Trip date: 10 January 2015
Project manager: Bill Gee
Trip purpose: Service the data loggers
Areas of Cave visited: Upstream Thunder
Trip participants: Austin Toler, Jack Peters, Grace Welch, Roger Preston, Cliff Gill
Entry Time: 10:00am
Exit Time: 3:30pm
The trip report: This is the annual trip to download all of the stream flow data loggers in the cave. Once a year I have to download all of them together so I can generate the full-year graphs.
Everyone met at the silo at 9:00am. Jack and I drove down and arrived quite early. We had to use a propane heater to thaw the keysafe. The entire inside of the silo was covered in frost. Once we had the keysafe defrosted, we opened the hatch to the cave. The airflow was quite strong and within 10 minutes or so the frost had all melted. Of course, that made a wet mess on the floor including a patch of ice just inside the silo door.
I rigged the rope, then got out my laptop and serviced the rain gauge logger. It downloaded with no problems. I replaced the battery (an annual task) and restarted it. About that time people started showing up. We all geared up and started down the shaft. Everyone was in the cave by 10:20am.
Back in October I tried to download three of the loggers in the cave. Two of them failed. I suspected low or bad batteries. For this trip I packed a laptop computer in a Pelican case. That let me check the logger batteries while still in the cave.
I attempted to download the barometric pressure logger at the ladder. It failed to even try, going immediately to a red light on the data shuttle. This is the same as what it did in October during the bat census trip. It seems most likely that the battery is dead.
All of us went down to the river where I grabbed the data logger in the stream. We spent about five minutes looking for isopods. A couple of fish were seen at the riffle just downstream from the stilling well. Back at the ladder, I did a download of the data. I then started up my laptop computer and connected the logger so I could check the battery state. The computer reported the battery as very low. So far we are two for two loggers that need servicing.
The trip to the logger in Carroll River took about 30 minutes. We stopped along the way to admire formations. Cliff took many photos with his new camera.
The Carroll River logger started to download but would not finish. I hooked it to the computer and found that its battery was even lower than the Thunder River logger. Into the pack it went, destined for a trip to the service center.
We arrived back at the ladder about 12:10pm. After a sandwich lunch break, we headed out for UL2 and the last data logger. Since we had three of the four loggers requiring service, I decided there was no point in hauling the laptop all the way to UL2. We would simply grab the logger and return. It has been in the cave for five years which is about the expected life of the batteries. Good or bad, it was going to go in for service along with the others.
Data from the in-stream loggers is not much use without the barometric pressure data. The raw data has to be adjusted for barometric pressure in order to get anything resembling good data on the water depth. The temperature data is interesting but says very little about how the stream level changes in response to rain events.
On the way out of UL2 we stopped to admire formations. Cliff took many more photos. We stayed in the stream all the way to Thunder Falls where we did the usual tourist stuff for Grace.
On the way back to the ladder from Thunder Falls, we discovered a trash deposit under a rock. This rock is just 10 or 15 feet from the natural bridge between the landing area and the Carroll Passage. We moved all the trash over to the landing area. Some of it was removed, but one heavy jug is still there for another team to deal with. One of the trash items was a VERY old jar of peanut butter! We also saw a grotto salamander amidst the trash.
We got back to the ladder about 3:00pm. Everyone geared up and was out of the cave by 3:30pm.