On Dec. 23, 1918, extensive property damage resulted from a flood in Boxley Canyon near Cedar Falls reservoir, constructed by the city of Seattle, Wash., for municipal water supply and power purposes. The North Bend Lumber Company sued the city for damages shortly after the disaster and a series of suits have dragged on through the intervening years to a decision adverse to the city recently handed down by the State Supreme Court in Washington, sustaining a verdict of $336,945.80 rendered by a jury in the Pierce County Court in 1927.
The Cedar River dam is a concrete structure of gravity section, arched in plan, approximately 200 ft. high in the maximum section and having a crest length of about 1,000 ft. (Engineering Record, April 10, 1915, p. 471.) It is situated in King County about 40 miles southeast of Seattle on Cedar River, a tributary of Snoqualmie River, near North Bend, Wash., and about 1 mile west of the point where the river leaves Cedar Lake. The dam had not been completed, but storage in the reservoir had begun and the water level had been raised materially when the flood occurred in Boxley Creek.
Boxley Creek, also a tributary of the Snoqualmie River, drains a small watershed to the north of the lower portion of the Cedar River basin. The summit between the Cedar and the Boxley watersheds is a glacial bench, approximately a mile wide. A washout and slide on the Boxley basin side of this summit marked the first visible evidence of the flood that swept down the stream below.
After the flood a suit was filed by the North Bend Lumber Company, claiming $360,000 damages on the ground that the flood resulted from water impounded in the reservoir behind the Cedar River dam; that this water, by seepage and percolation, passed through approximately 1 mile of glacial moraine on the right bank of the reservoir and broke out at the head of Boxley Creek. The lumber company further contended that the rising of water in Rattlesnake Lake situated below and to the west of Cedar River was evidence that the impounded water behind the dam was the source of trouble and was responsible for the damage caused to the lumber property.
The city contended, on the other hand, that the water impounded behind the dam was in nowise responsible for the occurrence; that Rattlesnake Lake had a history of rapid rises as far back as 1852; that the breaking out of the water causing the damage occurred in the north lateral moraine of the Cedar River glacier; that the north lateral moraine was connected directly with Cedar Lake, more than a mile from the Cedar River dam; that the lake in times past, before the erection of Cedar River dam, had risen to a considerably higher elevation than at the time of the alleged damages, and that there was an impervious stratum separating the north lateral moraine from the impounded waters of the pool.
In the first decision the finding was in favor of the city, but in two subsequent cases of the Chicago, Milwaukee and St. Paul Railway against the city involving the same state of facts the juries failed to agree. The county court decision against the city was rendered in Pierce County, March 14, 1927, after a change of venue from King County, in which Seattle is situated, and was sustained by the State Supreme Court as noted. The trial judge interpreted for the jury that waters impounded by the masonry dam included all the waters of Cedar Lake whenever the waters of the impounding basin behind the dam had risen to the height of the lake outlet.
By way of reference to the court procedure the following citations are given: