The ban on alcohol in San Marcos city parks is one of many new rules taking effect Jan. 1.

Fire Marshal Ken Bell has spent the past several months fielding an outreach and education campaign to let San Marcos residents know about the changes. The ban will be enforced with a light touch, he said.

"We're not walking around doing cooler checks," said Bell, who heads up the city's park ranger program and advocated for the revisions. "If you wanted to enjoy a beverage with your family at a table, I would never know unless you're screaming at someone and you can't control yourself."

In a major exception to the ban, people will still be able to drink alcohol when they are in the river, whether tubing, swimming or wading, because waterways in Texas are owned by the state, whose rules preempt the city's.

"If you want to stand there in the river and drink a 12-pack of beer, knock yourself out. But you better not walk your beer through the park where we can see it," Bell said. "If you are straddling the waterway, you can't put your pinkie toe in the water and claim [you're exempt]. That's not going to work. You'll find yourself in a tizzy of trouble at that moment."

To access the river, revelers will be required to carry their alcohol through designated entry points at the parks, the ordinance states.

Tubers and kayakers who drink have not traditionally posed problems in parks, according to Bell, who said more problems arise from people who spend an entire day drinking. In the 10 years leading up to the ordinance's passage, he said his department had made only one arrest at city parks that wasn't alcohol-related.

In addition to the alcohol ban, the ordinance prohibits Styrofoam, including ice chests and cups. The new rules create tobacco-free zones in play areas and athletic fields, allow barbecue pits and pop-up tents in designated areas, and require permits for the use of spears and spear guns for fishing in the San Marcos River.

Ice chests and coolers must come equipped with properly secured lids as well. The city is also increasing the minimum fine for littering from $150 to $250 in the river and parks.

City Council approved the ban in May. After the rules have been in effect for one year, they are scheduled to be reviewed by the council in January 2014.