The Roaring Fork in the Cascades midday on June 14, 2017, when the Twin Lakes Tunnel under Independence Pass was still diverting. Credit: Brent Gardner-Smith/Aspen Journalism

The roar was put back in the upper Roaring Fork River this week as the Twin Lake Reservoir and Canal Co. curtailed its diversions near the top of Independence Pass and let more water flow in the river through Aspen and down to the Colorado River.

The water returned to the river first makes its presence felt in terms of volume, as the Roaring Fork River above Difficult Creek east of Aspen climbed from about 200 cfs Tuesday to about 600 cfs by Thursday morning, swelling the slow-moving section of river through North Star to the upper limit of its banks.

The higher flows in the river as a result of Wednesday’s curtailments had not caused any problems in the valley as of midday Thursday, Pitkin County emergency manger Valerie MacDonald said.

“We still urge caution for people recreating in and around the river,” MacDonald said. “While many in the local community may appreciate the restoration of the natural flows in the river, the swift current, the cold temperature of the water and the now-slippery banks and rocks can catch visitors unaware.”

Placid, then pulsing


The Roaring Fork River, in the Cascades, on Independence Pass, at midday on Wednesday, June 14, 2017. The Twin Lakes-Independence Pass Tunnel was diverting about 600 cfs when this was taken.


The Roaring Fork River in the Cascades on Independence Pass at midday on Thursday, June 15, 2017. The Twin Lakes-Independence Pass Tunnel, which normally diverts around 600 cfs, was closed when this was taken.

This is the third consecutive year the company curtailed its transmountain diversions from Lost Man Creek, Lincoln Creek, and the Roaring Fork due to legal and physical constraints.

But prior to 2015, closing what’s officially called Tunnel No. 1 of the Independence Pass Transmountain Diversion System has been a rare occurrence.

It is not clear how long it will be before Twin Lakes Co. starts diverting again, lowering flows in the Roaring Fork.

“Once flows in the Arkansas [River] start to drop, which they will eventually, that will create more demand for Twin Lakes water and then we’ll start taking some more,” Twin Lakes Co. President Kevin Lusk said. “But in terms of how much and when, it’s really up to the weather and the different shareholders, in how they are managing their supplies.”

Lusk is aware that curtailing diversions may increase the chance of flooding in the Roaring Fork River basin.

“There’s always concerns about flooding and managing flows, but there is only so much that we are legally able to do,” he said.

Last year, the tunnel was closed from June 14 to June 28.

A map from the ongoing Roaring Fork River management plan showing the area and features of the Twin Lakes -Independence Pass diversion system. It also shows that the Lincoln Creek basin is as significant as the main stem of the Roaring Fork to the upper river system. Credit: City of Aspen/Seth Mason, Lotic Hydrological
A map of the Independence Pass Transmountain Diversion System, as submitted to Division 5 Water Court by Twin Lakes Reservoir and Canal Co. Credit: Source: Div. 5 Water Court
A schematic of the Independence Pass Transmountain Diversion System included in a 2015 water court case, 2015CW3050. Credit: Twin Lakes Reservoir and Canal Co.

East, then west

About 600 cfs of water from the Roaring Fork River basin flowing out of the east end of the Twin Lakes-Independence Pass Tunnel on June 7, 2017. On June 14, the water would flow toward the Gulf of California, not the Gulf of Mexico. Credit: Brent Gardner-Smith/Aspen Journalism
The Roaring Fork River, at the bottom of the Cascades, heading west, on June 15, 2017.

At dawn Wednesday, 598 cfs of water coursed out of the Twin Lakes Tunnel on the eastern slope, as usual, after having entered the tunnel at Grizzly Reservoir on Lincoln Creek on the west slope. (Technically, it is Tunnel No. 1 of the Independence Pass Transmountain Diversion System.)

But by noon, there was just 5 cfs flowing through the tunnel.

The gauge reading from the Twin Lakes – Independence Pass Tunnel.

Correspondingly, the flow in Lincoln Creek below Grizzly Reservoir went from a trickle of 2.8 cfs at the start of Wednesday, and ended the day at 319 cfs, which is enough water to make it hard to wade across.

And the rest of the water was being released down Lost Man Creek, the main stem of the Roaring Fork, and three creeks that run into lower Lincoln Creek.

At 10:30 a.m. Wednesday, the tunnel under Independence Pass was fully closed and water was instead collected and slowly released out of Grizzly Reservoir, with all of the water fully turned out by 9:30 p.m.

The gauge reading shows Lincoln Creek going from 3 to 300 cfs on June 14, 2017.
The gauge reading shows the Fork above Difficult Creek climbing from 200 cfs to 700 cfs over June 13 to June 14, 2017.
Graph from the gauge maintained by ACES just above the Mill Street Bridge in Aspen, at Rio Grande Park. The flow basically doubled, going from 400 to 800 cfs.

Lincoln, Roaring

Lincoln Creek and the Roaring Fork come together just below Lincoln Gulch Campground and just above the Cascades at the Grottos area on Independence Pass.

At 8:25 p.m. Wednesday, as the front edge of the flow of released water in Lincoln Creek reached the confluence with the Fork, the last stretch of Lincoln Creek quickly went from walkable to swimmable.

The rising water took down a pile of rocks placed by passersby in what, the day before, had been a placid little stream. Now Lincoln Creek was a cold rushing river again, intent on joining the Roaring Fork to head together to the Gulf of California.


A short clip of Lincoln Creek on June 14, 2017, just above the confluence with the Roaring Fork River.

Lincoln Creek, just above its confluence with the Roaring Fork River, on June 14, 2017. Passersby had left rock piles in the clear, warm, and shallow stream. Credit: Brent Gardner-Smith/Aspen Journalism
Lincoln Creek, just above the confluence with the Roaring Fork, June 15, 2017. Credit: Brent Gardner-Smith/Aspen Journalism
Looking down Lincoln Creek at its confluence with the Roaring Fork, on Wednesday, June 14, 2017. A pleasant place to pile stones, apparently. Credit: Brent Gardner-Smith/Aspen Journalism
Lincoln Creek, at its confluence with the Roaring Fork, on Thursday, June 15, 2017. Credit: Brent Gardner-Smith/Aspen Journalism


The same location as above, a day later, on June 15, 2017, but initially looking downstream, not up. Note the cloudy, deep water. The little rock piles (see below) would be in the frame, but they are now submerged. And one would think twice before trying to wade across, given the volume and depth of the water.

Also, please see a 3-minute video of Lincoln Creek rising as the front edge of the flow reaches the rock piles at its confluence with the Fork, at 8:25 p.m. Wednesday, June 14, 2017: https://youtu.be/YkchIo3mZU4.

Cascades cascading

The Cascades, cascading, on June 15, 2017. Credit: Brent Gardner-Smith/Aspen Journalism

Around the corner from the confluence of the Lincoln Creek and the Fork are the Cascades, which went from mild on Wednesday afternoon to wild by Thursday afternoon when whitewater poured over the rocks in a renewed frenzy of foam and spray.

In addition to adding volume to the river and creeks, the return of natural flows brings the Roaring Fork headwaters back to life, adding an urgency and vibrancy to the flow that’s been missing since the Twin Lakes diversion system was built in the 1930s.

The system originally sent water to sugar beet fields in the Arkansas River basin, but most of the water today goes to Colorado Springs, Pueblo, Pueblo West, and Aurora.

Colorado Springs owns 55 percent of the shares in Twin Lakes Co., Pueblo 23 percent, Pueblo West 12 percent, and Aurora 5 percent. There are also other minority shareholders, holding 5 percent of the shares, still using the water from the system for agriculture.

In the 10 years from 2007 through 2016, Twin Lakes Co. diverted a total of 485,762 acre-feet of water from the upper Roaring Fork River basin through its diversion system, with 2011 the highest year since 2007 with 67,463 acre-feet diverted and 2015 the lowest year since 2007 with 18,374 acre-feet diverted.

The water rights held by Twin Lakes Co. have limitations that can cause it to stop diverting, including a junior diversion right on the Colorado Canal, which takes water from the Arkansas River near Ordway, and the amount of water in Twin Lakes Reservoir, which is owned and operated by the Bureau of Reclamation.

In short, when flows in the lower Arkansas River are relatively high and the Colorado Canal can use “native water” from the east slope, and the Twin Lakes Reservoir is full, the Twin Lakes Co. cannot divert water under Independence Pass.

The water rights for the diversion system have an appropriation date in 1930 and an adjudicated decree from 1936.

‘Compare and contrast’

A few sets of photos comparing flows on June 14 and June 15, 2017.

The Roaring Fork River just below the pedestrian bridge at the Grottos day-use area, midday on June 14, 2017. Note the gravel bar on the left and the clear water. Credit: Brent Gardner-Smith/Aspen Journalism
The Roaring Fork, from the Grottos bridge, at midday on June 15, 2017. Note the gravel bar is covered, and the cloudy color of the water as the river changed from stream to river. Credit: Brent Gardner-Smith/Aspen Journalism
A Lincoln Creek logjam on June 14, 2017. Credit: Brent Gardner-Smith/Aspen Journalism
Lincoln Creek logjam on 6.15.17. Credit: Brent Gardner-Smith/Aspen Journalism
A streamside shelter on the beach at Lincoln Creek on June 14, 2015. Credit: Brent Gardner-Smith/Aspen Journalism
A crude shelter on Lincoln Creek on June 15, 2017. Much cooler seat than before … Credit: by Brent Gardner-Smith/Aspen Journalism
The Cascades, 6.14.17, with upstream diversions still largely in effect. Credit: Brent Gardner-Smith/Aspen Journalism
Cascades, 6.15.17, with the diversions closed. Note that the polished rock along the Cascades is very slippery when wet. Credit: Brent Gardner-Smith/Aspen Journalism

Links to gauges

Twin Lakes Tunnel
Tunnel No. 1 of the Independence Pass Transmountain Diversion System, which is owned by the Twin Lakes Reservoir and Canal Co.

The east end of the Twin Lakes Tunnel on June 6, 2016. The four-mile long tunnel brings water from Grizzly Reservoir to Lake Creek, Twin Lakes Reservoir, and on to Front Range cities and fields. Credit: Brent Gardner-Smith/Aspen Journalism

Lincoln Creek below Grizzly Reservoir

The spillway at Grizzly Reservoir directs water into Lincoln Creek. Credit: Brent Gardner-Smith/Aspen Journalism

Roaring Fork River above Difficult Creek

The Roaring Fork River crashing through the Grottos, spring 2016. Credit: Brent Gardner-Smith/Aspen Journalism

Roaring Fork River above Salvation Ditch
Located at Stillwater Drive. Good gauge for flows in Stillwater/Northstar section of Fork.

An Aspen resident on June 17, 2015, enjoys the newly formed backwaters of the Roaring Fork River along the Stillwater section east of Aspen. Credit: Brent Gardner-Smith / Aspen Journalism

Roaring Fork River below Salvation Ditch, at Mill Street
Subtracting this gauge from the gauge above approximates Salvation Ditch flow

The Roaring Fork River, just above the John Denver Sanctuary, in July 2012. Credit: Brent Gardner-Smith/Aspen Journalism

Roaring Fork River below Maroon Creek
This gauge, which was used to judge Slaughterhouse and Toothache, is now inactive.

The rapid known as Snowmass Hole on the Toothache section of the Roaring Fork River is one of the highlights for local rafting customers. Credit: Brent Gardner-Smith

Roaring Fork at Emma/Willits

Fryingpan River below Ruedi
Subtract this gauge from Emma gauge to determine flows in Basalt kayak park on the Fork.

The Fryingpan River flowing at 298 cfs on Wednesday, Aug. 31, 2016. Credit: Brent Gardner-Smith/Aspen Journalism

Twin Lakes Reservoir levels

The Twin Lakes Reservoir in Twin Lakes, Colo., plays a key role in moving water from the Roaring Fork and Fryingpan rivers to cities on the Eastern Slope. Credit: Brent Gardner-Smith / Aspen Journalism

Colorado Canal
This is the Avondale gauge on the Arkansas River. When it’s below 3,000, the Colorado Canal is likely to be out of priority, which means Twin Lakes Reservoir and Canal Co. can divert again through the tunnel under Independence Pass, if there is room in Twin Lakes Reservoir to first accept the water.

The Colorado Canal in March 2016. Credit: Brent Gardner-Smith, Aspen Journalism

Editor’s note: Aspen Journalism is collaborating on coverage of rivers and water with The Aspen Times, the Glenwood Springs Post Independent, the Vail Daily, and the Summit Daily News. The Times published a version of this story on Friday, June 16, 2017, as did the Vail Daily.

Brent Gardner-Smith, the founder of Aspen Journalism, and who served as AJ’s executive director until August 2021 and as editor from 2011-2020, is the news director at Aspen Public Radio. He's also been...