We are really interested in measuring various water quality parameters that are relevant to environmental health in low-cost and accessible ways. A lot of people have been working on developing low-cost, open-source sensors for water chemistry and physical properties (see https://publiclab.org/wiki/open-water), and there are also several commercially available water sensors and analog tools that can measure relevant water quality parameters. 

Embedded here is a spreadsheet with a few example of different kinds of tools for the parameters listed below. Are there other parameters you are interested in measuring? If so, please add them to the list here and to the linked Google Doc! Parameters people have expressed interested in include:  

- ammonia/ammonium 

- colorimetry 

- conductivity/salinity 

- depth/pressure 

- dissolved oxygen 

- flow rate 

- nitrate 

- oxidation-reduction potential 

- pH 

- temperature 

- turbidity/TSS 


Even though this wiki page is labeled "water sensors," the most accessible modes of measuring water quality parameters are often analog, non-digital methods where you directly observe water (e.g. using a secchi disk to assess turbidity) or collect a sample and test it with a visual method (e.g. color-change pH strips). Several analog tools are included in the spreadsheet, and please add more! 

Most of the sensors listed in the spreadsheet are probes that require you to physically be present at the body of water such that you can hold the probe in the water. A few others are sensors that can be deployed for longer periods of time without supervision, either with a remote data upload or an in-sensor data logger that can be retrieved every couple of weeks. The type of sensor -- a probe, a deployable sensor, or a tool requiring sample collection -- is listed in column C. 

https://docs.google.com/spreadsheets/d/1UwjRqU8kHTwEcnDdO2Zxkr8zkFkaGfyePJ-cdnxJzw0/edit?usp=sharing