Smart Turbidimeters for Remote Monitoring of Water Quality

EPA Grant Number: SU835732
Title: Smart Turbidimeters for Remote Monitoring of Water Quality
Investigators: Ball, William P.
Institution: The Johns Hopkins University
EPA Project Officer: Page, Angela
Phase: II
Project Period: October 1, 2014 through August 31, 2017
Project Amount: $89,995
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2014) Recipients Lists
Research Category: P3 Challenge Area - Built Environment , P3 Challenge Area - Water , Sustainability


Turbidity – the “cloudiness” of water caused by light reflecting off of suspended particles – is recognized globally as an important water quality parameter. Even though turbidity is not a physical property of the water (like pH or hardness), water treatment technicians routinely use turbidity readings to determine necessary dosages of coagualants and disinfectants, and to assess potential issues in water distribution pipe networks. Turbidity is not easily assessed visually, and current commercially available machines for assessing turbidity – known as turbidimeters – cost hundreds to thousands of dollars. Moreover, turbidimeters are not typically designed to be user-reparable and do not typically contain internal telecommunications capabilities, complicating the application of this technology to rural and developing-country contexts where affordable remote water monitoring is needed.


Our team will design, construct, and test handheld and inline versions of low-cost turbidimeters that are suitable for basic water quality monitoring. These devices will contain open-source hardware and firmware, will be user-reparable, and will be an order of magnitude cheaper than currently available commercial alternatives. In Phase I of our P3 grant, the team successfully demonstrated a reliable handheld turbidimeter (that can be constructed for roughly $25) that can be paired to an Android phone via an internal Bluetooth unit. This battery-powered turbidimeter successfully communicated data to a web server via coded SMS messages (a protocol we have designed, known as OpenSourceWater). For Phase II of our P3 grant, the team will design and fabricate printed circuit boards for the turbidimeter, improve two-way communication between server and turbidimeter, and produce prototype turbidimeters with internal GSM modems (allowing two-way communication over cellular and wifi networks). While we will not use EPA funding for product commercialization, we will design the entire production chain to be commercially scalable, to help ensure the post-grant sustainability of this project.

Expected Results:

Before the expiration of funding, we expect to have identified and tested affordable designs for handheld and inline turbidimeters well-suited to developing-regions contexts; capable of providing reliable data and relaying these wirelessly. All research products from this project ill be open-source licensed, and made freely available to the public. We have published a description of our handheld turbidimeter and expect additional publications.

Supplemental Keywords:

Arduino, nephelometry, NTU

Relevant Websites:

Phase 1 Abstract
Phase 1 Final Report

Progress and Final Reports:

  • 2015
  • 2016
  • Final

  • P3 Phase I:

    "Smart" Turbidimeters for Remote Monitoring of Water Quality  | Final Report