Aerobic Septic System Monitoring?

I am getting started on adding some monitoring and possibly control to my aerobic septic system. The main issue is to try and prevent damage when the backyard floods which is maybe one or two times a year. If it floods high enough it can backup into tank and flood the motors and UV system, which are pricey to replace. Few questions that maybe community can help me with as i get started:
-Initially, just going to add water sensor to the lowest septic riser and alert me if water is rising. Any suggestion for leak/water sensor that will handle being outside, in a septic tank riser where humidity is high? Don’t want it to die or have false alarm because the high humidity in the air.
-What is best way to connect to the alarm buzzer in the septic alarm box so i can use that going off to trigger smarthings alert?
-Have searched around and can’t find them, but are there z-wave circuit breakers? Would be awesome if they did since i could set system to cutoff power if water was detected in the riser.
-The system has a phone line from it that calls manufacturer if alarm goes off. This was annoying other day when it flooded since they assumed pump had broken and didnt understand flooding issue. In this case once the water went down and i reset system it was fine yet they still got alarm and came to house. Is there easy way i could include a zwave disconnect in the phone line so it doesnt call them if its just high water issue? If its real issue, once water goes down and it reconnects it would still call them.
-System has a small pushbutton switch on it to reset system. What is best zwave device i could use to remotely trigger that?

Any help would be greatly appreciated. Spent ton of money replacing the septic system this year and want to reduce as many expensive problems with it as i can.


  1. how much water rise? for 6+ inches, I like the big stupid tie-wrap float switches like Dayton “Tether Float Switch, Mechanical” Grainger Item # 6PNU4 Mfr. Model # 6PNU4 . They are rated for dirty water and I’ve never had one hang up. Humidity is irrelevant to this sealed switch.

  2. signaling from control panel, with relay coil wired parallel to buzzer, like Functional Devices RIBU1C-N4, driven by 24VAC/DC or 120v.

  3. disconnecting the company monitoring in any case, I would avoid. Also interrupting the pump operation by ST cloud is asking for trouble. Why give it a chance to not report, or not act when you really need it? What do you do differently, instead of pumping out by hardwired float switch, when it backs-up by rain?

The thing about manual resets is, it make you LOOK at the troubled system - that is a good thing. Systems fail in unpredictable ways, and direct observation is the most reliable monitoring method - you see, hear, feel and smell the system - most of those inputs are lost in remote monitoring. Automatic resets will automatically permit the eventual disaster.

  1. I’d monitor pump status by differential pressure status, seems like the best way for this (essential) purpose, and redundantly by current status too. Then any single sensor can fail and it won’t matter. Maybe you can also be notified by the septic phone call.

  2. The septic company doesn’t have any suggestion for rain operation? This situation is so unique?

My advice, monitor it all you like, but do not ever depend on something like this on such a critical system, it’s just going to end badly.

Thanks Eric. This is a unique situation in that its not just rain getting in there. The storm sewer that this system discharges too can’t handle all the rain during very heavy storms (last week we got 4 inches in just few hours) and water backups into yards and back through the effluent pipe into tank. If it gets high enough, which is only the extreme storms, it can fill the risers that extend up from the tank to the surface and this is where all the pumps, uv, etc are located. Topography of property and house didnt allow for much change in location to get it farther away from the water so this was best that could be done design-wise or county was going to make me do a much, much more expensive different style system. This was expensive enough.

-Instead of float switch i was thinking of maybe just going with something like the Aeotec Water Sensor, Z-Wave Flood & Leak Sensor since it has the probes on a cord and i could mount the transmitter to the inside top of the riser lids to help with signal and probes down at bottom of riser near top of tank. This way if the water comes up, I can at least get notified and if im home, run and turn power off to system so if it floods at least the power is off which should give better chance at pumps/uv surviving.
-for the alarm i can wire that relay up but any suggestion for what zwave device to connect it to? Seems like most of the zwave switches/relays are for triggering the relay, not the relay triggering the zwave. maybe im just misreading them but any suggestion would be appreciated.
-good points on the reset switch and monitoring. will check with them on seeing if it can call me also but i dont think it can. certainly didnt plan on relying on this monitoring as only means of defense but it certainly could help (could have easily saved the aerator pump the other day that was damaged if i knew hour sooner water was in that riser). Also looking into seeing if we can add backflow valve to effluent so we at least don’t get water backing up from storm sewer and we are doing little regrading of yard in spring that should help a little also.

Think for now based on comments so far it would be best i limit my upgrade to the system as additional monitoring and see how that goes. Thanks for your response.

agree with Benji - ST is best as a supplementary monitoring system for critical stuff.

For monitoring status contacts I have been preferring “Aeotec by Aeon Labs ZW097 Dry Contact Sensor, Small” - dry means “no external voltage” like the relay contacts - excellent battery life, but it does miss 1 out of 40-50 on or off events.

The Aeotec remote water sensor looks right if it will talk at your location.

if it was me with your equipment, if 120v pump, I would consider a plug-in smart-switch, like Zooz Zen 15 (up to 15 amps) . Make sure your pumps amps don’t exceed switch rating, note Zen is rated up to 0.5HP . If your pump IS 0.5HP or less then you get easy current monitoring also, which can tell you if the pump is healthy during operation. Just make sure there is NO automatic turn-off - any OFF-action is MANUAL by you, after you have been notified and you examine the conditions.

My experience, is for those plug devices that I have automatically issued ON and OFF commands, they have been subject to ghost commands (ON and OFF). For those devices that are ON-only, to monitor current like the fridge and washer, I have not been notified nor seen any ghost-OFF events. And I automatically repeat ON-commands for some triggers. My guess is the ghost-OFF events are temporary extreme latency/cloud problems.

good luck

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