Mapping out a new mindset/Studies indicate phosphorous occurs naturally
Recent geological studies may change many long-held assumptions, such as where to drill for water wells and the impacts of fertilizer and manure on Upper Klamath Lake’s water quality.
The Oregon Department of Geology and Mineral Industries released two geologic maps of Klamath Falls and Klamath County’s Upper Klamath Basin. Information gathering for the maps began in 1998.
“It’s very interesting to have an understanding of the geologic history, and it’s different than what we thought,” said Ian Madin, the department’s chief scientist.
Some key points
n Most of the volcanic activity that shaped the Upper Klamath Basin occurred within the past one to two million years. “If we go back three million years, it was pretty much as flat as a pancake,” Madin said.
n The upper basin has 464 volcanoes, which range from massive mountains like Shasta and McLoughlin to small cinder cones.
n Identifying fault lines, which typically are sources of underground water, improves the probability of locating and drilling less expensive, high-volume, water-producing wells.
n Many ridges and mountains previously thought to be lava flows that contain underground aquifers are actually thin layers of lava atop chalk rock, and are not good prospects for drilling successful wells.
n Higher than normal naturally occurring levels of phosphorus are responsible for reducing water quality in Upper Klamath and other lakes.
Ranchers and farmers who use fertilizers, and cattle manure, have historically been blamed for the unusually high phosphorus levels.
Madin said the findings involving phosphorus are important because steps to reduce fertilizer use or cattle grazing could harm crop production and ranching while having little or no impact on improving water quality.
Although the amount of naturally occurring phosphorus is small, 1 percent, he said the amount is 10 times higher than in other areas. Phosphorous is found in rocks, sediment and spring water.
“Some of that impact of phosphorous is natural. If a large percentage is natural and farmers are not allowed to use phosphorous fertilizer, it could have no impact on the water quality, but could be detrimental to farmers,” Madin said. “Changing when and how you till may have more impact than how and when you fertilize.”
Likewise, Madin stressed the importance of understanding the geologic history and identifying fault lines as being critical to “understanding the plumbing of the Basin.”
He said underground lava flows “are very much like pipes … finding them is a key to finding a reliable water supply.”
“We’re hoping that by pooling all this information in one place at one time it will help in the deliberations involving water,” Madin said. “That understanding is a key to determining how much you can extract.”
County Geologic Map
LEFT: The state released two geologic maps of the Klamath area. BOTTOM: Location map of geographic features. The Dotted line is the boundary of the geologic map. UGB is urban growth boundary.