An interview with C.V. Theis

Abstract

Every serious hydrogeologist is aware of the Theis Equation. I was fortunate enough to have known C.V. Theis—“C.V.” to his friends (Fig. 1). I interviewed him in December 1985 for the video that is being included on the International Association of Hydrogeologists’ (IAH) Time Capsule website (IAH 2007). It is my intent, in this article, to provide background comments for the website interview. For those interested, White and Clebsch (1994) provide a biography of Theis. I was first aware of Theis as an individual when my PhD advisor, Burke Maxey, was appointed to the Atomic Energy Commission (AEC) Containment Panel in the early 1960s. The US was testing nuclear devices underground at the Nevada Test Site. Several of the early underground blasts were not contained in the subsurface; the shots vented to the atmosphere, releasing radioactive clouds. One of these had disastrous consequences. The AEC determined that this should not continue to happen. They created the Containment Panel, a panel of experts, to advise them on subsurface conditions at the Nevada Test Site; many of the experts were geologists and hydrogeologists. Among the panel members were Theis, M. King Hubbert, and Harold A. Thomas (Head of the Water Program at Harvard University, Massachusetts). Maxey got to know Theis through this work. Maxey had a colleague at the Illinois State Geological Survey, Al Bell, who was head of the Oil and Gas Section. Al’s wife Dorothy had been a graduate student colleague of Theis, and a close friend, at the University of Cincinnati, Ohio. Dorothy liked a good party as did Maxey and Theis. On occasion Theis would visit the Bells in Champaign, Illinois—invariably a party would result. Maxey’s graduate students were like his extended family. All were included in whatever festivities, including the Bells, and on occasion Theis. In 1962, following my PhD studies, I went to work at the US Geological Survey (USGS) in the research program in groundwater in Washington, DC, where I apprenticed with Bob Bennett. Bob was the first director of the nationally funded groundwater research program at the USGS; he was widely respected by the groundwater community within the Survey. When prominent hydrogeologists visited the USGS Washington Office, as they inevitably did, they often came by to talk with Bob; I met these individuals, including C.V. Theis. Later I shared an office complex with Bob, Hilton Cooper, Stavros Papadopoulos, and George Pinder. Hilton was a good friend of Theis. They both did the math puzzles in Scientific American every month, and shared their results. On a number of occasions Theis visited our office; he was personable, with a good sense of humor, and an ego—but not an inflated sense of himself. One of my early assignments was to investigate the impact of the Good Friday Earthquake, Alaska (27 March 1964) on water wells in the lower 48 states (i.e. mainland states south of Alaska). Many wells responded to the earthquake, some very dramatically—one well in Florida fluctuated 10m (30 ft). A number of the wells that responded to the earthquake also had good earth-tide signals. If we could understand the earth-tide response in the well, we might have a means tomeasure the volume strain of the rock. I wrote a manuscript on the earth-tide response in wells, which Hilton Cooper encouraged me to send to Theis for his review. Theis pointed out that I had not adequately accounted for the pressure change in the fluid as the rock was strained by the tidal potential. This incident impressed on me Theis’ great intuition on how groundwater behaved in rocks, even his understanding of rock mechanics.