# pond overflow detection



## Flyingsod (Jul 11, 2013)

Got a fire water pond fed by a valve. Control of the valve to keep it at the proper level is all sussed and working.

What im looking for is a way to detect when the level gets too high and is about to overflow. We will get EPA fines if it makes it past the old settling ponds. So it will basically be a fail safe for when the primary control fails.

I would like it to be an actual liquid sensor of some type. Like two probes waiting to be immersed kind of thing. It'll be outside so rain can't be able to set it off. I wont trust a float for this. Well maybe a proper lift station type but the boss here is stuck on the floats that are on a cylinder and tend to get caught up on twigs or algae.

We have some probed level detectors that don't seem all that reliable. I'm unfamiliar with them though and maybe the ones here are just old or crappy.

I feel there is a standard industry practice for this but Im just not familiar with it. Any one know or have any ideas?


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## Jlarson (Jun 28, 2009)

Warrick probes with an AM series relay if you have AC power or a DC series if you have to go solar.


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## 460 Delta (May 9, 2018)

We use some B&W probe controls to maintain water level in water heater tanks. They read to ground to activate the relay, they are pretty much bulletproof for the R-Mix industry.


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## splatz (May 23, 2015)

I may be in the minority but I have a lot of confidence in two floats at the high-alert level and two at the high-alarm level. 



Wire the high alert floats so the NOs are in parallel and it will alert if either works, so unless they both fail at the same time, you're OK. Wire the NO's of the high alarms the same way. Interlock the valve by having its control go through all four NO's in series. 



This is real cheap even if you splurge on the top quality floats. Most will insist that something fancier is more reliable but I am skeptical, especially the day after a lighting storm. I have ponds and tanks on floats and pressure transducers and redundant floats have been solid. If I went with something more high tech, I'd still buy the floats for backup / redundancy.


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## gpop (May 14, 2018)

stilling well or for us poor people a 8 to 12" pvc pipe with holes drilled in it. Drive one end into the pond then mount the floats inside. Drill a few hole and place a piece of all-thread through the pipe at the top and use a 1" piece of pvc as a bushing so you have somewhere to tie the floats. Add a pipe cap to keep the rain and sun of the floats and also to stop weed growing inside the pipe (no sun light) This will work even if the pond is full of weeds, Lilly pads or high wave action caused by the wind. 

Reliability is based on good design and back-ups. Multiply floats, valves and controls wired fail safe may be the way to go.


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## joebanana (Dec 21, 2010)

Is that all the EPA has to do these days, monitor peoples pond levels? What about rainwater run off? Who do they fine for that? You?


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## paulengr (Oct 8, 2017)

I’ve seen the fancy stainless floats. They look fancy but they are so unreliable I have no idea who actually uses them. I think they are for pure liquids in pharmaceuticals. They have no business outside of clean conditions. Around here the sewage plants mostly have floats as backup but they are all going towards ultrasonics because they are reliable in that they don’t get clogged with condoms, tampons, so-called flushables, etc. if you insist on floats they mostly use the kind that has a weight internally that triggers when the thing tips on its side. You tie the cord off somewhere and it just loosely floats around. Hopefully it doesn’t get lodged somewhere. More than one is a really good idea for that reason. Floats are always trouble.

The best name in the business for ultrasonics is Hyde Park. They were bought by Schneider. Cost runs anywhere from $100-600. All they do is emit a pulse of high frequency sound and time how long it takes to bounce off a surface and echo back. It is sound based radar. Range is amazing, up to tens of feet but yuh risk heavy fog or rain if you push it too far. It’s usually 4 wires, 24 VDC. Two wires are power. Third is output sharing the negative with power. Fourth is a program input where you can use a shovel of something to set your limits. There are several variations, some with both digital and analog outputs. Very simple to use.


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## didntdoit (Jun 18, 2020)

Gonna double on ultra sonics. Put a set of controls together a couple years ago. Only issue for us was foaming, easily cured with a stilling tube. Shop for what you need they can be had with relays or 4-20mA when we got ours. Used the 4-20 style to increase process pump speed in our case.


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## Flyingsod (Jul 11, 2013)

joebanana said:


> Is that all the EPA has to do these days, monitor peoples pond levels? What about rainwater run off? Who do they fine for that? You?


It's not a garden pond with filtering flora and florescent fauna. It's an industrial fire pond. Thank ****ing god that someone is monitoring it or this company probably would let it run off into the stream to save a few bucks.


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## Flyingsod (Jul 11, 2013)

didntdoit said:


> Gonna double on ultra sonics. Put a set of controls together a couple years ago. Only issue for us was foaming, easily cured with a stilling tube. Shop for what you need they can be had with relays or 4-20mA when we got ours. Used the 4-20 style to increase process pump speed in our case.


 I tried like hell to convince them to go this route in the beginning. They went with cylinder floats in a glass jar. Silly really, we have these cheesy cheap ass floats controlling a 50+ grand system. Having all kinds of issues with em lately so maybe they will get changed.


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## Flyingsod (Jul 11, 2013)

Warrick, B&W, and Hyde park-Schneider. Thanks for that, ill be looking at their offerings.

Splatz, paulengr, I'm very familiar with those pear shaped floats. I've done tons of work in municipal sewage operations. I consider them pretty reliable, but less so in open outdoor water. Still, I'd use them and they'd be better than the glass jar things we have but for whatever reason the supervisor here doesn't like them. Imo those floats would be the best in the high alarm role. they may get hung up when they are floating around but there's little chance of that while they're just hanging. Also a little limited on what i can do. There's one input left on the SCADA and I wont be able to convince anyone to buy an expansion module.

The control of the pond is fine. (assuming the floats work) Even if i convince them to use an ultrasonic device for controlling pond level Id still like a more analog something that physically contacts the water for an overflow imminent alarm. Its the old school part of me, the same part that prints out my tax return even though its all on digital files.

Thankyou all for your help and input.


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## gpop (May 14, 2018)

Every sensor has pro's and con's or there would only be one type of sensor.

Insanity is doing the same thing over and over and expecting different results. 

Work out why its failing then work on the solution. If you honestly think you are the first person to face a certain problem you are probably kidding yourself. 

Simple things like "they may get hung up when they are floating around" have simple solutions. You know the problem is the floats are floating around so you need to try to control the cable when the float is active. 
Tie wrapping the float cables to a stainless steel cable that's anchored to a 20lb lump of metal, Adding weights to the float cable (they sell them), Keeping the float cable as short as possible, etc


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## didntdoit (Jun 18, 2020)

If you can put a estimate together present it - what does a fine cost in comparison? Money saving is more motivating to managers than making your life easier.


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## QMED (Sep 14, 2016)

In our factory we have the drexelbrook level sensors which are good. 
https://www.drexelbrook.com/products/point-level-measurement/rf-admittance-level-measurement/z-tron-iv-level-switch

How about pressure switches? We have 2 identical sumps for removing wash down water from the factory.

One sump is three float switches. They're always getting hung up though.

One sump is three diaphragm type pressure switches in a cabinet plumbed into a piece of tubing that goes down into the sump or well. 

We also have leak detectors for the generator cooling water. They are some kind of conductivity probes plumbed into drains to catch any leak water.


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## Flyingsod (Jul 11, 2013)

QMED said:


> In our factory we have the drexelbrook level sensors which are good.
> https://www.drexelbrook.com/products/point-level-measurement/rf-admittance-level-measurement/z-tron-iv-level-switch
> 
> How about pressure switches? We have 2 identical sumps for removing wash down water from the factory.
> ...


 the only experience with pressure switches is the air pressure ones on furnaces and paint booths. with no experience i gotta go by gut feeling and its seems an extra step that can fail. Namely the changing of liquid reading to air reading. maybe theres a one that stays in the liquid and directly translates lquid to electrical. Thanks ill look into that also.
That leak detector you describe was my original thinking. not sure now though as theres more options than i knew about.


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## Flyingsod (Jul 11, 2013)

didntdoit said:


> If you can put a estimate together present it - what does a fine cost in comparison? Money saving is more motivating to managers than making your life easier.


 That's a great idea. Ive learned to write business proposals using proper business formats and standard business jargon for just that reason. There's free templates on the net if you care to look. it works wonders speaking to them in their language.


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