We all like to think that the water we're drinking is safe. But how do we know? In 2000, residents in Walkerton, Canada, learned not to trust their drinking water supply. E. coli contaminants entered the water system. It caused six people to die and many more to become seriously ill.
Although no one knows exactly how the water became contaminated, some suspect that the chlorinator at the water treatment plant wasn't working, and that perhaps nearby farms were contaminating the groundwater supplies.
Joan Wu is a biosystems engineer at Washington State University. She didn't work on this particular issue, but she is concerned about water supplies in general. "Whether it's for agricultural purposes or for domestic use, I look at water movement," she says.
"It's important that we look at the physical processes of water movement," she says. This water is generally found in three areas: beneath the ground in the aquifer, along the surface in rivers and streams and in the all-important root zone.
"Crops have roots that stretch beneath the ground about one to two meters [three to six feet]," Wu says. "I'm interested in every area of water, but this zone is especially important for agriculture."
Is the groundwater supply clean? Is the aquifer being drained too quickly? Is agriculture contaminating the water supply? Water is such a valuable resource that there are many questions that need to be asked and answered.
Of course, studying moving water is often difficult. "It's very challenging work," she says. While studying groundwater, scientists often have to work with limited data.
"Because the water is beneath the ground, we have to get access to it," she says. "Building monitoring wells is expensive, so we don't have as many as we'd like. The lack of data is always frustrating."
Nonetheless, Wu perseveres and conducts her experiments on moving water, and teaches courses in hydrology. "I really enjoy my work," she says. "I'd encourage any young person to enter this field. It's so important and it's enjoyable."
Just as important as water is food. When we go to the grocery store, we assume that the products we buy will be fresh. But if they've been shipped across the country, how do the perishable and non-perishable items stay fresh and safe to eat?
There is a whole science behind this industry. Biosystems engineers also work in food science, and in the complex area of food packaging. "Most people just think of the package as a non-edible protective layer," says Jung Han, a professor. He says it's much more complicated.
A package has to protect food against chemical, physical and microbial damage. "Chemically, the package has to provide a good barrier against oxygen to stop the growth of bacteria or mold," he says. He also explains that the package should protect against water damage and water vapors. "It's important to retain flavors."
It's easy to imagine why food has to have protective packaging. Some foods are shipped across the country on trains and trucks and are transported from distribution houses to grocery stores.
Imagine potato chips without their protective packaging. They'd be piles of yellow dust long before they hit a store's shelves. Other food simply couldn't be shipped. "Just think: you couldn't ship water without bottles," says Han.
Microbes can cause food to rot, and can cause serious illness in people. "Food is sensitive to microbes and so the packaging has to be clean and closed against the environment," says Han.
Of course, Han also has to consider the information that needs to go on every package such as brand names, nutritional labels and recipes. All foods need to be packaged and labeled according to industry standards.
But packaging requirements also trouble engineers. "Thirty percent of the solid waste going to landfills is packaging," says Han. This is something he'd like to change. In his efforts to create new packaging, he always looks for biodegradable alternatives.
Packaging is much more complex than dumping a handful of candies into a cardboard box. "It's much more difficult than other types of packaging because you have to specialize in food science, [and] know the physical properties of the food." For Han, these added requirements only make his job more interesting.
John Perumpral is a professor at Virginia Tech and the department head of biological systems engineering. He says to get into the field, a bachelor's degree in biological systems engineering is generally a requirement. "This degree is offered by Virginia Tech," says Perumpral.
He estimates there are approximately 200 people working in this field in Virginia and adds that the job outlook is likely on the rise. "[It's] excellent. [There's a] robust economy, broad engineering program [and] specialized training."
Perumpral says an average salary in the field could be quite varied. "[It] ranges from $40,000 to $50,000, depending on area of specialization and location."