Project highlights complex nature of cave geology
The shortest distance between the headwaters above the north rim of Glenwood Canyon and the canyon’s most iconic feature, Hanging Lake, is anything but a straight line.
Along the way, a portion of that water takes a detour underground through the canyon’s expansive karst system before making its way back to the surface.
How much of that groundwater ends up in Hanging Lake, and from where, versus how much flows into the lake directly from the surface are still questions to be answered, water scientist David Woods said.
“It has been theorized that the water in Hanging Lake has been in the ground for a very long time, but what we’re seeing is that at least some of it has not been in the ground long before it enters the lake,” said Woods, who is leading a project to try to pinpoint Hanging Lake’s water sources.
Woods and his team of researchers from Ozark Underground Laboratories, which specializes in tracing water sources, have released their initial findings in the study that began last fall following the devastating mud and debris flows in the canyon, which resulted from heavy rains over the 2020 Grizzly Creek burn scar.
“The Grizzly Creek Fire highlighted the need for the Forest Service to better understand the hydrology of the area to help protect the source water for Hanging Lake,” said Leanne Veldhuis, Eagleholy Cross District ranger, in a release announcing the source water progress report.
Researchers began a dyetracing investigation last fall, establishing 11 dyetracing stations at Hanging Lake and surrounding areas. Unique tracer dyes were then placed in three areas above Hanging Lake — the East and West forks of Deadhorse Creek, as well as the adjacent, but physically separate, French Creek drainage.
This spring, tracer dye introduced into the West Fork of Deadhorse Creek was detected in Hanging Lake, even though there is no surface connection between the two, Woods said.
Because the confluence between the West Fork and East Fork of Deadhorse Creek is below Hanging Lake, that finding establishes a groundwater connection between West Fork and the springs that supply water to Hanging Lake, he explained.
Surface water does enter Hanging Lake from the East Fork of Deadhorse Creek, where the nearby Bridal Veil Falls is located. However, dye introduced into that drainage was not detected in Hanging Lake or any of the sampling stations downstream in Deadhorse Creek, Woods said.
That may have been a result of the time of year, late in the summer season, when the initial dye research was conducted, he said.
Interestingly, the study also established a groundwater connection from the East Fork of Deadhorse Creek to the neighboring French Creek drainage. That’s solely the result of groundwater flow between the two basins, Woods said. study
and chanted along the Pearl Street section of Broadway Street. Motorists in many cars driving down Broadway honked to acknowledge the protesters.
The march ended back at the courthouse for closing words and an invitation to another march at 1 p.m. in Longmont. The second march was led by Longmont Leads with Love and took place at the intersection of Sixth Avenue and Main Street.
Greeley resident Emmalyn Schwartz, 24, heard about the Longmont march at the end of the Boulder event and decided to attend both events.
“This is so important for me, and in my opinion this should important for everyone,” Schwartz said.
While this march had fewer people attending than in Boulder, Kathy Clegg, who works with Longmont Leads with Love, said the previous week’s protest was more crowded, with around 100 people congregating.
Despite the smaller turnout, many drivers honked and flashed thumbs-ups at the protesters as they crossed the intersection. Several flags, including the Pride and Black Lives Matter flags flew alongside the group.
“We have to get young people out to vote — elections are coming up,” Clegg said.