I spoke with Kathy Barton yesterday from Inyo Environmental Health. Got pretty much the same story about the spring flow decreasing dramatically and popping up at a new spring nearby. She described the old spring as being between the trailhead and the store, further up the hill, but I can't say that I understood her for sure. I couldn't understand where the new spring has sprung up.
The geotechnical engineer in me suspects the spring flow may have shifted due to the record drought followed by a record snow year. That's a big and sudden swing in infiltration that can cause groundwater conditions to change. Water is stored in the joints and cracks of the granite, which can become clogged when flow rates change due to precipitate from minerals in the water, or due to fine grained soil transport, or it can move material and find new pathways to new springs. Its also possible that a screen might be clogged that's blocking flow into the springbox, but I have a hard time with that one, and it could be easily remedied to restore flow. As Bob was saying, earthquakes often change groundwater flow, especially right after an earthquake, but there hasn't been any significant ground motion in the Whitney area recently. I suspect its related to the sudden dramatic change in infiltration rate. As for the source of the E Coli, who knows. The concrete springbox was built in the 1930s and probably leaks, which would let exterior flow in. In any case, they could, and should, do some specialized tests to see if its human or animal.
Apparently Inyo is working to develop the new springs and they hope to have it done this season. I asked about the E coli test results, but Kathy didn't have any numbers on that and didn't know about any more recent testing. She didn't think the contamination was coming from the creek since its lower than the spring, but nothing seemed very definitive.
Here's an interesting study done by the Lahontan Regional Water Quality Control Board testing E Coli from creeks flowing off the Eastern Sierra slopes. It's mainly focused on cattle pollution, but you can learn a lot about E Coli in the area from this report. The testing protocols used were able to distinguish between human and animal sources.
