EL PASO, Texas -- While thousands of borderland residents flock toward the cool waters of Wet N' Wild Waterworld on Saturday, pyrotechnicians are outside in the heat, preparing for the Fourth of July fireworks display.

"We've got 3-, 4-, 5-, 6-inch shells all going up, and we're roughly right at about 800 shells going up in the air tonight, and so it's going to be a big shoot. It's going to fill the sky," said pyrotechnician Wendell Powers.

And putting together the show is a day's work.

"Getting all the shells dropped into the mortars, then you have to get them wired, they get plugged into a certain channel because we do everything by electronic fire, so it's a six-to eight-hour process," Powers told KFOX.

Wet N' Wild Waterworld officials expected 5,000 to 6,000 people inside the park, with thousands more outside to experience the show.

"They'll be shooting off for about 25 minutes, several 6-inch shells that are going to be going off, so it's going to be seen and heard for miles around," said Chandra Edwards-Cottingajm, general manager of Wet N' Wild Waterworld.

So when it comes to the Fourth of July and fireworks, what is a pyrotechnician's favorite part?

"The finale is always the best, because what happens is all at one time we have, I think, 180. We have 180 shells going up at one time, and it's at the very end of the last song," said Powers.

While KFOX was out at Wet N' Wild Waterworld, its crew saw a number of law enforcement officers and firefighters prepared for the fireworks show and the crowds that come with it.