Campers, paddlers and hikers might want to have a Plan B for the July 4th holiday with rising rivers causing closures and cautions across the region.

Heavy rains in the past week have swollen lakes and increased river flows from the Dakotas across Minnesota and into Wisconsin. Steve Buan, hydrologist with the North Central River Forecast Center and based in Chanhassen, noted that more than a foot of rain fell in the past five days over the area between La Crosse, Wis., and Dubuque, Iowa, with numerous single 5- to 6-inch rainfalls from the Red River Valley across central Minnesota.

At Fort Snelling State Park, trail flooding led officials to close the popular Pike Island on Tuesday and to begin shutting off water and removing portable toilets from Picnic Island. With the Minnesota River expected to rise 4 more feet by the weekend, it’s likely that the entrance road to the park will also be closed to vehicles, assistant manager Dave Felleson said. People will still be able to get into the park by walking or biking from the area around Historic Fort Snelling or from Minnehaha Park.

Felleson added that people with reservations for the Picnic Island shelters in the coming days will be asked to change dates or will be given a refund.

On the Mississippi River, the metro area’s three locks and dams, closed to recreational boat traffic due to heavy flows Monday, could reopen after the weekend. The St. Croix River at Stillwater has been a no-wake zone this season because of bridge construction — and will be for the next three summers — but the Minnesota DNR expects Wednesday to declare the river a no-wake zone from Hastings all the way to St. Croix Falls, Wis., boating law administrator Stan Linnell said.

The low-lying Lilydale area upstream from downtown St. Paul could also see some Mississippi River inundation, and some streets and bridges in the Jordan, Chaska and Shakopee areas of the southwest metro area might be threatened by the rising Minnesota, but no major commuter routes are expected to be affected.

The Red River and its tributaries in northwest Minnesota are also rising dramatically. A floating pedestrian bridge between Fargo and Moorhead was removed in recent days, but Fargo city engineer April Walker said there should be no major effect on roads or homes.

Erik Wrede, water trails coordinator for the DNR, said that rivers will be challenging for paddlers and boaters during the high water period and probably not suitable for beginners. He recommended that paddlers choose larger rivers that offer longer sightlines and are less likely to be blocked by trees. Boaters should also scout the parts of rivers they’ll be traveling.

And of course, Wrede and Linnell added, boaters should wear life jackets.