Although at least some references to an earlier “weir” dam where the Winchester Dam now stands, the dam as we know it, dates from 1890 and the beginnings of the industrial development undertaken by Henry Dumbleton (of Victoria, British Columbia) and Henry M. Dumbleton (of Douglas County, Oregon). The latter served as the former’s attorney and was likely a son, although this is not entirely clear.

Few references are clear on the fact that there were two Henry Dumbletons involved in this action. The original “Plan of the Town of Winchester” indicates that a Henry M. Dumbleton of Douglas County, was serving as the attorney for Henry Dumbleton of British Columbia and is the basis for the above conjecture. This situation is further complicated by occasional references to “Harry” Dumbleton and the “Dumbleton Brothers” although there is no historical basis for the former and the latter makes little sense for two men of the same given name. 

In early May 1890 one or both of these individuals purchased the essentially defunct Winchester townsite, filed a new plat and began to offer building lots based on their intent to dam the North Umpqua and establish an industrial-based community around the supply of ready power. 

In early June, Dumbleton advertised for bids to construct a “mill dam” and Charles A. Briggs, a contractor and sawmill operator from the Coles Valley area, was the successful bidder. Construction was apparently begun immediately. 

The Briggs’ dam was built of log cribbing. There “…were lots of big pine trees above the bench of land along the river and on the bench down next to it. These trees were to be used in making the dam. They were handled with pulleys and blocks.” By August 1890 the work of excavating and building the pier and seat for the great turbine had been completed, a process described as being “…tedious [with] rapid percolation of waters [and] bailing with buckets as the pumps were inadequate.” (Roseburg Review, August 28, 1890)

The Winchester Dam was completed in late October 1890 and its opening was celebrated by a huge festival along the banks of the North Umpqua. 

“Last Sunday was a gala day for Winchester…People came from every direction and by noon the town presented an appearance not unlike a Fourth of July celebration…The dam is a massive structure…timbers consist of huge pine trees not less than four feet in diameter…flooring laid with planks about a half inch apart to prevent swelling…to be filled with sand and natural debris…” (Roseburg Review, November 2, 1890).