Welcome to EnviroDIY, a community for do-it-yourself environmental science and monitoring. EnviroDIY is part of WikiWatershed, an initiative of Stroud Water Research Center designed to help people advance knowledge and stewardship of fresh water.
New to EnviroDIY? Start here

Archive: Group Activity Updates

Community groups were turned off on February 3, 2020. This page serves an archive of all group activity updates from 2015 until the feature was turned off. An archive of member activity updates is also available.

Citizen Scientists Group

  • Tom Harten posted a new activity comment 2017-03-10 18:29:39
    I mis-named the webinar-it was the Model My Watershed. I understand that it will be archived for anyone interested.
  • Tom Harten posted an update 2017-03-10 18:26
    Really enjoyed the WikiWatershed toolkit webinar yesterday! Thank you Heather!! This is an awesome tool for educators as well as folks involved in watershed management.
  • Tom Harten posted an update 2017-03-08 18:06
    We do a number of citizen scientist programs with our students. I’d be interested in learning what others are doing in this arena. Thanks!

    • Heather Brooks posted a new activity comment 2017-03-08 18:41:31
      Welcome, Tom! Citizen science is a really exciting way to engage students. Did you know that EnviroDIY is part of the WikiWatershed toolkit? You might find additional tools there that you can use with your students: https://wikiwatershed.org/
    • Tom Harten posted a new activity comment 2017-03-08 18:48:50
      Thank you Heather! We are actually playing with that tool in the office right now! It’s a very interesting app that I think our students and teachers are going to really like. Just getting up to speed with the mechanics of it right now.
    • Heather Brooks posted a new activity comment 2017-03-08 18:56:00
      Great! I suppose you’ve already found the “WikiWatershed Toolkit for Educators” webinar recording on the videos page. 🙂 We’re also excited about the “Model My Watershed: A Tool for Water Resource Management” webinar being presented by US EPA tomorrow. It’s in the middle of the day, so not convenient for teachers, but we hope to be able to link to an archived version later.
    • Tom Harten posted a new activity comment 2017-03-08 19:08:57
      Thank you! I am going to register for this event. Wow! Great timing.

Data Logger Developer Group

        • Dimitris posted an update 2018-10-01 11:23
          Hi , I am coming from Greece/Europe. I would like to establish some monitoring stations here in my university (http://www.ntua.gr). I have tried to purchase the Mayfly but Amazon does not deliver this or the starter kit to Greece. Is there any thought for Mouser delivery channel? In case I cant find anyone to deliver the data logger to Greece, Is there any possibility of the schematics (Gerber files) of the PCB? along with the BOM?
        • Dave posted an update 2018-07-23 21:28
          Just an update on things from Dartmouth -On friday, we installed roughly 60 Acclima TDR sensors to monitor soil and dead wood moisture over time. We utilized 3 Mayflys in boxes, powered by lead-acid rechargable batteries and an RTC setup to do 30-minute collections. Installing this many sensors required us to utilize DIN rails instead of Grove ports and it was pretty easy to do. Questions, just let me know! Happy to chat! The next phase will be replicate plot networks and developing wireless network capability. Ideally we will use a radio mesh network approach, but that will take some testing. Some photos attached: 421_0-86851500-1532381294_img_0783.jpg

          • neilh posted a new activity comment 2018-07-25 23:22:03
            thanks for sharing. Interesting to see the pic. How are you charging the battery.
            It looks like you must have something like the TDR-315 and leave it on all the time.
        • Zaven posted an update 2018-07-19 19:58
          Hello, how might I get ahold of the EnviroDIY data logger hardware? There don’t seem to be any available on Amazon. Thanks!

        • GMU Flood Hazards Research Lab posted an update 2018-04-16 15:46
          Hello we are wondering if we could have some help with our code. Prior to going to the Mayfly development conference at Shenandoah University we were attempting to build our own data loggers. We were using Arduino Mega 2560’s, a ping sonar sensor, an RTC, and a Sim808 breakout board. We are able to generate time stamped data and we converted it into a simple string so we could collapse the data into the smallest piece of information available. The problem is when we send the data out using the Sim808 library the data being sent needs to be contained in quotes “datastring”. But when we put it in quotes it just sends out the text of the variable we are calling upon instead of sending out the data. Any help would be appreciated. We asked Shannon at the conference and she said to post the code on here to see if we could get some help.
      • Rick Vogel posted a new activity comment 2018-04-16 16:15:09
        data7 = String(‘ ” ‘ + data0 + data1 + data2 + data3 + data4 + data5 + data6 + data8 + ‘ ” ‘);for visual purposes I added a space between the single quotes and the double quote. you probably want to remove those extra spaces in the sketch
      • Rick Vogel posted a new activity comment 2018-04-16 16:21:15
        Can also do…..String quotes = String(34);
        data7 = String(quotes + data0 + data1 + data2 + data3 + data4 + data5 + data6 + data8 + quotes);
  • Guy McCarthy posted an update 2018-01-07 23:13
    The DS Mini is based on a PIC32MX150F128 processor, with 128K Flash and 32K RAM. The BLE transceiver is a RN4871 module, with the protocol stack in firmware. So processor memory is not much of an issue. The local storage is kind of cool; it’s an EMC1001 with 16K of static RAM. That allows fast access with minimal power consumption. Upon power-down, the entire contents of RAM is written to EEPROM in a single blast, powered by a capacitor. At power-up, RAM is re-loaded automatically.Since this is a low-end device, it doesn’t support professional sensors such as the SD1-12 type. Its intended to be cheap and easy to set up. On a smartphone you can scroll through a list of known sensor types, and a couple of taps will configure the data logger.I plan to use LoRaWAN on the mid-range and hi-end versions. In that case I’ll be using a RN2903 transceiver for long range wireless communication at 915 MHz, also with an internal protocol stack. It will be interesting to see what sort of range is possible close to the moist earth, or under a canopy as you suggested. I really appreciate your input on sensor types; since my background is in electronics and software, not environmental science.

  • Guy McCarthy posted an update 2018-01-07 22:57
    OK, here is another attempt to add the photo
  • Guy McCarthy posted an update 2018-01-06 20:48
    Thanks for the suggestions. Here’s a photo of the Data Station Mini, which accepts external sensors in the mikroBUS format (as in “Click” boards from MikroElektronika.) It’s based on a PIC32MX150 processor, with a digital temp sensor, EEPROM storage, and an efficient power circuit. There’s a AA battery holder on the back side. This is essentially a stand-alone data recorder, configured by smartphone, that stores data for retrieval at a later date.Current plan is to launch the DS Mini at crowdsupply.com in February. The other product I mentioned is an Arduino-style “shield” (expansion board.) It has a LoRaWAN (long range wireless) radio on board, and accepts external Grove sensors. It’s designed to work with any microcontroller base board in the Uno format, (3V or 5V.) These products are open-source, and programmable in Arduino IDE, PlatformIO, and MPLAB X. Cheers

    • neilh posted a new activity comment 2018-01-07 19:12:10
      Hey thanks for the details. There doesn’t seem to be any picture attached.
      Just wondering what is the full version of the PIC32MX150 – how much ram and flash.
      I’m guessing a bit, but seems to me for networking with LoRaWaN the issue is how to gateway to a TCP/IP centric world. Of course Rome wasn’t built with one project either …. :)FYI, my interest is for a 12V sensor excitation voltage, a digital RS485 and an accurate 0.1% analog interface.
      The environmental standard for a low cost digital interface is for 5V sensor excitation with digital interface using the SDI-12. I was wondering was there any click sensor boards that provide these.. I looked, but not for very long.I have been using the commercial Onset U30 loggers, 12V excitation with analog 0.1%, and even with these, one of the real world challenges is varied powering and easy of setting up in the field.
  • Guy McCarthy posted an update 2018-01-04 4:52
    I’m developing a couple of inexpensive data loggers (open source, of course) and looking for some input on sensors. What types are commonly used, and do they require 3V or 5V?The low-end board is powered by a single AA and uses local memory for storage, with BLE for control and data transfer. It can provide 3V to external sensors. The mid-range board operates at both 3V and 5V, and includes a LoRa radio for long range, wireless data transfer. Any suggestions from the list are most welcome! Cheers, Guy

    • Jeremy Hise posted a new activity comment 2018-01-04 14:01:06
      Hey Guy, I am relatively new to this but have solved a few problems. I can’t really answer your question because I feel like the science objectives would really need to drive the sensor selection. If you are looking to reach a broad audience, then I guess I would go with some generally applicable environmental sensors such as temp/soil moisture/etc. However, I can tell you that precision will be important. For this I use the ads1115 from adafruit. The second problem you will encounter is battery life. I’m not sure what you mean by BLE, but my first attempt at low-power remote sensing was with the Arduino pro mini 8hz 3.3V. Good luck! Jeremy
    • neilh posted a new activity comment 2018-01-04 17:27:30
      I echo Jeremy Hise . To play with wireless (BLE & LoRa) that can be close to or embedded in the top 6″ of soil then temperature, humidity and soil moisture. Of course so many “dust” sensors floundered in real world conditions that micros don’t like in the circuitry like humidity, and 2.4GH that is absorbed by real world vegetation.
  • Dave H posted an update 2017-11-13 4:26
    Hi everyone. I’ve been doing some work of a general purpose datalogger software framework that can be applied to the Mayfly. The code handles all the common tasks such as interfacing to the SD card, time-stamping and event timing. There is a corresponding laptop application (written in Python) that handles tasks such as file download and manual triggering of log events. The code, as it is, is located at https://github.com/Coweeta/datalogger_tools. By using this framework, a researcher should only need to write code specific to their application. For an example of this see https://github.com/Coweeta/datalogger_tools/blob/master/sketches/mayfly_example/mayfly_example.ino
    Cheers, Dave
  • Luis Andres Guillen posted an update 2017-06-07 17:51
    Hello, In order to charge the battery of the Mayfly with a solar panel, do I need to put instructions in the code?
    If so were do I find that line of code?
    In case the mayfly doesn’t need any code to read the solar panel, Why isn’t my mayfly getting charged from the solar panel?
    Thanks in advance, Luis Andres Guillen

    • Shannon Hicks posted a new activity comment 2017-06-07 18:16:21
      No, no additional code is needed for a solar panel to charge the Mayfly battery. What kind of panel are you using, and what type of battery? If you connect a 6v solar panel with a standard JST-style connector to the “SOLAR” port of the Mayfly, it will charge any single 3.7v LiPo battery connected to the “LIPO BATT” port.If you have really good eyesight, or have a magnifying glass handy, can you tell me what letters are printed on the tiny black 5-pin chip (labeled U1) that’s mounted on the Mayfly between the SOLAR and LIPO BATT. sockets
    • Luis Andres Guillen posted a new activity comment 2017-06-07 18:30:48
      Thanks for the prompt answer.
      The panel should be from the starters kit from last year, around the Cuashi meeting. I got it from Nicolas.
      I have the connected it that way. Panel to SOLAR and Battery to LIPO BATT JP2
      The letters are KE3J.
    • Shannon Hicks posted a new activity comment 2017-06-08 04:31:49
      If you have a battery connected to the LiPo jack, you should see a yellow LED light up next to the battery jack whenever the solar panel is connect and placed in the sun. You should also see the yellow LED if you have a battery connected and you plug a USB cable into the Mayfly, because the charging circuitry can be powered by either a solar panel or the USB cable. You’ll see this even if the Mayfly board power switched is turned off because the battery is charged anytime there’s solar or USB power applied to the board. If you have more than one Mayfly board, verify that the panel and battery work with other boards. If you’ve got more than one battery and/or panel, switch those around too. You should be able to narrow down whether it’s the board, panel, or battery that is consistently causing the error.
    • Luis Andres Guillen posted a new activity comment 2017-06-09 12:12:28
      Thank you! I had not noticed the yellow led, that is really helpful to know if it is charging. I went through the connections again and it seems to be charging now! Thanks again!
  • Luis Andres Guillen posted an update 2017-05-15 18:05
    Hello, Does anyone have experience in connecting a Campbell Scientific CS616 Water Content Reflectometer to the Mayfly?
    In that case how do I go about it? How much power would I need to sample every 30 minutes?
    I am new to this field, so all comments and direction are really welcome. Thanks, Luis Andres Guillen

    • Shannon Hicks posted a new activity comment 2017-05-17 13:42:54
      I haven’t used one of those before, but it outputs a square wave that’s frequency is proportional to the soil moisture, so your logger would have to do some frequency measurements and then convert that to VWC using a formula. But that particular sensor has a low (0.7v) output, so you’d probably want to use the CS625 sensor, which is the same as the 616 but has a 3.3v output, which is what the Mayfly would want to see. The sensor needs 5v excitation though, but the Mayfly can provide that if you switch over the jumper. Most of the frequency-counting libraries for Arduino use interrupts, so you’d probably want to use the D10 hardware interrupt pin for reading this sensor. It might also be easier to use a separate frequency-to-voltage chip to do the frequency measurement offboard and simply read the chip’s output voltage with a Mayfly analog pin. Note that the sensor has a maximum VWC of 50%, and I’ve seen levels higher than that in many of my deployments. Are you using this sensor somewhere where you don’t expect high moisture levels? There are other sensors from other manufacturers that cover a wider operating range and have a much more convenient digital output if you’re willing to consider other hardware options.
    • Luis Andres Guillen posted a new activity comment 2017-05-23 12:04:06
      Thank you very much for the information Shannon. I have already several of those sensors, so I wanted to put them into use. I’ll check which type of water content they have found in the site to see if that is an appropriate sensor. Thanks!
  • JimMoore posted an update 2017-01-31 1:44
    Thanks, I think I will go with the blob on the battery.
  • JimMoore posted an update 2017-01-30 03:34:59
    I tried out the “Sleeping Mayfly logger example” and after I had installed the needed libraries and the sketch compiled I got an “SD card missing” error. The problem was that SD_SS_PIN in the example was 11. Worked fine when I changed it to 12. Is this the case for all Mayfly boards or was there a revision somewhere?
    While playing with this code my RTC got reset and this has happened a number of times and I am fairly confident that the watch battery is snug. Any thoughts on why this is happening?

    • Shannon Hicks posted a new activity comment 2017-01-31 00:20:22
      The SD select pin on all versions of the Mayfly is pin 12. There was an error in that example, so I just fixed it. As for your RTC losing time, I think you have a board that was sold before I started modifying all of the boards with a small blob of solder on the board under the battery holder. If you have a fine tip solder iron, you can do this yourself, or you can just add the solder to the bottom (negative pole) of the battery as shown in this photo: http://envirodiy.org/topic/rtc-time-kept-without-power-has-cr1220/#post-1606
  • Jeremy Hise posted an update 2017-01-05 14:10
    Hi all, I’m pretty new to data logger development but have certainly gotten my feet wet. A project I am currently involved in requires measuring tiny changes in tree stem growth. So tiny, in fact, I believe I have to deal with signal noise from my power source/14 bit ADC. I know I can apply some statistical methods (ie. averaging with oversampling) to deal with noise but is there any circuitry that can be used as well, such as a low-pass filter? I would love to hear about general approaches to this problem. Thanks!

    • neilh posted a new activity comment 2017-01-06 16:52:02
      Hey thanks for posting. Interesting issue.
      Noise in circuits is well studied and a deeeeeep issue. In circuits there are two types of noise to manage, faster than 1hz and then probably your main concern and more challenging less that 1Hz . Filtering out noise is useful at higher frequencies where low frequency noise is not an issue.
      Managing noise in measurements is considered a magic art – the first step is to reduce it with selection of low noise components, and then good circuit design. To do that you need to look for the noise specification of components – and its good to understand the different types of noise. You are probably interested in shot noise, thermal noise,
      However component drift may also be an issue with measurement – which is not strictly noise, but is variations in a sampled signal.
      The blogs I’ve been posting on measuring low water levels are all essentially about characterizing the low frequency noise sources in the sensors+amplifiers+digitization circuitry. The manufacturer’s have put out product specifications, and the characterization is partly about determining the way they are trading off different solutions to the front end sensors they have chosen.I’d be interested in the equipment you are thinking of using.See this link here to my blog….. http://envirodiy.org/comparison-temperature-dependency-in-situ-lt500-and-keller-nano-level/ 
    • Jeremy Hise posted a new activity comment 2017-01-07 02:05:57
      Wow some great info. Thank you very much and I will check out the your blog as it seems this career path will be heavily involved in these kinds of problems. The design is straight forward, a Li-Polymer battery, arduino pro mini with the ADS1115, xbee series 2 and a Midori Precisions linear sensor…essential a variable resistor up to 1K. Trees are constantly soaking up water but the transpiration during the day causes their main stem to shrink. This stem size change is what I’m trying to measure which, depending on the species, can be up to about 6 microns. I’ve done some rough measurements but need to get it under the oscilloscope to measure the Hz. The noise is obfuscating the tree stem size change but I’m hoping there will be a way to differentiate between the slow change in voltage produced by stem size changes and the much higher frequency noise.
      One requirement of the project is battery longevity, hence the pro mini. https://ssl.alpha-prm.jp/midori.co.jp/english/index.php/products/detail/20 Thanks! jeremy
    • neilh posted a new activity comment 2017-01-07 05:52:05
      Hey Jeremy,
      Interesting project there – I’ve wondered about the effect on the trees when they are really transpiring in a heat wave,
      and also what the delay was between heat peak for transpiration, and pulling the water from the ground, and stream.
      So looking to measure 6microns, or 0.006mm across the LP-10F travel of 10.0 mm
      I’m guess maybe you are looking for some resolution within this possibly 0.006/16 mm? n
    • Jeremy Hise posted a new activity comment 2017-01-07 14:48:06
      Those are some great questions. Tree water/soil/atmospheric relations is where a lot of this work is pointed. Some species, like the Picea abies, can swell up to 0.006 mm in a 24 hour period, others less so, so I’m looking to detect changes within the 0.000-0.006mm range.Generally speaking, would one start with identifying noise at the power source and tracing additional noise along the “chain” of components/sensors? Is it possible that a linear sensor would introduce new signals? jeremy
    • neilh posted a new activity comment 2017-01-07 19:04:58
      I think you have to look at all the noise sources with the level of measreument that you are looking at. So broadly for a 0.006mm range, you want some resolution in it, which defines what exactly is your 0. That in turn will translate to the noise floor that you need to exceed. So so you could use a scale of 16 – then you need to be able to measure 0.006mm/16 which is 0.000375 mm – which is very small.
      Possibly a challenge for the LP-10F which isn’t specifying anything to suggest it can be used for such “micromovements”. Its suggesting an Output Smoothness of 0.1% – which for 10mm would suggest 0.01mm – so I wonder what Output Smoothness is. Also the TCR (temperature coefficient of resistance) of the LP-10F seems very high. What daily fluctuation of temperature do you think the measurement apparatus will be subject to.?
      So just checking and wondering where the suggestion for LP-10F came from – wondering if it has been used before for such an operation – just wondering if there is something that is known about it not stated on the data sheet.
    • Jeremy Hise posted a new activity comment 2017-01-09 15:13:13
      Neil this has been such a great conversation. Thank you.I don’t understand the scale of 16. Could you elaborate or point me to a reference. I’m having a hard time googling that one. This sensor is a “cheaper” version of one that is in the field being used exactly for this purpose. That sensor has a temp. coefficient of +-400 ppm/K. This seems to be specifically relevant to the resistance applied to the voltage of the device. This will be deployed in the field during spring/summer/fall so a temp range of 15F wouldn’t be surprising. The sensor was more or less supplied/suggested by the project manager who works on the science side. Again, the LP-10F is cheaper than the LP-20F and was assumed they where more or less the same, though the temp coefficient is obviously better on the 20F. Also to note is there is a known voltage sensitivity of 1mv=4.0micrometers. Would this mean that for each mv the variation would be mv*4.0 basically? https://ssl.alpha-prm.jp/midori.co.jp/english/products/pdf/LP-20FB.pdf Jeremy
  • neilh posted a new activity comment 2017-01-09 18:50:44
    Hi Jeremy
    My reference to 16 was that for a total change of 0.006mm its going to be broken down to a scale, and if you choose 1/16 (as its digital) then for 0.006mm/16 you would have a target of 0.000375 mm – which is very small.
    Now looking at the LP-10F spec – which with a total travel of 10mm is better than 20mm for measuring something very small.
    However looking again at LP-10F spec – not knowing anything about the device – is it mechanically capable of accurately detecting 0.000375mm change of distance.
    So I’m just asking the question – since I don’t know anything about the LP-10F devices – is it capable mechanically of measuring a change of 0.000375mm – when considering wiper action, the everyday cycle of changing direction while the tree trunk expands/contracts – also known as hystersis.
    So just an initial “dumb question”, before looking at the electronic noise and effects of temperature change of 15C.
    Of course it is possible to measure very small changes of distance, across very large distances – and the latest most well known (with a hefty price tag..
    is the LIGO – they talk about measuring a change of 10E-18m across 4000m.!!!

Researchers Group

  • Ronald Tirino posted an update 2018-04-06 18:57:37
    microbial biodiversity in urban wetlands
  • kevin ryan posted an update 2018-02-03 16:44:00
    I am searching for recommendations and resources to construct a low-cost ultrasonic water level sensor for use with trapezoidal flumes on small streams

    • fisherba replied 2018-02-08 17:02:00
      Hi Kevin, we are using and like the sensors from Maxbotix. Here’s an old blog post by @shicks to see one compact enclosure option: https://envirodiy.org/ultrasonic-water-depth-sensor/. (the forum limits how many links I can give you, so this will come in several posts)
    • fisherba replied 2018-02-08 17:02:00
      https://www.maxbotix.com/Ultrasonic_Sensors/MB7389.htm has a range of 30-500 cm.
      https://www.maxbotix.com/Ultrasonic_Sensors/MB7386.htm has a range of 50-1000 cm.
      https://www.maxbotix.com/Ultrasonic_Sensors/MB7955.htm makes temperature compensation integrated with the MaxSonar (and there’s a solder it yourself kit for 1/3 cost).
    • fisherba replied 2018-02-08 17:02:00
      Scripts are available in the modular sensor repo: https://github.com/EnviroDIY/ModularSensorsAlso notable, we like to drill and tap plastic enclosures and screw the MaxSonar straight into the enclosure.
      https://github.com/EnviroDIY/EnviroDIY_Mayfly_Logger/blob/master/hardware/1120Pelican_enviroDIY_5.pdfLet me know if you have other questions. Sorry it took a few days for you to get a response!
    • Kevin Stokes replied 2018-03-26 16:19:00
      I have a couple of high school students making a water-depth sensor with the MB7389 ultrasonic sensor and a Mayfly data logger. The information you posted has been very helpful. We are also using the Pelican 1120 case. The problem we are having is attaching the case/MB7389 to the top of the 4″ PVC pipe that we are using for a stilling well. Any suggestions?
    • fisherba replied 2018-03-27 03:13:00
      Hi Kevin, I’m not sure about an elegant way to mount a pelican case to the pipe. My current cases are all pole mounted with two 10″ zinc mending plates mounted to the back of the Pelican case using bonded sealing washers to keep the case dry. Then the mending plates are mounted to a post in the ground. If you have only ultrasonic sensors on the well, I think what @shicks did here is very elegant and way less expensive than Pelican cases: https://envirodiy.org/ultrasonic-water-depth-sensor/
    • Kevin Stokes replied 2018-03-27 16:34:00
      Thank you. I checked out the link, that is very nice. Right now we only have the ultrasonic sensor, but I wanted to add temperature sensors for water and air. In the future, we might add a rain gauge.
    • fisherba replied 2018-03-29 14:56:00
      Kevin, I was just thinking, how about mounting a PVC end cap to the back of the pelican case (so the door of the case is on top) and drill and tap the PVC and case to accommodate the ultrasonic sensor? It would look something like the one linked above, but roomier. Then you have the case mounted as a sort of well cap and you have room to add additional sensors as needed to the system over time (by tapping with cord grips as needed). It seems like it would be pretty trivial to create a clamping system on the outside of the the well to hold the pelican case/cap on the top of the well in a stable way. The 1120 case is pretty small. (P.S. we should really be having this discussion in a forum so it’s searchable in the future by others!)
  • Kelly Stettner posted an update 2017-11-22 17:40:59
    Hoping to learn if any of you are working with the organisms in the hyporheic zone of streams/rivers?
  • Kelly Stettner posted an update 2016-03-22 18:58:58
    I’m working on sampling the meiofauna in the hyporheic zone near a contaminated river bank in southeastern Vermont. These are the microscopic critters that live in the water that is in-between grains of substrate under the bed of the river…where groundwater wells up into the river. Tried using colonization tubes last year, with no luck. Going to attempt a push-point sampler with a 600 micron screen to see if we can suction out any creatures (hopefully we can get critters in the 50-microns-or-less range) to catalog under my microscope.

    • Kelly Stettner replied 2017-11-22 17:39:00
      Still working on this…I now have a compound ‘scope to look for creatures, but all I’m finding so far is tiny rock crystals. Am I not digging deeply enough? The push-point can only penetrate an inch or so down…not the 6″ that I’ve seen mentioned. The river bottom is VERY rocky, I don’t really see a way to get deeper than an inch or two.
  • Anthony Aufdenkampe posted an update 2016-02-18 19:57:44
    All members of this group can post to this group. Tell us what kind of research you are doing and why you joined EnviroDIY?

Sensor Developers Group

  • Masahiro Hayashi posted an update 2019-12-23 10:19:19
    Hi All, I am developing with Yosemitech water quality probes.
    However, I have been having trouble contacting Yosemitech since last week (December 16, 2019).
    I’m worried that Yosemitech may have shut down. Has anyone contacted Yosemitech last week?The product page(DO Probe) of Yosemitech is not displayed. http://www.yosemitech.com/en/product-cat-4.html I would be glad if I could get the information.

    • TroyB replied 2020-01-22 03:59:56
      I have looked several times since you posted this, and was pleased to see that the Yosemitech pages appear to be live again now.
  • Oscamo posted an update in the group
    Following up on @roryg‘s earlier post – what are the actual ranges of turbidity that you guys see in the field? The Campbell probes claim to measure 0.5-4000 NTU, do you see the full dynamic range in the field? How accurate is “good enough” ? Thanks!
  • Rory G posted an update 2019-12-13 19:35:00
    Hi All, FYI, the Turbidity sensor linked to is set to be discontinued as of Dec 29th, 2019. Does anyone know if EnviroDIY is planning to specify another turbidity sensors for their set up?

    • Shannon Hicks posted a new activity comment 2019-12-13 20:25:00
      The manufacturer of the turbidity sensors we usually use (Campbell Scientific) will be releasing a new version of their sensors soon, so we are working with them to make the appropriate changes needed to accommodate the new sensors. We’ll release more information when they announce that their new sensors are available.
    • Rory G posted a new activity comment 2019-12-13 22:35:00
      Fantastic. Thanks for the response and I’m looking forward to information on their updated sensor. Let’s hope the price comes down a little bit. 🙂
  • Diatrix posted an update 2019-08-01 19:40:25
    Hello everyone. I’m slowly developing a water quality sensor to monitor water pollution in underground krastic river systems. The main pollutant in these waters is fecal matter from lack of proper water treatment, and sewer systems. This pollution drains on the ocean, where it damages local reefs and it also pollutes local cenotes. Both of these have a great impact to the local economy, which is based on tourism.Anyways, I’m currently stuck on a way to monitor in real time the amount of fecal matter in the water. I’ve talked to a local hydro-biologist, and he tells me that the way to monitor fecal matter in water is by taking samples and measuring the fecal coliform bacteria in the water. I don’t see a way to do this with a real time sensor. I’m wondering if someone here knows of a sensor to monitor the fecal matter in real time.The environment i work in is underground, slow-flowing rivers with two distinct layers of water: a salt water layer, and a fresh water layer. Some times they mix, and the level of the edge is not constant, and changes depending on the weather and tides.I thank you all in advance for your help. -Diego

    • Luis Andres Guillen posted a new activity comment 2019-08-01 20:27:00
      Hello Diego, That is an interesting project. Is it in Yucatan Peninsula?
      I think that the advice that you have been given is correct. I don’t know of any sensor that can measure fecal matters real time. The usual way is to monitor the water at fixed intervals, and take the samples to the lab where they can tell you if the bacteria is present.
      What if you can measure another variable that can serve as proxy for the water quality? e.g. Turbidity or Dissolved Oxygen
      Or maybe some new technology can be tested in your system, see e.g.
      https://www.sciencedirect.com/science/article/pii/S0043135418301817 Saludos, Luis Andres
    • Diatrix posted a new activity comment 2019-08-01 21:24:00
      That’s what I was thinking. I’ve been researching fluorescence spectroscopy to make a meter, but I feel like the optical filters would not be cost effective. Although I’ve seen some other comercial products that use them. (See: https://youtu.be/0uipKkfs1rs). The idea is to have a large array of sensors, to find the sources of the pollution.Yes, it’s the Yucatan Peninsula. I’m based in Tulum. Here is what the problem looked like 8 years ago, I can only imagine what it looks like now.

      Perhaps I can do the Dissolved Oxygen, Turbidity, Salinity and temperature. How do you measure the DO?
      Thank you for your reply. Diego
    • Patrick Lorch posted a new activity comment 2019-08-01 20:27:00
      No such sensor yet exists. The best you can do is correlate turbidity from a sensor with measurements from water samples.
    • Diatrix posted a new activity comment 2019-08-01 21:25:00
      Thank you for your reply!
  • Mark posted an update 2019-07-30 20:46:00
    Does anyone have any experience with these 24v 4-20ma depth sensors from China?
    I have a few and they seem well constructed. We are working on integrating them with the Mayfly.
    This requires A) a 24 volt voltage source. (We are trying https://www.amazon.com/QEBIDUL-Converter-Step-down-Regulator-Stabilizer/dp/B07BTHSK8H/ref=sr_1_5?keywords=5-30+volt+dc+to+dc+converter&qid=1564408261&s=industrial&sr=1-5) and B) some input components to measure the current and protect against over voltages. Any recommendations would be appreciated.

    • neilh posted a new activity comment 2019-07-31 03:52:00
      Hi Mark Thanks for sharing – just wondering what your power supply source is. Are you solar powered, running of the LiIon battery or another source.
      Technically the spec says “Power Supply:12~36VDC” – that is nominally 24V, but actually a range. That would fit with the https://github.com/EnviroDIY/SensorModbusMaster/tree/master/hardware/Modbus-Mayfly_WingShield
      If you really need the 24V then there is a step up regulator U3V50F24The RS485 SOM specified in the Modbus-Mayfly_WingShield does have some protection on it – but the PCB traces are weak for the protect diodes return path to a ground. It would be simple to add a straight wire to beef up that and use the RS485 SOM .Have you found the manual specifying the Qidian QD-130 sensors registers to see if they are compatible one of the Maylfy RS485 sensors.
    • Mark posted a new activity comment 2019-07-31 18:06:00
      Thanks for the great information. I will look into these items and get back.
    • Mark posted a new activity comment 2019-08-01 17:37:00
      We are planning to be solar powered using a 2500 mAh 3.7V battery and Voltaic Systems 2W/6V solar panel
    • neilh posted a new activity comment 2019-08-01 19:24:00
      It sounds like the RS485 Wing Shield would work for you, probably standard voltage option but you should check it works. It does require assembly and soldering.
      I was wondering if you have the sensor manual including data protocol and what RS485 registers,
    • Mark posted a new activity comment 2019-08-01 19:30:00
      No manual. Just a data sheet I can’t read
    • neilh posted a new activity comment 2019-08-01 22:32:00
      Hello Mark – oops I’m thinking in another dual world – my brain fart.
      The sensor is 4-20mA (i’m using that type of sensor in non-mayfly Onset U30 loggers and trying to move to Mayfly/RS485).
      The 4-20mA with excitation 12-36V is much simpler, but it is not supported directly by Mayfly.
      The excitation voltage can be done with the switched voltage booster portion of the RS485 board, and a current measurement device calibrated for the 20mA. Let me think about it and post back here
      How many are you looking for?,
      How willing/experienced are you to a) solder build boards and
      b) compile a software Mayfly build
      c) how are you looking to log the readings 1) SD card 2) WiFi to [data.envirodiy.org or..] 3) Celllar or …”
    • Mark posted a new activity comment We are expecting to do a little soldering and working on the Mayfly sketch. The data will be sent via Wifi to our own server and to EnvironDIY
  • neilh posted a new activity comment 2019-08-02 00:04:00
    So to restart the thread – it can be done with RS485 wing board to generate a switched excitation voltage (from the LiIon). The voltage probably needs to be 14V+ so could be U3V50F24 to generate 24V.
    To measure the 4-20mA accurately use Adafruit INA219 with a 10ohm resistor.
    The Mayfly has the INA219 drivers, I submitted them, but they are a version of the Adafruit drivers.
    It probably makes sense to create a version of the INA219 driver as a 4-20mA sensor with switched excitation. The resistor could be an option to the driver, and for 10ohms a 20mA FullScaleReading, would be 0.2V. The INA219 measures voltage to 0.32Vs, and this would be calibrated to produce a mA measurement.
    I would recommend a 10ohm YR1B10RCC -$0.62 (accurate 0.1% with a low temperature drift 50ppm/C) https://www.digikey.com/product-detail/en/te-connectivity-passive-product/YR1B10RCC/A105944CT-ND/3477513

  • Mark posted an update 2019-06-13 17:40:00
    Hi I am planning to set up some monitoring stations to monitor the Conductivity, temperature and water level in different areas around our county. Does anyone have a recommendation for a lower cost conductivity and temperature sensor?
  • Rick Vogel posted an update 2016-03-11 14:02:00
    I had a recent question from a person stationed in Alaska regarding ice thickness measurement. They already perform the drill and measure method, but was wondering is there was any hand held instruments or other smaller device that can measure without the need for drilling through the ice. Please let me know if anyone has heard of such a thing. Thanks!!
  • Rick Vogel posted an update 2015-09-22 17:25:00
    Anybody aware of a source for probe style enclosure that could have filter cap screwed on top. I would like to put my sensor board in a probe housing but can’t seem to find that type of enclosure around anywhere.

Teachers Group

  • Shannon Hicks started the topic Teacher workshop – July 17 in the forum Teachers 2018-07-13 20:00:00
    All-Pro Teachers Workshop
    Date: Tuesday, July 17th
    Location: Stroud Water Research Center: 970 Spencer Road, Avondale PA 19311Workshop begins at 8:30 a.m.Science and technology teachers are invited to join the All Pro Teachers Workshop at Stroud Water Research Center. A few spots have recently become open for this special workshop that is fully sponsored by Axalta Coating Systems in partnership with the Philadelphia Eagles. The workshop includes a day of learning about LEED Platinum sustainable building and grounds features, stream physical habitat assessment, water chemistry, and aquatic macroinvertebrate collection and identification while using an iPad app called Water Quality to log and make sense of the data.A Philadelphia Eagles player will join the day’s activities! Teachers will receive instructional materials and Act 48 credits. To register for the event simply email Jess Provinski, jprovinski@stroudcenter.org
  • Trish Bacon posted an update 2017-10-12 16:07:00
    The Pilot School has successfully launched a sensor station! The acquisition of the water monitoring system was facilitated by a grant from the Stroud Water Research Center in conjunction with the EPA. On September 6, right before a rain, the data logger began recording the amount of water in the retention pond just beyond our parking lot. After analyzing data, students quickly realized that the water from the rain is being absorbed into the ground rather than flowing directly into the creek. This led students to begin asking questions about the importance of this pond and the effect on the environment.

    • David Kline replied 2017-10-14 21:59:00
      That is AWESOME Trish! David and Shannon are headed to our school on Monday to install our sensor! We are so psyched!- @ Montgomery School, Chester Springs, PA
  • Andre DeLorme replied to the topic How easy to set up? 2017-10-11 16:46:00
    Shannon – thanks for the reply. I first heard of the EnviroDIY at the Society for Freshwater Science annual meeting this summer. They mentioned that there may be workshops to “train the trainer”, is this a possibility? Any chance you could come back out this way to do a little training? We are not as large as the Western Minnesota River Watch program but would like to get our schools involved in this program.

    • Shannon Hicks replied to the topic How easy to set up? 2017-09-27 13:46:00
      We designed the Mayfly logger system to be very easy to build and deploy. In fact, we’ve been teaching workshops to school groups and citizen scientist programs for the past year and I was actually in Grand Forks, ND earlier this summer where we gave a 2-day workshop at UM-Crookston. With most of our school workshops, we taught middle-school and high-school students some basics of electronics and coding/programming, and then we gave them kits and let them build a logger, assemble everything in the waterproof enclosure, and then show them the tips and techniques needed to successfully deploy the station in a stream. We also talk about maintenance and troubleshooting and how to QA/QC the collected data, and and some general scientific background to help them understand why we’re collecting the data and what the different parameters (turbidity, conductivity, pH) mean in the big picture. This was all part of a pilot program from the EPA to develop workshop materials and teaching curriculum based on the Mayfly board and various sensors. If you’d like, we could send you some of the information when it’s published.And as for the circuit boards themselves, they are very simple to use. We can supply the code you need to program the board for most logging deployments (most of it is already available on our Github page), and almost all sensors simply connect to the board with simple jacks or screw terminals, so there’s no soldering or electrical engineering background needed. It gets powered by a small LiPo battery with a small solar panel to keep it continuously charged. The hardest part is making sure the enclosure you mount the sensors in is waterproof, and that you install the sensors in the water in a way that gives reliable data and can withstand floods/ice/mud etc. We use a variety of sensors from low-cost short-term deployable sensors to rugged research-grade sensors that require much less maintenance but cost several times more. So choosing the sensors really depends on your budget, how often you want to maintain them, and the quality of data you want to record. Using the Mayfly is not much harder than any other modular logger/sensor station you could build from other, more expensive commercial hardware options. In the end, you’ve still got to protect a logging device from the weather by putting it in some sort of enclosure along with a source of power, then mount your sensors and hope they can survive whatever flood events will eventually happen. The Mayfly significantly lowers the entry cost for building a station, plus you can use just about any sensor you want from any manufacturer without worrying that it isn’t compatible with a different brand. Plus you can use the Mayfly for any other regular Arduino-type microcontroller project, so it is a very versatile little circuit board.
    • Andre DeLorme started the topic How easy to set up? in the forum Teachers 2017-09-25 17:48:00
      I help run a River Watch program in North Dakota and we are interested in helping schools set up monitoring stations using the Mayfly system. How easy is it to do? It seems that there is a lot of program coding and working with circuit boards. Is this a barrier or is the process straight forward? I also have not been able to find much information on the types of probes to use. Specifically the brands and vendors of the probes in addition to how to connect them to the mayfly. We are interested in pH, specific conductivity, temperature, and dissolved oxygen. Any guidance is appreciated!
  • Trish Bacon posted an update 2017-08-11 21:33:00
    Thanks, Stroud, for a wonderful three-day workshop!
  • Kate R. started the topic Avon Grove Charter School in the forum Teachers 2017-08-11 18:50:00
    Here is the possible future site for our Mayfly Data Logger and Monitoring Station. We look forward to collecting data to compare with data collected from our leaf packs in order to determine the effects of temperature, conductivity and depth on macroinvertebrate life.
  • dsylvan started the topic Green Woods Charter School in the forum Teachers 2017-08-11 16:40:00
    Here is the pond at Green Woods. Deployment will be next to the dock and pump.
  • dsylvan posted an update 2 years agoHi
  • Heather Brooks posted an update 2017-08-03 17:23:00
    Something I forgot to mention: the activity within an EnviroDIY group is separate from the “blog” area of website. Blog posts are like news articles that get featured on the homepage. They need to be approved by a site admin before they are published. To share with just your own group, make sure you start on your group homepage and write either a status update or forum topic. If and when you’re ready to write an article for the entire community, that’s when you choose Blog > Add Blog Post in the main menu.
  • Heather Brooks posted an update 2017-08-03 17:05:00
    Hi everyone, and welcome to the EnviroDIY teachers group! As you familiarize yourself with the group features, please feel free to ask me any website-related questions, either publicly by mentioning me (@heather) in a status update in the group, or privately by emailing webmaster@stroudcenter.org.
  • Michael Podlesney started the topic Downingtown STEM Academy Mayfly Site in the forum Teachers 2017-08-03 16:52:00
    Here is our site along Beaver Creek near Tabas Memorial Park.