Pond Boss Forums POND CONSTRUCTION Building a dam What does "core the dam" mean?

I read a post below about whether or not it is necessary to always "core the dam." Can someone explain what that means?

THANKS!

Hi Okie Writer, welcome to the forum. You may not get many responses to your question because it's just too basic. I recommend doing some reading on the subject. If you're planning on building a pond you should get Bob Lusk's book "Perfect Pond... Want One?". I don't see a link for it yet, but you could call the phone number from the PB main page.

Too BASIC?

Thanks...

O-W,
This is one of the staples from a collection: core stuff

Good morning Okie Writer.

Let me make an attempt to answer your question. Some also refer to the core as the keyway. One of the main reasons for the core is to provide a seal between virgin soil and the dam to prevent leaks. Numerous posts have discussed dam cores but here is one from Brettski that shows a dozer cutting the core.
http://www.pondboss.com/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic;f=2;t=000108

Hopefully this will help address your question. A search on the topic should also yield more answers.

Thanks B-ski. You can peck faster than I.

I was wrong. Again.

Nope. If you're building a pond, you should have that book.

Two rules of thought on why you core a dam that I've come up with.

First, it stops the path of water from traveling under the dam. When you put new soil on top of existing soil, you have a layer between the two soils that is not a 100% seal. In time, this can lead to water working it's way through the dam along this line. The core creates a barrier that stops this path.

Second, it locks the dam into place. The water in the pond has allot of weight and presure pushing outwards. If the dam was just dirt piled up, it wouldn't be able to withstand the force of the water and could either move, or break. The dam needs a certain amount of weight to counter the weight of the water. Creating the proper slopes helps to distribute this force, but you still need the mass of the dam to be suficiant to hold back the water. By coring the dam, you are makeing it heavier and bigger. The same is true for how high above water level you build up the dam. Depending on how tall the dam is, you need a certain width, height and depth to it in order to it to be permanent. Soild types are also very important to this formula.

Eddie

VERY good info! Thank you all! You, too, GW. As a former moderator at another site, I should have known to do a search before asking.

Thanks again ~

No problem Okie Writer, thanks for mentioning it.