Electrical engineering senior design students at The University of Alabama in Huntsville (UAH) recently designed an automated chlorine dispenser to upgrade the water supply for a village in Sabana Larga, Nicaragua. The project was performed in conjunction with the UAH chapter of Engineers Without Borders (EWB). EWB USA is a non-governmental organization which works on engineering-oriented international development work.
Four electrical engineering students, Nicole Barnes, Noah Girkin, Audrey Simms and Mary Stewart, enrolled in the College of Engineering at UAH, a part of the University of Alabama System, worked together as ‘Team Gyrados’ to design and implement the dispenser system as part of their EE494 Senior Design course. The team is advised by Dennis Hite, a senior lecturer in electrical and computer engineering.
“UAH EWB has been working in partnership with Vanderbilt University’s EWB chapter to create a new water supply system for the village,” says Zach Helton, a recent UAH graduate in aerospace engineering and atmospheric science who is the current president of UAH’s student chapter of EWB. “To say that I’m impressed with Team Gyarados’ work would simply be an understatement. We have remained in contact with the members of the team to make any modifications to the system in preparation for our eventual implementation trip to Nicaragua.”
Sabana Larga, population 209, is extremely remote, located in the mountains of northwest Nicaragua near the La Trinidad municipality. The community has faced a critical issue of access to potable water following a severe tropical storm that left the inhabitants with a broken water distribution system and an insufficient supply of water, which for many meant traveling up to one mile each way to obtain a daily supply.
The community asked EWB to design and implement a new water system, a four-part project that incorporated source development, water distribution, water storage and water treatment. During the assessment trip to select a new freshwater source, testing revealed the presence of E. coli in the new source. To ensure safety, the UAH team developed an automated chlorine dispenser to treat the community’s drinking water for the bacteria, while continually monitoring water quality.
"I was excited that we found a project that would result in helping people improve their everyday lives,” says electrical engineering student and team member, Audrey Simms. “It was a big motivation throughout the project to know where this project would end up and that it can help more than 200 people receive clean drinking water. I was also glad that we were able to partner with a university club, Engineers Without Borders, at UAH to help with a project and that our classes gave us the skills needed to complete it."
The team incorporated electronics to control the bypass valve and provide feedback water quality measurements to a microcontroller programmed to automate the chlorine dosing. The system determines how much chlorine dosing is required by monitoring the water quality to report back pH and oxidation reduction potential measurements (ORP). ORP is an important measurement to quickly determine overall water sanitation. If the system determines more or less chlorine dosing is required, it regulates the total water flow over 3” chlorine tablets. The implementation of the water project will be performed in two phases to supply the community with potable drinking water. The water pump and storage tanks will be set up this fall, with the chlorinator and distribution lines to follow in spring 2024.
The project proved to be interdisciplinary in nature, as coursework supporting the completed design included senior design and electrical circuit and systems design and modeling; controls and robotics; three computer programming engineering classes and assembly language support for programming a microcontroller. The team also used skills learned from the UAH College of Arts Humanities and Social Sciences to produce written technical documentation for the community as a User Manual in formal Spanish.
