Pond Boss Forums POND CONSTRUCTION Building a dam Emergency spillway design idea

I wanted to address fish migrating into my pond via the emergency spillway while it's flowing. I'm thinking about constructing steps or mini-dams just downstream in the e. spillway path. If the water flowed over one or two of these little waterfalls I think it would be much less likely that fish could swim into my pond. Unless they're salmon of course.

GW,
These mini dams would be past the end of the emergency spillway?
If they are in the emergency spillway they would add to the erosive effects of the water moving over it.

I hadn't thought about the exact location Kent. Any suggestions?

I was picturing two rows high of block filled with concrete for the dams. Maybe I would need to pour a slab on the downstream side to stop the erosion.

GW:
Just about any barrier downstream will stop the fish.
Otto

I need to stop Golden Shiners as well as Gams. What types of barriers will stop very small fish?

GW,

My uncle was having problems with GS entering his pond via the E-spillway(10' wide) in the spring during heavy rain. He had some large stone brought in to the site and installed a mini waterfall at the lower end of his E-spillway. There is approx a 18" drop now and that stopped all migration into the pond.

OK, I'll bite. I can see shutting out fish like carp & bullheads, but why are you targeting GS & Gams? I personally would like for them to swim into my pond in large numbers

The Shiners could be a problem because they get large and for now this is a trophy RES pond and RES are the largest predator.

Hopefully he only other fish in the pond for the next few years will be FH. I want to see if I can maintain a healthy population of them to provide a good forage base for the RES. My concern is that the Gams will prey too heavily on FH eggs and fry. At some point I may stock Gams to do exactly that as well as control the RES population, but I don't want that until the main fish get established.

Another reason I'm leery of Gams is that eventually I would like to stock this pond with a wide variety of local native fish. Gams dominate the shoreline so much that I would probably have difficulty establishing many other species. I read a post by one person who had a 3" pickerel in an aquarium with Gams for food. The Gams killed the pickerel.