Farm Irrigation project

I’m new to this forum, but know the value of having many ideas, and heads providing feedback and knowledge to a project.

My situation is that on the farm we have multiple water tanks and would like to set up water pressure sensors at each of them (7) 2 stations have 2 tanks next to each other while the others are stand-alone tanks.

Additionally, we would like to monitor our water usage using flow meters to gauge how much water is being used at any one time, if there are any leaks or breaks in the irrigation lines, are running too many outlets for the water being delivered through the pipes (night time we gravity feed, sunlight time our water lines are pressurized from our dam’s solar pump delivering water both to the irrigation network and to top-up the gravity feed tank that has a mechanical min/max float valve inside).

Some of these flow meters are sited at solenoid valve stations or next to tanks which we plan to monitor.

Recently I’ve installed a Home Assistant Server to monitor the solar controller to collect data, and provide feedback on how much power we are harvesting from our roof panels and plan to continue to build upon this later after water monitoring and control is taken care of.

I have some LoRa / LoRaWan equipment that I’m trying to integrate with Home Assistant (HA), and anticipate that will be the appropriate method of our devices spread out on the property in conjunction with using MQTT protocol.

I’ve got a few Arduino boards ie. D1 Mini’s, 8266, Mega, Uno and recently purchased an a Gravity throw-in type liquid level transmitter (KIT0139) to test with, plus an ESP32 board due to its extra capabilities including deep sleep between actions, and have some LoRa Hats too,

I can do the basics when it comes to programing (a long time since my Uni days), that is why I’m going to be offloading much of the logic to HA. So really just need to connect and forward data.

The bind that I am in is the hardware at present. In the past, I have purchased gear that basically sat on the shelf because it didn’t result in doing the job that needed to be done.

Over this coming month, I’m hoping to get 1 tank monitor going and relaying it back to a LoRaWan AP then directing the MQTT data to the HA Server’s MQTT Server before finally displaying it there.

Has anyone else worked/completed anything similar, I am hopeful I can learn from you to build my project and hopefully through my journey help others.


Welcome to the forum, David.
Here are a few posts found on this forum. I am not familiar with liquid level sensing, I am just good at keyword search. Hope these help you.


Hi David,


I’ve started on something similar recently, I tried to opt for a P-P connection since there arent too many gateways where I’m at.

I intent to use a LoPy4 as a kind of ‘Forwarder’ for LoRa (Not LoRaWAN) and ESP-NOW connections.

The MQTT forwarding part is complete but I haven’t found a way to get multiple network protocols working at the same time.

I’ve popped my code up on GitHub if you want to take a look at the beginnings: GitHub - LiamHowell/LoPy4-MQTT-Gateway: Trying to use a LoPy4 as a ESP-NOW and LoRa packet forwarder

I’m also curious what kind of hardware do you have so far?


Hi David.
What would your transmission distances be. I am not familiar with LoRa equipment so I had a bit of a look. Apparently it seems good for about 15kM out in the open. But also stipulates “line of sight” which each end must “see” the other end.
Now I don’t know what sort of terrain you have but starting with flat ground you would need a structure 7M high at each end just to overcome earth curvature even allowing for radio waves to bend slightly over the horizon so a profile of 4/3 earth radius is normally used when plotting a path profile. The 4/3 earth radius is allowed for when arriving at the figure of 7M. If you had a hill at each end that would help but as you are monitoring water tanks that is pretty unlikely.

Apparently the frequency used here is a bit over 900MHz. Be a bit careful here and try to always have “line of sight”. This frequency band (900 - 1000MHz) has a nasty trait of “scattering” over the horizon edge and you could get some funny results. In fact this characteristic is used to advantage sometimes as it is the frequency range used in Troposcatter point to point communication systems, mainly telephone. But with Telstra you are talking of kilowatts and very large antennas.

Many years ago I installed and commissioned such a system from Groote Eylandt to Gove which is 193kM over water. Transmitter power 10W each feeding into a parabolic dish 7M x 6M with a measured gain of 32db. The same at the other end. The dual dishes provided space diversity and different frequencies provided frequency diversity. There were 4 receivers at each end. 2 different frequencies on each antenna. Thus the whole system used both space and frequency diversity to obtain a clean useable signal. The system selected the best of the 4 received signals at any one time.
This is getting off track a bit but will give you some idea of different effects that can happen in different frequency bands.
Cheers Bob
EDIT: I think Satellites have killed off a lot of these systems but they were fun days.


Hey Bob,
Yeah being part of the Townsville Community Wireless Group back around 2000-2010 was a fun time with all those RIMS that stopped us from getting ADSL thus having us resort to making our own antennas or modifying old Austar grid packs - yeah those were the days - the good thing is that the lessons learned back then certainly provide for creative solutions to problems even today.

Most telemetry here is through a thick canopy of trees and or with various buildings dotted around the site. The longest distance would be around a Km maybe 2Km.
We have a Shed on the ridge and I plan to install the LoRAWAN AP at that location 900MHz. This while not being entirely central, does provide probably the best vantage point on the property as it is high, can send/receive both sides of the ridge, and potentially even allow us to mount a water height sensor at the bridge on the main road.

Once I get my Arduino LoRAWAN Sheilds sorted I’ll undertake some preliminary testing, its just a shame that I can’t get WiFi to the dam (lots of trees). Although I have yet to determine if I could use a passive repeater (2 antenna’s connected with a short pigtail (no power injection or signal boost) to reach it.


Hi Liam,
I mainly have ESP32 boards, some lower-end Arduino boards, and some LoRAWAN Sheilds.

I’m not much of a programmer, so grabbing help wherever I can, I also have a Duinotech LoRA & Wifi IoT Gateway XC-4394
I’m also using Home Assistant for much of the smarts enabling the hardware to deal with transmission and store/forward data through to Home Assistant.

I figured using a hardware IoT Gateway meant that I could have greater flexibility for mounting and powering - too bad the unit has such poor documentation and how-to.

1 Like

Hi David.

Yes, passive repeaters do work but there are a few things to consider.
The passive repeater has to be within about 400M of one end of the path. The reason is that at these frequencies most of your signal is lost in the first 400M due to “free space” path loss. For instance for 400M at 900MHz this is 83.5db and at 2.4GHz is 92db.
Each antenna gain has to be as high as possible because when you think about it this path loss happens twice, once from the end transmitter to the passive site and once again from the passive site to the receiver as the signal is re radiated and path calculations have to start again. This is the same for each direction. It does not matter which way around you are transmitting. So the antenna gains at the passive and each end have to overcome this loss as much as possible.

If you are a bit short on power and signal strength to start with this can get way out of hand and involve quite large and cumbersome antennas. I have had dealings with a few such systems. At 7GHz TV stations often use a reflective panel mounted on the transmitter tower to re direct the microwave signals down into the building and at Honeysuckle Creek during the Apollo moon missions 2 x 2M or 3M parabolic dishes ( I just forget which now) connected with a short length of wave guide were used to get the 7GHz signals around the corner to the tracking site. One at 900MHz at a site north of Wollongong was a bit of a disaster. The antennas were 2 arrays each of 4 quite large high gain Yagis installed on top of the escarpment, one pointing inland and the other pointing down to the control building on the coast. This worked fine except for a strong scatter signal (mentioned above) going in and out of phase with the wanted signal making the whole thing pretty useless. AWA engineers overcame this problem by making the repeater active without a frequency change. Pretty clever but I won’t go into details here but the solution was successful.

This is not meant to be doom and gloom but to point out some of the obscure pitfalls and hopefully preventing you connecting up a system believing it should work and then running in circles literally tearing your hair out when it doesn’t do as expected.
Cheers Bob