Another View: Conditions excellent for salmon returning to Auburn RavineBy: Jack Sanchez, Guest Columnist
Four years ago, Save Auburn Ravine Salmon and Steelhead (SARSAS) began scientific studies of fish living conditions in the Auburn Ravine. The studies centered around oxygen levels, flow levels, water temperature, pH rainfall, and available food within the ravine — all of which indicated the Auburn Ravine is excellent habitat for salmon and steelhead restoration.
Of course, there are problems with restoration — all man-made — such as flashboard dams, concrete dams, unscreened canals and pumps along the lower 18 miles of the Auburn Ravine.
After Nevada Irrigation District’s installation (with help from SARSAS, Placer Legacy and Dry Creek Conservancy) of a fish ladder at the Lincoln Gauging Station in the city of Lincoln, over 270 salmon spawned in the Auburn Ravine during the 2012-13 fall and winter. Two fish screens are scheduled for installation this fall at the Pleasant Grove Canal, the largest entrain of salmon and steelhead returning to the Pacific to mature. Unfortunately, only about 30 of these magnificent fish were able to get above the Hemphill Dam, located behind the Turkey Creek Golf Course 2 miles upstream from Lincoln, in order to spawn in the very best waters of the Auburn Ravine just east of Fowler Road.
It is uncertain how many salmon spawned in the Auburn Ravine during the 2013-14 fall and winter, a very dry year. Flows in the ravine were incredibly low due to the lack of rain; it is uncertain how many salmon were able to move above the Coppin Dam, approximately 15 miles west of Lincoln, to spawning gravels upstream from Lincoln. The salmon were at the Coppin Dam awaiting the removal of the flashboard dam, but by the time it was removed Oct. 15, the flow in the Auburn Ravine was too low for the salmon to move upstream.
But there is good news.
During the past two years, California Fish and Wildlife has been netting baby salmon (smolts) in the Auburn Ravine. They netted in two locations — at the base of the Hemphill Dam; and at the Aitken Ranch, about 3 miles west of Lincoln, where the Pleasant Grove Canal is located. The nettings were successful and led Fish and Wildlife officials to ponder where these documented falls, winter and spring run smolt came from. Were they all spawned in the Auburn Ravine? Did they come from somewhere else? These were perplexing questions. Fish and Wildlife drew several different conclusions.
One of the smolt had a clipped fin, indicating it had come from a hatchery. This identification led officials to speculate that this one fish, and perhaps others, had migrated downstream in the Sacramento River, then for some reason the smolt moved into and up the Auburn Ravine as far as the Hemphill Dam, some 22 miles from the Sacramento River.
And why would some smolt move in this fashion? Aren’t smolt supposed to migrate directly to the ocean from their natal spawning gravels? The obvious answer is a resounding affirmation. Then why would they head up the Auburn Ravine?
This is a perplexing question at best. Wildlife officials aren’t sure, but one thing they did state was they may have been drawn to Auburn Ravine because of the excellent conditions available to them — available foods, water temperature, oxygen and shade cover. In short, the Auburn Ravine is excellent habit for the restoration, rearing and successful spawning of fall, winter and spring run salmon. And the Auburn Ravine is possibly excellent habitat for smolt rearing from distant Northern California streams.
The news could not be better for restoring Auburn Ravine to an active salmon spawning tributary of the might Sacramento River.
Given the above conclusions, SARSAS knows that — with a solution
to the barrier at the Hemphill Dam and the screening of canals and pumps west of Lincoln — the thousands of salmon and steelhead that once spawned successfully in the Auburn Ravine will be able to do so again, and within a few years. Furthermore, the bonus can be successful rearing of smolt, whether from the Auburn Ravine or from other Northern California streams can occur.
These factors combine to make very good news for the successful returning of salmon and steelhead to the entire 33-mile length of Auburn Ravine.
Jack Sanchez of Auburn is founder and president of
Save Auburn Ravine Salmon