Elevated Bog Pond

[dustboy]

Last summer I dug a big hole in the yard...I finally have figured out what to do with it.

My plan is to build this pond with an elevated bog. Lower pond will be 3-4' deep, ideally we would be able to wade in and cool off in the summer. Dimensions are approximately 8'x14'

The tree over it is an existing 12' Crepe Myrtle. This may be the biggest problem, it drops a lot of leaves in the fall and seems to drop a fine mist of sap. We may give it a year and tear it out if it's too messy.

The bog will require a bit of engineering to support the weight of the sand and water. It will flow into the pond via a wide weir. I had initially wanted a wide curtain of water but the energy required for such a pump is beyond what we are willing to spend.

I'm thinking I'll need a skimmer somewhere behind the bog at the pond level. Not sure what that should be. My local pond shop has been very helpful but he stacked up almost $3,000 of equipment including liner, that is certainly not going to fit our budget.

 

[Lisak1]

When you say "bog" and "sand" I get nervous. Gravel is the way to go in an engineered wetland bog. Sand will clog way too fast and you will just have water channeling it's way through without the benefit of filtration. I'm not sure what the engineering issue is - the bog will be in contact with the ground, correct? Or maybe you're concerned about the raised edges -

I'm not sure what you mean by a skimmer behind the bog - the skimmer should be in the pond. You want to be pumping water to your bog that's free of debris. This is going to be an up flow bog, correct? You skim the debris out of the water before it gets to the pump or you'll have problems with a clogging pump and probably a clogging bog.

As for your pump size - you really need to calculate the pond size and buy an appropriately sized pump. There are ways to create the look you're going for without oversizing your pump. I'm not sure where the energy use concerns are coming from, but if you can't afford (or choose not to afford) to run a pump that will turn your water over as often as required, then you're going to have water quality issues.

Just some initial thoughts! If I missed the boat, feel free to ignore!

 

[JBtheExplorer]

I use pea gravel in my bog. No clogs after five years, other than when I let some of the plant roots get out of control. Bogs are pretty cool. I'm so glad I went that route when I built my pond.

 

[dustboy]

Thanks, I will go forward with pea gravel, might have to do a little more bog research. Last thing I need is a cloggy bog!

What may not be clear in the rendering is that the bog is in a separate shallow box above the pond. The skimmer would be in the pond but obscured by the bog box. The bog box will need to have a strong floor since it will probably hold at least a ton of water and gravel.

Some of the calculations I’ve done show that a continuous curtain waterfall of this width would require upwards of 5-6,000 gph. Here in CA where electricity is expensive (and more so every year), this size of pump could add $75 or more per month to our bill. I will use a pump that is adequately sized to the pond, which is probably closer to 2,000 gph. I’m not currently planning to add fish, although we may decide to later.

 

[addy1]

That will look nice. You don't need a curtain of water, but it would look neat............

I have a bog waterfall where most of the water comes out, but the rest flows over the wall here and there. I love the sucker, never need to mess with water or water tests, it is always perfect. The size of it with all the plants takes care of the pond perfectly.

 

[MitchM]

If electricity consumption is a concern, have a look at some DC powered pumps.
They cost more up front but use less electricity than AC pumps.

 

[Lisak1]

You may find your bog plants struggle without fish to complete the ecosystem. Also remember that the most effective placement for the skimmer in a pond is opposite the waterfall as much as possible.

 

[addy1]

You may find your bog plants struggle without fish to complete the ecosystem.

ie poo and pee = fertilizer for the plants

 

[dustboy]

If electricity consumption is a concern, have a look at some DC powered pumps.
They cost more up front but use less electricity than AC pumps.

Please give an example? How would a DC pump run on AC grid power?

 

[MitchM]

DC pumps come with a built in inverter that converts AC to DC.
I would look at the Vectra series, which gives you up to 3100 gph at 130 watts.
https://ecotechmarine.com/products/vectra
These are not solids handling pumps, so use a prefilter/leaf basket on the intake.
They can be used as submerged or external.
There are less expensive DC pumps, usually made in China if you do a Google search for "pond DC pumps".
I've used DC pumps before, outside, with no problems. You're in a much milder climate than I am.

 

[dustboy]

Good tip, those are indeed efficient. Expensive yes, but energy savings would pay for the difference in a year or so. I like the variable flow too.

I wouldn’t mind adding a few lower maintenance fish to round out the ecosystem.

 

[addy1]

I wouldn’t mind adding a few lower maintenance fish to round out the ecosystem.

Fan tails stay small, breed slow and look neat. Low maintenance

 

[Spartamets]

Fan tails stay small, breed slow and look neat. Low maintenance

Fantails do stay small and look nice. However, I had two among my shubunkins, comets, orfe and koi. One got eaten by a heron (along with all the orfe and lots of others), and the other bred like a rabbit farm. Eventually the amorousness the other fish felt towards poor fanny got her killed last Spring (which was sad), but the fish population stabilized. We went from 15 to about 75 fish in one year (and probably more; couldn't count them all) because of that fantail. Now we're down to about 40 thanks to another heron and a rough start to Spring. No new fish this year without fanny. I'm going to get a new batch of orfe in the Spring. Those are fun fish, but heron magnets since they swim near he surface and can't keep still.

 

[ShawnInfirmity]

Your plan sounds pretty similar to my pond in the backyard except you have a hole which will allow you to do more with decking, etc. around the pond and bog. I'm looking forward to seeing how yours turns out!

 

[dustboy]

Progress...

Dropped a small pump/filter in there to keep the water moving until we get the bog set up.

Our apricot tree has clearly decided that SPRING IS HERE!!