Assess Turbidity in Water
turbidity

As explained [in @donblair's primer](/notes/donblair/08-25-2015/turbidity-001), measuring turbidity means "measuring the amount of suspended solids in water -- solids that haven't fully dissolved". That is, "turbidity, an optical technique for assessing suspended solids in liquid -- is an important water quality parameter. Typically, light is shone into a liquid sample, and the amount of light scattered back out of the sample (off of particles suspended in it) is measured; the intensity of this scattered light is considered to be related to the amount of suspended solids in the sample." ([reference](/wiki/turbidity_sensing)) _image credit: https://castlebrookestreamstudy.weebly.com/_ This page needs help! * Info about regulations * Info about ecological or human health impacts * Advocacy leverage points * Constraints we're working within: cost, complexity, sensitivity, time There are a LOT of resources available on these pages by @donblair and others: * https://publiclab.org/notes/donblair/08-25-2015/turbidity-001 * https://publiclab.org/wiki/turbidity_sensing **** ## Questions [questions:turbidity] **** ## Sensors Here's a list of different turbidity sensors and measurement systems. See below for some Do-It-Yourself approaches to measuring turbidity, and [this page](https://publiclab.org/wiki/turbidity_sensing) for more information on how turbidity sensors works. * Kelley et al., An Affordable Open Source Turbidimeter http://www.mdpi.com/1424-8220/14/4/7142/pdf * Hackteria.org, Turbiduino: http://hackteria.org/wiki/DIY_turbidity_meters * Lambrou et al., A Nephelometric Turbidity System for Monitoring Residential Drinking Water Quality: http://www2.ucy.ac.cy/~faniseng/publications/SENSAPPEAL09.pdf - Fondriest review: http://www.fondriest.com/environmental-measurements/equipment/measuring-water-quality/turbidity-sensors-meters-and-methods/ - Hach overview: http://www.hach.com/asset-get.download-en.jsa?code=61798 (see [Water sensors](https://publiclab.org/wiki/water-sensors) for more, and [click here to add to this table](https://docs.google.com/spreadsheets/d/1UwjRqU8kHTwEcnDdO2Zxkr8zkFkaGfyePJ-cdnxJzw0/edit#gid=28737041)) **** ## Activities Activities for people to test methods (these develop over time) [activities:turbidity] **** ## Existing work [notes:turbidity] ...


Author Comment Last activity Moderation
gretchengehrke "Hi @Mempet, Could you use a turbidity tube like this one: https://www.carolina.com/environmental-science-water-quality/carolina-turbidity-tube-120-..." | Read more » almost 5 years ago
gretchengehrke "@donblair, I was just reading this again, and am again impressed by your elegantly simple approach -- such a great idea! It seems like this alterna..." | Read more » almost 5 years ago
gretchengehrke "@bhikman, that integrated optical filter is neat, and surprisingly inexpensive! If you do pick this back up, I am super interested in seeing how we..." | Read more » almost 5 years ago
bhickman "Hi @gretchengehrke. I kinda let this project fall though the cracks. I did have the sensor working pretty well, the only issue was interference fro..." | Read more » almost 5 years ago
gretchengehrke "Hi @bhickman and @ggallant! I was just reading this research note and comments again, and it sounds like such a promising project. Are there any up..." | Read more » almost 5 years ago
gretchengehrke "That's so great, Shan! " | Read more » almost 5 years ago
shanlter ""Did the Chinese government state the methods they would use to evaluate each of these parameters?" yes, they state the standard methods. "Also, di..." | Read more » almost 5 years ago
shanlter "Hi @gretchengehrke, sorry for responding late, I was in a temple with no internet access in the passing week. Yes, I've seen that page and I though..." | Read more » almost 5 years ago
gretchengehrke "@shanlter, this is great! Have you seen the spreadsheet on the www.publiclab.org/wiki/water-sensors page? There are some other options there listed..." | Read more » almost 5 years ago
warren "Hi, Gretchen - do you have some examples of when and where this technique has been successfully used by folks? Thanks! " | Read more » about 5 years ago
jesseslone "@donblair I noticed you have a more recent post about turbidity, I was wondering if you would choose a different light sensor than the Adafruit one..." | Read more » over 5 years ago
eustatic "NOAA and Coast Guard made this guide "Job Aid" to observing oil slicks from the air. It's state of the art for government. OWJA 2012 Here's some ..." | Read more » almost 6 years ago
gretchengehrke "@tonyc, @mathew, @warren, @stevie, @donblair: I think an additional stretch goal that would be worthwhile is to be able to control the trap cam wit..." | Read more » almost 6 years ago
bhickman "Hi ggallant. Your design files look great! I'm going to have to look into openscad. As far as a server, I don't think publiclab has one. I think mo..." | Read more » about 6 years ago
ggallant "I parked the openscad design files at https://www.dropbox.com/sh/mzp8gketcuqufkq/AADkG_kmo2xcL3iWYOLi4YCxa?dl=0 If there is a better place, such a..." | Read more » about 6 years ago
bhickman "Hi ggallant. I'm definitely interested in what you have put together. I'll check out openscad to see what you have. As for the pipe and air bubble..." | Read more » about 6 years ago
ggallant "I have decided to suspend my current turbidity sensor and instead adapt yours to my base station. If it is of interest I have modeled the mechanica..." | Read more » about 6 years ago
bhickman "Hi ggallant. Sounds interesting. I'm trying to picture your design, but I'm not sure if I have it right. Can you post a picture? I definitely thin..." | Read more » about 6 years ago
ggallant "My current led and sensor boards are 6 sided and designed to attach to hardware store 3/4 plugs with plenty of epoxy and silicone sealant. Next rev..." | Read more » about 6 years ago
bhickman "Hi ggallant. I'm using Texas Instrument's Tiva microcontroller which has a couple pins that allow you to tap into the bus power (5V at 1A). For sho..." | Read more » about 6 years ago
ggallant "The LED is specified at 100ma. This "should" need a driver transistor. Outputs pins from the CPU are typically rated at 25ma max. " | Read more » about 6 years ago
bhickman "Hi gretchengehrke, thanks. To answer you questions: (1) I'm using this LED and this photodarling as the detector. The LED has a maximum output at 8..." | Read more » about 6 years ago
gretchengehrke "Hi @bhickman, this is great. Other folks (mostly @donblair) have been working on developing a turbidity sensor too. I have a couple of questions wi..." | Read more » about 6 years ago
bhickman "Hi ggallant. To answer your questions: 1. Yes, the unit is intended for submerged operation. So far I have only had it submerged in beakers in the ..." | Read more » about 6 years ago