This.

And not to pontificate, but if you've not run heavy equipment before I wouldn't start with a project like this. Cutting slopes to a specific profile isn't easy. And while if you have some time under your belt running an excavator becomes second nature, starting with a decent size machine isn't optimal, as you can make enough mistakes that require time to undo that it quickly become a rabbit hole.

I learned fairly young and have run some really big stuff but I had supervision initially.
You'd be shocked how big of a mess you can make with say a d9 Cat dozer if you're not sufficiently experienced.

It takes years and years of running a piece of equipment all day, every day, to get good enough for me to hire a person to do work for me.

My brother once bought a bulldozer to play with on some land he owned. Didn’t last long.

I did a couple of creek sediment mitigation projects while working for a bay area city with soils engineering oversite for design & construction. Even though it had always handled storm run-off from storm drain systems with hardly any natural water sources Cal Fish & Game considered it a "natural waterway" so they had to be consulted during design and stopped in once a week or so to snoop around during construction. CF&G required that willow shoots had to be planted on the slopes even though we did no slope work to create a more natural habitat. The willows had to be irrigated to get established and since this was adjacent to an old, unimproved railroad ROW there was no water source available. The city had to jump through hoops, run nearly a mile of irrigation line from a city park, well a mile away....

This particular channel ran full to the brim and hard during heavy rains that used to run & perk down from the hills very slowly. but with all the pavement and hard scape the water was now dumping into the channel at a much higher, faster rate than when established years before prior to the development. The 1st big winter storm washed all the willow shoots to the next city down, along with all of the drip irrigation to get said willows established. CF&G did not give 2 *****s about that and the city was required to reestablish the irrigation and willow planting only to again be wash away the next winter.... The silt removal ended up being one of the cheaper aspects of the job even having to dam the channel up and pump the water around the work area during the summer working months. Not natural creek water, but irrigation run off from residents and a couple business parks.

I'm seeing a job that could easily be done with a smaller machine by an individual willing to put in the time to do the job. It looks like no more than a weekend project to me based on having done a job like this recently with a 12,000 lb machine. But I didn't rock the slopes, I grassed them.

Don't get me wrong, I have no problem with the size of the machine you're talking about. But for a homeowner?? Not a snowball's chance in hell I'd put them on that rig.

All I know is, at 3 o’clock in the morning, three sheets to the wind, if you drive a dozer towards a vertical wall, it will end up on its back. Speaking for a friend…..

I’m not suggesting he run it. We are in 100% agreement there.

Whatever you use it will be fun.

And even more fun would be to make a big pond while you're at it. You could have it as a swimming place during the summer and have fish and turtles in there.

I had erosion at my waterfront from heavy waves. Although it was only 25ft wide it was slowing eroding into the lake.
Needed a permit (do you?) and had to hire a landscape engineer and it had to approved by a local conversation authority.
Ended up we need boulders along the water edge and plants above it. Used native plants that had deep roots.
What started as a small project ended up costing me almost 10 grand. (we had them level the property and other stuff)

My point is get expert advice from erosion experts and expect open up your wallet.

Yeah, that was the plan. Make the existing "pond" bigger (about double the size which is still not big). When the weather is wet enough for it to hold water for a long time, we have little fish, frogs, snakes, and crayfish for sure. I don't think I've ever seen a turtle.
We would like to keep the water too.

And the guy's explanation on why the "pond" would be better if it was filled in doesn't really make sense to me. I don't think there's any reason why we can't keep the water.

It's not like the end of the pond is getting longer due to erosion. It's that there's erosion in another spot.

We'll get the Farm Service folks or someone out to see what they say.

I don't think we require an engineer or permit, or at least, no one would care/check if we didn't have one.

But yeah, the next step is to get different advice than the advice that we've already received. I was thinking that the folks that we spoke to would be knowledgeable (and I'm sure they are), but I think we were asking a couple of guys what to do with our screw and those two guys were standing there holding a hammer so we got the answer "you should pound it with this hammer."

Exactly. They have no clue what should be done. All this endless discussion of what equipment to use is way too premature. Figure out the solution, first. Recognize that the water flow is occasional/seasonal, which makes a difference in what you might do.