Specimen ID | State | County | Locality | Year |
| Drainage name | Status |
236803
| OR | | Willamette River from RK 5 to Keizer (RK 129)(upper portion - above Oregon City) | 1995 |
17090007
| Middle Willamette | established |
279684
| OR | Clackamas | Willamette River, 10000 m upstream of I-5 bridge to 7500 m downstream of Molalla River State Park. | 1998 |
17090007
| Middle Willamette | established |
165297
| OR | Columbia | Big McNary Lake on Sauvie Island in the Columbia River | 1995 |
17090012
| Lower Willamette | established |
236802
| OR | Multnomah | Willamette River just above Portland (RK 27) | 1988 |
17090012
| Lower Willamette | established |
236799
| OR | Multnomah | Willamette River near Portland | 1982 |
17090012
| Lower Willamette | established |
279680
| OR | Polk | Baskett Slough | 1984 |
17090007
| Middle Willamette | established |