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Clean drinking water and sanitary toilets can save millions of lives in developing countries, and Portland State University is doing something about it.

The Sustainable Water, Energy and Environmental Technologies Laboratory, or SWEETLab, at PSU develops and delivers life-saving technologies to countries in Africa. Just last week, PSU development technician and research assistant Zachary White left for Rwanda and Kenya with lab-developed technology that will allow usage of hand-powered water pumps and manufactured latrines to be monitored.

In the past 10 years, thousands of water pumps have been installed in Africa by various agencies, bringing reliable clean water to rural areas, mechanical engineer Zdenek Zumr said. He manages the PSU lab under the direction of its founder, Evan Thomas.

Thomas, a PSU engineering faculty member, in October spoke during a PDXTalks event about the efforts of different agencies 鈥� ranging from church groups to the World Bank 鈥� to provide clean water and sanitation in underdeveloped countries.

鈥淗ow do we actually know they’re working after we leave?鈥� he asked.

About half of the water and sanitation infrastructure installed every year in those countries is broken 18 months after being installed, Thomas said, 鈥渁nd in many cases never gets fixed.鈥�

That problem is one being tackled by the SWEETLab staff. It’s developing products to measure the effectiveness of technologies being employed in underdeveloped countries through SweetSense Inc., a commercial spin-off that markets products in Africa.

When White left last week, he took with him 200 sensors to be installed on water pumps in Rwanda and output-measuring scales to be installed on about a dozen manufactured latrines in Kenya.

These technologies are important because follow-up is needed, Zumr said. Although many manufactured hand-powered water pumps have been installed, there’s no reliable way to know when they should be serviced.

鈥淎bout 40,000 pumps are installed all over Africa bringing reliable clean water to rural areas,鈥� Zumr said. 鈥淭hen people show up with rubber tanks and take it home.鈥�

But with half the pumps broken half the time, people often must travel from one pump to the next to find one that works, he said. Millions of dollars were donated to install these pumps, but few provisions were included for follow-up maintenance.

The sensor that PSU developed is a small green box, only about four inches by six inches, that attaches to the side of the water pump. The sensor uses cellphone signals to transmit the pump’s performance to the cloud, where it can be accessed online. Also, text messages and email alerts are sent out when there’s a problem.

White said the box, nicknamed 鈥淏art,鈥� measures pump vibrations.

鈥淚t can count the number of strokes it takes for the water to come to the surface and tells us how the seals are working inside the pumps,鈥� Zumr said. 鈥淚t also captures water flows and can keep track of the pumps, and then (service technicians) can cluster service calls.鈥�

If a pump continues to fail, he said, a service technician can use a smartphone to order parts online,鈥� he said.

One might wonder about the availability of smartphones in predominantly rural Rwanda, but Zumr said virtually everyone has a phone or access to one.

鈥淭hey may not have shoes or running water, but they do have a cellphone,鈥� he said. 鈥淧eople don’t have electricity and there’s a little micro economy around charging phones. They may not have a phone, but they’ll have a SIM card and borrow someone’s phone.鈥�

Zumr said the Bart sensor, which runs on batteries, is meant for long-term use thanks to energy-saving capabilities.

鈥淭he sensor has a microprocessor that can be put to sleep where it consumes almost no energy,鈥� he said. 鈥淭hrough clever external circuitry, it has the ability to wake it up when an event is detected.鈥�

When the processor wakes up, it analyzes the signal coming in and determines whether it’s a recordable event that passes a certain measurement threshold or just noise, Zumr said.

鈥淚t waits to see if the motion detected is consistent with the pump handle being used, and the reason for that is it could be an animal rubbing against it or a truck passing by,鈥� he said.

The sensor records the event through a pressure 鈥渢ransfuser,鈥� Zumr said.

鈥淭hrough the pumping motion the water comes to the surface and floods the head of the pump before it flows through the spout,鈥� he said. 鈥淲ith each stroke it fills up the head to one or two inches and then we can detect the water volume in the pump head.鈥�

The Bart sensors were developed at the SWEETLab; however, the latrine measurement instrument, which is about the size of a bathroom scale, was developed by Sanergy, a nonprofit that also maintains them.

鈥淓ssentially what they’ve done is take the inner workings of how a digital bathroom scale would work and built an extremely rugged version that will upload data,鈥� Zumr said. 鈥淭here are two containers 鈥� one for feces and one for urine 鈥� and the scale measures them individually.鈥�

From that data, PSU can provide information through the cloud to Sanergy, which can determine a maintenance schedule for the latrines.

鈥淥nce we have the data and it’s processed into readable information, then based off the date, we can make little sub-programs that can alert people in charge of emptying the station,鈥� Zumr said.

The end result of taking the sensors and the scales to Africa is 鈥渆ngineering with a humanitarian aspect,鈥� White said, but it also has industrial applications.

鈥淚t’s also an application to provide monitoring systems to clients who don’t want to spend money on an industrial-grade system to monitor building performance, for example,鈥� he said.

The Bart sensors can monitor temperature, moisture, radiation, air current and wind speed among other data, White said.

鈥淎nything you can turn into an electrical signal we can monitor,鈥� Zumr said.

To learn more about the SWEETLab and SweetSense, visit and .