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Canal is deadliest crossing for illegal immigrants

By Janet Shamlian, NBC News Correspondent

 IMPERIAL VALLEY, Calif. – It stretches for 82 miles, carrying water from the Colorado River to San Diego and the agriculture-rich Imperial Valley. And while many consider the irrigation canal called the "All-American Canal" a lifeline for the region, at least one Southern California man says it is nothing short of a deathtrap. 

I recently spent the day with Dr. John Hunter at a portion of the canal about 30 miles west of the city of El Centro. It's a pretty desolate area – dusty and hot, it's the desert. Hunter is a physicist who has found himself someplace he'd rather not be – squarely in the middle of the national immigration debate.

VIDEO: Canal is deadliest crossing for illegal immigrants

For several years, Hunter has been lobbying for climb-out ladders and buoy lines along the canal. Because the waterway is close to the border, illegal immigrants sometimes try to make their way to the U.S. by swimming across.

It's a real gamble. Even in the triple-digit temperatures they often see here, the water is cold and the current, swift.

Over the years, more than 500 people are believed to have drowned in the canal. Not all were trying to reach American soil.  A little girl named Alejandro drowned trying to save her older sister, and a border agent went in trying to rescue his dog. 

We know the names of these victims, but hundreds of others are unidentified. Perhaps their families believe they're alive and working in the United States when, in fact, they may be buried in unmarked graves in a small cemetery filled with many who tried to cross the canal and failed.  

Hunter and his wife, Laura, took me to that cemetery. Hundreds of crosses stuck in the burning dirt, each marking a life lost. Some are children. Regardless of how you feel about people trying to cross into this country illegally, you can't help but be struck by this tragic patch of earth.

To hear the Hunters tell it, those who manage the All-American Canal have been dragging their feet on more safety measures. Many oppose their plans for more safety measures and question whether taxpayer dollars should be spent on them. 

The Imperial Irrigation District, the agency overseeing the waterway, has posted warning signs about the dangers. And a very graphic public service announcement airing in Mexico aims to do the same.

Critics say more buoys and ladders would serve only to encourage more people to take the gamble of their life.