Airborne electromagnetic study to give critical look into aquifers, underground geology in eastern El Paso County
To someone who didn’t know better, the helicopter flying low over eastern El Paso County on Thursday was an odd sight — doing little more than pulling an oversized hula hoop underneath it.
But officials with the Upper Black Squirrel Creek Ground Water Management District and Wyoming-based Aqua Geo Frameworks know the reality.
The SkyTEM 304M System comes in for landing after its second of three calibration flights at Meadow Lake Airport near Peyton, Co., on Thursday.
They’re performing an electromagnetic survey and that hoop — actually a hexagonal sensor — will provide water management district, El Paso County and state officials critical information about the aquifers and underground geology of the Upper Black Squirrel Creek Designated Ground Water Basin that spans 354 miles of east-central El Paso County, from Black Forest to just south of Ellicott.
For about a week the helicopter will fly low, not more than 200 feet above the surface, in designated flight paths across 790 line miles.
The sensor it carries allows officials to look below the earth without ever disturbing the soil, pulsing electromagnetic frequencies into the ground and measuring how easily they travel and interact with sand, gravel, clay, shale and other materials, said Jared Abraham, a geologist and geophysicist with Aqua Geo Frameworks, the company conducting the study.
The helicopter will travel about 55 mph, collecting detailed information up to 1,000 feet below the ground, he said.
The 3-D map of the basin it produces will help officials better understand its underlying geological framework, which can affect groundwater in many ways, such as blocking water flow into and out of aquifers or affecting water quality as water is exposed to various rocks and underground materials.
“We’re trying to get empirical data to be able to draw a conclusive picture and have the best ideas of how to preserve and conserve this aquifer for many generations to come,” Dave Doran, president of the Upper Black Squirrel Creek Ground Water Management District, told reporters before the flights began near the Meadow Lake Airport in Peyton.
Underlying the Black Squirrel’s alluvial aquifer are the Denver Basin bedrock aquifers, Doran said, which are virtually non-renewable water sources. The alluvial aquifer has been heavily used in past decades for agricultural purposes and now mainly serves booming development and many thousands of people living in eastern El Paso County.
“We know that development is going to continue. The only way it can go is east,” he said. “But there’s a smart way to doing development. This tool will help us give better advice going forward on how we continue to grow and how we utilize those resources.”
A map of the area the SkyTEM 304M System will be mapping sits in a building at Meadow Lake Airport on June 8, 2023.
The amount of water in the basin has been studied and estimated, said Mike Wireman, a retired EPA groundwater expert and consulting hydrogeologist for the groundwater management district. Officials know the depth of water in the alluvial aquifer has “declined significantly” since the 1950s and 1960s, and what’s left is declining, too — but the actual quantity isn’t known, he said.
Abraham said the 2,000 or so wells in the groundwater management district area give officials “an idea” of how much water there is. The electromagnetic study will hopefully provide more information about the amount of water available as well as details about how groundwater resources are interacting with the geology under the surface, he said.
“The problem is the distance between those wells is variable,” he said. “Maybe it’s several hundred feet in some cases and maybe it’s miles in others. The question arises, when difficult and detailed questions are asked about the aquifer, ‘What’s going on in between?’ What a lot of this technology does is help fill in the gaps between our control points.”
The Upper Black Squirrel Ground Water Management District is funding the study, which cost about $400,000, Doran said.
It is happening concurrently with two others the U.S. Geological Survey is conducting for the district, including a water quality study and a water level study, officials said.
The SkyTEM 304M System is prepared for takeoff by the crew before its second of three calibration flights it will take at Meadow Lake Airport near Peyton, Co., on Thursday, June 8, 2023.
The SkyTEM 304M System is lifted into the air by a helicopter for its second of three calibration flights at Meadow Lake Airport on June 8, 2023. near Peyton, Co., on June 8. The system will scan El Paso County from the skies to study a geological make-up of the ground and create maps of aquifers and minerals in the area.
A taped on smile decorates the open field magnetometer on the SkyTEM 304M System on Thursday, June 8, 2023.
