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Marilyn Koski Missing Person Case

Last seen in Portland, Oregon on Jan 01, 1989

Victim Details

Created

Jan 16, 2012

Case Added

Jul 17, 2023

Firstname

Marilyn

Lastname

Koski

Current Age

Age At Disappearance

Height

62 inches

Height To

64 inches

Weight

130 lbs

Weight To

140 lbs

Ethnicity

White / Caucasian

Gender

Female

Last Seen

Jan 01, 1989

City

Portland

State

Oregon

County

Multnomah County

Tribal Land

Agency ID

11218

Agency Name

Multnomah County Sheriff's Office

Agency City

Portland

Agency State

Oregon

Agency County

Multnomah County

Agency Zip Code

97214

Agency Contact

Keith Krafve

Contact Job Title

Detective Sgt.

Agency Address

501 Southeast Hawthorne Boulevard, Suite 350, Oregon

Agency Phone

5039884300

Agency Jurisdiction

County

Agency Type

Law Enforcement

Agency Website

https://www.mcso.us/site/

Agency Case #

89.24

Primary Agency

Multnomah County Sheriff's Office

Hair Color

Blond/Strawberry

Left Eye Color

Blue

Right Eye Color

Blue

Last Updated

08/07/2026

Area Last Seen:

Case Description

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The start of a new year brought a somber mystery to Portland, Oregon, in 1989 with the disappearance of 35-year-old Marilyn Sue Koski. In the early hours of January 1st, Marilyn, a resident of a houseboat on the Willamette River, vanished. She was a woman with a notable educational background, holding degrees from both Brigham Young University and Oregon State University, and had previously dedicated her time to teaching physical education and health. Concern for her well-being grew after two no ...

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Last Seen: Jan 01, 1989

Links to Additional Sources (6)

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Missing Person / NamUs #MP13616

Marilyn Sue Koski - The Charley Project

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Marilyn Koski Missing Person Case

Last seen in Portland, Oregon on Jan 01, 1989

Victim Details

Case Description

Continue reading the complete case summary

Links to Additional Sources (6)

Unlock 4 additional sources

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Forum Posts (3)

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