Posted tagged ‘spillway’

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September 2, 2020

I received a call from the man working on my washing-out spillway that he and his crew were down there last week getting some of the work done. My goal has been to refill the washed out area and then lay a concrete slab over the same to prevent it from ever eroding again.

He said he got about half of the work done and that maybe I didn’t want the other have done.

I’m no concrete expert. Nor can I read a forest to understand how water flows across it. I don’t have years of experience doing the kind of thing I asked this man to do. He suggested we meet at the cabin so he could show me in situ what needed to be done. I said I would be out there on Saturday and would stay until 5:00 p.m. to wait for his visit. (His son had PeeWee football that day, and I suggested the boy’s game had priority over my spillway.)

Rain was falling when we left the house in faraway suburbia Saturday morning, and it rained nearly the entire drive down. When we got to the turn off from the paved road, we had outrun the rain, but while we could still get a signal on our phones, my wife checked the weather map and saw that another huge system was approaching. By the time we drove two miles over the rutted, axle-snapping gravel road to my humble cabin, the rain had caught up with us.

This was fine. It meant I didn’t have to do any of my usual chores, like cutting firewood, cleaning up fallen limbs around the cabin, go looking for snatched marbles, or sling gravel. I could just sit on the porch and watch the rain, which I did. I updated my visit journal. I wrote a letter to a friend. We ate our pieces of fruit for lunch. We watch four ducks (gadwalls?) on the lake, oblivious to the torrents. We talked about this and that. And we waited for the dam man to arrive.

Eventually I decided there was one chore I could undertake. You may recall from my last post that something has chewed a few holes in the ceiling insulation just above the table. Here is a picture of the scene of the crime that I took on Saturday:

I had only noticed this because there were tiny silver shavings on the rug below. That was on the prior visit, and I brought a step ladder on this visit so I could do the repairs.

There were a few more shavings on the rug this time, but nothing substantial. I sprayed the holes with an insecticide, wiped the area clean, then applied a five-inch length of metallic tape over the holes:

I don’t know who the culprits are or if the insecticide will matter to them. I suspect they’ll not chew through this tape, but if they’re still up there, they may chew through another area.

And so I got one chore done. When the rain lessened a bit, I crept through the trees (for what protection they could give me from the rain) down toward the spillway. The repairs were done as the dam man told me, including a bit of on-the-spot engineering. His thought is that the erosion is really being caused, not by lake water rising high enuf to go into the spillway, but by water coming down my road from the ridge to the north and coming into the spillway at a right angle. He said it was likely that this right-angle water would undermine any slab that was there and cause an even bigger (and more expensive) mess.

We do have huge volumes of water come down the road. There is a ditch beside it that can handle the normal flows, but there are often great wads of leaves in the road beside the ditch that have washed out of it because the water went over its banks. The ditch turns away from the lake when it gets nearer to the cabin, but if the volume is great enuf, it ignores that turn, washes over the road, and heads down to the spillway. I’ve dug out the ditch at this turn a couple of times, but it fills with sediment and rocks quickly. I think raising the road at this point might help, but even that won’t always be enuf.

So the on-the-spot engineering the dam man did was to build a berm in the spillway just where the road water would enter it, steering the water into the rocky part of the spillway (rather than across the part with soil that may some day have a protective carpet of grass on it).

Although it rained the entire time we were at the cabin, the flow in that ditch was never more than a trickle because the ground was so dry from a few weeks of drought. The ground was absorbing most of the rain. Had it been otherwise, we might have been able to see the torrent coming down the road ditch (we’ve only seen the evidence of it) and what would happen when it reached the berm in the spillway. But that much water would be scary. The cabin is snug and dry, but getting through the two miles of gravel road to the pavement involves crossing three wet-weather creeks. So if there were enuf rain to overwhelm the roadside ditch by the cabin, we probably would not want to be at the cabin anyway.

The hours passed. The ducks passed on the lake below. We waited. I imagined that the rain would have cancelled the football game and that the dam man would be out earlier, but that didn’t happen. In fact, by 4:45 when we were packing up to go, he still hadn’t arrived.

As we were driving out, the rain stopped. The clouds parted. The sun came out. And the dam man never showed.