BANGOR, Maine — For the third straight year — and four of the last five — a Bangor High School student has been chosen Maine state winner for the annual U.S. Stockholm Junior Water Prize.

Leila Musavi, a 16-year-old graduating senior, will be one of 51 — Puerto Rico is included — high school students attending the national competition in Chicago June 23-25.

“I’ve always liked the sciences from an early age,” said Musavi. “Both my parents have careers in science, and it’s cool to research topics no one has studied before. I like the unknown part of it and discovering things.”

The 16-year-old avid dancer, runner and cyclist learned some things about herself along the way too.

“I hit a lot of roadblocks along the way, but that taught me to be patient and resilient,” she said.

Musavi’s science project, “development and optimization of gold-nanoparticle modified carbon electrode biosensor for detection of Listeria monogytogenes,” involves a rapid detection system for finding pathogens like cholera and E. coli in water using screen-printed carbon electrodes.

The Stockholm Junior Water Prize is considered the world’s most prestigious youth award for water-related science projects.

Musavi, who is attending Columbia University in the fall to study medicine, also won the New England Junior Science and Humanities Symposium in April and recently attended the national competition in San Diego, finishing among the top 27 entries and won a $2,000 scholarship.

Musavi’s mother, Monir, is a psychiatrist and her father, Mohamad, is an electrical and computer engineer at the University of Maine. Younger brother is Amir is a freshman at Bangor High.

What’s the secret to Bangor’s impressive run of winners of the prestigious award — an award Musavi’s teacher calls the Heisman Trophy Award for high school science students?

It depends on whom you ask.

“It’s not really a secret. It’s good kids,” said Cary James, chemistry teacher and head of Bangor’s science department. “And water is a passion of mine, so I try to get kids focused on that area and they’ve really done a great job .”

While admitting it takes a lot of work and self-motivation, Musavi also gives James a lot of credit.

“I think the reason we’ve won so many times is because we have a really amazing teacher,” she said. “He’s great at motivating us and is very supportive.”

Jennifer Row started the run with the state award in 2007, Anne Marie Lausier won in 2009 and Rebecca Ye won both the state and national award in 2010 for creating a biosensor capable of rapidly identifying strains of the pathogenic bacteria E. coli.

“Leila’s project is essentially an offshoot of Becky’s last year, but she uses a different platform,” said James. “Leila’s using a tool analogous to a glucometer, which diabetics use for check their blood sugar. This thing can be used the same way.”

Musavi credits Ye for inspiring her.

“When I saw her presentation, that’s what got me really interested in biosensors and micro technology,” explained Musavi, who has worked in the same University of Maine lab as Ye in an independent studies credit capacity since last June.

Both James and Musavi have a passion for this kind of research.

“Yes, especially since it’s so pertinent today with so many countries having so many problems with sanitation systems and unsafe water,” Musavi said.

“It’s arguably the greatest natural resource we have and in the future, wars will be fought over water, not oil or other natural resources,” said James, who has had his students participate in the Stockholm contest for 12 years since he arrived at Bangor.

If she wins the national award, Musavi will receive a $3,000 scholarship and all-expenses paid trip to Stockholm, Sweden to compete for the international award. She also has the opportunity to present her research to thousands of water quality professionals at WEFTEC 2011, the Water Environment Federation’s 84th annual technical exhibition and conference in Los Angeles.