their property losses after the landslide. The defense is expected to argue its case on Wednesday and Thursday. The case is being heard in 4th District Court under Judge Cullen Y. Christensen.