Josslyn Dodds was born and raised in Williston, N.D., and remembers what life used to be like before the boom hit. She left her doors unlocked, let her kids bike around the neighborhood and never worried about what they were up to because she knew all their friends and their friends' families.

Now that the population has tripled, crime has spiked and car accidents are growing more common, she hates to let her two girls -- ages 6 and 11 -- out of her sight.

"It's a lot different now," she said. "In the first years of [my daughters'] lives, they would have their cousins over and all walk to the park on their own -- now I don't let them leave the house without their cell phones."

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The upside: Dodds works at her father's pharmacy, and business has been great. The boom has also brought her a whole new group of friends from all different parts of the country.

"There are so many awesome people coming here -- there are always going to be a couple bad apples, but for the most part there are a lot of good things happening," said Dodds.