The failure and near failure of dams, both big and small, has been in the news of late. Just last week, Lynchburg, Va. was evacuating residents over concerns a large dam in the city was going to fail, releasing a 17' high wall of water through the small city; it didn't, but it was a scare. Generally, a dam fails with lots more water than it can handle over its spillway eats away at the side and then back of the dam. The spillway is designed to get the excess runoff way away from the back of the dam. A blocked or compromised spillway seems like an easy way to increase the chance of dam failure.
Well, James River Forestry has put the perfect plan in place to dramatically increase the failure chances of the dam holding back the pond on the property adjacent to (and upstream of)me. I had seen where they had driven onto the spillway mud where it met the pond making some nice mosquito breeding ruts (had to have a couple of 8" maples); that concerned me. Today they have furthered their dam failure plan with a two prong attack: first, they drove across the spillway farther away from the pond to cut trees on the steep bank behind the pond, leaving more ruts and disturbed soil AND then filled in the spillway with a variety of cut trees guaranteeing that runoff with not flow down the spillway (and way away from the dam) but will seek a new channel in the freshly disturbed soil directly behind the dam. Short of filling in most of the spillway with dirt and ditching out the steep bank behind the dam, I'm not sure what else they could have done to guarantee the dam will get eaten away in our next several inch rain, likely unseen by anyone, until I walk down one of my paths after the storm to discover the entire flood plain, exposed rock, moss covered trails, walking bridges, and likely trees will have all been swept away leaving a trail of destruction and debris and mud, all the way to the South Anna river. Could happen with the rains forecast this weekend.
I spoke to Andrew Fisher with the Va. Dept. of Forestry twice to day. He was most helpful twice today: first with his call this morning returning my message from late yesterday, supportive and concerned and into action with a visit to the property and again with a follow up call late today explaining his visit and his chat with the guys doing the cutting. After that call, seemed like the cutting along the creek was going to stop and they may not cut the small triangle of land across the creek. After his second call, I wandered with a large brown dog over the check out the days work, that was when I really looked at what they had done to the spillway - a spillway, working perfectly, that had water flowing away from the very full dam until late June. Now it was full of debris, a new dam ready to back up the next time we get a heavy rain forcing that runoff to quickly eat away at the back of the dam (it will take much less rain without the slowing and absorption of the now gone trees and heavily disturbed soil). It might handle a little shower but a 2-4" storm, and we've had several already this year, with the amazing cutting power of lots of running water, could take out the dam.
While it is not illegal in Louisa (of course not) to cut all the trees along a waterway, it is if that cutting leads to issues with erosion and sedimentation downstream. Apparently, you can cut 'em but if it leads to problems, then you have a problem. I will be calling Mr. Fisher tomorrow (I have to guess he didn't see the dammed spillway) and might give Taylor Burleson, with James River Forestry, a call, too. He had assured me when we spoke back in March they they would not cut along the creek or around the pond, so much for that assurance.
As mentioned earlier this week, the near calm of quake activity on Hawaii matches the slowing and near secession of the current eruption, ongoing for months now. Fuego, Guatemala's nightmare for months now is not even on the week's list but Etna is back and Krakatoa is still unsettled. Ambae on Vanuatu is belching big from a lake causing major evacuations from that archipelago. Earth's still rocking! Hope you neighbors are not working toward a major flood into your property as mine seem to be, Today on Earth.
And, happy first day of school Louisa (and others), glad I missed it.
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