Three local teenagers were killed and one was severely injured in a hit-and-run collision on a narrow stretch of the Colorado River called the Parker Strip at the end of the 2003 summer boating season.

The Register first reported the story by talking to the kids' friends, boaters, locals and law enforcement officials who patrol the waters on the Arizona and California sides of the river and its tributaries...

Using the Coast Guard data, I ran queries summarizing data by year, looking at how boating accident trends in California, Arizona and Nevada were different from the national trends, comparing various lakes and rivers, looking at sizes of boats involved in accident.

While the number of boating accidents, fatalities and injuries nationally had declined steadily, I found a sharp two-year spike in the hit-and-run accidents and a growing number of alcohol-related accidents and fatalities.

The increase in hit-and-run accidents turned out to be a product of dirty data. After talking to boating law administrators in about a dozen states with the sharp increases, I learned there had been data entry errors when the U.S. Coast Guard switched to a Web-based reporting form.

So booze and boating became the focus of my reporting.

I spent the July 4, 2004, holiday weekend on Lake Havasu and Parker Strip. The lake and the strip, although connected by water, seemed like two separate worlds. The lake was open and calm, with a few large boats and partiers congregating in coves. The strip was more crowded, its waves choppier.

As I wrote my first draft, the story became more about the river and the people who gathered there for its party atmosphere. Soon, a phone call from a relative led me to the accident that became the center of the story.

The story turned into a tale of two Orange County men who went to the river for a July 4 weekend, where their paths crossed. Both had alcohol in their blood. One of them died in an accident. Another one was arrested and later convicted of negligent homicide. The numbers and trends I got from the data became the frame that held the story together.

I returned to the river with my Garmin eTrex Legend Global Positioning System unit and logged the locations of accidents, the sheriff station, and the hospital. I drove to key locations checking times and distances. I also started noting and logging drinking establishments along the river.

Later, in the office, using the records obtained in my reporting, I created a timeline of the accident. I assembled a spreadsheet tracking witnesses mentioned in police reports and what they said they saw...

You can read the story, "A Dangerous Mixture" online at www.ocregister.com/ocr/2004/10/03/sections/news/news/article_260375.php.