An Off Grid Water Monitoring System

I got into Heli­um to deploy and use a LoRa Wide Area Net­work (you can read about that here). Along with every­one else, I then got caught up in the wild gold rush of ’20-’21, deploy­ing hotspots and earn­ing HNT, help­ing clients do the same, and occa­sion­al­ly just look­ing around and won­der­ing at the mad­ness of it all. While that was fun, and an incred­i­bly prof­itable excuse to get out into some of my favorite parts of the back­coun­try in San Diego, that run is over and I can final­ly return to the rea­son I found and start­ed with this project: Sensors.

As the VCs like to say, I have a the­sis. My the­sis is that wide­spread IoT deploy­ment will cre­ate a new source of wealth from the streams of phys­i­cal data these devices gen­er­ate. This seems obvi­ous: If you know more about the world than some­one else (the fan­cy term is “infor­ma­tion asym­me­try”) you can trade your infor­ma­tion for a mar­ket price.

Now, this idea isn’t new. Hav­ing infor­ma­tion asym­me­try is how busi­ness­es like Google and Face­book suc­ceed, how gov­ern­ments fight and win wars, and how gen­er­al­ly any­one suc­ceeds. When you know more, you can do more. 

What is dif­fer­ent here is that a new fun­da­men­tal struc­ture for col­lect­ing that infor­ma­tion has been built, is open to any­one, and is cheap to use. With almost a mil­lion Hotspots pro­vid­ing a gate­way onto the Heli­um Net­work (as of late Aug 2022), there is no short­age of entry points to get infor­ma­tion from where it is col­lect­ed into your hands.

The hur­dle at this point is two-fold. First, you’ve got to use your cre­ative mind to devel­op an idea for the prof­itable use of the infor­ma­tion col­lect­ed by sen­sors. The infor­ma­tion isn’t out there yet, just the frame­work for col­lect­ing it.

Sec­ond, you’ve got to have the tech­ni­cal abil­i­ty to deploy those sen­sors, gath­er their data, and turn it into some­thing use­ful. I’ve writ­ten about a very basic project before (how to get a sen­sor on the net­work), which is a great start. However…

The Net­work is in the process of chang­ing from that method to one that is more tra­di­tion­al. Now, the guts of that are pret­ty tech­ni­cal­ly com­plex but the upshot is not: With the move away from Heli­um Con­sole and onto Chirp­stack (or any LNS, which stands for LoRaWAN Net­work Serv­er), it’ll be eas­i­er and more reli­able to use the Heli­um Network.

Still, it ain’t iPhone sim­ple yet, and I’ve found the best way to under­stand how it works is to use it for a spe­cif­ic purpose.

In my case, I was giv­en the pur­pose by the usu­al pur­pose-giv­er in my life, my wife.

Get up”, the DM read. “Don’t ask ques­tions, don’t bar­gain, dri­ve up there right now and buy it. It’s a steal at this price.”

One of Lee’s Insta­gram bud­dies was blast­ing her on a Fri­day morn­ing about a foun­tain on Craigslist. Now, this was­n’t just any old foun­tain. This was a giant jagged con­crete ball and cup, an odd design that was unusu­al, but not flat-out weird. It’s the kind of thing you might see in front of a small town bank that sup­port­ed the arts. Tech­ni­cal­ly the style is called “Bru­tal­ist”.

The foun­tain was up in Los Ange­les, about a 2 hour dri­ve north from our place in San Diego. So, about 2 hours and 10 min­utes after we got the DM, we were pulling into the dri­ve­way of a gat­ed com­mu­ni­ty where the foun­tain was.

I can’t say the foun­tain was a hor­ror show, but it sure did­n’t look like the brochure. Fad­ed blue paint, foun­tain lights only half attached, a few cut wires, and the “indus­tri­al water pump” in the ad was just a $20 spe­cial off Ama­zon that, well, was­n’t that spe­cial. Still, I’ve always liked a good project, and this had “project” writ­ten all over it. We loaded it into my truck and drove back home.

Of course, nei­ther the ball nor the foun­tain are light or easy to move (they’re con­crete, though at least the ball is hol­low), so I enlist­ed the help of my neigh­bor Pete, and we got every­thing moved into the back­yard using his lit­tle roller cart.

I spent the next month or so grind­ing off the paint with a wire wheel in 15 minute efforts slipped in between con­sult­ing, writ­ing, State of the Net­work shows, and the rest of the GK life. 

With help from Seeed, I put togeth­er a bevy of sen­sors to use in what I began call­ing “The Foun­tain Project.” There’s a Liq­uid Lev­el Sen­sor, an Indus­tri­al EC and EDS Sen­sor, a Sense­CAP LoRaWAN Data Log­ger, a Soil Mois­ture, Tem­per­a­ture, and Humid­i­ty Sen­sor, plus a Dragi­no LT-2222‑L, the LDDS 20 Liq­uid Lev­el Sen­sor (back up and cross check), a Water Flow Meter Sen­sor, and for the hell of it, a Dis­solved Oxy­gen Sen­sor.

You see, I’ve seen a ton of dif­fer­ent requests come through for var­i­ous water data-col­lec­tion projects in Heli­um. Flash floods warn­ing sys­tems, mon­i­tor­ing water lev­els in stock tanks, track­ing water qual­i­ty in ponds, etc. I thought it’d be pret­ty cool to take what was a small refur­bish­ing project in my back­yard and turn it into a giant super-fun exam­ple of a data col­lec­tion machine.

I fig­ured we’d track every­thing we could think of to track, from water temp to tur­bid­i­ty, acid­i­ty to depth, flow to TDS (total dis­solved solids). As it turns out with water, there’s a lot to keep track of!

I reached out to local double‑E (that’s Elec­tri­cal Engi­neer) Dirk Beer at DB Tech to help design and build the sys­tem. I met Dirk through Heli­um, and saw right away that his knowl­edge and exper­tise would be crit­i­cal on a project of this com­plex­i­ty if I want­ed to fin­ish it in any kind of rea­son­able time frame. Dirk is an Applied Cog­ni­tive Sci­en­tist, which basi­cal­ly means he fig­ures out how to make sure you can use com­pli­cat­ed technology.

This def­i­nite­ly seems like that. After all, we’re com­bin­ing a bunch of sen­sors that aren’t yet user-friend­ly, send­ing that data through a grow­ing net­work that is mak­ing a major shift in how the data is processed, and then dis­play­ing it in a vari­ety of ways on tech­nol­o­gy that requires a fair amount of edu­ca­tion to set up.

So that’s the base­line; we get and dis­play the data. Pret­ty cool, but that ain’t the full val­ue-add. I’m super curi­ous about how we com­bine all the data we’re receiv­ing to under­stand new aspects of water mon­i­tor­ing, as well as tak­ing our “pri­vate” data stream and ref­er­enc­ing it against pub­licly avail­able data streams like weath­er, air qual­i­ty, or even water quality. 

This inter­sec­tion of pub­lic and pri­vate data streams hold promise as a rich vein of infor­ma­tion to mine, with lots of poten­tial asym­me­try options bub­bling up.

With all that in my dreams and the future, I still had work to do. So I asked my wife Lee to help. 🙂

I fin­ished up with grind­ing and paint­ing the foun­tain, (Lee helped with the paint­ing) replaced the pump, and got it working. 

For a while, it was beautiful.

Then, anoth­er wrin­kle popped up: Algae.

Yep, with plen­ty of sun, con­stant water, and lots of lit­tle crevices, it turns out the foun­tain is an algae grow­ing machine. This brings up an obvi­ous point: You can track all the data you want, but if the medi­um you’re track­ing in gets over­whelmed, well, you’re just track­ing mud­dy waters.

That means I had to build a fil­ter sys­tem in order to keep the water clean enough to mon­i­tor, and real­ly to have some­thing to mon­i­tor in the first place. Now, this may seem weird, but I dis­cov­ered a per­son­al obses­sion, almost a fetish, with design­ing a water fil­ter­ing sys­tem. There’s so much to do, and know, and it’s easy (and fun) to go over­board. I mean, phys­i­cal fil­ter­ing is one thing, but why stop at screens and sand when there’s UV light, ozone bub­bling, and pro­tein skimmers?

I start­ed off by dip­ping my toe in with a small $12 pump on Ama­zon and build­ing my own DIY PVC fil­ter, then send­ing the water out through a small (I thought it’d be a lot small­er) UV ster­il­iza­tion device. The pump was 12 VDC, which means I could use some of the off-grid com­po­nents I’d bought for Heli­um the year before to run it. I pulled out a 100 watt solar pan­el and the 50 Ah bat­tery along with a Vic­tron charge con­troller, hooked it all up, and ran it for a day or so.

The good news was that the solar pan­el was gen­er­at­ing enough ener­gy. The bad news was it was only 78% of rat­ed pow­er. The ugly news was that I’d prob­a­bly need more of every­thing to do the job I want­ed to do. 

It was a janky set up, I know. Still, I knew it was­n’t my final, it was my first, and I’d learn a bunch. I did.

First, even in a small water vol­ume like mine (less than 15 gal­lons), with the amount of sun the foun­tain gets and our balmy out­door temps, the pump was­n’t cir­cu­lat­ing enough water through the fil­ter & treat­ment sys­tem to keep the water clean. It was most­ly clear, but with a green­ish hue. Not accept­able for Lee, plus the tiny pump had a loud whine run­ning at high rpms.

Now, before you tell me to just add bleach every few days to kill the algae, I’ve got to tell ya: Bleach won’t fly with Lee. End of sto­ry. I know, I know. Bleach kills every­thing and will save me 40 hours and prob­a­bly a thou­sand or so dol­lars. See the above re. Lee. 

The sec­ond prob­lem is that there isn’t enough water move­ment. Sure, the pump was mov­ing water through the fil­ter, and the fil­ter was work­ing, but the prob­lem was that it was­n’t all the water in the tank, just some of it. In order to clean all the water you have to treat all the water. In order to treat all the water you have to move all the water past the pump, and an intake diam­e­ter small­er than my favorite pen just can’t cre­ate enough suc­tion to gen­er­ate tank-wide water movement.

Now, I’m sure even­tu­al­ly some aquar­i­um expert will come here and shake her head at my igno­rance in hop­ing my ini­tial plan would work, but hell, for a first attempt it was­n’t bad. 

For my sec­ond run, I decid­ed I’d go more towards the over­board side, with a much larg­er pump housed in an exter­nal struc­ture, ozone treat­ment on top of the UV light, mul­ti­ple phys­i­cal fil­ters, and includ­ing water move­ment through­out the foun­tain in the design. If I can swing it, I’ll add in a pro­tein skim­mer. I mean, at this point, why not?

I also want­ed to move all the machin­ery out of the foun­tain. The whole point of the thing is to add a lit­tle seren­i­ty into the back­yard, and tubes and pumps and fil­ters all jum­bled togeth­er next to it don’t real­ly add to the vibe we’re going for. Plus, I need­ed a roof big enough for the solar pan­els that’ll pro­vide the pow­er for all this. Mov­ing water ain’t energy-cheap.

Since I was going whole-hog, I fig­ured I’d add in a reser­voir to the pump­house where all the water treat­ment hap­pens, pulling in untreat­ed water from the foun­tain and return­ing clean water. 

For all that to work, I’m plan­ning on tak­ing the foun­tain apart, dry­ing it all out, drill a few new holes in the con­crete bowl for drainage and return (you know I love drill con­crete, right?), re-paint a col­or that makes algae less obvi­ous, and build a stand to let grav­i­ty do at least some of the work for me. Oh, and build a lit­tle home for my mega pump & fil­ter contraption.

So, that’s where we are now, at the end of Stage 2. Stage 1 was the pur­chase, prep, and ini­tial set­up. Stage 2 was adding in a sep­a­rate pump and fil­ter. Stage 3 will be build­ing out a more robust fil­ter and water move­ment sys­tem, and Stage 4 will be adding in sen­sors to the net­work in order to mon­i­tor whether or not the sys­tem is work­ing, and when it isn’t, what exact­ly is going wrong.

If you’d like to fol­low along with this and keep up with all the sen­sor deci­sions and learn­ings, the best way to get the most infor­ma­tion is to join the Gris­tle Crüe. The Crüe is a paid mem­ber­ship for folks seri­ous about learn­ing togeth­er. Think of it as a Mas­ter­mind for Blockchain & Meat­space projects, with Heli­um front and cen­ter. We meet once a week on Zoom for pre­sen­ta­tions by experts or dis­cus­sion amongst our­selves (includ­ing in Octo­ber our first Hot­seat ses­sion!) and have our own pri­vate Dis­cord to prob­lem solve quick­ly with fel­low experts. If you want to max­i­mize the whole blockchain & meat­space oppor­tu­ni­ty, join the Crüe.

If you think I’m bat­shit crazy OR you’re a water treat­ment guru and can see clear flaws in my think­ing, drop your com­ments below, and thanks in advance!


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