Probing – 03 Promise of Protection

Probing the Depths of Crater Lake: A Century of Scientific Research by Douglas Larson

Unfortunately, the promise of protection would apparently be broken at Crater Lake. During the early 1980s, limnologists-scientists who study the physical, chemical, and biological properties of lakes-discovered that the lake was being contaminated by sewage coming from the park’s antiquated septic tank-drainfield system on the caldera rim. What followed was a lengthy, sometimes bitter scientific debate over the source of the contamination and its effects on the lake’s extraordinary limnological attributes. Finally, in 1987, the National Park Service admitted that sewage was probably entering the lake, although the agency continued to insist that no harm had been done. Some scientists disagreed, arguing that the Park service’s claim was based on speculation rather than on hard scientific evidence. The debate ended in a deadlock, with neither side able to prove its argument.”

The question of whether sewage contamination had altered the lake was never resolved. Scientists on both sides of the debate sought to answer the question by comparing the lake’s existing limnological attributes with those described by researchers who had studied it over the previous hundred years. They discovered that historical information about the lake was exceedingly sparse and fragmentary, making it virtually impossible to determine if and to what extent the lake had changed. Between 1902 and 1982, the lake was studied by only a handful of scientists, most of whom were not associated with the National Park Service. In fact, no Park Service limnological monitoring and research programs existed at Crater Lake until 1983 when the agency was forced to address the problem of sewage contamination.

A car parked on the rim on Crater Lake in 1937. Photo courtesy of the National Park Service