The 100th anniversary of the construction of the Three Mile Falls Diversion Dam will be celebrated Thursday, May 22.
The dam is the main irrigation diversion for the district and a major collection and counting point for adult salmonids returning to the Umatilla River, according to a news release from the West Extension Irrigation District.
Tours of both sides of the dam will be open. The east bank facility handles the returning adults and there appears to be record numbers this year, the district said. The west bank facility handles the juveniles. This is a rare opportunity to have these sites open to the public, the district said.
The dam was the first project of any consequence for Morrison Knudsen, a company founded in 1912, now known as Washington Group International. It won the bid by $200 and made a profit of $14,000 on the $120,000 Reclamation contract.
The crew arrived July 7, 1914, and the dam was dedicated Nov. 24, 1914.
The dam is a concrete multiple arch weir that has a hydraulic height of 23 feet and a crest length of 915 feet.
Concrete was delivered to the dam by hand-pushed carts along an 800-foot-long trestle built along the crest curve.
The city of Hermiston also will open its new recycled water facility, which is under construction, for tours.
The city of Umatilla has arranged for a tour of the old town site where attendees can learn about future plans for the area. At the event site, there will be displays available of the building of the dam and related projects. Vans will be provided for the tours.
The event and tour schedule is:
-- 9 to 11:30 a.m.: East bank Confederated Tribes of the Umatilla Indian Reservation fish handling facility open
-- 10 to 11:30 a.m.: Tours available of Old Town Umatilla Site, city of Hermiston Water Recycling Plant, west bank juvenile handling facility, west bank open for dam tour
-- 11:30 a.m. to 12:30 p.m.: Lunch served by the Hermiston Lions Club
-- 12:30 to 1:15 p.m.: Speakers and commemorative ceremony
-- 1:30-3 p.m.: Tours resume
The centennial event is open to the public. Speakers will be Steven Jarsky from the Bureau of Reclamation, Gary Burke from the confederated tribes, Ed Brookshire from the city of Hermiston and Phil Ward from Oregon Water Resources Department.
Events will be at the fish handling facility at 81018 Umatilla River Road in Umatilla.
Contact the West Extension Irrigation District office for more information at 541-922-3814 or firstname.lastname@example.org.