Combining the latest nanotechnology with hydraulics may yield a promising solution to the costly problem of leaking water pipes in community public water systems, according to Yu-Feng Lin, a hydrologist at the Illinois State Water Survey, University of Illinois.

Lin and Chang Liu at Northwestern University developed a prototype of a wireless nanosensor that, when imbedded in the type of pipes that are typically used in public water supply systems, can monitor the temperature, flow rate, and pressure of water in the pipe.

According to the American Society of Civil Engineers, nearly 7 billion gallons of clean, treated drinking water disappears every day in the U.S. because of leaky pipes and mains at a cost of $20 to $100 million daily.

The current commercial devices for flow measurements are large enough to disturb the water flow field, providing less accurate data. The prototype 'Smart Pipe' is the first of its kind—and size—for this application.  Individual Smart Pipe sensors are too small to be seen clearly without a microscope.

The Smart Pipe device, which is half the size of a dime, contains multiple sensors connected to a wireless processor and antenna for transferring data to a command center in real time.  Like hairs on human skin, the sensor contains artificial hair that detects water flow from two directions, capable of detecting stagnant points, slow-flow sections of pipe, back flow, and leaks.

'Water flow bends the hair, which senses how much force is being applied,' Lin said.

The researchers also developed software to simulate a pipe network with various conditions.  The program can be used to predict, analyze, and verify measurements from a real-life system.

If the Smart Pipe would be manufactured and accessible, public water systems would benefit from the energy savings, Lin said.  In theory, the Smart Pipe would have a tiny generator turbine to power the instrument.

'Applying this technology at an affordable cost will help small and rural public water systems implement government water quality standards and manage water systems operations—and it won’t disturb the flow field,' Lin said.  Additional sensors could be added eventually to analyze water quality, he said.

This technologically advanced prototype was developed through a collaboration between a hydrologist and an electrical/computer engineer, illustrating how science can be advanced when researchers seek out projects with collaborators outside of their own field.

'Until recent years, hydroscience hasn’t used advanced technology as much as a few other fields, such as medicine and engineering,' Lin said.  'Multidisciplinary research can provide unique opportunities for gaining knowledge and for product development.'

This project was funded by the Midwest Technology Assistance Center (MTAC), which is a program of the Illinois State Water Survey(ISWS) and the Illinois Water Resources Center at the University of Illinois (U of I). The ISWS, a Division of the U of I Institute of Natural Resource Sustainability, is the primary agency in Illinois concerned with water and atmospheric resources. MTAC is one of eight research and assistance centers (TACNet) funded by the US EPA to provide technical, managerial, and financial assistance to small public water systems across the country.