Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Levee broke

Brent,
After you repair the levee again, you're not planning on cutting the emergency spillway into the levee are you? When my pond was put in, the excavator scraped out an area of virgin soil that slopes away from the dam that is at a level just below the top of the pipe going through the dam. This should prevent water from overtaking the pipe and flowing over the dam. After all, the dam is just fill, and subject to fail under the right conditions.

Good Luck
John

BrentD8, I know the feeling. My dam broke too but did not have it fix yet. I'm wondering if anybody knows what type of fish will escape if your levee broke. My levee broke just above the level of the drain pipe so the water level stayed the same. I'm worried when it rains and the water drain by broken levee. I hope the weather gets better and have your levee fix asap. hang in there.

bman

Brettski & esshup - One thing that has not been mentioned in this thread is that we are not the current owners of this pond. We oversee it for a close friend of my father's who lives out of state. That is why I am not overly concerend with the pipe being steel, although I do realize the reasons and the importance for a plastic pipe.

JMC - No, we are not gonna cut the emergency into the levee, the plan is to use the 8" pipe I currently have so serve as the emergency spillway, and build freeboard above that.

bman - Bad feeling to have ain't it? There were some that got out when it let go no doubt, but this repair was from a previous break and we have caught 3 bass 7 plus pound range this year so I think it will rebound nicely when repaired if history is any indicator.

Please rethink your E-spillway plan. If you are taking on enough water to fill a correctly sized principal spillway pipe, your E-spillway plan should be ready for Armageddon. 8" dia pipe is a questionable defense.
The best E-spillways allow the water to run over the top of the pond bank at at area that is not directly part of the dam mass. It is often very near the dam at a place where volumes of water can overtop a specific zone of groomed bank. It is often an area in the embankment where the top is lowered by a foot or two and fairly wide at this lower level; maybe 10 - 20 feet or more, depending on the inflow/outflow math. It's elevation is usually set slightly above the top of the primary spillway. The idea is to load the primary spillway and let it function at full capacity, and then some. This is why an anti-vortex baffle or hooded inlet are required at the primary spillway...to eliminate the whirlpool that will slow down the exit volume. The E-spillway would begin loading when the water elevation is about 6" higher than the top of the primary. Then, the top of the dam would be at least 1 foot (preferably 2 feet min) from the top of the water level of a fully loaded E-spillway.

What he said. If the primary spillway isn't enough to handle the water, then the 8" pipe won't do that much. With the climate seeming to be coming back into a wet cycle, I'd be planning for a 100 Yr. flood, and not a 25 year one. I think the 25 year flood has already happened and now we're working on a bigger flood!

My neighbor has lived here for 18 years, and this Spring was the wettest that he's ever seen. I remember wetter Springs, but I don't have any yardsticks to go by.

BrentD8, read Brettski's last over & over.
& put it in BEFORE repairs are made to the dam.