Good Morning! 57F @ 6:30AM. Rain and wind. High 57F. Winds S at 20 to 30 mph. Chance of rain 100%. 1 to 2 inches of rain expected. Localized flooding is possible.
Farmer, the
height of the dam is 742', and the maximum reservoir height above sea level is 900'. I think I read yesterday that it's either the tallest or second tallest earthen dam in the US. Current reservoir height is 874', and it's come up by 25' in the last three days. Keep in mind that the V shape of the canyon means that progressively more water is required to fill each additional foot, but even so it's gonna be close as to whether or not the spillway is repaired before it's needed. They did some testing yesterday at 15,000 CFS and determined it was safe to use at that rate of discharge, but from the looks of the photos I don't see how they can say that. Inflows are ranging in the 100,000 - 120,000 CFS in the last 12 hours, so 15,000 CFS isn't gonna do much to keep the dam from overtopping. Eric, I'll pass your contact info along in case they want to bring you in as a siphon consultant. :laughing: I would never purchase property below a dam. I've read about all the early earthen dam failures, and many years ago visited the old St. Francis dam site. At first I didn't recognize the name in the article Eric cited, as the signs on site call it the St. Francisquito Dam. There's not much left but big blocks of the dam's foundation, and the flood channel is now all grown up with brush and trees. The observation point is on a highway bridge crossing the channel, so you can look upstream to the dam and downstream to the populated areas that were flooded. The flood must have been horrible in its destruction, and it impressed upon me the importance of avoiding flood channel building sites! This place sits at just shy of 1200' elevation,
overlooking the flooded canyon.
Also mentioned in the report was the 1975 earthquake below Oroville Dam. I didn't see mention of the cause in the report, but when researching earthquake activity in this area prior to purchase of this house, a pattern of earthquakes was observed that coincided with the release of water during the summer months. The theory was that the earth beneath the water was being compacted during the time after the initial filling in 1969, and this pressure was released when the reservoir was drained in the subsequent dry summers to such a level that the ground rebounded, causing the quakes. It's good to note that there have been no earthquakes in the last two years of record low reservoir levels, so I guess that the ground has reached a stable state of compaction.
Made good progress yesterday on the van's headlight mounts. Had to reshape the headlamp buckets to create mounting tabs for the headlight lenses. The tabs for the trim rings that the buckets were designed to work with interfered with the mounts for the grill, and that would prevent the headlamps from being adjusted. The headlight lenses I ended up with have mounting tabs on the back, so I was able to drill and tap them to mate with the new tabs on the buckets. Match drilling the holes in the tabs was tedious and slow going, so I still have the other bucket to do the same way. I also need to drill holes for and mount the adjusters, so that's what'll keep me busy today. I was gonna head into town, but may end up sitting out this storm here and avoiding the wind and heavy rain out on the roads.
Hope everybody in the storm's path along the eastern seaboard has enough sense to take it easy today.