We a boat ride with police on Lake Houston to find out exactly what they're on the lookout for.
HPD officer Gary Crawford has patrolled Lake Houston for more than nine years now.
"There is no speed limit on the lake. However, if they're operating their vessel in a negligent manner, I will stop them," Crawford said.
His job is to keep boaters safe. And on a holiday like Independence Day -- with increased traffic -- just being seen on the water can do that.
"The main thing out here on a holiday is high visibility to prevent more or less the knuckleheads from acting up," Crawford said.
There is full time law enforcement on the 12,000-acre lake. Crawford says 80 percent of the boaters there have some sort of safety violation. So they'll stop vessels randomly and they don't need cause.
"I've got 1,2,3,4,5 people -- I need to see wearable 5 PFDs, that's life jackets," Crawford asked a group of boaters.
One boater got an A but also a warning for a damaged life preserver.
"The reason this one needs to be replaced and it's no longer any good is because of the rip right here," Crawford said.
"You get out here and you get hurt and don't have something to save you, you'd be in trouble. So it's very important that you maintain and keep up with all of your safety equipment," Lake Houston boater Roger Canady said.
As for drinking and boating, it's allowed, so long as the driver isn't drunk.
"On a vessel you can have open containers. It is legal to have an open container of alcohol," Crawford said.
In most cases -- aside from boating while intoxicated -- HPD's lake patrol will give boaters warnings without issuing tickets.