BY KAREN BOSSICK

As chocolate-colored floodwaters swirled around homes in Warm Springs, Gimlet and Hailey’s Della View neighborhood, the immediate response was to rush to save property with sandbags and stream alterations.

But on Wednesday and Thursday Wood River Valley residents were confronted with another reason to right the wrongs man has done to the Big Wood River over the years:

Namely, historic photographs of early valley residents holding dozens of trout measuring up to 30 inches and weighing 10 and a half pounds.

A caption on one picture said, “One Hour’s Catch.”

“Look at the size of these fish!” said Russ Thurow, a research fisheries scientist with the Rocky Mountan Research Service.

That was the norm in the days before residents began riprapping river banks with rock, Thurow told a standing-room-only crowd at Ketchum’s Community Library.

Not only have the residential trout in the Big Wood suffered from man’s meddling. But the entire fishery could be lost if something isn’t done to restore the habitat, he added.

Thurow, geomorphologist John Buffington and Dan Dauwalter, a fisheries scientist working on restoration projects related to climate change mitigation, spoke this week at two discussions sponsored by Trout Unlimited.

Natural rivers are inherently messy and require periodic flooding to replenish the habitat, said Buffington, who works with the Rocky Mountain Research Station in Boise. Rivers are interconnected with riparian forests, side channels, ground water and flood plain, which provides a relief valve allowing water to spread during flooding.

So you need to think in terms of a river valley, not just a river, he told listeners.

A dysfunctional river that has none of these connections is like a hyperactive child with excess energy to spare, resulting in damaging floods.

Historically, the Big Wood River was a very complex habitat with lots of woody debris in the river and overhanging the banks.

Locals called it “the Big Woody” for obvious reasons, said Thurow.

In the 1950s it was one series of big log jams after another with “many very large rainbow trout” in the pools formed by the jams, said longtime Wood River Valley resident Dick Alfs in 1985. In those days floods went way above the channels into the uplands. Lots of side channels helped disperse high flows.

But as people riprapped it, the river straightened, losing the meandering that once slowed high flows and trees that could deflect floodwaters, rather than allow it to erode river banks. And it lost its complex habitat as people began removing woody debris.

Dauwalter showed a picture of a bulldozer in the middle of the river taken during the 1960s which, he said, spurred research a decade later to examine man's impact on the river. Then he showed an aerial view of the Gimlet area south of Ketchum.

One photograph taken in 1943 showed a largely uninhabited area where water used to spill all the way to Highway 75 during flooding. A photo taken in 2004 showed the numerous homes that have been built in the area since.

Half the river from Magic Reservoir to the North Fork area north of Ketchum has had something done to it, including Boxcar Bend where boxcars were put into stabilize the riverbank.

In 1969 only 22 percent of the river had been altered. In 2016 a study by Jackson, Wyo.-based Biota showed that 52 percent of the river had been altered—a 30 percent increase in 47 years.

The Big Wood River is still beautiful and productive, ranking as the third most popular trout fishing stream in Idaho behind Henrys Fork and Silver Creek. Fishing brought $10 million to the local economy in 2011, with some of that money going to outfitters and lodging.

It’s been called the county’s greatest resource.

But there are between 80 percent and 95 percent fewer trout than there used to be. And today’s trout weigh in at 2 to 3 pounds.

The trout population could grow eight to 10 times if the habitat was restored and the size could increase to three to five pounds. And that’s just a start.

Problem is, standards are lowered with each generation because they lack historical knowledge. This incremental lowering of standards is called “shifting baseline syndrome.”

Perhaps, Wood River Valley residents need therapy to shift expectations back, Thurow suggested.

There are several things trout need: Connectivity with stream channels so they can migrate from one place to another depending on what they need. Sufficient water quantity. High quality water. Cold temperatures. Diverse pools. Complex cover. Intact riparian vegetation. And a healthy flood plain.

One way to restore the health of the river is to hang on to the natural river stretches that are already there, rather than allow further degradation, the speakers said.

Manicured lawns can be replaced with streamside buffers that will protect homes. Keep those manicured lawns right down to the river and you risk homes sliding into the river, Buffington said.

The practice of snagging or strategically placing logs in the river is making a comeback, Dauwalter said. Not only can logs slow down the energy of the river during flooding but they provide gravel for spawning, cover for fish from heat and predators. And they can regulate the transport of sediment.

Restoration needs to be planned, not reactive. They need to be collaborative, not individualistic, he added.

Dauwalter pointed to Napa Valley as evidence that areas with very expensive properties can make peace with rivers.

Napa Valley vintners planted vineyards in the flood plain, building berms along the river to protect their vineyards. But in 1986 it all came unraveled as high waters hit the berms and ricocheted, the river flooding the town.

Napa Valley residents spent $30 million to restore the river, removing berms and moving vineyards away from the river. Today the river is healthier than it had been for decades.

“It sounds a little daunting, devastating when I think what the Big Wood is today. But I also think we’re at a turning point,” said Keri York, of Trout Unlimited."We have a great opportunity to do something different."

Those spearheading the restoration of the river are looking at “reaches” of the river, such as the entire river corridor from Bullion Street to Colorado Gulch, rather than individual properties, she said. The Master Plan for the Hailey Greenway Project will be presented to the Hailey City Council at 4:30 p.m. Monday, Jan. 8.

Another stretch of river that’s being reviewed is near St. Luke’s Wood River.

Some property owners are taking restorative action, as well, York said. One homeowner, who lost 80 feet of his yard, leaving just 10 feet between the river and the front porch, hired Biota to come up with engineering solutions that benefit both him and the river.

“And the number of people who are showing up for events like this shows people are caring about the river,” she added.