Septic Tank monitoring

[rickgd]

Hello all, First time poster here.

I have a new home that is in the final stages of construction. I have wired the snot out of the place (Im a network engineer) and I am in the process of implementing a moderate HA system using Girder/NR. Intially most of the HA will center around the AV systems and so on. As $$$ permits, I will be adding to it.

I am looking for a solution that would allow me to monitor the water level in my septic tank.
Commercial soultions are ok, as are DYI options. As always, the less $$ the better.

This is a new tank and drain field so now is the time to do this (I dont relish the thought of doing it later for obvious reasons). The septic system is designed to pump the waste to the drain field as it is quite some distance away and cannot be fed by gravity alone.


It would be great if it could somehow do the following.
Monitor Water levels
Monitor Sludge/Solids level and Sends an alert or notification to let me know that the tank needs pumping at a certain predefined level
The Monitoring device should be able to connect via either a hardwire or Wifi
Maybe monitor the pump status?
The ability to graph tank levels over time

Im not really knowledgable about the whole septic process so if there are any additional ideas on what to monitor, I would be happy to know about them.

Thanks again for any input

 

[roussell]

Welcome to Cocoontech! As for monitoring the septic tank, I think you'll know when it's full, at least I always have . Seriously though, look at industrial ultrasonic sensors. They're designed to monitor sludge, hazardous materials and such in tanks. A very good, but expensive one is the RS-232 Senix ToughSonic TS-30S1-SR232. It runs about $500 but is built like a tank and works great. I've used them at work for a while to monitor all sorts of nasty stuff.

A much cheaper route would be to use one of the Maxbotix sensors, there's a nice thread around here on them and I think they have an outdoor-ish version now. They won't be anywhere as durable as the Senix, and you'll have to fab your own housing, but they are about one-tenth the price of the Senix units.

Terry

 

[Lagerhead]

It's customary in my area to have a float switch in the lift tank. The float switch is typically wired to a simple in-house alarm, such as a buzzer of some sort. The switch closes when the tank level is high (much above normal), indicating a pump failure or some similar problem. In normal operation, the tank level is maintained within a set high-low range by the pump, and the alarm should never sound.

I took the float switch leads off the builder-supplied buzzer alarm unit and connected them to an Elk M1 zone, so this now provides my tark alarm. In turn, I am using the old buzzer alarm unit, connected to an M1 relay, as an additional alarm sounder in the basement.

I was able to test the float switch during the last septic tank cleaning, so I have reasonable confidence in this setup.

Of course a float switch does not measure the level; it simply signals when the level is too high.

 

[beelzerob]

I have the same setup you describe. I don't sweat the "water" level in the thing, but I monitor when the effluent pump comes on using a datanab current sensor. And then I (will) have a photoresistor over the warning light on the alarm box (top float) so i can detect when that goes off, though that's not much of an issue...you can hear the alarm quite well throughout the house.

 

[rickgd]

Thanks for the quick replies!

After reading through your suggestions and rethinking what is REALLY needed here, it sounds like making sure the pump keeps working will be the most important item. I will have to check if there is a float in the lift tank, I wasn't aware of that item and I may be able to use that to notify when/if the level gets to high and thus indicating a pump or similar failure. Measuring sludge/solid levels would certainly be useful and add to the "wow" factor, (lol Septic wow factor, who-da-thunk-it) but the 3-5 year cleanout schedule is probably all I will need.

I really like the Senix unit and it would certainly fit the bill, but its a bit out of my price range.


Thanks for the suggestions, they have all provided information I didn't have before, and will certainly help with the process. I will post back with results.

G

 

[beelzerob]

I'm amazed (if you don't) that you don't have an alarm float already. Granted, I think I only have one because the local septic enforcement office required one...but I would think it would be standard issue. It's pretty important to know if the tank is full!

 

[Lagerhead]

Just a few more miscellaneous points on this topic...

- There should be only clarified water in the lift tank and running out to the leach fields. Solids should be separated out within the septic tank proper, with the top water piped from the septic tank into the lift tank.

- If this is your first septic system, you should do some reading on what to avoid. Mistakes or carelessness can harm your system or seriously shorten its life.

- The M1 has a "vocabulary gap" in this department. Coming up with a meaningful emergency announcement using the existing vocabulary is a challenge.

 

[ipsgroup]

Hello all, First time poster here.

I have a new home that is in the final stages of construction. I have wired the snot out of the place (Im a network engineer) and I am in the process of implementing a moderate HA system using Girder/NR. Intially most of the HA will center around the AV systems and so on. As $$$ permits, I will be adding to it.

I am looking for a solution that would allow me to monitor the water level in my septic tank.
Commercial soultions are ok, as are DYI options. As always, the less $$ the better.

This is slightly off topic but I recommend you consider putting an effluent filter at the outlet of your septic tank before the effluent goes into the pump chamber. One of the main causes of septic system failure is solids getting into the lines in your drainfield -- especially with an LPD system like we installed. The effluent filter is relatively cheap insurance (<$200) against that.

We used a Zabel A300-8x18 filter installed according to the attached drawing (which I extracted from the design we submitted to the County for approval). At the time we built our septic system several years ago, filters like these were not required and my local Health Department folks were thrilled that we were going to install one -- it was the first one installed in the County. Because of this and several other elements of the design, the Health Department brought out all their inspectors on the day our engineer tested and certified the system to see, as the office director said, "How an LPD System should be built."

With all that money sunk in the ground, I wanted to make sure the septic was going to last as long as possible. One of the reasons I bring this up is that the Zabel filters have an Optional SmartFilter® switch and alarm that will warn you if the filter is getting clogged and your tank needs servicing. Since we bought ours, Zabel has been bought out by Polylok but the filter we used, as well as some others, is still available. Look here:

http://www.polylok.com/products_list.asp?p...subcat=Effluent Filters

 

[beelzerob]

Ya, ours has a filter too. It was an open debate at the time between our septic designer and the septic enforcement officer, but the SEO had the final say of course, which is fine with me, since it meant even more "protection".

Right now, about the only way to measure the health of my drain tank are to look at the time spent pumping (it's almost exactly 4:14 each time), and the time between pumps. I know if either of those start changing drastically, it could be a sign of a problem. Of course, the time-to-last-pump fluctuates quite a bit, and I'll probably notice more icky issues of a clogged filter before I would notice a problem with the times.

My plan had just been to have the filter cleaned when I have the main tank pumped, which is supposed to be every, what, 2-3 years?

 

[DrunkenLizard]

This reminds me that I need to make some changes to my septic system. I'm afraid part of the drainfield is to close to the surface (landscaper made some changes after I had everything graded properly when we widened the drive way. The other issue is when the previous owners built the house they for some reason put the lid for the septic tank a foot below ground level on a hill side (need to get an extension put on this). This causes two problems, First I have to get a shovel out and dig out the dirt that's built up over it whenever I need it serviced, and second when ever it rains and in the spring when the snow melts I get a large volume of water being added to the tank which in turn needs to be pumped to the lift station and etc. I'm sure it's not that big of an issue, though I would assume this will add up over the life of the system. Beelzerob, how are you monitoring the pump in your drain tank?

 

[beelzerob]

This causes two problems, First I have to get a shovel out and dig out the dirt that's built up over it whenever I need it serviced, and second when ever it rains and in the spring when the snow melts I get a large volume of water being added to the tank which in turn needs to be pumped to the lift station and etc. I'm sure it's not that big of an issue, though I would assume this will add up over the life of the system. Beelzerob, how are you monitoring the pump in your drain tank?

My holding tank is about 1ft below the surface, with a 1' plastic riser on the opening. But my ground is pretty flat.

You should probably build up some dirt around the opening so that water doesn't seep in. I'd be more concerned about the dirt being carried in than the additional water.

I've got two ways to monitor what goes on in the tank:

1) A current sensor on the pump wire. You could probably use any on/off type sensor, but I happened to have a datanab current sensor, so I get actual amp readings.

2) A photoresistor over the red "overflow" light on the alarm box. That box is tied into the 3rd float, which is I think 3 or so inches above the pump "drain" float. So if the pump fails to come on, the 3rd float rises and sets off the alarm.

Otherwise, that's really it. I would hope that looking at current usage over time (not that I have done this....) would reveal irregularities before the pump dies. I also plan (have still not done this) to add some logic to CQC to look at the pumping time and see if it is growing steadily longer, which to me would mean the pump isn't working as well as it used to. Like I said, it's usually a rock solid 4:12 pumping time currently. So if I suddenly start seeing times like 4:30+, that would probably be a reason to pop the tank lid and have a look inside.

 

[felixrosbergen]

ok..so now i'm worried...

My house was built by a developer and there were many items where decisions were needed and choices to be made. I hadn't really focussed on the septic much.

When you guys talk about 'lift' does this mean pumping? I know for sure my system is gravity based, there is no pump. I am not sure about a filter.

My tank is also partially in a hill, so one side is probably 1' underground and the other 3' or so. There is actually no marking of any sorts indicating where it is. The same builder put my neighours tank in a bit too shallow i think and you can see the outline of it in his grass...somehow the grass changes color right around the tank. I know where my tank is because i saw them put it in and because the snow melts around it just a tiny bit earlier than the rest of the lawn. I have have drawings should they be needed to locate it when it get's pumped.

We're only a family of 2 in a 4 bedroom house. Does this mean i can go longer between pumpings? I assume liquids (we take a lot of showers) don't really matter since they go into the field and the solids is all that matters.

 

[ipsgroup]

ok..so now i'm worried...
...
When you guys talk about 'lift' does this mean pumping? I know for sure my system is gravity based, there is no pump. I am not sure about a filter.

Yes, beelzerob and I are talking about systems with a separate dosing chamber containing a pump to send the liquid effluent into the drainfield periodically. Generally there are two reasons to use this type of design: (1) the topography of your lot makes it impossible to put the drainfield lower than the septic tank and/or (2) you need an engineered design that enables you to reduce the size of your drainfield by dosing it. In our case, it was for both reasons.

...

We're only a family of 2 in a 4 bedroom house. Does this mean i can go longer between pumpings?

Yes, this is usually true. You pump your septic tank to remove the accumulated sludge. But you should still have your tank inspected regularly to see how fast the sludge is accumulating. In Virginia, where we are located, the latest septic system rules require either an inspection port (a 4" PVC pipe from the top of the tank to the surface) so the sludge level can be easily checked without opening the tank or an effluent filter. I guess I'm a belt and suspenders guy -- we have both.

I assume liquids (we take a lot of showers) don't really matter since they go into the field and the solids is all that matters.

Actually, the amount of liquid introduced into the drainfield does matter. As I said in my earlier post, letting solids get into your drainfield is the #1 cause of failure but the amount of liquid introduced is also a factor. You want to avoid saturating the soil in your drainfield.

But with only two people in a 4 bedroom house, that is probably not a reason for concern unless you take really long showers. In Virginia, at least, septic systems are designed assuming two people per bedroom and 75 gallons per day per person. So in your case, the system should be designed to handle 8 people or about 600 gallons per day.

There is a pretty good explanation of how different septic systems work here:
http://www.septicsolutionstexas.com/Types.htm
and here:
http://pubs.ext.vt.edu/442/442-903/442-903.html

 

[rickgd]

So its been a while since I posted this topic originally. We actually got our final move in permit yesterday so as you can imagine i've been quite busy. With the various posts above I was able to ask my septic engineer to give me a run down on the configuration of my system.

As beelzerob thought, I do have an alarm float that will set off a (very) loud buzzer mounted outside the home indicating a high water level/pump failure. I also have a float that triggers the pump at a certain water level.

There is also a effulent filter in place to help prevent any solids from getting pumped to the leach field. which makes me happy.

The leach field is a pressure distribution system which means the 4 pipes in the field are all presurized equally by the pump and the wastewater is distributed evenly through the field.

So for HA, I'm thinking something very close to what beelzerob is doing which is to monitor the pump activity and alarm status.

Thanks again for all the information, it allowed me to ask intelligent questions and get the answers that were important to me, both in the HA area and in how the system works as a whole.