McHenry County officials are urging people along the Fox River to get their sandbags and “go” bags ready ahead of more rain in the forecast.

The weather service has issued a flood warning until further notice for the Fox River, stretching from Johnsburg to Red Gate Road in St. Charles, including at the Algonquin Lock & Dam, affecting McHenry, Lake and Kane counties.

County officials said creating sandbag barriers along waterfronts can help protect property from flood damage.

“Sandbags only work to protect property if they are deployed wrapped in plastic before the water rises,” David Christensen, director of McHenry County Emergency Management, said in a county news release. “Now is the time to create your barriers before additional storms come into the area on Saturday.”

Flooding can also contaminate wells and disrupt septic systems.

“A water well which has been submerged must be considered contaminated and unsafe to drink for cooking, drinking, preparing food, baby formula or brushing teeth. Obtain bottled water or bring tap water to a rolling boil for at least 5 minutes before use,” according to the release.

Private sewage disposal systems under water also won’t function correctly and shouldn’t be used, and the best choice is to find alternative housing until flood waters recede.

“If alternative housing is not available, it may be possible to utilize a portable or chemical toilet temporarily,” according to the release.

In Nunda Township, officials have been working to sandbag and protect properties along the river. Highway Commissioner Rob Parrish said the efforts began Wednesday night, with volunteers and crews working to fill 2,500 to 3,000 bags per hour.

“Nunda [Township] has three sandbaggers running and four trucks delivering sandbags,” Parrish said, adding crews from Bull Valley, Prairie Grove, Island Lake, Lakemoor, Dorr Township and inmates from McHenry County Jail are helping.

As of mid-day Thursday, the township had made and delivered 10,000 sandbags, Parrish said.

The EMA is sharing bags with townships and residents who want sandbags can reach out to their townships or municipalities to get them, according to the release.

Algonquin Public Works staff have started preparing to sandbag, Director Nadim Badran said. The village also closed Cornish Park in the downtown area out of precaution.

County officials said residents should not drive or walk through floodwater. People should use caution on low-level roadways and areas beneath viaducts or adjacent to waterways.

“A mere six inches of fast-moving flood water can knock over an adult, and standing water can spread illnesses to people and pets,” according to the release.

The McHenry County EMA said when “there is a chance of flooding or adverse weather conditions,” it is a best practice to have a go bag with food, water, extra clothes, charging cords, important documents and a first aid kit. Pet emergency kits should include leashes, harnesses or carriers to transport pets safely, according to the release.

The Fox River is not expected to crest until next week.