Please tell me pros and cons of mound septic systems

[KindredSpirit]

We are about to have a septic system installed on property we are buying. Because of the rocky area near where the system needs installed, they are suggesting a mound septic system. Please tell me the pros and cons of this. We are in Kansas, where the winters get pretty cold, do the lines freeze up more easily than with a regular system. Thanks for any responses!!! :baby04:

[Macybaby]

We had one in WI (only lived there four years) and never had any freezing problems. I would think winters in WI get a bit colder than Kansas. They were very common in that area (lots of lime stone). We didn't have a choice, was mound or don't build there.

Two reasons folks didn't like mounds, - they were visible, and they cost a lot more. The later was the main reason people did not like having to put them in. Never heard of anyone having problems, and they were very common in that area.

Cathy

[KindredSpirit]

Originally Posted by Macybaby

We had one in WI (only lived there four years) and never had any freezing problems. I would think winters in WI get a bit colder than Kansas. They were very common in that area (lots of lime stone). We didn't have a choice, was mound or don't build there.

Two reasons folks didn't like mounds, - they were visible, and they cost a lot more. The later was the main reason people did not like having to put them in. Never heard of anyone having problems, and they were very common in that area.

Cathy

Thanks for your quick response Cathy. What are we talking about in terms of cost, about twice that of a regular system? I am clueless in Kansas!!

[watcher]

The pro is if you get tons of rain the system still works. With our old system when there were several days of heavy rain it seemed the drain/leech system would work in reverse and fill the tank. When you'd drain water you could hear gurgling in several of the other drains.

The cons are:

The initial cost.

The fact the mound takes up land space. I could almost raise garden big enough to feed us on the space our mound is taking up.

It has a pump. Which means you have to have electricity for it to work. If there is a power outage you have a limited amount of usage. This also means you have something else to go wrong. And you most likely won't know the pump is out until you see "seepage" around the tank. Its not that difficult to replace the pump but it can be a bit nasty.

[bowdonkey]

Watcher is right on. I had to put in a super mound,{county law} looks like a small ski hill. Do a regular system if possible.

[Cabin Fever]

Generally, wherever a mound is "recommeded" it is in reality "required." I've never heard of a landowner being given the choice of mound or trench.

Mounds are typically required in the following situations:
1. High watertable
2. High bedrock
3. Clay soils (ie, slow percolation rates)
4. Excessively coarse soils (ie, sand and gravel)

[KindredSpirit]

Originally Posted by Cabin Fever

Generally, wherever a mound is "recommeded" it is in reality "required." I've never heard of a landowner being given the choice of mound or trench.

Mounds are typically required in the following situations:
1. High watertable
2. High bedrock
3. Clay soils (ie, slow percolation rates)
4. Excessively coarse soils (ie, sand and gravel)

The area they are looking at is right behind the house, which sits on a rock shelf. If they would go down the hill a little ways, the rock ends. I am trying to get them to do a regular system by going down the hill. Not sure, as a buyer, if we get much say, although we will be paying half if the sale goes through.

[KindredSpirit]

Originally Posted by watcher

The pro is if you get tons of rain the system still works. With our old system when there were several days of heavy rain it seemed the drain/leech system would work in reverse and fill the tank. When you'd drain water you could hear gurgling in several of the other drains.

The cons are:

The initial cost.

The fact the mound takes up land space. I could almost raise garden big enough to feed us on the space our mound is taking up.

It has a pump. Which means you have to have electricity for it to work. If there is a power outage you have a limited amount of usage. This also means you have something else to go wrong. And you most likely won't know the pump is out until you see "seepage" around the tank. Its not that difficult to replace the pump but it can be a bit nasty.

I had heard of the area it takes up, but I had no idea about the pump. Thanks for that info..

[Cabin Fever]

Originally Posted by KindredSpirit

The area they are looking at is right behind the house, which sits on a rock shelf. If they would go down the hill a little ways, the rock ends. I am trying to get them to do a regular system by going down the hill. Not sure, as a buyer, if we get much say, although we will be paying half if the sale goes through.

If the soils/site down the hill is acceptable for a trench system, I'd go for it in a heartbeat. With this landscape position, you might even get by with an all gravity (read: no electricty) system.

In our area of Minnesota, a gravity-flow trench system is about 4 grand. A mound system is somewhere between 10 and 15 grand.

Good luck!

[Pink_Carnation]

Well our mound has been a pain but at least it doesn't look much like one. Our property is sloped and they built it in a way that we could have a flat area around 3 sides of it. No electricity is a problem but we don't use much water then since our hot water is electric too.

[Chinquapin]

I have a 2BR mound system that I had put in about 10 years ago for around $10k. Be sure to get a good pump. My first pump lasted 9 years. The replacement pump (supposedly far superior to the original) failed in one year, as soon as its warranty expired. The third pump with installation cost $650.

In my system, the pump is wired to a very loud alarm in the house. If the pump stops working, I know about it immediately.

You might also ask your septic installers to give you guidelines on what should and shouldn't go into the septic system, which will help keep your pump as well as your mound happy.

A mound needs to have plants on it. You might ask the mound installers if they plan to spread grass seed on your mound. Mine did that without asking, when I had been planning to plant lower maintenance plants so I wouldn't have to mow. The mound designer suggested several native plants that would have fit right into my woods.

[KindredSpirit]

Originally Posted by Chinquapin

I have a 2BR mound system that I had put in about 10 years ago for around $10k. Be sure to get a good pump. My first pump lasted 9 years. The replacement pump (supposedly far superior to the original) failed in one year, as soon as its warranty expired. The third pump with installation cost $650.

In my system, the pump is wired to a very loud alarm in the house. If the pump stops working, I know about it immediately.

You might also ask your septic installers to give you guidelines on what should and shouldn't go into the septic system, which will help keep your pump as well as your mound happy.

A mound needs to have plants on it. You might ask the mound installers if they plan to spread grass seed on your mound. Mine did that without asking, when I had been planning to plant lower maintenance plants so I wouldn't have to mow. The mound designer suggested several native plants that would have fit right into my woods.

Thank you, very good information. Did you have to ask to have the alarm installed, or was that included as part of the installation?

[KindredSpirit]

Originally Posted by Pink_Carnation

Well our mound has been a pain but at least it doesn't look much like one. Our property is sloped and they built it in a way that we could have a flat area around 3 sides of it. No electricity is a problem but we don't use much water then since our hot water is electric too.

When you say it is a pain, do you mean it has been a lot of problems? Can you tell me in what way, so I know what to look out for? Thanks!

[KindredSpirit]

Originally Posted by Cabin Fever

If the soils/site down the hill is acceptable for a trench system, I'd go for it in a heartbeat. With this landscape position, you might even get by with an all gravity (read: no electricty) system.

In our area of Minnesota, a gravity-flow trench system is about 4 grand. A mound system is somewhere between 10 and 15 grand.

Good luck!

That is very interesting, I have never heard of a gravity flow system. I will definitely ask about that. Thanks!

[anniew]

My system was built with a 10 acres exemption from permitting. Nevertheless, a sand mound was put in, but there is no pump...it is all gravity feed...so still works when electric goes out as long as I have water.

[Darren]

Depending on the mound location's elevation compared to your septic tank, you may not need a pump. Another similar option is a peat bed system which doesn't use the leach field usually associated with septic tanks. You still have a mound with the tops of the peat bed modules showing.

[Pink_Carnation]

Well it has been a pain because of problems...last month 2 floats needed replacing in the pump tank several years before that we had to re-do the drainfield from damage before we bought the house the fix for selling didn't last. The alarm will sound if there is to much ground moisture because it can backflow into the tank. We are hoping the latest round of rain/snow didn't ruin it again but that is just because water flows through our property just under the surface of the ground. French drains can get overwhelmed and that means the water gets into the drainfield.

The tank has an alarm that they put outside...we are more likely to hear our neighbors and they hear ours.

[Phalynx]

Is the mound system the same as an aerobic system? I have never heard of the mound system, but we were required to but in an aerobic system where it had 3 chambers with pumps. you treat it with chlorine. It worked exactly like a real water treatment plant with the "cleaner water" flowing over to the next chamber until the cleanest water was sprayed via water pump to sprinklers in the yard in the night.

[Graystone]

We have one due to high ground water level. We are located on a canal and the water level is 3' down along our bulkhead. No basements here. I'll guess the ground level where the mound was built is maybe 4-5ft above the water level. The mound was built on top of that and measures 20ft wide x 50ft long x 1.5 ft high. The system is 10 years old and we have owned the house almost 5 years with no problems. Freezing is not an issue here.

[KindredSpirit]

Originally Posted by Graystone

We have one due to high ground water level. We are located on a canal and the water level is 3' down along our bulkhead. No basements here. I'll guess the ground level where the mound was built is maybe 4-5ft above the water level. The mound was built on top of that and measures 20ft wide x 50ft long x 1.5 ft high. The system is 10 years old and we have owned the house almost 5 years with no problems. Freezing is not an issue here.

Another question I had is about odor. Any problems with that. We know someone who has a system that smells.