2100 Ferry Street SE
Mill Race Park on March 25, 2007
Mill Race Park is located on the bank of Mill Creek where the millrace is separated from the creek by the Waller Dam. This small park is maintained by the Salem Parks Foundation and the Southeast Salem Neighborhood Association.
Mill Creek behind Waller Dam on March 25, 2007
Mill Creek's watershed originally consisted of about 209 miles of streams, but in 1856, the Salem Ditch was constructed to divert flow from the North Santiam River to Mill Creek to provide a constant supply of water power for Salem industry.
Waller Dam on March 25, 2007
In 1864, the Waller Dam was built to divert water from Mill Creek to a millrace, that would allow more industries to have access to water power.
Waller Dam on March 25, 2007
The Waller Dam creates a five-foot change in the water level of Mill Creek.
Waller Dam on March 25, 2007
The dam includes a spill gate that can be opened during times of high-water flow to keep the water level behind the dam low.
Waller Dam Spill Gate & Fish Ladder on March 25, 2007
Next to the spill gate is a fish ladder that allows the fish that call Mill Creek home to get past it.
Waller Dam Spill Gate on March 25, 2007
Mill Race at Mill Race Park on March 25, 2007
The millrace is over one mile in length and passes through the grounds of Willamette University and two downtown parks, before emptying into Pringle Creek to the south.
Mill Race Control Gates on March 25, 2007
The flow of water in the millrace is regulated by the control gates located here.
Map of the area around the Waller Dam
The Salem area is home to a variety of fish species that can be found in Mill Creek. These fish include Sculpin, Speckled Dace, Redside Shiners, and Northern Pikeminnow, as well as three species of salmonid fish: the Chinook Salmon, the Steelhead and the Cutthroat Trout.
The Chinook Salmon (Oncorhynchus tshawytscha) is the least abundant of all the salmon species but is also the largest, sometimes reaching 100 pounds or more. Chinook salmon lay their eggs, or spawn, on gravel bars in the Willamette Rivers and its tributaries between August and October. The female digs a redd, or nest, in the gravel and lays about 5.000 eggs, which are immediately fertilized by the male. Within a few days of spawning, the adults die. In two to four months, the eggs hatch, and the juvenile fish spend several months near the place they were born, feeding and growing larger until the spring, when they migrate down the Willamette and Columbia Rivers to the Pacific Ocean. The fish live in the ocean for three to five years, migrating as far north as the Bering Sea before returning to where they were born to spawn, completing the cycle.
Most Chinook Salmon in Mill Creek return from the ocean in the spring. These Spring Chinook are native to the area. The entire Upper Willamette River system had no native Fall Chinook. Fall Chinook fingerlings from state hatcheries were first planted in Mill Creek by the Oregon Department of Fish and Wildlife in 1968. The first adult Fall Chinook returned to Mill Creek to spawn in September and October of 1970. The early runs averaged 6,000 fish annually.
Sign about Fall Chinook at the Waller Dam on March 25, 2007
A sign was posted on the fence on the opposite side of Mill Creek from Mill Race Park by the Oregon Department of Fish & Wildlife explaining the program when Fall Chinook were still being planted in Mill Creek and it remains there (as of 2007), largely forgotten. Fall Chinook are no longer stocked in Mill Creek, but a few Fall Chinook, descendants of those planted fingerlings, occasionally return to spawn.
| Spring Chinook (Native) | Fall Chinook (Introduced) | |
| Juveniles | Stay in the Willamette and its tributaries for several months. | Stay in the Willamette and its tributaries for several months. |
| Juvenile to Adult Phase | 3-5 Years in the Ocean | 3-5 Years in the Ocean |
| Migrate from the Ocean | In Spring | In Fall |
| Spawn | Fall | Fall |
The Steelhead Trout (Oncorhynchus mykiss) can be found migrating throughout the year. Winter Steelhead are native to the area, leaving the ocean in the winter and swimming up the Willamette River in March and April to spawn in the spring, but Summer Steelhead that leave the ocean during the spring & summer and spawn in the winter have been introduced. Steelhead spawn in the area they were originally born, but do not die after spawning and may return to the ocean and come back to spawn again. Young Steelhead rear in the Willamette River and tributaries like Mill Creek for a year or two before migrating to the Pacific Ocean, where they live for another year or two before returning to spawn.
| Winter Steelhead | Summer Steelhead | |
| Juveniles | Stay in the Willamette and its tributaries for 1-2 years and then migrate to the ocean. | Stay in the Willamette and its tributaries for 1-2 years and then migrate to the ocean. |
| Juvenile to Adult Phase | 1-2 Years in the Ocean | 1-2 Years in the Ocean |
| Migrate from the Ocean | In Winter | In Spring and Summer |
| Spawn | March-May and may return to the ocean. | In winter and may return to the ocean. |
Although Cutthroat Trout (Oncorhynchus clarki clarki) in some areas do migrate to the Pacific Ocean, the Cutthroat in the Salem area cannot because Willamette Falls in Oregon City acts as a natural barrier to them. Fluvial Cutthroat spawn in streams like Mill Creek and migrate to larger rivers like the Willamette to fed and grow, while Resident Cutthroat live their entire lives in the same stream.
| Cutthroat Trout (Native) | |
| Juveniles | Fluvial – rear in large rivers, then migrate to smaller streams to spawn. |
| Juvenile to Adult Phase | 3 Years |
| Migrate from the Ocean | Our cutthroat trout cannot migrate past Oregon City due to the Willamette Falls and are thus landlocked. |
| Spawn | In Winter |
Mill Race Fish Screen on March 25, 2007
Because the artificial millrace is not an appropriate habitat for fish, the City of Salem installed a fish screen at the entrance to the millrace during the summer of 2003 to keep fish like the endangered Chinook Salmon and Steelhead from entering it. The openings in the screen are small enough that even newborn fish are unable to enter the millrace.
Mill Race Fish Screen on March 25, 2007
Adjustable tuning vanes behind the screen regulate the water flow to prevent fish from being trapped on the screen, and an automatic system of high-pressure nozzles keeps the screen clear of debris. A trash rack ahead of the screen prevents large floating debris from damaging the screen.
Waller Dam Fish Ladder on March 25, 2007
When the fish screen was installed at the entrance to the millrace, the Waller Dam's fish ladder was modified to make it easier for fish to go through it. The number of pools in the ladder was increased from 5 to 7 to lower the jump height between pools to about 8 inches. The pools are about 3 feet deep, and redesigned weirs ensure water always flows through them.
Waller Dam Fish Ladder on March 25, 2007
Additional Links:
Mill Race Dam at Discover-Neighborhood-History
Waller Dam from Mill Race Park on March 25, 2007
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