THE WATERFALL WIPE-OUT AT THATCHER BAY, BLAKELY ISLAND (UPDATED)

Blakely Island,
San Juan Archipelago, WA.
Click image to enlarge.
Please see below for one recall update
of the Spencer Lake dam by 
Blakely Islander, L.A. Douglas. 

 

BLAKELY ISLAND DAM BREAKS

DESTROYS MANY LANDMARKS

By Baylis Harris, Owner,

Blakely Island Marina, Blakely Island,

San Juan Archipelago, Washington

January 1965

"Sometime before daylight in the morning of January 30, 1965, the dam and spillway on well-known Spencer Lake on Blakely Island, gave way from the force of heavy overflow of melting snow and several days of unusually heavy rain.

        The situation was reported to Blakely Marina, by the mail boat crew on arrival at about 7:20 a.m. The marina also serves as the Post Office for Blakely Island. When subsequently investigated by islanders, the destruction created is beyond description. The break created a ravine estimated at an increase of ca. 75 feet deeper than the former run-off stream bed. Both Thatcher Bay and Eastsound were muddy for miles in all directions. Hundreds of trees and litter covered an area of approximately 30 square miles, consisting of various trees, the old Thatcher Mill site, which was completely demolished, and fruit trees, and their products floated everywhere throughout the Eastsound area, Peavine, and Obstruction Passes.

The broken dam on Spencer Lake,
Blakely Island, San Juan County, WA.
as noted in the photograph,
 courtesy of L.A. Douglas,
an eyewitness to the scene on this day.
Blakely Island, San Juan Archipelago, WA.
Click the image to enlarge.

Overflow and destruction
from Spencer Lake dam break.
1965
courtesy of eyewitness L.A. Douglas,
Blakely Island, San Juan County, WA.

         Spencer Lake covered an area of approximately 60 acres and was quite deep. Therefore, literally millions of gallons of water were lost along with many of the historical landmarks of the Island.
        As late as 4:00 p.m. in the afternoon, the force of water down this newly created ravine, cut to bare rock, and the cascading waterfall into Thatcher Bay was an awesome sight. Mr. Maurice Rodenberger who was making the early morning ferry trip to Anacortes reported on his arrival and even later by the crew of the Sidney bound ferry via radio.
        From a recreational standpoint, the loss of Spencer Lake will be quite a substantial loss to the Blakely Island Development. Fortunately, the main water supply for domestic use is taken from Horseshoe Lake."

Above text by Baylis Harris. Published by the Friday Harbor Journal, 1965.

THE SPENCER LAKE DAM

By Lance Douglas

(eye-witness testimony below) 

Blakely Island.

Submitted to the 

Saltwater People Historical Society 

May 2023. 

 

"Back around the turn of the 20th century, the people starting the mill at Thatcher Bay built a dam on Spencer Lake to raise it about 15-20 feet to provide more year-round water to operate the mill. The lake as seen nearby the orchard and dam was not there; the lake started out around the corner by the rock cliff. The dam added millions of gallons of water. A 12-inch steel "penstock" was installed down the steep hill to run a generator to power the mill. A penstock is a pipe that delivers water to a hydroelectric generator. The mill folks were certainly entrepreneurs back in the day and they tapped into the penstock with a 2-inch pipe that ran out the length of the pier. Filtered fresh water was then sold to the steamer boats that served the islands from Seattle, Anacortes, and Bellingham. Remnants of the twisted old penstock were still visible at the base of the gorge into the present century. 

        In the winter of 1965, an overflow culvert plugged up and water flowed over the dam and it washed out in a rush of force that could be heard on other islands. All of the mill buildings that were abandoned in the 1940s were destroyed and washed out to sea. The road to Armitage Bay washed out and left the south end of the island isolated for a year or so. A couple of archived photographs show the washed-out area in the mid-1960s and a small access dock to control a culvert valve under the dam during construction.

        After the new earthen dam was built,  the lake filled in one winter from the huge watershed including Horseshoe Lake which flows into Spencer Lake. During the mill operation days, the lakes were referred to as the "upper" and "lower" lakes.

        Around 1980, a brilliant engineer in the north-end community could not stand to see all of the kinetic energy in the form of water flowing out to sea not being harnessed, so he commissioned a generator system to be built. It was located at the bottom of the gorge where the post office once stood and the dam was beefed up and a new 12" PVC penstock was installed down the road to power it. Up into the 21st century, the penstock delivers about one million gallons of water daily to the 50 kW generator but only runs seasonally. The generator system was gifted to Seattle Pacific University who had been gifted many acres of land where they built a marine biology lab on the island with a full-time caretaker."

Below: 

History of the earliest days of Thatcher Mill Company written by 
Nancy McCoy. Article sponsored by Lopez Island Historical Museum; published by the Islands' Weekly, 2000.

Click image to enlarge.
From the archives of the 
Saltwater People Historical Society.