Pond Boss
Posted By: interplexr Remedy damage to emergency spillway - 11/12/20 01:15 AM
We just got walloped with over 3" of rain in the span of less than 2 hours on already saturated ground. I've never seen so much water run over my emergency overflow! When the water came down it looks like there was a little washout near the bottom of my overflow before it rejoins the stream. I just recently cut back some trees that were shading this section of the overflow so it would grow back up but to little to late. What would be the best way to deal with this washout? I could fill it back with dirt and reseed with grass and plant in sedges, rushes, and other natives with deep roots like I was starting to grow. My other thought was to dump some rip rap in and dirt and seed and also transplant a lot of sedges and rushes into the fresh soil and seed the rest. We don't get rain like this often but I want to make sure next time we get this much rain the overflow is prepared. I'm afraid given enough of these events, it'll slowly erode back up the slope where it will work its way back to the dam eventually if I don't do something now. Any suggestions would be appreciated!

The one picture is of the emergency overflow running. It was quite the flow. The other is the damage after the event. This is where the slope gets gentle in the area to the right of the white water in the running pic.

Attached picture Overflow Running.png
Attached picture Washout.png
Posted By: esshup Re: Remedy damage to emergency spillway - 11/13/20 11:27 AM
I like your plan #2 with the rip rap. You can also put an erosion mat down after you seeded it and cut through it to plant the plants.

There are 2 types of erosion mats. One type uses a plastic netting that will take a LONG time to break down. The 2nd type is made from all natural fibers (Jute) and will break down within a year or two.
Posted By: interplexr Re: Remedy damage to emergency spillway - 11/15/20 01:38 AM
Thanks esshup! I hadn’t thought of the mats. That would help especially since it’ll be next year before a lot of the seed would sprout giving it’s getting cold!
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