The following Timing Units are contained in this District:

Abernethy Cr
Abiqua Cr
Beaver Cr
Butte Cr
Chehalem Cr
Clackamas R
Clackamas R - Oak Grove Fork
Columbia R - Tongue Pt to Bonneville
Columbia R tribs - Tongue Pt to St Helens
Columbia Slough
Eagle Creek (Clackamas)
Fairview - Arata - Salmon Cr
Johnson Cr above Gresham
Johnson Cr below Gresham
Johnson Cr tribs
Kellogg Cr
Milton Cr and Scappoose Cr
Molalla R above Molalla
Molalla R below Molalla
Molalla R tribs above Molalla
Molalla R tribs below Molalla
Multnomah Channel incl. Scapoose Bay
North Fk and Middle Fk Molalla R
Other Willamette R tribs - mouth to falls
Other Willamette R tribs - Falls to Newburg
Other Willamette tribs - Newburg to Yamhill R
Pudding R
Pudding R tribs
Sandy R
Silver Cr
Tanner Cr
Tryon Cr
Tualatin R above Scoggins Cr
Tualatin R below Scoggins Cr
Tualatin R tribs
Willamette R - Falls to Newburg
Willamette R mouth to falls
Willamette River - Newburg to Yamhill R
Yamhill R