Building a dam near Aspens

Hello fellow Permies,

I am in the planning stages of a small homestead, and have a spot picked out that I believe would be ideal for a small dam/pond, the only real issue being that it would border one side with a small quaking aspen grove.

The trees are just on the other side of the property line, so cutting them down is not an option; besides they are beautiful trees that provide lovely shade and improve the soundscape of the property immensely.

Knowing the growth habits of aspens, and seeing that the dam wall would be in such close proximity, is this idea at all feasible or would I be fighting a losing battle?

I am really hoping to avoid a pond liner, but any ideas/suggestions are gladly welcomed.

Thanks

Mark

Anyone...?

Hi Mark...Welcome to Permies...

Sorry for the delay...I was waiting to see if someone else from this side of Permies would answer first. I don't deal with ponds anymore one a daily bases like I use to (I owned trout ponds) but I have design and built quite a few.

For me to ever give educated views on something, I often need more info. This case is no different. For one, I would check with state law for your area. Constructing ponds on or near property lines is often got "rules" attached to them...mater of fact...messing with water in general has rules as it can become a really touching subject. Especially impoundments and water diversion/embedment of any kind.

So first check on that...next a complete photo spread of what you got and what you want to do...Then I can see and understand better the challenge and goals...

Sorry again for the delay...

j

Thanks for the reply Jay C.

As far as the restrictions go; I live in rural Newfoundland, Canada, there are very few regulations to speak of. That said, I am aware that there very likely is government guidelines in place for this sort of thing that I may have to follow, and I do plan on looking into them in more detail soon. Right now I am more concerned with figuring out if this is even worth pursuing realistically considering the issue of the Aspen trees.

The only photo I have of the area is sort of far off, but shows the aspens in the background and below is the area I where the proposed dam would be located. The feature I want to dam is basically a small gully/ drainage ditch; no running water most of the time, only in heavy rain.
In the picture the old fence line is pretty much woven in between the mature aspens. If you can make out the depression in the landscape just below this, this is where the dam would go, basically at the far left of the picture...

The pond will be mainly used as a small dipping pool for a sauna that will be built near its edge. I would ideally be able to run a sealed with a level sill spillway out just before the dam wall on the north side of the pond, but I have yet to do any contour measurements to know for sure if it will work...

Hopefully that's enough to go on. If you need any more info let me know.

Thanks for your help,

Mark

Sorry, writing this on a cell phone, the auto correct doesn't seem to know what a swale is I meant to write "run a swale with a level sill spillway..."

Hi Mark,

If you are going to look into the "rules and regs" I would at the same time see what assistance you can get in pond/wetlands construction. Many government extension agencies offer such guidance.

Do you plan on operating the heavy equipment yourself to build this or hire it out?

Regards,

j

I am open to information and guidance, but I prefer to involve the gov't in my life as little as possible.

I have a little experience with heavy equipment, but not much...I might hire out, or I may rent a small machine and get practice digging swales on the land and see how I feel from there. There are many people in the area who operate equipment, but dam building is not a common thing around here so I'm not sure I'd trust anyone to do it to the standards I'm looking for in a reasonable amount of time...

This is a project that is at least a few seasons off. There is much to be done first, but it would be nice to get the major earthworks done all at the same time...
The earthworks I have planned are a series of swales, a few terraces and some smaller hand-dug ponds besides the pond in question.

Do you have any advice on the trees?

How deep and how large do you want this pond to be? How high will the dam be above the toe of the slope? What kinds of soil do you have in the immediate area? Have you dug a test hole to the depth of the pond? If you have a reasonable proportion of clay in the soil and are not trying to make a pond that is too large for the potential runoff to replenish easily, you may need no liner, just proper grading technique. If there is a perennially wet area, your chances are better, unless there is a layer of gravel below that.
If the aspens are not far downslope from the pond, you don't need to worry about their roots except to keep the suckers mowed/pruned back so the grove doesn't spread farther than you want. It would be big roots in the actual dam that would be a problem, and the farther you spread out the downhill slope, the less you have to worry. Do you have a supply of rock/stone that you can line the downslope spillway with? It will obviously have a greater slope than the current stable flow, so will likely need reinforcement.

Glenn Hhavbert wrote:How deep and how large do you want this pond to be? How high will the dam be above the toe of the slope? What kinds of soil do you have in the immediate area? Have you dug a test hole to the depth of the pond? If you have a reasonable proportion of clay the soil and are not trying to make a pond that is too large for the potential runoff to replenish easily, you may need no liner, just proper grading technique. If there is a perennially wet area, your chances are better, unless there is a layer of gravel below that.
If the aspens are not far downslope from the pond, you don't need to worry about their roots except to keep the suckers mowed/pruned back so the grove doesn't spread farther than you want. It would be big roots in the actual dam that would be a problem, and the farther you spread out the downhill slope, the less you have to worry. Do you have a supply of rock/stone that you can line the downslope spillway with? It will obviously have a greater slope than the current stable flow, so will likely need reinforcement.

Thanks for the reply Glenn.

Would hope to have the pond deep enough to jump into and not bring up on the bottom, do anywhere from 6 to 10 feet at the deepest and shallower towards the shoreline. I haven't taken measurements yet regarding the area of the pond, would depend on where I place the dam wall. nothing overly large, just enough to get in an cool off after a sauna.
I would imagine the dam wall would end up being 8 to 10 feet high when it's all said and done.
The soil shouldn't be an issue, the area is mostly heavy clay; there were brick yards all over the place years ago. The area is wet all the time just under the surface of the soil...

Not sure what you mean by "the farther you spread out the downhill slope.."

Finding a supply of stone is not an issue, there is a reason the island is called "the rock"

I think Glenn has this covered for you questions, as he is asking the same I would...

As for the trees...well...they are not on your property and if you are not getting into the government rules I assume this project will ignore the rules for "easement setbacks" and property line boundaries as the apply to water impoundments...these are just the beginning rules a heavy equipment operator must (or should) follow when facilitating any kind of water feature...

So in general the tree may or may not survive depending on the set back and other features of the impoundment...it is really hard to tell at this stage of the plan...If you stay far enough back from the property line the root compaction shouldn't be an issue...

I will follow along as Glenn gives his good advice...

Regards,

j

"I think Glenn has this covered for you questions, as he is asking the same I would... 

As for the trees...well...they are not on your property and if you are not getting into the government rules I assume this project will ignore the rules for "easement setbacks" and property line boundaries as the apply to water impoundments...these are just the beginning rules a heavy equipment operator must (or should) follow when facilitating any kind of water feature... 

So in general the tree may or may not survive depending on the set back and other features of the impoundment...it is really hard to tell at this stage of the plan...If you stay far enough back from the property line the root compaction shouldn't be an issue... "

Thanks for your help Jay, I appreciate you taking the time to answer my questions

I think you misunderstood what I meant. I fully intend to go by whatever government regulations exist, I just would prefer not to involve them in things they need not be involved in...

It's not so much a question of the trees surviving; I would be sad if they got damaged and died, but somehow I doubt they would, with the root system they have I think they are pretty hardy.
The lot next door is abandoned and overgrown, I don't think anyone would notice or care if a few trees died. The main concern is the roots creeping into the dam wall and weakening it to the point of failure.

Mainly I'm just trying to get an idea if it is worth it to go through all the effort, or if the trees will just win in the end no matter what I do...

Open to any suggestions and tips on how to mitigate this issue.

Thanks again

Mark

An important factor in the dam building will be whether you want/need to be able to drain the pond completely in the future. If not, I would advise for both asthetics (looking natural) and safety/stability of the dam that you dig down as far as feasible, using the excavated soil to make a wide dam with the gentlest downhill slope possible. This will minimize the height of new slope that will have to hold up and make what new slope there is stronger. It sounds like you have a similar situation as most of the uplands around me: dig a hole and you will get a pond. Have you gone out with a shovel and dug the deepest pit you can by hand, to see what happens with water?