thespectrum.com
With wells at Quichapa Lake having dropped approximately 75 feet since 1990, officials in Cedar City and Central Iron County Water Conservancy District are planning for additional water resources they can develop in the near future with the hopes of taking stress off the aquifer that geologists insist is being over-mined.
sltrib.com
Big cracks are forming in the floor of Cedar Valley. They’ve already undermined one unfinished subdivision north of Enoch, and they’re still growing. One is 2.4 miles long. If unchecked, they could threaten Enoch itself, not to mention local roads and buried utility lines.
This is not a Halloween story, or the movie “Tremors.” It’s scarier, in fact, because it’s real. Fortunately, the Utah Geological Survey knows what the cause is, and if the people who pump water from the many wells in the area can cooperate, the problem is fixable. But a solution will require both community spirit and self-sacrifice, because people will have to use less water.
Since 1939, according to the UGS report, more water has been taken from the aquifer below Cedar Valley than Mother Nature has funneled back in. The water table has dropped by as much as 114 feet. This has caused the underground sediments in the aquifer to compact. The fissures and sinkholes visible on the surface of the ground are evidence of subsidence, that is, ground settling. The ground has sunk by as much as four feet over a broad area of Cedar Valley.
This settling has caused about 4 miles of cracks or fissures in the ground, particularly in the area of Enoch (north of Cedar City) and around Quichapa Lake. There may be other fissures that are not yet visible.
Salt Lake Tribune
Since 1939, the Cedar Valley spreading west and north of Cedar City has dropped 100 feet and the only way to stop or slow the process is replenish the underlying aquifer with at least as much water as is being discharged through pumping.
That was one of the statistics the Utah Geological Survey delivered to the Central Iron County Water Conservancy District at its board meeting Thursday night in Cedar City.
William Lund, senior scientist with the agency’s southern Utah office, said the practice of overpumping causes noticeable fissures in the ground that sink all the way to the water table and allow pollutants to seep into the water. Most of the water is now used for agriculture, but officials are concerned about polluting the water source should it be needed for other uses.
“They start as a hairline crack and fast erode into gullies,” said Lund of the fissures.
He noted a fissure first noticed in 1960 northeast of Enoch has grown 2.25 miles long and has snaked its way into a subdivision where home construction was set to begin.
Although only one structure was built and affected by the fissure, it has disrupted the infrastructure that had already been completed, including cracking curbs and gutters, streets and the sewer system, which now runs backward.
Lund said it is the only location in Utah he is aware of that has been damaged by a fissure.
Lund’s updateis part of an $85,700 study the Geological Survey is conducting in conjunction with the conservancy district. The agency is nearing completion of its final report after nearly two years of study.
CORRECTION
Cedar Valley has not dropped 100 feet! (it has subsided 4 feet at the most). Erroneous information was reported by most of the media. Please note the Utah Geological Survey’s following corrections to
IN THE MEDIA
thespectrum.com
Reports from the Utah Geological Survey top the agenda for Thursday’s Central Iron County Water Conservancy District meeting. Geologist Bill Lund is presenting information about water subsidence in and fissures found in Enoch, which is part of the study.
Lund said the study is almost complete and so far concludes that the water table in the area of Enoch near Midvalley Road is permanently lowered because of overdrawing water from the aquifer resulting in the fissures.
“Basically, we are going to summarize what we’ve found to date,” he said. “We’ve found more fissures and land subsidence.”
The Utah Geological Survey (UGS) is a division of the Utah Department of Natural Resources. Several specialized programs comprise the UGS: Data Management, Energy & Minerals, Geologic Hazards, Geologic Information & Outreach, Geologic Mapping, Groundwater & Wetlands, and Paleontology.