CLEMENTS (CBS13) — A near record number of Chinook salmon are returning to the Mokelumne River for the second year in a row.

Normally about 9,500 Chinook Salmon make it up the Mokelumne River to spawn, but last year about 20,000 fish made it upstream. That marked the highest number of fish on record since 1940. Officials expect the numbers to get close to that again this year.

As soon as the gates open at the Mokelumne River Fish Hatchery in Clements, dozens of Chinook Salmon throw themselves at the rushing water to reach their final destination to spawn.

“Most of our fish are three and four-year-olds that come back here. So you can understand that turnaround of them leaving our facility, going out to the ocean, maybe Alaska and coming back here and then finding our river by the smell of the water,” said facility manager Darrick Baker.

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The facility, which was built by the East Bay Municipal Utility District (EBMUD) and is managed by the California Department of Fish and Wildlife, is once again on pace to reach or exceed last year’s record run for Chinook and Steelhead.

This is seen as a major accomplishment given how dismal returns have been over the last three years on many California waterways. For example, the Sacramento River saw it’s the lowest return in nearly a decade in 2017.

EBMUD Fisheries manager Jose Steka said a reason for the higher returns is due to the change in release strategies in recent years. Those strategies include cold water releases from the reservoirs, better management of hatchery fish, and habitat improvements in the river.

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Fish and wildlife technician Jason Shillam showed CBS13 how crews added gravel to the river and made more rearing habitat for the juvenile salmon.

Those measures are not only boosting fish populations in the Mokelumne but are making fishermen happy across California. Shillam said 20 percent of commercial harvest and 35 percent of recreational harvest were Mokelumne River fish.

So far, this year’s salmon count on the Mokelumne is only 1,500 fish below last year’s record numbers. Biologists said that if the region gets some good rain, it could lead to another last-minute surge in salmon following the scent upstream.