Pond Dam: Repair or Rebuild?

Curious if anyone has any insights or suggestions or perhaps something we aren’t considering on the topic.

The pond was already on the property when we purchased the land but was not properly constructed. The dam is too small for the pond and is eroding away. There’s 2 overflows which I assume the first was intentional and the 2nd created to address excess overflow.

My land is in zone 7 with about 40” of rainfall a year. My acreage is long and skinny, just 375’ wide. The west of the property has a watershed that runs East to our spring fed pond. On the immediate east side of the pond, a creek runs the length of the property.

The soil is heavy clay and the landscape is native grass with a 4% slope.

The watershed flows from our neighbor’s property into the pond which also needs to be addressed with culverts for our road which will run through. Also wondering if there’s a type of earthworks that can be done here to slow and spread the water.

I had a permaculture site assessment done and he suggested I slowly rebuild the eroded dam with hay bales and dirt a little each year.

I also got a 2nd opinion from NRCS who suggested I break the dam, let it dry for a year, and rebuild. His second suggestion was to break the dam and build a new dam down in the creek, further expanding the pond which we would need neighbor approval for. He provided engineered drawings.

I don’t really want the pond any larger and I don’t really want to break the dam either. Repairing is the preferred option - the challenge will be getting heavy equipment to cross over the overflow. We are considering adding a culvert to the second “emergency” overflow that was built and driving over it with equipment to access the eroding dam.

Thanks for your time!

It would be hard for me to break a "functioning" pond to rebuild it. Here is an alternate idea, since you seem to need a culvert anyway why not get some temporary pipes and siphon down the level of the pond a bit, then dig the "emergency" overflow down a bit so that when you place one (or more) large culverts (think 24"+) they would become the primary overflow. Pack the culverts in well with your clay soil before the water level rises back to the lip of the culvert. That way your primary overflow would not have a chance to erode the dam, as it would be passing through the dam in a plastic pipe.

Best of luck with your project!

John Young wrote:It would be hard for me to break a "functioning" pond to rebuild it. Here is an alternate idea, since you seem to need a culvert anyway why not get some temporary pipes and siphon down the level of the pond a bit, then dig the "emergency" overflow down a bit so that when you place one (or more) large culverts (think 24"+) they would become the primary overflow. Pack the culverts in well with your clay soil before the water level rises back to the lip of the culvert. That way your primary overflow would not have a chance to erode the dam, as it would be passing through the dam in a plastic pipe.

Best of luck with your project!

Thank you for your reply! Adding a culvert sounds like the best route and I agree, would hate to break the pond. I’ll try to update the thread as we progress.

Our second challenge is road placement given the watershed. We are now considering building the road on the east of the tree line, closer to the pond mainly because it would save costs (less culverts, less gravel). This spot is lower in elevation so we would have to add dirt here to build the road up. Directing this running water towards the pond as nature is already doing is probably the best design, I just wasn’t sure if there were a better way to slow and spread the water across the land.